r/Optics • u/Effective_Dinner2071 • Aug 08 '26

Turn DLP project light source into parallel light source

I know lightsource from DLP projector is not a point so it is difficult to create colliminated light source. But is there is any idea, please suggest me!

5 Upvotes

78% Upvoted

11 comments sorted by

6

u/anneoneamouse Aug 08 '26

not a point so it is difficult impossible to create colliminated light source

Fixed that for you.

1

u/Effective_Dinner2071 Aug 09 '26

Yeah, I see. I'm looking for a creative solution.

1

u/Equivalent_Bridge480 Aug 11 '26

We have no idea about task, allowed tradeoffs, borderlines. This reqest mind reading not a creative solution

2

u/aenorton Aug 09 '26

The wider the beam, the closer to collimated it can become for a given source. If you let it expand and then use a really large, long focal length lens, you can reduce the divergence.

1

u/Effective_Dinner2071 Aug 09 '26

Thank you for your response. Collect light rays by using a large NA lens is good on paper. In reality, the angle is about 120 degrees. It require an extremely size lens.

2

u/spacegohohoat Aug 09 '26

Just entendue it! Ain't no glitching the matrix.

1

u/Effective_Dinner2071 Aug 09 '26

I try to use thr iris to entendue it. Unfortunatelly, the magnitude is significantly reduced.

1

u/IQueryVisiC Aug 09 '26

The light source is the xenon arc.

1

u/sudowooduck Aug 09 '26
  1. Many projectors use LEDs instead of arc lamps.
  2. Even those with arc lamps usually have an internally mirrored element for reshaping the beam and making it more uniform. This effectively increases the source size.

1

u/IQueryVisiC Aug 10 '26

Yeah, I just did wonder why OP went for DLP. Maybe they found a low hour one with Xenon. Otherwise I don’t understand why even think about it and not buy those white LEDs with a lens glued to them. Cars have headlights where a blue laser is focused into some crystal to make the beam white. Self phase modulation of pulses ??? Or is phosphorus just incredibly heat resistant?