Guys, buy two of the 170 mW single mode 638 reds, combine them with a pol cube and save your money. You will be MUCH happier with what you get.
I had my hands on the big ones a while ago. They are awe inspiring red sources for video projectors, or a short throw lumia in a planetarium.
Burning stuff: NO.
If you could get them internally microlensed they might be useful.
(Forget it, I had a talk with the leading microlens company, and nothing less then doing 2K pieces would interest them)
Even with microlensing, the projected losses were high. There is a issue that limits... That I cannot get into.
35' in my opinion is, well, optimistic.
I'd love to show you a test shot at 70' feet, but I signed a NDA for that work. I had it mounted on a handheld optical system.
Losses before the second optic approached 50% at best collimation at 70 feet, and that spot was huge, measured with a tape measure on one axis, not a ruler.
I had serious money behind me on the optics.
A single lens will not collimate these diodes to a pointerlike state without very large losses. I tried a lot of tricks, prisms, Drlava's lens set, going into fiber etc.
OK, I just pushed the limits of my NDA to tell you that. Please don't ask, I can't tell you more.
One of the funny things is even if you guys got your hands on samples, I could still not tell you what I know, the NDA is a restrictive one.
SAVE YOUR MONEY!
Steve
