Output window for small projector

[Dr Laser]

I found that using UV camera filter reflects back a lot of blue. Which is no good. Blue is the one you want to save as much as possible.

[weartronics]

Thanks to everybody for so many ideas! The camera UV filter is a good idea for getting AR coated glass.

Troy: Good to see you on here! Yes I was able to get the Ar tube started, I built it in to a beam projector and sold it. It was an interesting learning experience, no profit in it though! Thanks for the info about the silica window. I was considering it because it's a convenient size for my projector and I don't particularly care about 10% reflection. However, I can't justify laserwolfer price - I suppose that's my clue that I only need glass!

weartronics

[MechEng3]

BTW the Hoya Skylight filters that are on all 3 of my projectors have an almost unmeasurable loss and backreflection from 405nm through 670nm at any power level up to 1/2 watt{max power here at one wavelength}. I would suggest them for price and performance aspects alone. Not to mention they are easily replaced if damaged. They are tough and clean up with denatured alky. Try one for yourself. Or come to SELEM and you can measure and inspect all you want. I would be glad to open a unit up for inspection. They are bearing 11 A/R coatings each side. Sizes up to 120mm with a nice threaded ring mount.

[Meduza]

Another option is www.flashlightlens.com

They carry a range of lenses with dualsided AR coating and 98%+ light transmission in sizes up to 72mm, all for less than 8$/ea

[heroic]

I just made an output window cover for my portable RGB 250 mW unit out of Edmund Optics Opticast plastic. So far my results are favourable; looks like about 5-10% of light is getting reflected. The material was easy to cut and drill with a Dremel, and it doesn't seem to mind 250 mW being pushed through it at a single spot.