CR-39 need coatings?

[douglasrac]

Hi,

CR-39 lenses are scratch resistant, at least compared to high-index lenses or even poly carbonate.
Due to high abbe number, I think CR-39 is the best to recommend for people that don't want to use glass lenses but are also unsatisfied with high-index lenses, due to less visual comfort.

My question is: when choosing CR-39 lenses, is it necessary to apply anti-reflex, anti-scratch coating?

[Chris Ryser]

My question is: when choosing CR-39 lenses, is it necessary to apply anti-reflex, anti-scratch coating?

No...............it is not necessary. But these additional coatings de provide some benefits for the consumer and as well to the optical provider as it is an additional sale.

Anti-scratch or scratch resistant coatings coatings can be bought ready on finished stock lenses or your lab can appply them. The self application in house is of course the most profitable and can be done on a machine as well a through simple dipping.

AR coatings do need some expensive machinery to do the application as well as some seasoned technicians to do a good job.

[opticallens]

It was said CR-39 uncoated lens is much better than coated ones.
But buyers have different requirement on coating. As a supplier of lenses we should have uncoated and coated ones so the customers can choose.

[Chris Ryser]

Uncoated CR 39 can be coated many different ways in your own backroom lab. You can treat them for scratch resistancy, UV. tint, anti fog, hydrophobic for lttle money yourself with very little equipment.