Custom lens/window materials?

[Buck91]

So, I've modified one of my bike headlamps with some upgraded emiters and I'm considering switching the optics for some reflectors (to tighten up the massive flood). I'm also considering replacing the window (which is 2/3 frosted) with a clear one, but that is where I get hung up.

Its not exactly a typical flashlight window (link to thread about this light), so I either have to find somebody to make one or make one that will work myself. I have not been able to find anybody to make me one, so that leaves the DIY option. But what type of material would I want to use? I would assume glass would be very hard to shape in that manner and would take a long time and a lot o abrasives. PC/lexan may work well, although it does age with time and yellows out. What about acrylic? I'm really at a loss for what the best option would be!

 

[Mick]

http://www.edmundoptics.com/onlinecatalog/displayproduct.cfm?productID=1916

 

[Buck91]

Oh cool! Have you used this before? Hows the transmicity (is that a word)?

 

[Mick]

Sorry I forgot to check back here. I have not used this material but found it when searching for a plastic window. From Edmund specs it is greater than 90% transmission. I'm sure that is in the visible range. That is better than most plastics but glass with a coating can go as high as 98%. Cast Thermoset ADC is certainly more brittle than lexan but way easier to work than glass. Edmund thinks everything they sell is made of gold.