Where are glass scale linear encoders used?

The most common application for glass scale linear encoders is ultra-precision machining, especially grinding machines and lathes for optics.

Acu-Rite SENC 150 Encoder Assembly

How Renishaw optical encoders work

: Industrial & Scientific

Linear Scale,Slim Scale,Optical Sensor,Glass Scale 50mm~300mm /2''~12'' 5um,EIA-422 Output, for Lathe,Milling Machine,Bridgeport,Drill,Quill, High

Linear Encoder, Optical Linear Encoders

Optical Encoder Strip, Custom Solution

EveryMarket

Summing the DRO Z-signals – Tech-Skill

Linear encoders Differences [Optical Incremental Magnetic Absolute]

Linear encoder - Wikipedia