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Projector mod conversion - UHP lamp to laser... RGB? - help!

Harcoreta

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Hi! I'm new in this amazing forum.

I'm working in a modification on a JVC RS46 projector, I've already done the ballast bypass for the UHP lamp and now trying to convert it to laser.
I'm designing the lightpath using two OSRAM PLPM4L 450B blue laser arrays rated on 80 output watts each. One of these for produce yellow color with a phosphor wheel, and the other for blue color only.
But i'm thinking if it's viable to use RGB laser light source instead blue laser only + phosphor wheel. The original UHP lamp power is 230W and the projector is rated at 1300 ANSI lumens.

My question is... How much red and green laser power I would need to try to achieve the same output luminance?

I'm not very familiar with Lumens/ANSI lumens/effective laser lumnes per watt... Any suggestions will be greatly appreciated :)
I hope with one 80w blue laser array only is plenty enough for blue color. But red and green lasers are not very cheap, if the cost is not too expensive I could try it.

For this mod project I have planned also to do dynamic lighting, like a dynamic iris but controlling the laser power. The code is also done. I bought a cheap programmable power supply (DPM8608), and with the ffms2.dll plugin that works with avisynth you can log to an archive the average luminance in the scene. I did a simple script in powershell to take that information and send the desired voltaje/current command to the power supply. I suppose the code can be improved, I'm not a programmer, but it works very well, I used only a computer with a usb serial ttl. Possible It will be the first cheap JVC projector (not dla-Z1) with ∞:1 contrast xD

Regards.
 
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hakzaw1

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ok
pretty sure the search here will not produce...
but someone will reply,, ya never know.

be carefull
scary amount of power..
'styropyro' has experience w/ lots of blue.


hak
 

Harcoreta

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Thanks!
yes,'styropyro' has done incredible experiments, I've seen a lot of his videos.

Looking for information about necsel lasers, luckily I found a good article about
"Laser-based displays"
(sorry I don't have rights for put links, but I have to put the source :))

https:// www. researchgate.net/publication/46158627_Laser-based_displays_A_review

There is an interesting table about "Laser Optical Power Ratio for 6500K" (6500K color temperature white point is the standard) :)

Representative Laser Wavelengths (in nm)
Red Green Blue Power Ratio (R:G:B)
633 532 465 1:0:73:0:64
635 532 465 1:0:68:0:60
640 532 442 1:0:66:0:46
650 532 442 1:0:42:0:29
670 532 442 1:0:13:0:09

Seems that the highest laser power would need to be red.
It's a good start point, I can do some test with my blue laser, measure it's luminance with a colorimeter, write down the power measurement, and then calculate the necessary power for the laser colors red and green.
 

Cyparagon

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Projector lumen ratings are based on light OUTPUT, not input. The conversion efficiency depends heavily on the optical train.

Since your model originally had a 230W lamp, I would expect ~13,000 lumens, so you lose 90% in the optics. That may or may not be less with a laser, but interfacing the color wheel with the DMD chip isn't going to be easy.

If you're doing it to waste time and money - that's fine - we all do those things for fun on occasion. But make no mistake, This whole endeavor is NOT practical. At all.
 

kecked

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I think you will be much more satisfied buying a new QLED tv with the same money. If for fun yea if for performance not so much.

also think about the heat. In a lamp it’s all IR. In this it’s that plus waste heatfrom heating the parts. You might melt lens and such.

here’s one just for fun. Can you use a lightpipe of some sort and drive it with the sun. Put an IR blocking filter on it.
 

Harcoreta

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Projector lumen ratings are based on light OUTPUT, not input. The conversion efficiency depends heavily on the optical train.

Since your model originally had a 230W lamp, I would expect ~13,000 lumens, so you lose 90% in the optics. That may or may not be less with a laser, but interfacing the color wheel with the DMD chip isn't going to be easy.

If you're doing it to waste time and money - that's fine - we all do those things for fun on occasion. But make no mistake, This whole endeavor is NOT practical. At all.

You are right!
it's going to be very difficult to don't waste to much light and put it in the correct path to match the panels. I have two blue laser arrays, and lot's of different lens, I would like to try the experiment, but it is very possible that I will not reach the goal.

About the luminance, "lumens" seems that it is not the same than "ANSI lumens". 13,000 for de UPH lamp is an interesting information ;), would be very interesting to know how much laser power would be necessary to reach that numbers.


I think you will be much more satisfied buying a new QLED tv with the same money. If for fun yea if for performance not so much.

also think about the heat. In a lamp it’s all IR. In this it’s that plus waste heatfrom heating the parts. You might melt lens and such.

here’s one just for fun. Can you use a lightpipe of some sort and drive it with the sun. Put an IR blocking filter on it.

The problem is that I want to fill a 145" screen :), there are no TV with those sizes now, if there are any probably prohibitively expensive, projector is the only way for now :)

Sure also can use the sun :), I think with very big lenses in the outsice, a monitoring system to track the sun and multiple or a very big optical fiber tu put the light into the projector, it could be done, but at night there are no party xD

Regards.
 

RedCowboy

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No not prohibitively expensive.

I bought a brand new projector for less than some are selling a single nubm array, it worked just fine before I harvested the laser diodes........point is you can buy a much better working projector for a lot less and have a much better image......Why re-create all this when you can buy one ready to use for not much money ?

1604713672200.png
 

Harcoreta

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yes! big TVs are prohibitively expensive, also laser high end home projectors.
There are cheap laser projectors, but all of them are DLP based (for me a DLP projector is the same as a rainbow generator xD, they are all discarded), and with very low image specs, resolution, contrast, etc...

3-LCD or LCOS are the options, but...

Epson LS10000 - $7,999
Sony VPL-VW790ES - $12,000
JVC DLA-Z1 > $20,000

I want to try it with the JVC RS46, not a very high end projector but with very good specs. In the rare case that the experiment works xD, I would do the same with a JVC X700R projector, that is my main projector installed in the 145" screen setup. Both projectors share the same housing, lamps circuit, lightpath... but the X700 has slightly better specs.
 
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