High Power LED Collimating optics for projector project.?
My projector currently has a high pressure fancy schmancy bulb and when it goes (after another few thousand hours hopefully) I want to replace it with a high power (~100 watt) LED. That's the easy part. I can interface with the projector and convince it there is a real bulb firing up - but I need the optics. Basically, it's a DLP projector so all the light has to be focussed on just under a 2x2cm square hole to hit the colour wheel. The LED in question is already over that size on the diode die alone.
There are parabolic reflectors available (I think my best option) but they still have a positive beam spread - I need a shrinking beam. It doesn't have to be perfectly collimated, but I bet that helps. The original lamp definitely has a converging beam but its hard to measure as you can't operate the lamp with the cover open (safely).
I'm thinking diode >> reflector (like flashlight) >> convex or fresnel lens.
I can't get better measurements at the moment for I'm not near the machine and its finnicky to take off the ceiling. Penny for your engineering thoughts?
What I need but have never seen commercially:
LED to use:
dimensions about 5x5.5cm
Reflector I have in mind:
(rather wide beam still)
So...what I need are lens options. Based on my estimations I'll have several cm (up to 10cm) to come up with a good focus distance.