Please Help Me Understand Lens Materials!

Hey everyone!

I have been learning a TON since I started looking for the perfect light. So far I have a better understanding of different bulb types, different battery types, and many other things.

One thing I still don't have a grasp on is lens material. I know glass is better than straight up plastic, but what about polycarbonate? What material is better for what applications?

What sparked my inquiry was I noticed on the Pelican website that some of their lights use "polycarbonate," and others use "AR Coated Glass." I have also heard that some magpies have regular plastic lenses. I know polycarbonate is a form of plastic, but my "shatter resistant" Oakley eyeglasses are made of polycarbonate, and I have never had so much as a scratch on them.

So what's the deal with different lens materials? Which manufacturer should I look to to get the best lens material in stock lights?

I assume it's like blade steel in the knife community, with a lot being chalked up to preference, but I want to make sure I spend my money wisely.

Thanks!

Just have a look at flashlightlens.com, they have some useful information about glass lenses and their new AR acrylic lenses.

Depends too on your application and the type of abuse the light is likely to suffer. For example, glass is more scratch or pitting resistant than plastic, but more likely to shatter than plastic. So are your lights more likely going to encounter drops and impacts, or sand/grit/chemicals? Determining your usage needs will help you decide on a lens material.

Another determining factor is heat. As an example many years ago I had an original G2 with the P60 lamp assembly. I carried it in a holster on my belt. I had my computer set up so that I could slouch in my chair while surfing the web. One day I felt some warmth on my hip. When I checked, things had arranged themselves so that the tail cap was pressed by the way I was sitting. By the time I noticed it, the plastic lens had bubbled. That is when I discovered flashlightlens.com, and ordered one of their AR glass lenses. I just so happened that the switch to the glass lens increased the output of the G2 by several percent due to less loss due to the lens material. With today's high power LEDs I could see the same thing happening. Unless you are anticipating a very rugged environment that would be hazardous to a glass lens, switching to or selecting for a class lens would be worth the effort.

PS: My example was so long ago that my G2 did not have a lock-out tail cap. That is the other thing I changed.

I m a firm believer in sapphire glass vs even glass and wouldn't have plastic unless it was specifically designed to be rugged. Exposure lights UK seem to use some sort of plastic but not regular plastic and it's REALLY GOOD. Other companies also use special plastic or acrylic type...
I did a video comparing Ultra clear glass at 1" diameter and 2.85mm thick and sapphire same diameter but 3.02mm thick on a laminate floor (nothing happened so deleted the video... and then hard tiled floor... guess which one broke to pieces.