any of several types of clear homogeneous glass of known refractive index used in the construction of lenses, etc
optical flint, optical crown
optical glass in American English
noun
Optics
any of several types of high-quality, homogeneous, color-free glass, as flint or crown glass, having specified refractive properties, used in lenses and other components of optical systems
Word origin
[1740–50]This word is first recorded in the period 1740–50. Other words that entered Englishat around the same time include: caricature, damper, etiquette, outrigger, snappy
Examples of 'optical glass' in a sentence
optical glass
It's not the optical glass that fascinates me.
Times, Sunday Times (2010)
Sunglasses, especially worn indoors, have been a fashion constant for years but this fake optical-glasses thing ebbs and flows in and out of style.