The most common variety of LED illumination optics are freeform lenses, as well as TIR lenses, and light pipes. These are usually created with injection molding and use plastic. Glass materials are often used however this can be less common and used largely with sphere lenses or asphere for brief vary illumination tasks like optical instruments with abbe or Köhler illumination.
We at Siddharth Opticals drive our research to find the best materials possible and avail our service to buy optical online to our clients.
The ‘top 5’ listing below is predicated on our expertise of often used plastics. The ‘best’ material for a given application is very passionate about technology needs.
1. PMMA
The most widely used plastic material is polymethylmethacrylate, additionally referred to as PMMA, acrylic or plexiglass and Acrilite brand names. benefits of this material are low price, simple mold-ability into any form, high lightweight transmission, “green” material characteristics and high UV transmission. Drawbacks of this material are known like, if prolonged UV exposure is happened, it gets yellowish, higher water absorption, that it’s easily damaged and fewer heat resistant than different plastics.
Many a times, Varilux lenses can be found with such material.
2. Polycarbonate
Second place plastic material is polycarbonate, additionally referred to as pc or Macrolon and Lexan brand names. This material has a lot of scratches resistant than pmma, is harder, have a higher index of refraction, simple for molding, lower water absorption, and better-softening temperature than pmma (130 C). Disadvantages of pc are – yellowing below prolonged UV exposure, not as “green”, some toxicity and not appropriate for many biomedical applications, have high double refraction, higher value. Polycarbonate has terribly low UV transmission below 400 nm, therefore, is widely used for the sport outside safe-eye glasses.
3. Zeonex
Third place material is Zeonex materials specially designed by Zeon company. Zeonex is quite a Cycloolefin polymer. These materials are beneficial because of their properties like the high light transmission, terribly low yellowing below UV exposure, very low tide absorption considerably but pc and pmma, high thermal resistance, softening temperature are 130-150 C, “green” material appropriate for medical applications, low double refraction and high abbe range, smart chemical resistance. The main disadvantage is far higher value.
4. PMMI
Fourth place material is polymethacrylmethylimid referred to as pmmi or trademark is Pleximid. this can be quite pmma like plastic, however, it’s very high softening temperature regarding 170 C. it’s used for applications that involve most thermal masses. The key optical properties are almost like pmma.
5. Optical silicone resins
Fifth place is optical polymer resins. These are the latest kind of optical material that have some advantages over pc and pmma like higher temperature resistance up to 150 C, higher UV yellowing stability, low consistency cure which permit it to be simply shaped in smaller components like microarrays. except for currently, they are not widespread as pmma or pc.
