ISO 10934:2020 顕微鏡—光学顕微鏡用の用語, 語彙 | ページ 5

3.2.1

音響光学変調器

結晶内の音響誘起 回折格子（3.1.42 ）によってレーザー（3.1.86） の方向および／または 強度（3.1.79） を制御するために使用される電子的に調整可能なデバイス。

3.2.2

音響光学チューナブルフィルター

AOTF

結晶内の音響誘起 回折格子（3.1.42） によって波長を選択するための電子同調 フィルタ（3.1.55） 。

3.2.3

エイリアシング

低すぎる周波数 (つまり、ナイキスト周波数よりも低い周波数) でのサンプリングによって引き起こされる現象で、情報の損失および/または誤った情報の作成を引き起こします。

3.2.4

オートフォーカス

対象物（3.1.104） を自動的に 焦点（3.1.65） に合わせる方法。対象物の位置を検出するイメージング ソフトウェア アルゴリズムおよび/またはハードウェア デバイスによって制御されます。

3.2.5

バックグラウンド減算

オブジェクト（3.1.104） が存在しない場合に存在する信号のその部分を除去して、下にある 画像（3.1.75） 情報を明らかにする

3.2.6

ビニング

隣接する ピクセル（3.1.116） の電荷が蓄積され、単一の値として読み出されるイメージ センサーの動作モード。

3.2.7

共焦点

理想的には、 物体視野（3.1.54.5） 内の点が 光 の回折限界スポット（3.1.88）によって照らされ、この点から発せられる光が集束され、より小さな領域から検出される顕微鏡状態。後続の フィールド面（3.1.117.2） の対応する位置にある 回折ディスク（3.1.7.1） の中央領域

3.2.8

チャネル

1 種類の 画像 (3.1.75) 情報を含む特定の信号経路

3.2.9

共同ローカリゼーション

同じ オブジェクト（3.1.104 ）に対応する ピクセル（3.1.116） の一致による デジタル画像（3.2.13） のオーバーレイ 異なる情報を含むポイント

3.2.10

共焦点顕微鏡

理想的には、 物体面 (3.1.117.5) 内 の点が回折限界の 光 スポット (3.1.88) によって照らされ、この点から発せられる光が集束され、より小さな領域から検出される顕微鏡技術。後続の フィールド面（3.1.117.2） の対応する位置にある 回折ディスク（3.1.7.1） の中央領域

注記1対象物を走査するか，照射スポットと検出スポットを同時に走査することにより，拡張領域の画像が形成される。

注記2:共焦点の原理により、焦点外の面からの光が抑制されるため、軸方向の分解能が向上します。

3.2.10.1

レーザー走査型共焦点顕微鏡

光源（3.1.88） が レーザー（3.1.86 ）である共焦点顕微鏡（3.2.10 ）。

3.2.10.2

マルチビーム共焦点顕微鏡

複数の照射スポットと検出スポットを同時に使用する 共焦点顕微鏡法（3.2.10）。

3.2.10.3

ニポウ円板共焦点顕微鏡

ニポウディスク（3.2.10.3.1） を用いて照射及び検出スポットの 走査（3.2.41） を 行う共焦点顕微鏡（3.2.10 ）。

3.2.10.3.1

ニポウディスク

アルキメデスのらせん状に配置された、理想的には同一の、多くの小さな穴がある不透明なディスク

3.2.10.3.2

タンデム走査型共焦点顕微鏡

照明 光（3.1.88） と検出光が別々の穴を通過する ニポウ円板共焦点顕微鏡（3.2.10.3） 。

3.2.10.4

分光共焦点顕微鏡

物体（3.1.104） の空間位置に対応するスペクトルが記録される 共焦点顕微鏡（3.2.10 ）。

3.2.10.5

シータ共焦点顕微鏡

2つの 対物レンズ（3.1.106） が互いに角度θで配置され， 焦点（3.1.63） が 物体（3.1.104） 内で一致する 共焦点顕微鏡（3.2.10） が使用される。それぞれ 興奮（3.1.49） とコレクション

3.2.10.6

白色光共焦点顕微鏡

照明（3.1.73） 光源（3.1.135） 及び可視スペクトル全体で動作する検出器を使用する 共焦点顕微鏡（3.2.10） 。

3.2.10.7

共焦点広がり関数

共焦点顕微鏡（3.2.10） における照明及び検出光学系の 点広がり関数（3.2.34） の積。

3.2.10.8

共焦点ボリューム

共焦点顕微鏡（3.2.10 ）で像（3.1.75） を生じさせる 物体（3.1.104） の各点の周りの有効体積。

3.2.10.9

4pi 共焦点顕微鏡

物体（3.1.104） 内 で 焦点（3.1.63） が一致する2つの対向する 対物（3.1.106） レンズを使用して， 像（3.1 .75) 信号が導出され、さらに処理する ことで、デジタル (3.2.13) or 電子画像 (3.2.15) が生成され、 軸方向の解像度が向上します (3.1.128.5)

3.2.11

デコンボリューション

<microscopy>逆フィルタリング技術によって空間ドメインまたは周波数ドメインで実行される、ぼやけを減らすための数学的手法

注記 1:デコンボリューションが測定値ではなく理論のみに基づいている場合、それはブラインド デコンボリューションとして知られています。

3.2.12

デジタル的に強化されたコントラスト

コントラスト（3.1.32） デジタル画像（3.2.13） の強度及び／又は色値の操作によって強化されたもの。

3.2.13

デジタル画像

イメージ (3.1.75) で、情報がバイナリまたは別のマシン コードの形式である

3.2.14

電子画像

情報が電気信号の形である 画像（3.1.75）

3.2.15

拡大被写界深度顕微鏡

点像分布関数（3.2.34） が拡張された焦点範囲にわたって実質的に不変になるように既知の方法で変更され、さらに処理することによって デジタル（3.2.13） or 電子画像（3.2.14 ）が得られる顕微鏡法 ) 拡張された 被写界深度 (3.1.36)

3.2.16

拡張フォーカス画像

<画像処理> 画像スタック（3.2.27.1） を介した投影で ピクセル（3.1.116） の強度値を合計することによって得られる二次元 デジタル画像（3.2.13 ）。

3.2.17

蛍光相関顕微鏡

共焦点体積（3.2.10.8） 内で発生する時間依存 強度（3.1.79） 変動を用いて蛍光分子の移動度を計算する顕微鏡検査。

3.2.18

蛍光in situハイブリダイゼーション顕微鏡法

魚

in situハイブリダイゼーションによって染色体または染色体内の特定の位置を蛍光標識できる顕微鏡法

3.2.19

蛍光寿命イメージング顕微鏡

フリム

特徴的な 蛍光（3.1.58） 減衰率の識別に基づく画像化技術

3.2.20

光退色後の蛍光回復

フラップ

物体（3.1.104） の領域を照射してその 蛍光（3.1.58） を枯渇させ、その後の照射領域の蛍光の回復を測定する技術

3.2.21

蛍光共鳴エネルギー移動

フェルスター共鳴エネルギー移動

フレット

近接した 2 つの蛍光体間のエネルギーの非放射移動

3.2.22

フレーム平均化

同一条件下で記録された連続 デジタル（3.2.13） or 電子画像（3.2.14） からの ピクセル（3.1.116） 値の平均

注記1：信号対雑音比を高めるために使用される。

3.2.23

イメージインテンシファイア

検出器の範囲と一致するように信号のダイナミック レンジを拡大するデバイス

3.2.24

リニアアレイセンサー

感知素子の列の形をした検出器

3.2.25

最大強度画像

<画像処理> 画像スタック（3.2.27.1） による投影における最大 ピクセル（3.1.116） 強度値から導出された二次元 デジタル（3.2.13） or 電子画像（ 3.2.14）。

3.2.26

マイクロチャンネルプレート

検出器アレイの前に配置されたデバイスで、入射光子束を二次放出で乗算します

3.2.27

多次元画像データセット

デジタル（3.2.13） or 電子画像（3.2.14） のデータで、例えば三空間次元、波長、時間、偏光などのいくつかのパラメータを使用してサンプルからデータを記録することによって生成される

3.2.27.1

画像スタック

物体（3.1.104） の三次元領域から取得した 多次元画像データセット（ 3.2.27）。

3.2.27.2

フォーカスシリーズ

Zスタック

異なる焦点位置で取得した 画像スタック (3.2.27.1)

3.2.28

マルチモードファイバー

複数の横電磁モードを維持できる光ファイバー

3.2.29

多光子蛍光

蛍光（3.1.58） 複数のコヒーレント光子の同時吸収による 励起（3.1.49） 。

3.2.29.1

多光子蛍光顕微鏡

画像（3.1.75） が 多光子蛍光（3.2.29） によって形成される顕微鏡法

注記1:十分な励起強度は限られた焦点体積でのみ達成されるため、多光子蛍光は共焦点ピンホールを必要とせずに光学セクショニングをもたらします。また、より長い波長による励起も可能です。

3.2.29.1.1

二光子蛍光

コヒーレントな光子のペアによって励起された蛍光

3.2.30

光学部

厚い 物体（3.1.104） 内の厚さが光学系の 軸方向分解能（3.1.128.5） によって定義される薄い領域からの 画像（3.1.75） 。

3.2.31

写真の漂白

光（3.1.88） による分子の蛍光特性の破壊で，試料の 蛍光（3.1.58） が減少する。

3.2.32

ピンホール

<共焦点顕微鏡> 対象物(3.1.104 )と共役な平面 (3.1.29)に位置する 絞り(3.1.38) 。 対象物平面(3.1.117.5)内 の照射されるおよび/またはそこからの領域を制限する 光（3.1.88） が集められる

3.2.33

ポイント検出

画像（3.1.75） の制限された点のような領域から集められた 光（3.1.88） の検出。

3.2.34

点広がり関数

PSF

<顕微鏡システム> 点光源（3.1.135.1） の 像（3.1.75） における 光（3.1.88） の振幅または 強度（3.1.79） の分布の数式。

3.2.34.1

強度点広がり関数

点光源（3.1.135.1） の 像（3.1.75） における 光（3.1.88） 強度（3.1.79） の分布の数式。

3.2.34.2

振幅点広がり関数

点光源（3.1.135.1） の 像（3.1.75） における 光（3.1.88） 振幅の分布の数式。

3.2.35

ラマン顕微鏡

画像 (3.1.75) 情報源としてラマン散乱を利用した顕微鏡法

3.2.35.1

コヒーレントアンチストークスラマン散乱顕微鏡

CARS顕微鏡

分子振動を誘発するために複数の光子を使用し、コヒーレント信号を生成して 画像を形成する顕微鏡法 (3.1.75)

注記 1:属性の 1 つは、信号が自発ラマン放出よりも桁違いに強いことです。

3.2.35.2

誘導ラマン散乱顕微鏡

SRS顕微鏡

振動遷移の誘導ラマン励起によって生じる 励起（3.1.49） ビームの 強度（3.1.79） 変調を検出する顕微鏡技術。

注記1: SRS顕微鏡法の重要な特徴は、非共鳴バックグラウンド信号なしでより高いコントラストのイメージングを提供することです。

3.2.36

レシオイメージング

2つの 画像（3.1.75） の対応するピクセル値を割ることによって ピクセル（3.1.116） 値が得られる デジタル画像（3.2.13） を形成する

3.2.37

リアルタイムイメージング

収集された速度と同じ速度で画像を表示または分析する

注記 1:この速度は通常、試料内で観察され、連続的であると目で認識されるプロセスのダイナミクスにも比例します。

3.2.38

関心領域

ROI

個別の観察が適用される 画像（3.1.75） の部分。

3.2.39

スキャンレート

単位時間あたりに完了したスキャン サイクルの数

3.2.40

スキャンされたフィールド

オブジェクト空間（3.1.105） におけるスキャンされた領域の寸法

3.2.41

走査

物体（3.1.104） 内の領域の順次 照射（3.1.73） 又は検出。

注記1:スキャンは、対象物、照明ビーム、対物レンズ、または検出器を移動させることによって行うことができます。

3.2.41.1

デスキャン中

撮像ビームが 走査（3.2.41） 機構を介して照明ビームの経路をたどり，静止ビームを生成するプロセス。

3.2.41.2

ラインスキャン

単一の線に沿って スキャン (3.2.41)

3.2.41.3

スキャンされていない検出

NDD

デスキャン （3.2.41.1）を行わずに 走査型顕微鏡（3.2.42） で 画像（3.1.75） 信号を取得する技術。

注記 1:多光子蛍光顕微鏡で広く使用されています。

3.2.41.4

ポイントスキャン

光 のスポット（3.1.88）を使用して領域を スキャン（3.2.41） する

3.2.41.5

ラスタースキャン

線のパターンによる領域の 走査（3.2.41）

3.2.41.6

スリットスキャン

光 の棒（3.1.88）でエリアを スキャン（ 3.2.41）

3.2.41.7

ステージスキャン

ステージ（3.1.136） を動かし、それによって 物体（3.1.104） を動かすことによって実行される スキャン（ 3.2.41）

3.2.42

走査型顕微鏡

画像（3.1.75） が 走査（3.2.41） によって形成される 顕微鏡（ 3.1.99）

3.2.42.1

ディスク走査型顕微鏡

照明（3.1.73） および／または観察経路内で回転する穴あきディスクによって走査が行われる 走査型顕微鏡（3.2.42） 。

3.2.42.2

レーザー走査型顕微鏡

対象物（3.1.104） が レーザー（3.1.86） ビームによって走査される 走査型顕微鏡（3.2.42）

3.2.42.3

走査型近視野顕微鏡

走査型顕微鏡（3.2.42） 。小型の発光プローブが 対象物（3.1.104） を至近距離で走査する（またはその逆）。

注記 1:プローブの直径が Airy ディスクよりも小さい場合、超解像が達成される場合があります。

3.2.43

第二高調波発生顕微鏡

SHG顕微鏡

励起（3.1.49） 光（3.1.88 ）の第 2 高調波を使用して追加の 画像（3.1.75） 情報を提供する顕微鏡法

3.2.44

シェーディング補正

照明システム又は検出システムの不均一性によって生じる， デジタル画像（3.2.13） or 電子画像（3.2.14） の強度レベルを調整する方法。

3.2.45

シングルモードファイバー

単一の横電磁モードのみを維持できる光ファイバー

3.2.46

スペクトルイメージング顕微鏡

オブジェクトの空間位置に対応するスペクトルが記録される顕微鏡法（3.1.104）

3.2.47

構造化照明顕微鏡

SIM

対象物（3.1.104） を空間的に変化するパターンで照明して合成 画像（3.1.75） を生成し、そこから デジタル画像（3.2.13） を横方向および 軸方向の解像度（3.1.128.5） を向上させる顕微鏡技術。生産されるかもしれません

3.2.47.1

格子像顕微鏡法

対象物（3.1.104） が格子のパターンによって照明される 構造化照明顕微鏡法（3.2.47）

3.2.48

超解像顕微鏡

回折限界（3.1.128.1） によって与えられるよりも高い分解能を達成する顕微鏡技術。

3.2.48.1

ローカリゼーション顕微鏡

個々のマーカーの位置をローカライズし、それらの決定された空間分布のグラフィック表現を生成することにより、マークされた標本の 超解像顕微鏡 (3.2.48) デジタル (3.2.13) or 電子画像 (3.2.14) を作成する手法

注記 1:この画像の横方向の解像度は、各マーカーの位置特定プロセスの精度によってのみ制限されます。

注記2:マーカーは通常、光活性化または光スイッチ可能な蛍光プローブです。グラフィック表現を生成するために、通常、複数の画像が連続してキャプチャされます。

3.2.48.2

誘導放出枯渇顕微鏡法

STED顕微鏡

励起（3.1.49） 焦点（3.1.65） の空間分布の外側領域における励起分子の誘導放出によって 解像度（3.1.128） の向上が達成される，蛍光顕微鏡における超解像技術。音量

注記1:より高い解像度を達成するためには、誘導放出プロセスを可能な限り完全にする必要があります。すなわち、誘導放出は飽和する必要があります。

3.2.48.3

超解像構造化照明顕微鏡

優れた解像度

超解像SIM

構造化された照明顕微鏡法（3.2.47） では、回折限界によって与えられるよりも高い分解能で デジタル画像（3.2.13） を計算するために、パターン解像度が光学系の 回折限界（3.1.128.1） に近い （ 3.1.128.1)

注記 1:線形応答を使用する SIM は、最大で分解能限界の 2 倍を達成できますが、非線形応答を使用すると、分解能限界の 2 倍以上を達成できます。

3.2.49

タイムラプスイメージング

一定期間にわたって間隔をあけて 画像（3.1.75） を取得することに基づく画像化

3.2.50

全反射蛍光顕微鏡

TIRFM

蛍光（3.1.58） が、内部全反射によって生成されるエバネッセント波によって薄層で励起される顕微鏡法。

3.2.51

ホワイトバランス

対象物（3.1.104） の白色領域を画像内で白色として表示するための デジタル画像（3.2.13） or 電子画像（3.2.14） の色レベルの調整。

3.2.52

三次元再構築

オブジェクト（3.1.104） の三次元構造を表現するための二次元 デジタル（3.2.13） or 電子画像（3.2.14） の処理及び表示。

3.2.53

ライトシート顕微鏡

照明（3.1.73） が観察面内でのみ実現される顕微鏡技術

注記 1:ライト シート顕微鏡法は、ライト シートと標本を相対的に移動させることにより、固有の光学セクショニングを使用して 3D 画像を生成する機能を備えています。利点は、標本の露光量が減ることです。

3.2.54

デジタルホログラフィック顕微鏡

DEM

物体（3.1.104） から発生する波面情報がホログラムとしてデジタル的に記録され、そこから数値再構成アルゴリズムを使用して物体像が計算される顕微鏡法。

注記 1通常，信号波と参照波との干渉を利用して振幅情報と位相情報，ひいてはホログラムを得る。

3.2.55

光コヒーレンス顕微鏡

OCM

対象物内の反射面の相対的な深さを決定するために部分コヒーレント狭 走査（3.2.41） ビームを使用して、対象 物（3.1.104） の断面画像を取得するための光干渉測定技術。

注記 1:横方向の解像度は、走査光路内の光学系の特性であり、軸方向の解像度とは切り離されています。

注記 2:断面画像は、通常、集束ビームをサンプル全体にわたって横方向に走査することによって取得されます。ボリュメトリック画像は、一般に一連の断面画像によって取得されます。

[出典: ISO 16971:2015, 3.1, エントリに注記 1 と 2 を追加し、略語 OCM を追加するように修正。]

3.1.1

Abbe test plate

device for testing the chromatic (3.1.4.2) and spherical aberration (3.1.4.7) of microscope (3.1.99) objectives (3.1.106)

Note 1 to entry: When testing for spherical aberration, the cover glass thickness for which the objective is best corrected is also found. The test plate consists of a slide on which is deposited an opaque metal layer in the form of parallel strips arranged in groups of different width. The edges of these strips are irregularly serrated to allow the aberrations to be judged more easily. In its original and most common form, the slide is covered with a wedge-shaped cover glass, the increasing thickness of which is marked on the slide. Additional versions without the cover glass and/or with reflective stripes are also in use.

3.1.2

Abbe theory of image formation

explanation of the mechanism by which the microscope (3.1.99) image (3.1.75) is formed

3.1.3

aberration

<material and geometric form> deviation from perfect imaging by an optical system, caused by the properties of the material of the lenses (3.1.87) or by the geometric forms of the refracting or reflecting surfaces

3.1.4

aberration

<optical system> failure of an optical system to produce a perfect image (3.1.75)

3.1.4.1

astigmatism

aberration (3.1.4) which causes rays in one plane containing an off-axis object (3.1.104) point and the optical axis (3.1.107) to focus at a different distance from those in the plane at right angles to it

3.1.4.2

chromatic aberration

aberration (3.1.4) of a lens (3.1.87) or prism (3.1.119) , due to dispersion (3.1.47) by the material from which it is made

Note 1 to entry: This defect may be corrected by using a combination of lenses made from glasses or other materials of different dispersion.

3.1.4.2.1

axial chromatic aberration

aberration (3.1.4) by which light (3.1.88) of different wavelengths is focused at different points along the optical axis (3.1.107)

3.1.4.2.2

lateral chromatic aberration

chromatic difference of magnification

aberration (3.1.4) by which the images (3.1.75) formed by light (3.1.88) of different wavelengths, although they may be brought to the same focus (3.1.65) in the optical axis (3.1.107) , are of different sizes

3.1.4.3

coma

aberration (3.1.4) in which the image (3.1.75) of an off-axis point object (3.1.104) is deformed so that the image is shaped like a comet

3.1.4.4

curvature of image field

aberration (3.1.4) resulting in a curved image field (3.1.54.4) from a plane object field (3.1.54.5)

Note 1 to entry: Curvature of the image field is particularly obvious with objectives of high magnification and large numerical aperture, which have a restricted depth of field. It may largely be eliminated by additional correction.

3.1.4.5

distortion

aberration (3.1.4) in which lateral magnification (3.1.90.8) varies with distance from the optical axis (3.1.107) in the image field (3.1.54.4)

3.1.4.5.1

barrel distortion

negative distortion

difference in lateral magnification (3.1.90.8) between the central and peripheral areas of an image (3.1.75) such that the lateral magnification is less at the periphery

3.1.4.5.2

pincushion distortion

positive distortion

difference in lateral magnification (3.1.90.8) between the central and the peripheral areas of an image (3.1.75) such that the lateral magnification is greater towards the periphery

3.1.4.6

monochromatic aberrations

collective term for all aberrations (3.1.4) outside the Gaussian space which appear for monochromatic (3.1.123.2) light (3.1.88)

Note 1 to entry: The monochromatic aberrations are: spherical aberration, coma, astigmatism, curvature of image field and distortion.

3.1.4.7

spherical aberration

aberration (3.1.4) resulting from the spherical form of the wavefront arising from an object (3.1.104) point on the optical axis (3.1.107) , on its emergence from the optical system

Note 1 to entry: As a consequence, the rays emanating from an object point on the optical axis at different angles to the axis, or rays entering the lens parallel to the optical axis but at differing distances from it, intersect the optical axis in the image space before (undercorrection) or behind (overcorrection) the ideal image point formed by the paraxial rays.

3.1.5

achromat

<lens element> lens (3.1.87) in which the axial chromatic aberration (3.1.4.2.1) is corrected for two wavelengths

3.1.6

achromat

<microscope objective> microscope (3.1.99) objective (3.1.106) in which chromatic aberration (3.1.4.2) is corrected for two wavelengths and spherical aberration (3.1.4.7) and other aperture-dependent defects are minimized for one other wavelength which is usually about 550 nm

Note 1 to entry: This term does not imply any degree of correction for curvature of image field; coma and astigmatism are minimized for wavelengths within the achromatic range.

3.1.7

Airy pattern

image (3.1.75) of a primary or secondary point source (3.1.135.1) of light (3.1.88) which, due to diffraction (3.1.41) at a circular aperture (3.1.10) of an aberration-free lens (3.1.87) , takes the form of a bright disc surrounded by a sequence of concentric dark and bright rings

3.1.7.1

Airy disc

diffraction disc

central area bounded by the first dark ring of the Airy pattern (3.1.7)

Note 1 to entry: The Airy disc contains 84 % of the energy of the Airy pattern.

3.1.7.2

Airy unit

AU

diameter of the theoretical first minimum of the Airy pattern (3.1.7) in the low numerical aperture (3.1.10.4) approximation

3.1.8

anisotropic

having a non-uniform spatial distribution of properties

Note 1 to entry: In polarized light microscopy, this usually refers to the preferential orientation of optical properties with respect to the vibration plane of the polarized light.

3.1.9

apertometer

device for measuring the numerical aperture (3.1.10.4) of microscope (3.1.99) objectives (3.1.106)

3.1.10

aperture

area of a lens (3.1.87) which is available for the passage of light (3.1.88)

Note 1 to entry: In microscopy, it is usually expressed as the numerical aperture.

3.1.10.1

angular aperture

<microscopy>maximum plane angle subtended by a lens (3.1.87) at the centre of an object field (3.1.54.5) or image field (3.1.54.4) by two opposite marginal rays when the lens is used in its correct working position

Note 1 to entry: The term may be qualified by the side of the lens to which it refers (e.g. object side, illumination side, image side).

3.1.10.2

condenser aperture

illuminating aperture

aperture (3.1.10) of the illuminating system which is defined by the diameter of the illuminating aperture diaphragm (3.1.38.6)

3.1.10.3

imaging aperture

aperture (3.1.10) of the imaging system

Note 1 to entry: The imaging aperture is generally defined by the numerical aperture of the objective.

3.1.10.4

numerical aperture

na

number originally defined by Abbe for objectives (3.1.106) and condensers (3.1.28) , which is given by the expression n sin u, where n is the refractive index (3.1.125) of the medium between the lens (3.1.87) and the object (3.1.104) and u is half the angular aperture (3.1.10.1) of the lens

Note 1 to entry: Unless specified by “image-side”, the term refers to the object side.

3.1.11

aplanatic

corrected for spherical aberration (3.1.4.7) and coma (3.1.4.3)

3.1.12

apochromat

<lens element> lens (3.1.87) in which axial chromatic aberration (3.1.4.2.1) is corrected for three wavelengths

3.1.13

apochromat

<microscope objective> microscope (3.1.99) objective (3.1.106) in which the chromatic aberration (3.1.4.2) is corrected for three or more wavelengths and the spherical aberration (3.1.4.7) and other aperture-dependent defects are minimized for about 550 nm as with achromats (3.1.6)

Note 1 to entry: This term does not imply any degree of correction for curvature of image field.

Note 2 to entry: For more information see ISO 19012-2.

3.1.14

aspherical

not forming part of the surface of a sphere

Note 1 to entry: This term is also used to describe the shape of a refracting or a reflecting surface designed to minimize spherical aberration and some other aberrations.

3.1.15

beam splitter

means whereby a beam of light (3.1.88) may be divided into two or more separate beams

3.1.16

birefringence

Δn

quantitative expression of the maximum difference in refractive index (3.1.125) due to double refraction (3.1.48)

3.1.17

bright field

system of illumination (3.1.73) and imaging in which the direct light (3.1.45) passes through the objective (3.1.106) aperture (3.1.10) and illuminates the background against which the image (3.1.75) is seen

3.1.18

bulb

envelope of a lamp (3.1.85) , which is usually out of glass or fused silica

Note 1 to entry: This term is commonly used to describe the lamp itself.

3.1.19

catadioptric

having optical arrangements оr optical elements which operate by both reflection and refraction

3.1.20

catoptric

having optical arrangements оr optical elements which operate by reflection

3.1.21

centring telescope

auxiliary telescope

two-stage magnifier, designed for use in place of the eyepiece (3.1.52) to enable an image (3.1.75) of the back focal plane (3.1.62.1) of the objective (3.1.106) to be inspected

Note 1 to entry: The centring telescope is used principally for adjustment of the microscope illuminating system, especially with phase contrast and modulation contrast. It may also be used for conoscopic observation.

3.1.22

circle of least confusion

smallest diameter image (3.1.75) spot formed from a point object (3.1.104) when spherical aberration (3.1.4.7) and astigmatism (3.1.4.1) are present

3.1.23

clear focusing screen

sheet of clear glass or plastic material used for focusing (3.1.67) in photography and photomicrography (3.1.115) in which a figure on the screen (3.1.132) (e.g. cross lines) serves to define the plane (3.1.117) in which the aerial image (3.1.75.1) observed with a focusing magnifier (3.1.92.1) is located

3.1.24

coarse adjustment

focusing mechanism (3.1.68) designed to make large and rapid alterations in the distance along the optical axis (3.1.107) between the object (3.1.104) and the objective (3.1.106)

3.1.25

coating of optical surfaces

deposit of one or more thin dielectric and/or metallic layers on a surface of an optical element for the purpose of decreasing or increasing reflection and/or transmission

3.1.26

collector

lens (3.1.87) which serves to project a suitably sized image (3.1.75) of the source (3.1.135) into a given plane (3.1.117) [e.g. in Köhler illumination (3.1.73.3) into the apertureplane (3.1.117.1) of the condenser (3.1.28)]

Note 1 to entry: Sometimes known as the “lamp collector”.

3.1.27

compensator

retardation plate (3.1.130) of fixed or variable optical path length difference (3.1.108.1) used to measure the optical path length differences within an object (3.1.104)

Note 1 to entry: Many types of compensator exist, often designated by the name of their originator e.g. Babinet, Berek, Senarmont.

3.1.27.1

first-order red compensator

first-order red plate

sensitive tint plate

retardation plate (3.1.130) producing an optical path length difference (3.1.108.1) of one wavelength, giving rise to the interference colour (3.1.82) having the typical tint of the first-order red (3.1.57)

3.1.27.2

half-wave compensator

half-wave plate

retardation plate (3.1.130) producing an optical path length difference (3.1.108.1) of half a wavelength

3.1.27.3

quarter-wave compensator

quarter-wave plate

retardation plate (3.1.130) producing an optical path length difference (3.1.108.1) of a quarter of a wavelength

Note 1 to entry: The reference wavelength is selected according to the application and is individually indicated. When oriented at 45° to the plane of polarization, it changes plane-polarized light into circularly-polarized light and vice versa.

3.1.27.4

quartz-wedge compensator

retardation plate (3.1.130) consisting of a wedge of quartz (or two such wedges in the subtraction position) producing optical path length differences (3.1.108.1) continuously variable between 0 λ and 3 λ or 4 λ along its length

Note 1 to entry: This property results in the production of a series of interference colours in the form of fringes perpendicular to the length of the wedge. With monochromatic light, the coloured fringes are seen as alternating dark and bright bands.

3.1.28

condenser

part of the illuminating system of the microscope (3.1.99) which consists of one or more lenses (3.1.87) (or mirrors) and their mounts, usually containing a diaphragm (3.1.38) , and designed to collect, control and concentrate radiation (3.1.123) into the illuminating numerical aperture (3.1.10.4)

Note 1 to entry: In bright field microscopy by epi-illumination, the objective serves as its own condenser.

3.1.28.1

Abbe condenser

condenser (3.1.28) of simple design introduced by Abbe, in which there is only limited correction (3.1.33) for spherical aberration (3.1.4.7) and none for chromatic aberration (3.1.4.2)

3.1.28.2

achromatic-aplanatic condenser

condenser (3.1.28) in which chromatic aberrations (3.1.4.2) and spherical aberrations (3.1.4.7) have been reduced

Note 1 to entry: Achromatic-aplanatic correction is particularly advantageous for high numerical aperture, oil immersion condensers.

3.1.28.3

cardioid condenser

dark-field condenser (3.1.28.4) for transmitted-light illumination (3.1.73.6) , in which the correction (3.1.33) for spherical aberration (3.1.4.7) and coma (3.1.4.3) is calculated for a reflecting surface with the shape of a cardioid of revolution

Note 1 to entry: In practice, the correction is achieved by using a zone of a spherical surface which differs imperceptibly in its corrective effect from a true cardioid surface.

3.1.28.4

dark-field condenser

dark-ground condenser

condenser (3.1.28) designed for dark-field (3.1.35) microscopy

Note 1 to entry: For transmitted-light microscopy, this condenser is a separate component; for reflected-light microscopy, it is generally within the mount of the objective, surrounding the imaging system of the objective.

3.1.28.5

pancratic condenser

condenser (3.1.28) containing a variable “zoom” (pancratic) lens (3.1.87) which allows the size of the illuminated field (3.1.54.3) at the object (3.1.104) to be varied while the illuminated field diaphragm (3.1.38.5) remains of constant size

Note 1 to entry: The size of the illuminating aperture varies inversely with that of the illuminated field at the object, and the product of both sizes remains a constant.

3.1.28.6

phase-contrast condenser

condenser (3.1.28) designed for phase contrast (3.1.32.4) microscopy which forms on the phase plate (3.1.112) in the back focal plane (3.1.62.1) of the objective (3.1.106) a suitably sized image (3.1.75) of a diaphragm (3.1.38) (generally annular) positioned in the front focal plane (3.1.62.2) of the condenser

3.1.28.7

substage condenser

condenser (3.1.28) designed to fit beneath the stage (3.1.136) of a microscope (3.1.99)

3.1.28.8

swing-out top lens condenser

condenser (3.1.28) designed so that its top lens (3.1.87) can conveniently be removed from the optical path by operating a lever, thus increasing the condenser’s (3.1.28) focal length (3.1.61) in order to increase the area of the illuminated field (3.1.54.3) and decrease the illuminating numerical aperture (3.1.10.4) for use with objectives (3.1.106) of low magnification (3.1.90)

3.1.28.9

universal condenser

condenser (3.1.28) designed for multiple contrast techniques such as bright field (3.1.17) , dark-field (3.1.35) , phase contrast (3.1.32.4) , differential interference contrast (3.1.32.2.1) , polarized light (3.1.88.1) and modulation contrast (3.1.32.3)

3.1.29

conjugate planes

planes (3.1.117) perpendicular to the optical axis (3.1.107) which are imaged onto another in accordance with the rules of geometrical optics

3.1.30

conoscopic figure

interference pattern of curves linking points of equal retardation (3.1.129) , formed in the back focal plane (3.1.62.1) of the objective (3.1.106) when an optically anisotropic (3.1.8) object (3.1.104) is placed between crossed polars (3.1.118.2) or, exceptionally, parallel polars (3.1.118.3)

3.1.31

conoscopy

observation of the conoscopic figure (3.1.30) by means of a pinhole diaphragm (3.1.38) or a centring telescope (3.1.21) in place of the eyepiece (3.1.52) , or by means of a Bertrand lens (3.1.87.2)

3.1.32

contrast

distinction between regions in an image (3.1.75) due to differences in brightness and/or colour

3.1.32.1

interference contrast

<term> contrast (3.1.32) in the image (3.1.75) caused mainly by interference

3.1.32.2

interference contrast

<phenomenon> enhancing the contrast (3.1.32) between features having different optical path lengths (3.1.108)

3.1.32.2.1

differential interference contrast

contrast (3.1.32) due to double-beam interference (3.1.81.1) in which two waves which fall on the object plane (3.1.117.5) or image plane (3.1.117.3) are separated laterally by a distance similar to the minimum resolvable distance (3.1.128.2)

Note 1 to entry: This kind of contrast is characterized by an impression of unilateral oblique illumination. Variations in optical path length due to gradients in surface relief (reflected light) or in physical thickness or refractive index (transmitted light) appear as relief contrast in the image.

3.1.32.2.2

Nomarski differential interference contrast

form of differential interference contrast (3.1.32.2.1) using Nomarski prisms (3.1.119.2)

3.1.32.3

modulation contrast

contrast (3.1.32) technique due to Hoffman which uses a modulator in the back focal plane (3.1.62.1) of the objective (3.1.106) or in a succeeding conjugate plane (3.1.29) , and a slit aperture (3.1.10) in the front focal plane (3.1.62.2) of the condenser (3.1.28)

Note 1 to entry: The modulator is a filter composed of three regions: a dark region, a grey region onto which the slit in the condenser is imaged and a bright region. The modulator influences the direct light and diffracted light in order to increase contrast.

3.1.32.4

phase contrast

form of interference contrast (3.1.32.2) (in its widest sense) due to Zernike, in which the image contrast (3.1.32) of a phase object (3.1.111) is enhanced by altering phase (3.1.110) and amplitude of the direct light (3.1.45) with respect to those of the diffracted light (3.1.40) and which is achieved by the action of a phase plate (3.1.112) , usually in the form of an annulus, placed in the back focal plane (3.1.62.1) of the objective (3.1.106) (or in a succeeding plane conjugate (3.1.29) with this) conjugate with an appropriate illuminating aperture diaphragm (3.1.38.6) in the front focal plane (3.1.62.2) of the condenser (3.1.28)

Note 1 to entry: The phase plate has two properties: it shifts the phase of the direct light by 90° and absorbs some of its intensity. Contrast is achieved by conversion of phase differences within the light leaving the object into intensity differences in the image. Two kinds of phase contrast are available, depending on the characteristics of the phase plate; in positive phase contrast, objects which retard the phase of the diffracted light by a small amount appear darker than the background, while in negative phase contrast they appear brighter.

3.1.32.5

relief contrast

form of contrast (3.1.32) which presents gradients of geometrical or optical path length differences (3.1.108.1) in the object (3.1.104) in the form of a distribution of brightness in the image (3.1.75) which gives an impression of relief (3.1.126)

Note 1 to entry: This impression occurs because the distribution of brightness in a relief contrast image is similar to the distribution of light and shadow in the image of a three-dimensional object illuminated from one side.

3.1.33

correction

process whereby the aberrations (3.1.4) of an optical system are minimized

3.1.33.1

correction class

type of correction (3.1.33) of an optical system (achromatic, plan, etc.)

3.1.33.2

correction collar

mechanism provided on some objectives (3.1.106) in order to adapt their correction (3.1.33) for spherical aberration (3.1.4.7) to compensate for deviations from correct optical path length (3.1.108) in the cover glass (3.1.34) , wall of culture chamber and/or other media between the object (3.1.104) and the objective

3.1.33.3

correction for object to primary image distance

calculation of a microscope (3.1.99) objective (3.1.106) to optimize its corrections for a given standardized object to primary image (3.1.80.2.2) distance

3.1.33.4

overcorrection

error in the correction (3.1.33) of spherical aberration (3.1.4.7) , leading to lack of contrast (3.1.32) in the image (3.1.75)

Note 1 to entry: In microscopy it may be caused by the use of a cover glass thicker than, or a mechanical tube length longer than, the values assumed in the computation of the objective. The term may be used also in connection with other aberrations, e.g. chromatic aberration.

3.1.33.5

undercorrection

error in correction (3.1.33) of spherical aberration (3.1.4.7) , leading to lack of contrast (3.1.32) in the image (3.1.75)

Note 1 to entry: In microscopy, undercorrection may be caused by the use of a cover glass thinner than, or a mechanical tube length shorter than, the values assumed in the computation of the objectives. The term may be used also in connection with other aberrations, e.g. chromatic aberration.

3.1.34

cover glass

rectangular or circular piece of thin glass used to cover a microscopical preparation

Note 1 to entry: Because its thickness, refractive index and dispersion affect calculation and correction, the cover glass is regarded as part of the objective for the purpose of design. The tolerances of its thickness, refractive index and dispersion should be considered in relation to the demands of the objective, as standardized in ISO 8255-1.

3.1.35

dark-field

system of illumination (3.1.73) and imaging in which the direct light (3.1.45) is prevented from passing through the aperture (3.1.10) of the objective (3.1.106)

Note 1 to entry: The image is formed from light scattered by features in the object, the detail thus appearing bright against a dark background. It may be qualified as transmitted-light or reflected-light dark-field.

3.1.35.1

dark-field stop

central opaque disc usually used in the front focal plane (3.1.62.2) of a condenser (3.1.28) to occlude all the direct light (3.1.45) which would fall within the aperture (3.1.10) of the objective (3.1.106)

3.1.36

depth of field

<object space> axial depth of the space on both sides of the object plane (3.1.117.5) within which the object (3.1.104) can be moved without detectable loss of sharpness in the image (3.1.75) , while the positions of the image plane (3.1.117.3) and of the objective (3.1.106) are maintained

Note 1 to entry: See Note to 3.1.37.

3.1.37

depth of focus

<image space> axial depth of the space on both sides of the image (3.1.75) within which the image appears acceptably sharp, while the positions of the object plane (3.1.117.5) and of the objective (3.1.106) are maintained

Note 1 to entry: In some publications, the term “depth of focus” is used to refer to object space. It is recommended that, when the distinction is important, the full terms “depth of field (in object space)” and “depth of focus (in image space)” be used.

3.1.38

diaphragm

mechanical limitation of an opening normal to the optical axis (3.1.107) which restricts the cross-sectional area of the light (3.1.88) path at a defined place in an optical system and which may be fixed or variable in size, shape (although usually circular) and position

3.1.38.1

aperture diaphragm

diaphragm (3.1.38) in any aperture plane (3.1.117.1)

3.1.38.2

Bertrand diaphragm

field diaphragm (3.1.38.4) placed after a Bertrand lens (3.1.87.2) to restrict the field (3.1.54) from which a conoscopic figure (3.1.30) is formed

3.1.38.3

condenser diaphragm

diaphragm (3.1.38) which controls the effective size and shape of the condenser aperture (3.1.10.2) and which normally functions as the illuminating aperture diaphragm (3.1.38.6) in transmitted light

3.1.38.4

field diaphragm

diaphragm (3.1.38) in any field plane (3.1.117.2)

Note 1 to entry: Field diaphragms are usually fitted just after the lamp collector and in the eyepiece.

3.1.38.5

illuminated field diaphragm

field diaphragm (3.1.38.4) whose image (3.1.75) defines the illuminated field (3.1.54.3) at the object (3.1.104)

3.1.38.6

illuminating aperture diaphragm

aperture diaphragm (3.1.38.1) which defines the illuminating aperture (3.1.10.2) or the pupil (3.1.122) of an illuminating system

Note 1 to entry: For transmitted light, this is usually incorporated in the front focal plane of the condenser; in reflected-light microscopes it is found in the epi-illuminator in a plane conjugate with the back focal plane of the objective. It is commonly known simply as the “aperture diaphragm” or the “aperture stop”.

3.1.38.7

iris diaphragm

diaphragm (3.1.38) bounded by multiple leaves, usually metal, arranged so as to provide an opening of variable size, which is adjustable by means of a control

3.1.38.8

visual field diaphragm

diaphragm (3.1.38) which defines the field (3.1.54) of view and which is usually contained within the eyepiece (3.1.52)

3.1.39

dichromatic mirror

dichroic mirror

special type of interference filter (3.1.55.8) used as an essential part of a fluorescence microscope (3.1.99.5) using epi-illumination (3.1.73.2) and which is designed to reflect selectively the shorter wavelength exciting radiation (3.1.123) and transmit the longer wavelength fluorescence (3.1.58)

Note 1 to entry: A similar device is often used as a lamp reflector, in order to transmit the longer wavelength heat (infrared) radiation while reflecting the visible light.

3.1.40

diffracted light

light (3.1.88) which has undergone diffraction (3.1.41) at the object (3.1.104) and which gives rise to the first-order, second-order, etc. components of the diffraction pattern (3.1.41.1)

3.1.41

diffraction

phenomenon of deviation of the direction of propagation of light (3.1.88) or other wave motion when a wavefront passes any discontinuity in an object (3.1.104)

3.1.41.1

diffraction pattern

distribution of light (3.1.88) due to diffraction (3.1.41) , which depends on the geometrical and optical properties of the object (3.1.104) , the aberrations (3.1.3) of the lens (3.1.87) and the shape of its exit pupil (3.1.122) , and the wavelength of the light

3.1.41.1.1

primary diffraction pattern

primary diffraction image

diffraction pattern (3.1.41.1) of an object (3.1.104) which takes the form of multiple images (3.1.75) of the source (3.1.135)

Note 1 to entry: In Köhler illumination it is formed in the back focal plane of the objective.

3.1.42

diffraction grating

set of regularly repeating structures which, when illuminated, produce, by reflection or transmission, maxima and minima of intensity (3.1.79) as a consequence of diffraction (3.1.41) and interference

Note 1 to entry: These maxima and minima vary in position according to wavelength. Radiation of any given wavelength may thus be selected from complex radiation allowing the grating to be used for producing monochromatic light.

3.1.43

dioptre

unit of refractive power expressed as the reciprocal of the focal length (3.1.61) of a lens (3.1.87) in metres

3.1.44

dioptric

describing optical arrangements or optical elements which operate by refraction, i.e. using lenses (3.1.87)

3.1.45

direct light

light (3.1.88) which enters the objective (3.1.106) after undergoing no change in direction of propagation on passing through the object field (3.1.54.5) (transmitted light), or on specular reflection at a flat surface in the object field oriented normally to the direction of propagation of the light (reflected light)

3.1.46

dispersion

<wave group> change in phase velocity of a wave group as a function of its wavelength (or frequency) when passing from one medium to another which causes a separation of the monochromatic components of a complex radiation (3.1.123)

3.1.47

dispersion

<refractive index> variation in refractive index (3.1.125) of a medium which causes a separation of the monochromatic components of a complex radiation (3.1.123)

Note 1 to entry: The quantity characterizing this property may have a special name, e.g. the Abbe number, or the dispersive power, of the medium.

3.1.47.1

dispersion curve

graph of refractive index (3.1.125) of a medium as a function of wavelength or a related parameter, at a given temperature

3.1.48

double refraction

effect of anisotropy, by which electromagnetic waves are divided into plane-polarized (3.1.88.1.2) components having mutually perpendicular vibration directions and being propagated with different velocities

Note 1 to entry: Double refraction may be due to structure, orientation of particles, or strain. The quantitative expression of double refraction is birefringence.

3.1.49

excitation

input of energy to matter leading to the emission of radiation (3.1.123)

3.1.50

exposure

total quantity of light (3.1.88) allowed to fall upon a photosensitive emulsion which is measured in lux per second

3.1.50.1

exposure meter

device for determining the required exposure (3.1.50) for photographic materials

3.1.51

extinction

condition in which an optically anisotropic object (3.1.104) appears dark when observed between crossed polars (3.1.118.2)

3.1.52

eyepiece

lens (3.1.87) system in a separate mount, which magnifies the microscope’s (3.1.99) final real image (3.1.75.3) , formed in a viewing tube (3.1.144.6) , and projects it to infinity or to a distance comfortable for viewing by the human eye

3.1.52.1

compensating eyepiece

eyepiece (3.1.52) designed to correct residual aberrations of the objective (3.1.106) ,

3.1.52.2

external-diaphragm eyepiece

eyepiece (3.1.52) in which the field diaphragm (3.1.38.4) is located in front of the lenses (3.1.87)

Note 1 to entry: This type of eyepiece is suitable for the insertion of graticules.

3.1.52.3

filar eyepiece

micrometer-screw eyepiece

micrometer eyepiece (3.1.52.9) in which reference marks in the primary image plane (3.1.117.4) may be adjusted by means of a micrometer screw and the resultant indicated displacement is used to derive dimensions

3.1.52.4

focusable eyepiece

eyepiece (3.1.52) with a mechanism to focus on a graticule (3.1.70) or field diaphragm (3.1.38.4) mounted within it

3.1.52.5

high-eyepoint eyepiece

eyepiece (3.1.52) computed so that the exit pupil of the microscope (3.1.122.2) is sufficiently far from the eye lens (3.1.87.3.) to facilitate use of the microscope (3.1.99) by wearers of spectacles and/or for special applications

3.1.52.6

Huygens eyepiece

term originally used for an eyepiece (3.1.52) consisting of two planoconvex lenses (3.1.87) (the field lens (3.1.87.4) and the eye lens (3.1.87.3) ) mounted with their convex sides facing the objective (3.1.106) and with the field diaphragm (3.1.38.4) between them

3.1.52.7

internal-diaphragm eyepiece

eyepiece (3.1.52) in which the field diaphragm (3.1.38.4) is located between the field lens (3.1.87.4) and the eye lens (3.1.87.3)

3.1.52.8

Kellner eyepiece

improved type of Ramsden eyepiece (3.1.52.11) in which the distances between the field lens (3.1.87.4) and the diaphragm (3.1.38) , and from the eye lens (3.1.87.3) to the exit pupil of the microscope (3.1.122.2) , are both increased

3.1.52.9

micrometer eyepiece

focusable eyepiece (3.1.52.4) used for measuring

Note 1 to entry: In its most common form, a measuring graticule is fitted in the primary image plane. It is calibrated against a stage micrometer.

3.1.52.10

pointer eyepiece

eyepiece (3.1.52) containing a pointer in its primary image plane (3.1.117.4)

3.1.52.11

Ramsden eyepiece

eyepiece (3.1.52) consisting of two planoconvex lenses (3.1.87) of the same focal length (3.1.61) [the field lens (3.1.87.4) and the eye lens (3.1.87.3) ], mounted with their convex sides together and separated by a distance equal to the focal length of the lenses

3.1.52.12

widefield eyepiece

eyepiece (3.1.52) specially computed to provide a field (3.1.54) of view greater than that of a normal eyepiece of the same magnification (3.1.90)

3.1.53

eyepoint height

eye relief

distance measured along the optical axis (3.1.107) from the last surface of the eyepiece (3.1.52) to the exit pupil of the microscope (3.1.122.2) where the eye is located

Note 1 to entry: Its value may be affected by optical systems which are inserted between objective and eyepiece.

3.1.54

field

area in the object plane (3.1.117.5) or any other plane conjugate (3.1.29) with it

Note 1 to entry: The term may be qualified by its location (e.g. object field, image field) or its function (e.g. illuminated field, photometric field).

3.1.54.1

eyepiece field of view

part of the primary image (3.1.75.2) which is defined by the field diaphragm (3.1.38.4) of the eyepiece (3.1.52)

3.1.54.2

field-of-view number

field number

FN

number which specifies the eyepiece field of view (3.1.54.1) and which is the actual diameter in millimetres of the field diaphragm (3.1.38.4) in an external-diaphragm eyepiece (3.1.52.2) or the apparent diameter of the virtual image (3.1.75.4) of the field diaphragm (3.1.38.4) in an internal-diaphragm eyepiece (3.1.52.7)

Note 1 to entry: The field-of-view number is now one of the standard markings of the eyepiece and may be used to calculate the diameter of the microscope field of view (object field).

3.1.54.3

illuminated field

part of the object field (3.1.54.5) which receives illumination (3.1.73)

3.1.54.4

image field

any field (3.1.54) in which an image (3.1.75) of the object (3.1.104) is formed

3.1.54.5

object field

microscope field of view

FOV

3.1.54.6

objective field number

OFN

maximum field-of-view number (3.1.54.2) of the eyepiece (3.1.52) for which the objective (3.1.106) is designed to be used

3.1.55

filter

optical device designed to control selectively the wavelengths, colour temperature, vibration direction, and/or intensity (3.1.79) of the radiation (3.1.123) which it transmits or reflects

3.1.55.1

barrier filter

filter (3.1.55) used in fluorescence microscopy which is designed to prevent the passage towards the image (3.1.75) of those wavelengths of light (3.1.88) used for excitation (3.1.49) but to allow the light produced by fluorescence (3.1.58) of the object (3.1.104) to pass

3.1.55.2

broad-band-pass filter

broad-band filter

filter (3.1.55) which allows the passage of radiation (3.1.123) with a broad wavelength band (greater than about 50 nm) around a given central wavelength

Note 1 to entry: The concept of a “broad” band is arbitrary.

3.1.55.3

colour filter

filter (3.1.55) which allows the passage of light (3.1.88) of selected colour (chromaticity) or wavelength characteristics

3.1.55.4

colour-conversion filter

conversion filter

filter (3.1.55) used to change the colour temperature of light (3.1.88) received from a source (3.1.135)

3.1.55.5

contrast filter

filter (3.1.55) used to adjust the contrast (3.1.32) in an image (3.1.75) between features of an object (3.1.104) or between the object and the background

3.1.55.6

exciter filter

filter (3.1.55) used in fluorescence microscopy designed (ideally) to pass only those wavelengths which excite fluorescence (3.1.58)

3.1.55.7

heat filter

heat protection filter

filter (3.1.55) designed to prevent the passage of radiation (3.1.123) in the infrared or near infrared ranges

3.1.55.8

interference filter

filter (3.1.55) designed to transmit or reflect selectively a limited part of the spectrum by multiple-beam interference (3.1.81.3)

3.1.55.9

long-wave-pass filter

long-pass filter

filter (3.1.55) designed to allow the passage of radiation (3.1.123) of wavelengths longer than a given limit

3.1.55.10

narrow-band-pass filter

narrow-band filter

filter (3.1.55) (often an interference filter (3.1.55.8) ) which allows the passage of radiation (3.1.123) only within a very narrow wavelength band around a given central wavelength

Note 1 to entry: The concept of a “narrow” band is arbitrary.

3.1.55.11

neutral-density filter

ND filter

neutral filter

filter (3.1.55) designed to reduce as equally as possible the intensity (3.1.79) of radiation (3.1.123) across the whole visible spectrum

3.1.55.12

polarizing filter

filter (3.1.55) acting as a polar (3.1.118) by total or partial absorption of light (3.1.88) vibrating in certain directions

3.1.55.13

short-wave-pass filter

short-pass filter

filter (3.1.55) designed to allow the passage of radiation (3.1.123) of wavelengths shorter than a given limit

3.1.56

fine adjustment

focusing mechanism (3.1.68) designed to make small and precise alterations in the relative positions along the optical axis (3.1.107) between the object (3.1.104) and the objective (3.1.106)

Note 1 to entry: The precision of positioning which it provides should be better than the depth of field of the objective.

3.1.57

first-order red

sensitive tint

characteristic reddish-violet interference colour (3.1.82) selected from light (3.1.88) of a continuous spectrum by the extinction (3.1.51) of other wavelengths

3.1.58

fluorescence

phenomenon of selective absorption of radiation (3.1.123) of relatively short wavelength (i.e. of relatively high energy) by matter, resulting in the emission of radiation of longer wavelengths (i.e. of lower energy), persisting for only a very short time after the cessation of the excitation (3.1.49)

Note 1 to entry: In the special case of multiple-photon excitation, longer wavelength (lower energy) radiation may excite fluorescence with the effect of radiation of shorter wavelength.

3.1.58.1

primary fluorescence

autofluorescence

fluorescence (3.1.58) exhibited by virtue of the inherent properties of an object (3.1.104)

3.1.58.2

secondary fluorescence

fluorescence (3.1.58) exhibited by an object (3.1.104) after treatment with a fluorochrome (3.1.60)

3.1.58.3

excitation wavelength

specific wavelength of light (3.1.88) required to excite a fluorochrome (3.1.60) , such as a fluorescent antibody or fluorescent protein, to emit light at emission wavelengths

3.1.58.3.1

excitation wavelength band

specific wavelength range of light (3.1.88) used to excite a fluorochrome (3.1.60)

3.1.58.4

detection wavelength band

specific wavelength range of light (3.1.88) collected by the photo detector

3.1.59

fluorite

crystalline calcium fluoride (CaF₂)

Note 1 to entry: This material, or others with similar optical properties, is used as an additional lens material for the correction of chromatic aberration and improvement in light transmission in some microscope objectives of the higher correction classes.

3.1.60

fluorochrome

substance used to impart fluorescence (3.1.58) to structures within a specimen for subsequent examination by fluorescence microscopy (3.1.99.5)

3.1.61

focal length

forf'

distance measured along the optical axis from the principal plane (3.1.117) of a lens (3.1.87) to the appropriate focal plane (3.1.62)

3.1.62

focal plane

surface in which bundles of parallel rays are brought to a point by an ideal lens (3.1.87)

3.1.62.1

back focal plane

<converging lens> focal plane (3.1.62) of a lens (3.1.87) which lies behind it when viewed in the direction of passage of light (3.1.88)

3.1.62.2

front focal plane

<converging lens> focal plane (3.1.62) of a lens (3.1.87) which lies in front of it when viewed in the direction of the passage of light (3.1.88)

3.1.63

focal point

ForF'

point of intersection of the focal plane (3.1.62) with the optical axis (3.1.107) , and where rays entering an ideal lens (3.1.87) parallel to the optical axis cross the optical axis (converging lens) or appear to originate from (diverging lens)

3.1.64

focus

<lens> focal point (3.1.63) of a lens (3.1.87)

3.1.65

focus

<imaging> state of sharpest imaging

3.1.66

focus

<ray tracing> point in the object plane (3.1.117.5) at which those rays intersect which, after refraction and/or reflection in an optical system also intersect in the image plane (3.1.117.3) to give rise to a sharp image (3.1.75) of the conjugate point

3.1.67

focusing

<control> act of bringing the optical system into focus (3.1.65) , i.e. bringing it to the position at which it forms an image (3.1.75) of the utmost sharpness in the proper image plane (3.1.117.3)

Note 1 to entry: In accordance with the character of the focusing mechanism used for this, the word may be qualified by the adjective “coarse” or “fine”.

3.1.68

focusing mechanism

mechanism used to change the distance between the object (3.1.104) and the optical system forming an image (3.1.75) , with the purpose of obtaining maximum sharpness in that image

Note 1 to entry: In the case of the microscope, the focusing mechanism (3.1.68) is often mediated by a rack and pinion and converts the rotary motion of a knob into linear motion along the optical axis (3.1.107) of either the objective (3.1.106) (with or without the tube (3.1.144) ) or the stage (3.1.136) .

3.1.69

free working distance

working distance

WD

distance in air, or in the specified immersion liquid (3.1.78) , between the front of the objective (3.1.106) and the surface of the cover glass (3.1.34) , or of the object (3.1.104) if uncovered, under normal operating conditions

3.1.70

graticule

reticle

pattern such as a scale or grid, together with its support, placed in an object plane (3.1.117.5) or an image plane (3.1.117.3) which is used for measurement, reference, alignment, location, counting or stereological analysis

3.1.71

ground glass

glass whose surface is roughened by mechanical or chemical means, used in microscopy to provide scattering or diffusion of the light (3.1.88) passing through or falling on it

Note 1 to entry: It may be used as a screen for the visualization of a real image.

3.1.72

halo

phenomenon in phase contrast (3.1.32.4) microscopy by which a feature in the image (3.1.75) is surrounded by a dark or light rim

3.1.73

illumination

application of light (3.1.88) to an object (3.1.104)

3.1.73.1

axial illumination

illumination (3.1.73) with a ray bundle whose axis coincides with the optical axis (3.1.107) of the microscope (3.1.99)

3.1.73.2

epi-illumination

coaxial light

reflected light

incident light

vertical illumination

illumination (3.1.73) which falls on the object field (3.1.54.5) from the same side as that from which the object field is observed

3.1.73.3

Köhler illumination

method of illuminating microscopical objects (3.1.104) , providing a uniformly illuminated field (3.1.54.3) from a non-uniform source (3.1.135)

Note 1 to entry: An image of the source is projected by a collector into the plane of the aperture diaphragm in the front focal plane of the condenser. The condenser, in turn, projects an image of an illuminated field diaphragm at the opening of the collector into the object plane. In the reflected-light microscope, where the objective serves as its own condenser, an aperture diaphragm is imaged by a relay lens into the back focal plane of the objective and the illuminated field diaphragm is arranged to be in a plane conjugate with that of the collector.

3.1.73.4

oblique illumination

illumination (3.1.73) using a ray bundle whose axis makes an angle with the optical axis (3.1.107) of the microscope (3.1.99)

3.1.73.5

source-focused illumination

critical illumination

method of illumination (3.1.73) in which an image (3.1.75) of the source (3.1.135) , which may carry an illuminated field diaphragm (3.1.38.5) , is projected by the condenser (3.1.28) into the object plane (3.1.117.5)

Note 1 to entry: Even illumination is obtained from a homogeneous source.

3.1.73.6

transmitted-light illumination

trans-illumination

diascopic illumination

illumination (3.1.73) which passes through the object field (3.1.54.5) from the opposite side to that from which the object field is observed

3.1.74

illuminator

device designed to provide illumination (3.1.73)

3.1.74.1

epi-illuminator

part of the illuminating system of the reflected-light microscope (3.1.99.11) placed between the objective (3.1.106) [which serves as its own condenser (3.1.28) ] and the lamp fitting

Note 1 to entry: The epi-illuminator is attached to or is inserted into the body tube, thus forming a section of this tube. A reflector, or a set of interchangeable reflectors, is included in the illuminator.

3.1.74.2

fibre optic illuminator

illuminating system in which the light (3.1.88) is delivered by a fibre optic

3.1.75

image

collection of points formed by a lens (3.1.87) or other imaging system, corresponding to points in the object (3.1.104)

Note 1 to entry: The image is a structural representation of those properties of the object which cause modulation of light. All parameters which describe the spatial and the temporal state of light can be modulated. Because of these modulations, the light in an encoded form carries the information about the object. In microscopy with the compound microscope, a primary image and a secondary image are formed, the latter being produced on the retina of the observer’s eye, on photographic material or on another surface.

3.1.75.1

aerial image

real image (3.1.75.3) existing in a plane (3.1.117) in space and not normally visible to the naked eye

3.1.75.2

primary image

usually magnified real image (3.1.75.3) of the object (3.1.104) formed by the objective (3.1.106) or, in infinity-corrected systems, by the objective together with its tube lens (3.1.87.10)

Note 1 to entry: The “primary image” is not to be confused with the “primary interference image” as described by Abbe.

3.1.75.3

real image

image (3.1.75) which can be received on a surface

3.1.75.4

virtual image

image (3.1.75) which cannot be received on a surface but which may be converted into a real image (3.1.75.3) by the optical system of the eye or other converging lens (3.1.87) system

3.1.76

image space

space on that side of an optical system where the image (3.1.75) is located

Note 1 to entry: In reflection or formation of a virtual image, this space may coincide with the object space.

3.1.77

immersion

use of an immersion liquid (3.1.78)

3.1.77.1

homogeneous immersion

immersion (3.1.77) in which the immersion liquid (3.1.78) and the adjacent optical components have the same refractive index (3.1.125) and dispersion (3.1.47) (or Abbe number) so that neither refraction nor reflection occurs between the liquid and the optical components

Note 1 to entry: In modern microscope design, refractive index differences between objective front lens, the immersion liquid and the cover glass may be deliberately introduced in order to assist in the correction of the system, so that the immersion is not truly homogeneous.

3.1.77.2

oil immersion

immersion (3.1.77) in which the immersion liquid (3.1.78) is immersion oil (3.1.78.1)

3.1.78

immersion liquid

liquid specified as suitable for use in the space between the front of an immersion lens (3.1.87.6) and the object (3.1.104)

Note 1 to entry: Because the immersion liquid is considered in the computing of corrections to be part of the lens, its refractive index and dispersion (or Abbe number) are critical.

3.1.78.1

immersion oil

synthetic immersion liquid (3.1.78)

Note 1 to entry: The term was formerly applied to naturally occurring immersion liquids such as cedar-wood oil.

Note 2 to entry: Immersion oil is according to ISO 8036.

3.1.79

intensity

general term for the strength of a radiation (3.1.123) , which is proportional to the square of the amplitude of the electromagnetic wave

Note 1 to entry: For measurement, this term should be replaced by the most suitable photometric or radiometric quantity.

3.1.80

interfacing dimensions

mechanical or opto-mechanical distances measured from reference planes (3.1.117.6) , on which the calculation of microscope (3.1.99) lenses (3.1.87) and the design of microscopes are based, and which facilitate the interchange of certain components

Note 1 to entry: There are two categories of dimensions: those which are standardized internationally and others which are taken as internal standards by individual manufacturers.

3.1.80.1

mechanical interfacing dimensions of the microscope

distances between several mechanical locating surfaces (3.1.89) or flanges

3.1.80.2

optical interfacing dimensions of the microscope

distances of focal points (3.1.63) , or object planes (3.1.117.5) or image planes (3.1.117.3) , from mechanical locating surfaces (3.1.89) or flanges

3.1.80.2.1

objective to primary image distance

distance in air between the objective locating surface of the nosepiece (3.1.89.3) and the primary image plane (3.1.117.4)

Note 1 to entry: The objective to primary image distance is one of the optical interfacing dimensions and commonly has a value of either 150 mm or infinity. The latter is a hypothetical value applied to microscopes designed for infinity-corrected objectives.

3.1.80.2.2

object to primary image distance

distance in air between the object plane (3.1.117.5) and the primary image plane (3.1.117.4)

Note 1 to entry: The object to primary image distance is the fundamental optical interfacing dimension used in microscope design and commonly has a value of either 195 mm or infinity. The latter is a hypothetical value applied to microscopes designed for infinity-corrected objectives.

3.1.80.2.3

parfocalizing distance of the eyepiece

distance between the locating flange of the eyepiece (3.1.89.1) and the plane (3.1.117) upon which the eyepiece (3.1.52) is focused

Note 1 to entry: The plane upon which the eyepiece is focused is coincident with the plane of the final real image of the microscope when the eyepiece is mounted in the viewing tube. The parfocalizing distance of the eyepiеce is one of the optical interfacing dimensions, and is commonly 10 mm.

3.1.80.2.4

parfocalizing distance of the objective

distance in air between the object plane (3.1.117.5) [i.e. the uncovered surface of the object (3.1.104) ] and the locating flange of the objective (3.1.89.4) , when the microscope (3.1.99) is in its working position

Note 1 to entry: The parfocalizing distance of the objective is one of the optical interfacing dimensions.

3.1.81

interference

mutual interaction between two or more coherent wave trains

Note 1 to entry: The phenomenon may be used to convert optical path length differences in the object into intensity variations in the image so providing contrast.

3.1.81.1

double-beam interference

interference between wave trains from two coherent light (3.1.88) beams

3.1.81.2

double-focus interference

double-beam interference (3.1.81.1) in which the two light (3.1.88) beams have different levels of focus (3.1.65) and in which one beam is focused in the object plane (3.1.117.5) , the other above or below that plane

3.1.81.3

multiple-beam interference

interference between wave trains from more than two coherent light (3.1.88) beams

3.1.81.4

polarizing interference

double-beam interference (3.1.81.1) in which the two light (3.1.88) beams arise from one plane-polarized (3.1.88.1.2) beam as the result of double refraction (3.1.48) , are plane-polarized in mutually perpendicular vibration directions and are recombined by the analyser (3.1.118.1)

3.1.81.5

shearing interference

double-beam interference (3.1.81.1) in which the two light (3.1.88) beams falling upon the object plane (3.1.117.5) or image plane (3.1.117.3) are separated laterally from one another

Note 1 to entry: This separation limits the size of features which can be studied.

3.1.82

interference colour

mixed colour resulting from extinction (3.1.51) or partial extinction, caused by interference, of one or several parts of the spectrum

3.1.83

interferometry

interference phenomena applied to the measurement of optical path length differences (3.1.108.1) , from which refractive indices and thickness can also be derived

3.1.84

interpupillary distance

distance in millimetres between the centres of the pupils of a person's eyes when viewing with parallel fixation lines

Note 1 to entry: Binocular microscopes and binocular tubes are provided with an adjustment to allow for the variable interpupillary distances of different people.

3.1.85

lamp

source of radiation (3.1.123)

3.1.85.1

filament lamp

lamp (3.1.85) from which radiation (3.1.123) is emitted from a filament, usually of tungsten, heated by the passage of an electric current

Note 1 to entry: The emitted spectrum is continuous and approximates to that of a black-body radiator.

3.1.85.2

halogen lamp

filament lamp (3.1.85.1) whose envelope contains halogen vapour

Note 1 to entry: A cyclical process in which the halogen reduces loss of tungsten from the filament and its deposition on the envelope. This permits a high filament temperature and consequent higher luminance, higher colour temperature and longer operating life than a conventional filament lamp of the same input power.

3.1.85.3

mercury arc lamp

discharge lamp (3.1.85) containing mercury vapour, often at a high pressure when the lamp is operating

Note 1 to entry: At low pressure the lamp emits a characteristic line spectrum but when it heats up there is a strong continuous spectrum forming the background. This type of lamp is frequently used in fluorescence microscopy and also, with a suitable filter, as a source of monochromatic radiation or ultraviolet radiation.

3.1.85.4

microscope lamp

lamp (3.1.85) together with its collector (3.1.26) , mirror, housing and fittings

Note 1 to entry: The microscope lamp may be incorporated into the microscope stand itself, or be a separate unit.

3.1.85.5

xenon arc lamp

discharge lamp (3.1.85) containing xenon, often at a high pressure when the lamp is operating

Note 1 to entry: The lamp emits light of high luminance, high colour temperature and with an almost continuous spectrum distributed from the ultraviolet to the infrared.

3.1.86

laser

source which emits coherent radiation (3.1.123) of high spectral concentration of radiance and an extremely small solid angle

Note 1 to entry: Acronym for Light Amplification by Stimulated Emission of Radiation.

3.1.87

lens

piece of transparent material with one or more curved surfaces, which is used to alter systematically the direction of rays of light (3.1.88)

Note 1 to entry: The term may also be used for a system of lenses which, in principle, acts as a single lens.

3.1.87.1

aspherical lens

lens (3.1.87) made with an aspherical (3.1.14) surface

3.1.87.2

Bertrand lens

Amici-Bertrand lens

intermediate lens (3.1.87.7) which transfers an image (3.1.75) of the back focal plane (3.1.62.1) of the objective (3.1.106) into the primary image plane (3.1.117.4)

Note 1 to entry: The Bertrand lens is used for conoscopic observation in polarized-light microscopy and for adjustment of the microscope illuminating system, especially in phase-contrast and modulation-contrast microscopy.

3.1.87.3

eye lens

lens (3.1.87) or group of lenses of an eyepiece (3.1.52) nearest to the observer's eye

3.1.87.4

field lens

lens (3.1.87) positioned in or close to a field plane (3.1.117.2) in order to adapt the exit pupil (3.1.122) of the preceding lenses to the entrance pupil of subsequent lenses

Note 1 to entry: Use of field lenses suppresses vignetting in the image and, more generally, provides homogeneous illumination of the field to which it relates. The term is often used without qualification to describe the field lens of the eyepiece.

3.1.87.5

gradient-index lens

lens (3.1.87) in which some or all of the refractive power results from axial, radial or spherical variation in refractive index (3.1.125)

3.1.87.6

immersion lens

objective (3.1.106) or condenser (3.1.28) designed to work with an immersion liquid (3.1.78)

3.1.87.7

intermediate lens

lens (3.1.87) located between the objective (3.1.106) and the primary image (3.1.75.2) which serves to control the position and/or lateral magnification (3.1.90.8) of the primary image, and/or to ensure the conditions for correct optical imaging if the actual optical interfacing dimensions (3.1.80.2) are different from the standard ones

3.1.87.8

photographic projection lens

projection lens (3.1.121) specially designed for photomicrography (3.1.115)

3.1.87.9

relay lens

lens (3.1.87) for transferring an image (3.1.75) into another plane (3.1.117)

3.1.87.10

tube lens

intermediate lens (3.1.87.7) designed to operate as an essential component of infinity-corrected objectives (3.1.106.3) , and which should be regarded as part of the objective lens system when magnification and correction (3.1.33) are considered

3.1.87.10.1

normal tube lens

particular tube lens (3.1.87.10) with which an infinity-corrected objective (3.1.106.3) is designed to operate

3.1.87.10.2

focal length of the normal tube lens

f_NTL

focal length(3.1.61) related to the magnification (3.1.90) and the focal length of the objectives (3.1.106) which are designed to operate with this tube lens (3.1.87.10)

3.1.87.11

tubelength correction lens

intermediate lens (3.1.87.7) used to correct optically any deviation of mechanical tubelength from its nominal value

3.1.88

light

electromagnetic radiation (3.1.123) directly capable of causing a visual sensation

3.1.88.1

polarized light

light (3.1.88) in which the vibrations are partially or completely suppressed in certain directions at any given instant

Note 1 to entry: The vector of vibration may describe a linear, circular or elliptical shape.

3.1.88.1.1

elliptically-polarized light

polarized light (3.1.88.1) in which the vector of vibration describes an elliptical shape

3.1.88.1.2

plane-polarized light

linear-polarized light

polarized light (3.1.88.1) in which the vector of vibration describes a linear shape

3.1.88.2

stray light

light (3.1.88) which arises from scatter or reflection by the object (3.1.104) , in lenses (3.1.87) , or by obstacles in the light path, and which does not contribute to image (3.1.75) formation and reduces the contrast (3.1.32) in the image

3.1.89

locating surface

locating flange

surface at which two interchangeable components fit together

Note 1 to entry: These surfaces are perpendicular to the optical axis and are responsible for setting the correct axial location and centration of the optical and mechanical elements. They may coincide with reference planes for optical interfacing dimensions.

3.1.89.1

locating flange of eyepiece

flange on the eyepiece (3.1.52) which locates it at a given level which is the eyepiece-locating surface of viewing tube (3.1.89.2)

Note 1 to entry: The locating flange of eyepiece is one of the reference planes for the parfocalizing distance of the eyepiece.

3.1.89.2

eyepiece-locating surface of viewing tube

surface at the upper end of the viewing tube (3.1.144.6) which sets the level of the locating flange of eyepiece (3.1.89.1)

Note 1 to entry: The eyepiece-locating surface of viewing tube is one of the reference planes which determines the mechanical tube length.

3.1.89.3

objective-locating surface of the nosepiece

surface of the nosepiece (3.1.103) which locates the objective (3.1.106) at a given level and is coincident with the locating flange of the objective (3.1.89.4)

Note 1 to entry: The objective-locating surface is one of the reference planes determining the mechanical tube length, the parfocalizing distance of the objective, and the objective to primary image distance.

3.1.89.4

locating flange of the objective

objective shoulder

surface of an objective (3.1.106) which locates it at a given level which is the objective-locating surface of the nosepiece (3.1.89.3)

Note 1 to entry: The locating flange of the objective is one of the reference planes determining the mechanical tube length and parfocalizing distance of the objective.

3.1.90

magnification

process of changing the apparent dimensions of an object (3.1.104) by optical techniques, or the numerical expression of the result of this

Note 1 to entry: The type of magnification such as visual or lateral should always be specified.

Note 2 to entry: The more general term magnifying power as a measure of the ability of an optical system to produce visual magnification and lateral magnification under specified operating conditions has been replaced in this document by “magnification”, due to the more established use of this term in practical work.

3.1.90.1

magnification of an eyepiece

M_E

visual magnification (3.1.90.10) at the virtual image (3.1.75.4) formed from the primary image (3.1.75.2) by the eyepiece (3.1.52)

3.1.90.2

total magnification of a microscope used to produce a real image

M_{TOT PROJ}

lateral magnification (3.1.90.8) at the real image (3.1.75.3)

3.1.90.3

total visual magnification of a microscope used for visual observation

M_{TOT VIS}

visual magnification (3.1.90.10) at the virtual image (3.1.75.4) formed by the microscope (3.1.99)

3.1.90.4

magnification of an objective with finite primary image distance

M_O

lateral magnification (3.1.90.8) at the primary image (3.1.75.2) formed at the distance from the objective (3.1.106) specified in the design of the objective

Note 1 to entry:M_O should be expressed in proportional form, e.g. 10:1.

3.1.90.5

magnification of an objective with infinite primary image distance, in combination with the normal tube lens

M_O∞

lateral magnification (3.1.90.8) at the real image (3.1.75.3) produced by the combination of the objective (3.1.106) and the normal tube lens (3.1.87.10.1) (the tube lens with which the objective is designed to operate)

3.1.90.6

axial magnification

ratio between a given axial distance in image space (3.1.76) and the corresponding distance in object space (3.1.105)

3.1.90.7

empty magnification

magnification (3.1.90) greater than the useful range of magnification (3.1.90.9)

Note 1 to entry: Exceeding the range of useful magnification gives no further information about the object, but sharpness and contrast appear to decrease.

3.1.90.8

lateral magnification

ratio of a given distance in the real image (3.1.75.3) normal to the optical axis (3.1.107) to the corresponding distance in the object (3.1.104)

Note 1 to entry: This ratio should be expressed in proportional form, e.g. 10:1.

3.1.90.9

useful range of magnification for visual observation

range of total visual magnifications (3.1.90.3) within which details in the object (3.1.104) are clearly seen in the image (3.1.75)

Note 1 to entry: The value of this range is usually taken to lie between 500 and 1 000 times the numerical aperture of the objective. When the total visual magnification is less than the lower limit, the resolving power of the objective cannot be fully utilized; when the total visual magnification exceeds the upper limit, empty magnification occurs. This phenomenon is due to the resolving properties of the eye, generally assumed to be between 2 and 4 minutes of arc.

3.1.90.10

visual magnification

ratio of the tangent of the viewing angle (3.1.147) of the object (3.1.104) when observed through a magnifying system with the image (3.1.75) at infinity, to that of the object when observed by the naked eye at the reference viewing distance (3.1.124) (250 mm)

Note 1 to entry: This ratio should be expressed in numerical form with the multiplication sign, e.g. ×10.

3.1.91

magnification changer

intermediate lens (3.1.87.7) for changing the lateral magnification (3.1.90.8) of the primary image (3.1.75.2)

Note 1 to entry: The effect of a magnification changer is expressed as a tube factor, which may be varied step by step or continuously. In the case of an infinity-corrected objective, the same effect may be achieved by exchanging the tube lens for another of different focal length.

3.1.92

magnifier

converging lens (3.1.87) used between an object (3.1.104) and the eye to increase the viewing angle (3.1.147) and hence to provide a magnified image (3.1.75) on the retina of the eye

3.1.92.1

focusing magnifier

adjustable magnifier (3.1.92) used to help in the precise focusing (3.1.67) of an image (3.1.75) in photography and photomicrography (3.1.115)

3.1.93

marking of optical components

inscribing of data in the form of characters or colour bands onto optical components in order to indicate their optical properties, values of certain properties and the origin of a component

Note 1 to entry: Details are given in ISO 8578.

3.1.93.1

colour marking of objectives

marking (3.1.93) of objectives (3.1.106) by means of coloured rings and/or engraving to denote properties according to a colour code of objectives (3.1.93.1.1)

3.1.93.1.1

colour code of objectives

system of colour marking of objectives (3.1.93.1) by means of coloured bands applied to the mount of an objective (3.1.106) indicating a range of magnification (3.1.90) and other properties

Note 1 to entry: The colours may be assigned from black, through the spectrum from red to violet, and white to denote increasing magnification, as detailed in ISO 8578.

3.1.94

micrograph

record of an image (3.1.75) formed by a microscope (3.1.99)

3.1.95

micromanipulator

instrument which allows fine manipulation of components of a preparation by means of mechanical reduction of the movements of the hand whilst they are observed with a microscope (3.1.99)

3.1.96

micrometer

device for measuring small lengths

3.1.96.1

stage micrometer

special graticule (3.1.70) in the form of a scale carried at natural size on a microscope (3.1.99) slide (3.1.134) which is used as an absolute standard of length for calibrating microscope measuring systems

3.1.97

microphotography

photography, especially of documents, arranged to produce small images (3.1.75) which cannot be studied without magnification (3.1.90)

Note 1 to entry: Not to be confused with photomicrography.

3.1.98

microprojector

microscope (3.1.99) designed or adapted to project a magnified image (3.1.75) onto a screen (3.1.132) for demonstration or drawing

3.1.99

microscope

instrument designed to extend visual capability, i.e. to make visible minute detail that is not seen with the unaided eye

Note 1 to entry: The word is qualified by prefixes (electron, X-ray, acoustic, field-ion, etc.) unless it is clear from the context that the imaging involved is by means of light.

3.1.99.1

binocular microscope

compound microscope (3.1.99.3) in which a separate image (3.1.75) is presented to each of the observer's eyes simultaneously

Note 1 to entry: There are two types of binocular microscope: those in which, by the use of a special viewing tube and beam splitter, both eyes are presented with identical images, and stereomicroscopes.

3.1.99.2

comparison microscope

system of two microscopes (3.1.99) , optically linked to present their images (3.1.75) into one field (3.1.54)

Note 1 to entry: The image field is usually split so that the image from each microscope is seen in the corresponding half of the field enabling, for example, the fine details of two similar specimens to be compared.

3.1.99.3

compound microscope

microscope (3.1.99) in which the primary image (3.1.75.2) is generated by an objective (3.1.106) , or an objective and a tube lens (3.1.87.10) , and is observed through an eyepiece (3.1.52)

3.1.99.4

dissecting microscope

low-power microscope (3.1.99) of long free working distance (3.1.69) used for dissecting

Note 1 to entry: This is nowadays generally a stereomicroscope.

3.1.99.5

fluorescence microscope

microscope (3.1.99) in which the image (3.1.75) is formed by light (3.1.88) emitted by fluorescence (3.1.58) from the object (3.1.104) itself, and/or from a fluorochrome (3.1.60)

Note 1 to entry: The object may be regarded as self-luminous and the light emitted is not coherent.

3.1.99.6

infrared microscope

microscope (3.1.99) in which the image (3.1.75) is formed with infrared radiation (3.1.123.1) and is displayed by means of a photographic or electronic device

Note 1 to entry: Microscopy using near infrared radiation may be performed with a conventional microscope; microscopy in the far infrared requires special equipment.

3.1.99.7

inverted microscope

microscope (3.1.99) in which the object (3.1.104) is observed from beneath the stage (3.1.136)

3.1.99.8

light microscope

microscope (3.1.99) which uses light (3.1.88) as the illuminating agent

Note 1 to entry: This term is often loosely used to include ultraviolet microscopes and infrared microscopes.

3.1.99.9

monocular microscope

microscope (3.1.99) which presents the image (3.1.75) to only one eye

3.1.99.10

polarized-light microscope

microscope (3.1.99) specially designed or additionally equipped for polarized-light (3.1.88.1) microscopy

Note 1 to entry: In its fullest form it has a polarizer, analyser, strain-free lenses between the polars, a rotating stage equipped with a scale to measure rotation angles, a mechanism for centration of the stage and/or the objectives and a focusable eyepiece with centred and oriented cross lines. There is also a Bertrand lens and a tube slot for the insertion of retardation plates and compensators. A polarized-light microscope for reflected light is sometimes known as an “ore microscope”.

3.1.99.11

reflected-light microscope

microscope (3.1.99) which uses epi-illumination (3.1.73.2)

3.1.99.12

scanning optical microscope

microscope (3.1.99) specially designed to scan the object plane (3.1.117.5) or image plane (3.1.117.3) in a raster pattern

Note 1 to entry: Light signals at discrete and uniform intervals are received from the object by a photoelectric sensor and displayed on a screen or stored for further processing. The image is thus built up serially. There are two techniques of scanning: one is based on movement of the illuminating beam with the object remaining stationary, the other on the movement of the object, the beam remaining stationary. The instrument may be operated in the confocal imaging mode.

3.1.99.13

simple microscope

microscope (3.1.99) consisting of only one lens (3.1.87) , the objective (3.1.106)

3.1.99.14

stereomicroscope

binocular microscope (3.1.99.1) in which the object (3.1.104) is observed by each eye from a slightly different angle, such that disparate image (3.1.75) points will be imaged on corresponding points of the retina and thus cause stereoscopic perception

Note 1 to entry: The Greenough microscope has two completely separate optical systems inclined at a particular convergence angle with respect to each other with prisms and/or mirrors to give an erect image. More recent systems use a common main objective whereby the convergence angle of both paths of rays is achieved by dividing the pupil in the back focal plane of the objective.

3.1.99.14.1

Greenough microscope

original design of low-power stereomicroscope (3.1.99.14) due to Greenough, consisting of two separate compound microscope (3.1.99.3) systems mounted with their axes converging at an angle of between 10° and 15°, so that they observe a common object field (3.1.54.4) and in which prisms (3.1.119) and/or mirrors are fitted to erect the image (3.1.75) and usually to incline the viewing tubes (3.1.144.6)

3.1.99.15

ultraviolet microscope

microscope (3.1.99) in which the image (3.1.75) is formed with ultraviolet radiation (3.1.123.3) and is displayed and recorded by means of a photographic or electronic device

Note 1 to entry: The well-corrected conventional microscope with high transmittance in ultraviolet region may perform microscopy using the near ultraviolet; microscopy in the far ultraviolet requires special equipment.

3.1.100

microscope base

part of the microscope (3.1.99) stand which rests on the work table and to which the other parts of the instrument are attached

Note 1 to entry: In modern instruments, the base may contain parts of the illuminating system.

3.1.101

monochromat

lens (3.1.87) in which the change of focal length (3.1.61) with wavelength is uncorrected, and aberrations (3.1.4) are minimized for only one wavelength

Note 1 to entry: The term is usually used to describe an objective made of fused silica and designed to operate at a specific wavelength in the ultraviolet.

3.1.102

mounting medium

liquid, synthetic resin or other medium in which the object (3.1.104) or objects are placed for investigation with the microscope (3.1.99)

Note 1 to entry: For transmitted-light microscopy, this medium is transparent, colourless and of specified refractive index, enclosed between the slide and the cover glass. For reflected-light microscopy, the mounting medium is normally a resin with which the sample is impregnated so that a polished section may be made.

3.1.103

nosepiece

part of the body tube (3.1.144.2) which carries the objective (3.1.106)

3.1.103.1

centring nosepiece

nosepiece (3.1.103) equipped with a centring mechanism which allows the position of the objective (3.1.106) to be adjusted laterally until its optical axis (3.1.107) coincides with the rotation axis of a rotating stage (3.1.136.7)

3.1.103.2

revolving nosepiece

nosepiece (3.1.103) with a rotating turret which facilitates changing objectives (3.1.106)

3.1.104

object

anything from which an image (3.1.75) is formed

3.1.104.1

object marker

accessory which may be fitted to the nosepiece (3.1.103) which, when moved to replace the objective (3.1.106) , will mark an area of interest on an object (3.1.104) or preparation

3.1.105

object space

space on that side of an optical system where the object (3.1.104) is located

Note 1 to entry: In reflection or formation of a virtual image, this space may coincide with the image space.

3.1.106

objective

first part of the imaging system, consisting of a lens (3.1.87) , its mount and any associated parts, which forms a primary image (3.1.75.2) of the object (3.1.104) , either alone or in conjunction with a tube lens (3.1.87.10)

3.1.106.1

dry objective

objective (3.1.106) where the medium between the front lens (3.1.87) and the cover glass (3.1.34) , or an uncovered object (3.1.104) , is air

3.1.106.2

finite primary image distance objective

objective (3.1.106) corrected for a finite object to primary image distance (3.1.80.2.2) and which alone is capable of forming the primary image (3.1.75.2)

3.1.106.3

infinity-corrected objective

objective (3.1.106) corrected for an infinite object to primary image distance (3.1.80.2.2) and which, therefore is used with a tube lens (3.1.87.10)

Note 1 to entry: When combined with its normal tube lens of appropriate focal length, such an objective obtains its nominal magnification.

3.1.106.4

long-working-distance objective

objective (3.1.106) designed to have a longer free working distance (3.1.69) than a conventional objective of the same magnification (3.1.90)

3.1.106.5

plan objective

flat-field objective

objective (3.1.106) so corrected that the flattening of the curvature of the image field (3.1.4.4) in the primary image plane (3.1.117.4) is emphasized in addition to the correction (3.1.33) of other aberrations (3.1.4)

Note 1 to entry: This term does not imply any degree of correction for other aberrations.

3.1.106.6

spring-loaded objective

objective (3.1.106) so constructed that the front lens (3.1.87) and its mount will retract against a spring when brought into contact with the object (3.1.104) or an obstruction, thus preventing damage to either object or objective

3.1.106.7

screw thread for objective

screw thread for connecting a microscope (3.1.99) objective (3.1.106) to the nosepiece (3.1.103)

Note 1 to entry: Dimensions are given in ISO 9345.

3.1.106.7.1

RMS thread

screw thread for objective (3.1.106.7) , originally standardized by the Royal Microscopical Society

3.1.106.8

objective spectral transmittance by design

OSTD

Note 1 to entry: For more information on spectral transmittance see ISO 19012-3.

3.1.107

optical axis

imaginary line joining the centres of curvature of lens (3.1.87) surfaces of an optical system or sub-system

3.1.108

optical path length

optical distance

product of the geometrical length of an optical path in a homogeneous medium and the refractive index (3.1.125) of the medium containing that path

Note 1 to entry: The optical path length is expressed either in length units or as a fraction or multiple of a given wavelength. When the medium is inhomogeneous it is the sum or integral of the product of the geometrical lengths and refractive indices of the parts.

3.1.108.1

optical path length difference

OPD

difference in optical path length (3.1.108) between two optical paths due to differences in geometrical length, refractive index (3.1.125) , or both. The OPD is expressed in length units or wavelengths

3.1.109

parfocal

having the state that once any lens (3.1.87) of a set which can be an objective (3.1.106) , a tube lens (3.1.87.10) or an eyepiece (3.1.52) , has been focused on to the object (3.1.104) or adjusted so that the image (3.1.75) lies at its correct level, if this lens is exchanged for any others in that set at a constant setting of the microscope (3.1.99) , only minimal readjustment of focus (3.1.65) may be necessary to restore sharpness

Note 1 to entry: A small readjustment may be needed, however, because of the accommodation which may take place in the eyes of an observer. Tolerances for parfocality are given in ISO 9345.

3.1.110

phase

relative position in a cyclical or wave motion which is expressed as an angle, one cycle corresponding to 2π radians or 360°

Note 1 to entry: The term “in phase” corresponds to phase angles between the two occurrences of 0 and 2π radians (360°) or a whole number multiple of these.

3.1.110.1

phase difference

phase (3.1.110) angle or fraction or number of wavelengths by which one periodic disturbance or wave lags behind or precedes another in time or space

3.1.111

phase object

object (3.1.104) which produces a phase difference (3.1.110.1) between the direct light (3.1.45) and the diffracted light (3.1.40) , but has a small or negligible effect on the amplitude

3.1.112

phase plate

optical device used in phase contrast (3.1.32.4) microscopy which influences differently the phase (3.1.110) and amplitude of the direct light (3.1.45) and diffracted light (3.1.40)

Note 1 to entry: The phase plate is placed in the back focal plane of the objective (or in the plane of a succeeding image of it), where it receives an image of a diaphragm (usually annular) positioned in the front focal plane of the condenser.

3.1.113

photomacrography

production of a photographic image (3.1.75) of an object (3.1.104) with a reproduction ratio in the image between 1:1 to about 15:1

3.1.114

photomicrograph

photographic record of an image (3.1.75) formed by a microscope (3.1.99)

3.1.115

photomicrography

recording by photography of an image (3.1.75) formed by a microscope (3.1.99) ; i.e. photography through a microscope

Note 1 to entry: Not to be confused with microphotography.

3.1.116

pixel

smallest element of the digital image (3.2.13) to which attributes are assigned

3.1.116.1

pixel size

shortest distance from the centre of one pixel (3.1.116) to the centre of an adjacent pixel measured in object space (3.1.105)

3.1.117

plane

imaginary surface normal to the optical axis (3.1.107)

3.1.117.1

aperture plane

pupil plane

plane (3.1.117) containing the pupil (3.1.122) of an optical system and any plane conjugate (3.1.29) with it

Note 1 to entry: A diaphragm inserted in an aperture plane will act as an aperture diaphragm.

3.1.117.2

field plane

object plane (3.1.117.5) and any plane conjugate (3.1.29) with it

Note 1 to entry: A diaphragm inserted in a field plane will act as a field diaphragm.

3.1.117.3

image plane

any field plane (3.1.117.2) in which an image (3.1.75) is situated

3.1.117.4

primary image plane

image plane (3.1.117.3) in which the primary image (3.1.75.2) is formed

Note 1 to entry: The primary image plane is important as one of the reference planes for the optical interfacing dimensions.

3.1.117.5

object plane

that field plane (3.1.117.2) in which the object (3.1.104) is situated

Note 1 to entry: The object plane is important as one of the reference planes for the optical interfacing dimensions.

3.1.117.6

reference plane

surface of a microscope (3.1.99) component or a plane (3.1.117) in the light (3.1.88) path of the microscope, used as a limit for one of the optical interfacing dimensions (3.1.80.2)

3.1.118

polar

device which selects plane-polarized light (3.1.88.1.2) from natural light (3.1.88)

3.1.118.1

analyser

polar (3.1.118) used after the object (3.1.104) to determine optical effects produced by the object on the light (3.1.88) , polarized or otherwise, with which it is illuminated

Note 1 to entry: It is usually positioned between the objective and the primary image plane.

3.1.118.2

crossed polars

state in which the polarization directions of the polars (3.1.118) ( polarizer (3.1.118.4) and analyser (3.1.118.1) ) are mutually perpendicular

3.1.118.3

parallel polars

state in which the polarization directions of the polars (3.1.118) [ polarizer (3.1.118.4) and analyser (3.1.118.1) ] are parallel

3.1.118.4

polarizer

polar (3.1.118) placed in the light (3.1.88) path before the object (3.1.104)

3.1.119

prism

block of transparent material limited by at least two intersecting planes, used to disperse light (3.1.88) or deviate it through an angle

3.1.119.1

Nicol prism

type of polarizing prism (3.1.119.3)

3.1.119.2

Nomarski prism

form of Wollaston prism (3.1.119.4) , introduced by Nomarski, in which the crystal axis of one of the wedges is tilted

Note 1 to entry: The Nomarski prism has the effect of shifting the point of intersection of the two beams so that it lies outside the prism. In effect this enables recombination of the beams to occur at the back focal plane of the objective, while the prism itself lies beyond this plane. Prisms of similar design may also be used in the condenser.

3.1.119.3

polarizing prism

double prism (3.1.119) formed from two pieces of double-refracting material, which acts by refraction and total internal reflection or by refraction only

Note 1 to entry: The polarizing prism splits a beam of natural light into two beams of plane-polarized light having mutually perpendicular vibration directions and being propagated in two different directions. When one of these beams is removed, e.g. by absorption, the prism acts as a polar, otherwise it may be used as a beam-splitter. Many types of polarizing prism exist, most known by the name of their originator, e.g. Glan-Thompson, Nicol.

3.1.119.4

Wollaston prism

double prism (3.1.119) formed from two pieces of double-refracting material, which can be calcite or quartz, which acts by refraction and splits one beam of plane-polarized light (3.1.88.1.2) into two beams of plane-polarized light having mutually perpendicular vibration directions, propagated in two different directions

3.1.120

projection factor

p

factor by which the total magnification of a microscope (3.1.90.2) is changed when forming a real image (3.1.75.3) of the object (3.1.104) onto a detecting device such as a photographic emulsion in a camera

3.1.121

projection lens

lens (3.1.87) which forms a real image (3.1.75.3) , at a finite distance, of the microscope’s (3.1.99) primary image (3.1.75.2) and which is used for projection, drawing, photomicrography (3.1.115) and video purposes

3.1.122

pupil

minimum common cross-section of all ray bundles both in object space (3.1.105) (the entrance pupil) and in image space (3.1.76) (the exit pupil) of a lens (3.1.87)

Note 1 to entry: This term may indicate an aperture or the image of an aperture.

3.1.122.1

entrance pupil of the microscope

image (3.1.75) of the objective’s (3.1.106) aperture diaphragm (3.1.38.1) at infinity (except in the case of certain low-magnification objectives) in object space (3.1.105)

Note 1 to entry: If the microscope has an illuminating system, any plane conjugate with the microscope entrance pupil can also be called the entrance pupil of the entire microscope.

3.1.122.2

exit pupil of the microscope

eyepoint

area lying in a plane (3.1.117) several millimetres after the eyepiece (3.1.52) on the observer's side where an image (3.1.75) of the objective’s (3.1.106) exit pupil (3.1.122) is formed by the eyepiece together with any intermediate lenses (3.1.87.7)

Note 1 to entry: The exit pupil of the microscope is important because its position and size dictate the position of the pupil of the observer's eye and the nature of other succeeding optical systems such as cameras.

3.1.123

radiation

energy in the form of electromagnetic waves or particles

3.1.123.1

infrared radiation

radiation (3.1.123) in which the wavelengths of its components are longer than those for visible light (3.1.88) and less than about 1 mm

3.1.123.2

monochromatic radiation

radiation (3.1.123) consisting of only a single wavelength, or of only a very narrow band of wavelengths of which the central wavelength is quoted

3.1.123.3

ultraviolet radiation

radiation (3.1.123) in which the wavelengths of its components are shorter than those of visible light (3.1.88) and longer than about 100 nm

3.1.124

reference viewing distance

internationally agreed standardized distance of 250 mm between an object (3.1.104) and the vertex of the cornea of the eye

Note 1 to entry: This term supersedes the older “nearest distance of distinct vision” in optical calculations.

3.1.125

refractive index

norn '

ratio of the speed of light (3.1.88) (more exactly, the phase velocity) in a vacuum to that in a given medium

3.1.126

relief

<surface> differences in height of a surface, e.g. of a flat sculpture

Note 1 to entry: When illuminated from one side, such an object shows a characteristic distribution of light and shadow which enables the observer to recognize the three-dimensional form of the object.

3.1.127

relief

<contrast techniques> light (3.1.88) distribution appearing in microscopy using azimuthal methods like oblique illumination (3.1.73.4) , relief contrast (3.1.32.5) , differential interference contrast (3.1.32.2.1) or modulation contrast (3.1.32.3) at the interfaces of object (3.1.104) elements with different optical path length (3.1.108) , even when no geometrical relief (3.1.126) exists

Note 1 to entry: In this case, the light distribution appears similar to that produced by a genuine relief. Take care to avoid misinterpreting optical path length differences as being geometrical ones. A further misinterpretation of relief may be caused by inversion.

3.1.128

resolution

result of displaying fine details in an image (3.1.75)

Note 1 to entry: The term “resolution” sometimes refers to its quantitative expression, the resolved distance.

Note 2 to entry: When used without any qualification, this term refers to distances at right angles to the optical axis.

3.1.128.1

lateral resolution

resolution (3.1.128) perpendicular to the optical axis (3.1.107)

3.1.128.2

minimum resolvable distance

smallest separation of points in an object (3.1.104) which can be recognized as distinct in an image (3.1.75)

Note 1 to entry: In microscopy this is normally expressed in units of length (µm or nm).

3.1.128.3

resolved distance

distance equal to or greater than the minimum resolvable distance (3.1.128.2)

3.1.128.4

resolving power

ability to make points or lines which are closely adjacent in an object (3.1.104) distinguishable in an image (3.1.75)

Note 1 to entry: High resolving power implies that the resolved distance is small.

3.1.128.5

axial resolution

resolution (3.1.128) in the direction of the optical axis (3.1.107)

3.1.128.4.1

diffraction limit of resolving power

diffraction limit

fundamental limitation imposed upon the resolving power (3.1.128.4) of a system by the phenomenon of diffraction (3.1.41) alone and not by aberrations (3.1.4)

3.1.129

retardation

difference in optical path length (3.1.108) expressed in wavelengths, length units or phase angles between two mutually perpendicular plane-polarized light (3.1.88.1.2) waves

3.1.130

retardation plate

compensator

piece, or pieces, of optically anisotropic (3.1.8) material with plane faces, inserted between crossed polars (3.1.118.2) in a diagonal position to produce a specific optical path length difference (3.1.108.1) between mutually perpendicular plane-polarized light (3.1.88.1.2) waves

3.1.131

scale bar

line of calculated length drawn on a micrograph (3.1.94) to indicate the length in the micrograph of a stated length in the object (3.1.104)

3.1.132

screen

reflecting or translucent surface on which a real image (3.1.75.3) may be formed and observed

3.1.133

semi-apochromat

fluorite objective

objective (3.1.106) intermediate in its correction (3.1.33) and complexity of construction between achromats (3.1.6) and apochromats (3.1.13)

3.1.134

slide

flat rectangular plate of glass on which an object (3.1.104) is mounted for microscopical examination

Note 1 to entry: For calculation and correction of the condenser, it is regarded as part of the condenser, so that its thickness, refractive index and dispersion must be adapted to the demands of the condenser. These parameters together with its length and width are defined by ISO 8037-1.

3.1.135

source

source of radiation (3.1.123)

3.1.135.1

point source

source whose dimensions are sufficiently small to cause the emitted radiation (3.1.123) to have a very high degree of coherence

3.1.136

stage

microscope stage

platform, at right angles to the optical axis (3.1.107) of the microscope (3.1.99) , which carries the object (3.1.104) and which is often fitted with mechanical movements [as in a mechanical stage (3.1.136.6) ] to allow easy positioning of the object in the x- and y-axes, and movement along, and rotation about, the z-axis

3.1.136.1

centring stage

rotating stage (3.1.136.7) fitted with provision for bringing its axis of rotation into coincidence with the optical axis (3.1.107) of the microscope (3.1.99)

3.1.136.2

cooling stage

stage (3.1.136) fitted with means for lowering the temperature of the object (3.1.104)

3.1.136.3

gliding stage

movable stage (3.1.136) consisting of two flat plates, the upper of which can be moved smoothly in all directions in the x-y plane over the lower one, which is fixed to the stand (3.1.138)

Note 1 to entry: The ease of movement is regulated by the viscosity of the layer of grease which is used to connect the two plates.

3.1.136.4

heating stage

stage (3.1.136) fitted with means for raising the temperature of the object (3.1.104)

3.1.136.5

levelling stage

stage (3.1.136) designed to hold a polished section so that its surface is normal to the optical axis (3.1.107) of the microscope (3.1.99)

3.1.136.6

mechanical stage

stage (3.1.136) fitted with screw or rack mechanisms to assist in precise translational movement of the object (3.1.104) in the x and y directions

Note 1 to entry: The stage may be manually or motor operated, attachable, or built into the microscope stand. In computer-controlled microscopes, motors are used to drive the stage.

3.1.136.7

rotating stage

stage (3.1.136) fitted with means for rotating the object (3.1.104) with respect to the optical axis (3.1.107) of the microscope (3.1.99) which may or may not be centrable and/or calibrated for measuring angles of rotation

3.1.136.8

scanning stage

mechanical stage (3.1.136.6) electronically or electrically controlled to move the object (3.1.104) in steps or continuously in a raster fashion

3.1.136.9

universal stage

device mounted on a rotating stage (3.1.136.7) and equipped with a gimbal mechanism for movement of the object (3.1.104) , which enables the effect of optical anisotropy to be investigated at any direction of illumination (3.1.73) or observation

Note 1 to entry: The movements comprise calibrated tilting and rotation around three or four axes (according to the type of stage) in addition to the usual movements of the microscope stage.

3.1.137

stage clip

flat spring used to hold a slide (3.1.134) in contact with the microscope (3.1.99) stage (3.1.136)

Note 1 to entry: The use of stage clips facilitates the precise movement of a slide with the fingers.

3.1.138

stand

microscope stand

chassis on which the mechanical and optical parts of the microscope (3.1.99) are carried

3.1.139

stop

diaphragm (3.1.38) , usually of fixed size

Note 1 to entry: This term is often used loosely.

3.1.140

strain-free

property of a lens (3.1.87) intended for use with the polarized-light microscope (3.1.99.10) , manufactured by careful selection and mounting of its component parts so that double refraction (3.1.48) due to strain is minimized

3.1.141

substage

assembly of mechanical and opto-mechanical parts attached to the stand (3.1.138) of a transmitted-light microscope (3.1.99) before the stage (3.1.136) , consisting of the condenser (3.1.28) with its carrier and, optionally, a filter (3.1.55) tray, a polarizer (3.1.118.4) with its carrier and/or auxiliary lenses (3.1.87) with their carriers

3.1.142

temporal resolution

smallest time interval between sequential digital (3.2.13) or electronic images (3.2.14) from which independent information can be obtained

3.1.143

test object

object (3.1.104) designed to assess the performance of a microscope (3.1.99) system, e.g. Abbe test plate (3.1.1) , diatom preparation

3.1.144

tube

part of the microscope (3.1.99) which connects the objective (3.1.106) and the eyepiece (3.1.52)

Note 1 to entry: In early microscopes, the tube was in the form of a hollow cylinder carrying at one end the objective-locating surface and at the other the eyepiece -locating surface. In microscopes of more recent design, the tube may be divided into two or more sections or housings, one or more being attached to the stand. The housings may not be cylindrical but shaped to offer the most convenient manipulation of the included opto-mechanical elements. In the case of a reflected-light microscope, that part of the epi-illuminator, which is situated between the nosepiece and the primary image plane, is considered to be part of the tube.

3.1.144.1

binocular tube

viewing tube (3.1.144.6) designed to accept two eyepiece (3.1.52) for binocular viewing

3.1.144.2

body tube

part of the tube (3.1.144) , fixed to or incorporated into the stand (3.1.138) , containing the nosepiece (3.1.103) on one side and carrying the intermediate tube (3.1.144.3) or viewing tube (3.1.144.6) on the other

Note 1 to entry: For certain purposes, the body tube may contain optical or opto-mechanical elements, e.g. intermediate lenses, beamsplitter, magnification changer, reflector or epi-illuminator, Bertrand lens, mechanisms for operating filters, retardation plates, etc. For work with infinity-corrected objectives, it may contain the tube lens.

3.1.144.3

intermediate tube

optional part of the tube (3.1.144) which is a housing, either integral with the stand (3.1.138) or exchangeable, forming part of the tube and containing some opto-mechanical elements

3.1.144.4

monocular tube

viewing tube (3.1.144.6) designed to accept only one eyepiece (3.1.52)

3.1.144.5

trinocular tube

viewing tube (3.1.144.6) designed to accept two eyepieces (3.1.52) for binocular viewing, together with a third eyepiece or other lens (3.1.87) to enable simultaneous and/or alternate viewing and other use of the image (3.1.75)

3.1.144.6

viewing tube

part of the tube (3.1.144) equipped to carry one or more eyepieces (3.1.52) , limited at one end by the eyepiece-locating surface (3.1.89.2) and at the other by the body tube (3.1.144.2) locating surface (3.1.89)

Note 1 to entry: For use with infinity-corrected objectives, it may contain the tube lens.

3.1.145

tube length

distance between mechanical and/or optical surfaces or planes (3.1.117) in the tube (3.1.144) of a microscope (3.1.99)

3.1.145.1

mechanical tube length

distance in air between the objective-locating surface of the nosepiece and the eyepiece-locating surface of the viewing tube

Note 1 to entry: It is the length of the tube in its simplest form without any intermediate lenses for objectives corrected for a finite primary image distance.

Note 2 to entry: It commonly has a value of 160 mm. See ISO 9345.

Note 3 to entry: For infinity-corrected objectives, the mechanical tube length is hypothetically considered to be infinite.

3.1.145.2

optical tube length

distance between the back focal plane (3.1.62.1) of the objective (3.1.106) and the primary image plane (3.1.117.4)

Note 1 to entry: This distance is not one of the optical interfacing dimensions of the microscope and is relevant only to tubes fitted with finite primary image distance objectives.

3.1.146

tube factor

q

factor by which the lateral magnification (3.1.90.8) at the primary image (3.1.75.2) is changed by an intermediate lens (3.1.87.7) or lens (3.1.87) system inserted between the objective (3.1.106) and the primary image

3.1.147

viewing angle

angle subtended by an object (3.1.104) or a field (3.1.54) at the eye

3.1.147.1

angle of view

<eyepiece> angle between two principal rays coming from opposite points on the margin of the visual field diaphragm (3.1.38.8) of the eyepiece (3.1.52) and passing through the centre of the exit pupil of the microscope (3.1.122.2)

Note 1 to entry: The extent of the retina covered by the image is governed by this angle.

3.1.148

zoom

property of an optical system signifying that its focal length (3.1.61) and magnification (3.1.90) can be changed continuously between limits by moving a single lens (3.1.87) or group of lenses without altering the positions of the object planes (3.1.117.5) or image planes (3.1.117.3)