ISO 20793:2024 写真 | ページ 2

3.1 用語

Foreword

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This document was prepared by Technical Committee ISO/TC 42, Photography.

This first edition of ISO 20793 cancels and replaces the first edition of ISO/TS 20793:2019, which has been technically revised.

Introduction

Lenticular printing is a technology wherein lenticular lenses are used to produce printed images with an illusion of depth, i.e. three-dimensional (3D) effect, or the ability to change or move as the image is viewed from different angles. Lenticular prints for displaying changing images are built up with a lenticular lens sheet and a printed sheet that contains at least two images, interleaved with the same spatial frequency as the lenticular lens sheet.

In this context, lenticular lenses generally take the form of arrays of cylindrical lenses, each acting as a magnifying lens. Widespread applications of lenticular printing are signage, display posters, business cards, multilingual message boards, packages with changing images or 3D effects, and secure documents.

It has been reported that the market size of lenticular prints is over 100 million m² and that the market is growing. Furthermore, the potential image qualities of lenticular printing have dramatically improved, and further improvements are expected in the future. While production of lenticular sheets with a lens frequency of 100 lpi (lines per inch) is routine, products with a 200 lpi frequency are also currently available.

Although the potential image quality of lenticular prints is high as described above, the quality of images is not always good in the market due to various causes, e.g., due to the misalignment of the lenticular lens and lenticular printed images. This is a critical problem for lenticular printing.

To improve the image quality of lenticular prints, image quality measurements are essential. This document provides standard measurement methods and the specifications for the image quality of lenticular prints.

1 Scope

This document specifies the measurement methods and specification of image quality of lenticular prints that are used for changing images. This document does not cover lenticular prints that are used for 3D images.

This document specifically describes measurement methods for crosstalk, viewing angle range, angular misalignment from the designed viewing angle and the uniformity of the image within the printing area of the lenticular print images. These are critical for the image quality of lenticular prints for changing images.

This document is applicable to lenticular prints produced by printing technologies that include impact and non-impact printing. Examples of the former are off-set, gravure and flexography, while the examples of the latter are silver halide, inkjet, dye diffusion thermal transfer and electrophotography. The multiple laser images (MLI) and changeable laser images (CLI) process of using a laser to write through a lenticular screen at different angles to create two monochrome images is also used.

2 Normative references

The following documents are referred to in the text in such a way that some or all of their content constitutes requirements of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.

3 Terms and definitions

For the purposes of this document, the following terms and definitions apply.

ISO and IEC maintain terminology databases for use in standardization at the following addresses:

3.2 Abbreviations

Bibliography