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A comment on Measuring Your Own Pupillary Distance. Parent comment

Re:Measuring Your Own Pupillary Distance by CalChris on Saturday September 02, 2017 @06:12PM (#15158497)
Yeah, I got that backwards. Point is that CR39 is not exactly better optically. Trivex is significantly better chromatically than PC, 1.60, ... In addition, Trivex acts as a UV cutoff filter.

What I couldn't figure out is whether a CR39 lens' comparative thickness (prism length) vs a thinner Trivex lens degrades its chromatic aberration advantage in practice.

http://eclecticeyewearaustin.com/wp-content/uploads/2016/05/...

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Re:Measuring Your Own Pupillary Distance by boptom on Monday September 04, 2017 @09:08PM (#15171842)
Generally, you would expect lenses with a higher refractive index to be thinner.

However, due to the selling point of Trivex being "shatter proof" it has a greater centre thickness (to pass safety lens regulations), and thus the edge thickness is also comparable to CR-39.

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