PGX Lens Performance with Heat Treat v. Chem Treat

[Aarlan]

Hello all,

Just a quick query for all of those who still remember PGX lenses. I have been doing this for 17 years, and my father has been making eyeglasses since dinosaurs roamed the earth. It has always been my understanding that chem tempering is safer, but the heat treating (that few labs still perform) results in a photochromic that performs better (darker and quicker).

I was just having a conversation with a lab owner, and he was claiming that the chem treated pgx perform better after 6 weeks or so. I have NEVER had a complaint about heat treated lenses in all the time I have been dispensing, yet whenever we switched to chem treat we were almost lynched.

Any input?

AA

[Framebender]

My Dad was a dinosaur too!! We still heat treat everything that we possibly can. We've found that not even the new high index photochromatics can hold a candle to a good old crown PGX that's been run through the heat treater. I will say that Thin & Dark is close though.

I hope you're all having fun and making money!!

Framebender

Proud to be living proof that nobody works as cheap as your own kids!!

:cheers:

[Aarlan]

So I'm assuming that you are agreeing that a heat treated PGX has better photochromic ability than a chem tempered PGX?



AA

[HarryChiling]

I worked in a lab where we did about 3-4 pair of glass lenses a month. Usually they were for the elderly. I heat treated lenses it is easier, If I remember correctly it was 15 seconds less than a clear glass lens and the photochromics were better or quicker to react. I melted more than my fair share of lenses and cooked my fingerprints into more than a few as well.

[Jacqui]

PGX is best heat treated. I learned this many, many, moons ago at AO, it still holds true. I have a pair that are at least 10 years old and work as good as the day I made them.