Do you know Glass Code

Publisher:webmaster   Release time:2018-04-09   Browsing volume:3145

A glass code is a method of classifying glasses for optical use, such as the manufacture of lenses and prisms. 

There are many different types of glass with different compositions and optical properties, and a glass code is used to distinguish between them.

The international glass code is based on U.S. military standard MIL-G-174, and is a six-digit number specifying the glass according to its refractive index "nd" and its Abbe number "Vd". 

For example, BK7 glass code is 517642
The first 3 number means its Refractive index=1.517 (
The last 3 number means its Abbe number=64.2 (xx.x)

The glass properties can vary slightly between different manufacturer types, the following table shows it.

Find more information at LPO Resources "Material data" page.