IS 18909 : 2024/ISO 9802 : 2022 Raw Optical Glass - Vocabulary

ICS 01.040.81; 81.040.10

PGD 39

NATIONAL FOREWORD

This Indian Standard which is identical to ISO 9802 : 2022 'Raw Optical Glass - Vocabulary' issued by the International Organization for Standardization (ISO) was adopted by the Bureau of Indian Standards on the recommendation of the Optics and Photonics Sectional Committee and approval of the Production and General Engineering Division Council.

Raw optical glass comes as strip glass, pressings block glass or large castings. Its characteristics are widely the same as those for optical elements such as lenses and prisms. However, the tolerance limits and their applicability are not the same. Considering the importance of this subject, the Optics and Photonics Sectional Committee decided to adopt the ISO 9802 as an Indian Standard.

The text of ISO standard has been approved as suitable for publication as an Indian Standard without deviations. Certain conventions are however not identical to those used in Indian Standards. Attention is particularly drawn to the following:

a) Wherever the words 'International Standard' appear referring to this standard, they should be read as 'Indian Standard'; and

b) Comma (,) has been used as a decimal marker while in Indian Standards, the current-practice is to use a point (.) as the decimal marker.