The polymer used for optical lenses is :
Show Hint
- polypropylene
- polyvinyl chloride
- polythene
- polymethyl methacrylate
The Correct Option is D
Solution and Explanation
Polymethyl methacrylate (PMMA, also called Perspex, Plexiglas or acrylic glass) is the transparent thermoplastic made from methyl methacrylate, \(\mathrm{CH_2{=}C(CH_3)COOCH_3}\), and is used for lenses, aircraft windows and light covers.
Polypropylene, PVC and polythene are translucent/opaque, not used for lenses.
Answer: (4) polymethyl methacrylate
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