Bridgelux 2600lumen LED DLP Projector mod

[cjsnr]

Planning a refit of an old dlp projector with the following LED from Bridgelux

• ES RECT 2600LM COOL WHT ARRAY 5600K
• Series: ES Rectangular Array
• LED Colour: Cool White
• Luminous Intensity @ Test: 965cd
• Luminous Flux @ Test: 2600lm
• CCT: 5600K
• Forward Current @ Test: 700mA
• Forward Current If Max: 1A
• Forward Voltage @ Test: 37.4V
• Viewing Angle: 120°
• LED Mounting: Screw
• MSL: MSL 1 - Unlimited
• SVHC: No SVHC (19-Dec-2011)
• Colour Rendering Index: 70

Will attach to a 50mm cpu fan/heatsink module that I got for ~£6, and lens from ledil

The psu is a cc LED driver from Meanwell, 700mA, 35W rated

Any suggestions on build and design ideas welcome

[AnAppleSnail]

The psu is a cc LED driver from Meanwell, 700mA, 35W rated

Any suggestions on build and design ideas welcome

I assume you are refitting and old metal-halide based DLP. A 17.5mm diameter light source might make things interesting. I believe DLP projectors use the following things that make life difficult for LEDs:

1. Color Filters to produce color (You may have weaker reds and oranges)
2. I don't know what a large source does to the optical behavior of the projection device

[blasterman]

Color Filters to produce color (You may have weaker reds and oranges)

Then use a neutral flavor LED - Bridgelux makes those as well. Check the original bulb specs for CCT and it will get you close although the spectrums will be different.

I'm more concerned about the grid pattern of the Bridgelux Array causing artifacts.

[cjsnr]

thanks for the replies guys, not sure how it will look myself.

Once I get things built I'll run some tests. It might not be the most suitable LED of the range, but seemed the brightest ES!



Not sure if that fan/hs combo will hold up to the ~30W dissapation either. Time will tell.

[cjsnr]

just been checking the CCT for the pj. Quite confusing but I could be lucky and be able to adjust it by the pj settings. It had colour temp settings and had factory settings which I could play with.

I guess these are managed by the colour wheel. I could be totally wrong on this.

[idleprocess]

Don't most DLP projectors use Xenon Short-Arc bulbs, which are about as close to a point source as you're going to get in a decently bright light source? Suspect your existing optics are going to be a bit ineffectual with that kind of light output.

I'm trying to imagine how one could compensate for a weak light source in a DLP projector. Unlike LCD, one can't tweak the color sub-pixel values to adjust color balance, although I suppose there are methods involving duty cycle for a particular "pixel" whenever the color wheel is in position for a deficient (or excessive) color.

[Paul Baldwin]

Hi,
interested to see how you get on with this I've recently been playing around with my old lcd projector and a Cree xl-m @2.7A. I've been more successfull than with the previous mc-e, as backed up by idleprocesses point above.

[The_Driver]

Most DLP projectors from the last decade use high pressure mercury short-arc lamps (Philips UHP and Osram P-VIP). These have basically the highest possible intensity (cd/mm2) while still being somewhat efficient compard to say xenon short arcs. A 120w bulb (like ma_sha1 is using here in his spotlight) already produces around 7000 lumens. A 250w one >20000. A 120W P-VIP form Osram has a surface brightness of 200,000 cd/cm^2, which is >200x of the intensity you stated for the bridgelux led.

I can't really imagine how you could get a useful picture with soo much less lumens and intensity, but I don't want to demotivate you. This porject is very interesting .

[idleprocess]

Most DLP projectors from the last decade use high pressure mercury short-arc lamps (Philips UHP and Osram P-VIP). These have basically the highest possible intensity (cd/mm2) while still being somewhat efficient compard to say xenon short arcs. A 120w bulb (like ma_sha1 is using here in his spotlight) already produces around 7000 lumens. A 250w one >20000. A 120W P-VIP form Osram has a surface brightness of 200,000 cd/cm^2, which is >200x of the intensity you stated for the bridgelux led.

At least I was right on the "short-arc" bit ...

I can't really imagine how you could get a useful picture with soo much less lumens and intensity, but I don't want to demotivate you. This porject is very interesting .

Suspect a better avenue would be to do something like the semi-standard LumenLabs LCD projector, but with LED's rather than the MH bulb they typically recommend.

[cjsnr]

As I said, we'll see what we get after a few tests.

I have a few photos so far. These ones have the ledil spot reflector in position but not attached yet. Still waiting for PS/cc to arrive (out of stock at Farnell)

http://imageshack.us/photo/my-images/835/dsc00774y.jpg/
http://imageshack.us/photo/my-images...sc00775qv.jpg/

I have the med and wide ledil reflectors but the spot one seemed most suitable (24degs). They do many lens too. No power=no light yet


FYI The pj will be in near total darkness in my home cinema setup. I have another pj (with a working bulb) in there now.
This is really a 'can we do it' project.

[The_Driver]

Updates?

[cjsnr]

Ok, build went fine, I used a cpu heatsink/fan combo which seems to handle the LED heat ok.

http://profile.imageshack.us/user/cjsnr/

All went ok when I powered the pj on, from what I could see the test card looked ok, but soon as I connected video, the pj's red/orange light came on meaning a lamp error and shut down. Seems the 'no lamp' mb short didn't work after I put the mod in. Not sure why yet.

I've been too busy to mess with this project lately, after starting a new job.

If anyone can help re the 'no lamp' short on a Benq DLP PB6110 please post a reply. I've looked everywhere., cheers.