LED aperture - white light interferometry

[lightdelight]

I am wondering who has built a light with high spatial coherence? How close is it possible to mount an aperture to the phosphor? My method right now is a pinhole aperture on the bezel of a Z44 with an m30 inside. The aperture is quite far away. My figuring is the closer the better. Aperture directly on the phosphor would likely not be a good idea. Maybe a close shaving of the dome? There will be a lot of wasted light, and better results would come from an LED with high surface intensity. Any suggestions?

 

[Dr.Jones]

XP-C overdriven and well heat-sinked, shaved dome, pinhole on top, should give the best luminance.

 

[AnAppleSnail]

Put a reversed parabola on the LED with a pinhole. Phosphor restrike will conserve some of that light. ditto on XP-C choice.

 

[lightdelight]

Ah yes! Good call with the parabola. I suppose any reflector would work for me, but a smaller, steeper one might be best. Can I just epoxy that onto the mcpcb?

I was looking at some 5mm LEDs, and their die size may be small enough already. I tried to shave one..didn't work too well. Guess I need a better blade.

Thanks for the help!

 

[AnAppleSnail]

Ah yes! Good call with the parabola. I suppose any reflector would work for me, but a smaller, steeper one might be best. Can I just epoxy that onto the mcpcb?

I was looking at some 5mm LEDs, and their die size may be small enough already. I tried to shave one..didn't work too well. Guess I need a better blade.

Thanks for the help!

Try the 'straw hat' or otherwise flattish LEDs. These have less optical work done, making the LED more like a point source. Radio Shack sells 4-pin LEDs that should do well, having no optic above the LED phosphor.