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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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HDMaster

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Hi Harcoreta,

i am just working on a project similar to yours.
I have a Sony VPL-VW260 4K Projector with 1500 ANSI Lumens.
My screen is a 158". 1500 Lumens is not enough for HDR with this size.

In the next two weeks i will get a laser engine from EPSON which will fit to my projector.
I can choose between 5000 to 8000 ANSI Lumens. The engine is originally for an EPSON LCD projector.
There are 4 different versions of it.

At first i will use the blue/yellow version with an dci filter.
So i can correct the colors.

I understand, why you are trying to pimp the older projector.
It is the same reason in my case.
The new projectors will be more expensive as doing the hack.

Good luck for your project
 

farbe2

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Interesting stuff, i am in. My VW270 also needs an upgrade.
However for red we only have these 17W 638nm arrays.
These are also quite expensive. As we would need way more red, i would go with multiple 700mW MM Ushio sharp diodes. These are quite cheap (around 15$/pc). So making a array of say 30W would need 42 diodes.
I would go with 49 diodes as it would make a 7x7 array. However a uneven array might be better as these diodes are quite less divergent in one axis. So maybe a 10x5 array would be good. However red alone would therefor be around 750$, a little to much for me.
Green would be expensive too.

So seems like thats why every laser projector i know uses phosphor converted blue for all other colors. Does anybody know a projector that uses red/green arrays?
I tried to get one of these converter phosphor plates but had no luck.
Schott does have these but they would not sell me one/two. Efficiency is also outstanding on these converters.
 
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Sowee7

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Interesting stuff, i am in. My VW270 also needs an upgrade.
However for red we only have these 17W 638nm arrays.
These are also quite expensive. As we would need way more red, i would go with multiple 700mW MM Ushio sharp diodes. These are quite cheap (around 15$/pc). So making a array of say 30W would need 42 diodes.
I would go with 49 diodes as it would make a 7x7 array. However a uneven array might be better as these diodes are quite less divergent in one axis. So maybe a 10x5 array would be good. However red alone would therefor be around 750$, a little to much for me.
Green would be expensive too.

So seems like thats why every laser projector i know uses phosphor converted blue for all other colors. Does anybody know a projector that uses red/green arrays?
I tried to get one of these converter phosphor plates but had no luck.
Schott does have these but they would not sell me one/two. Efficiency is also outstanding on these converters.
the only projectors ive seen that use other colors other than blue arrays are laser pico projectors, most contain red, green and blue but some can contain cyan and orange-red to
 

farbe2

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What wavelength is the "orange-red" laser you talk about?
Also: where did you get your 627nm 0,8mW laser module from?
 

Harcoreta

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Hi Harcoreta,

i am just working on a project similar to yours.
I have a Sony VPL-VW260 4K Projector with 1500 ANSI Lumens.
My screen is a 158". 1500 Lumens is not enough for HDR with this size.

In the next two weeks i will get a laser engine from EPSON which will fit to my projector.
I can choose between 5000 to 8000 ANSI Lumens. The engine is originally for an EPSON LCD projector.
There are 4 different versions of it.

At first i will use the blue/yellow version with an dci filter.
So i can correct the colors.

I understand, why you are trying to pimp the older projector.
It is the same reason in my case.
The new projectors will be more expensive as doing the hack.

Good luck for your project
Wow! seems very interesting :) I hope you have enough space to fit the laser engine. Can you post the model of these EPSON laser engines? I am very curious ;)
If you want to fill a 158" screen you need a lot of light. I am being much more conservative, my goal is to put 12 foot lamberts in a 145", an only for watch SDR. I've achieved this goal but not was easy xD
Please post your advances ;)

Interesting stuff, i am in. My VW270 also needs an upgrade.
However for red we only have these 17W 638nm arrays.
These are also quite expensive. As we would need way more red, i would go with multiple 700mW MM Ushio sharp diodes. These are quite cheap (around 15$/pc). So making a array of say 30W would need 42 diodes.
I would go with 49 diodes as it would make a 7x7 array. However a uneven array might be better as these diodes are quite less divergent in one axis. So maybe a 10x5 array would be good. However red alone would therefor be around 750$, a little to much for me.
Green would be expensive too.

So seems like thats why every laser projector i know uses phosphor converted blue for all other colors. Does anybody know a projector that uses red/green arrays?
I tried to get one of these converter phosphor plates but had no luck.
Schott does have these but they would not sell me one/two. Efficiency is also outstanding on these converters.
Yes, Red ang green lasers are very expensive! Finally I'm using a phosphor wheel, but it's hand made xD. I bought yellow phosphors with different wavelengths, mix it with silicone and put it in a HDD plate. Surely It is less efficient than a manufactured phosphor wheel, but it produces the perfect color temperature for use all the working range of the projector panels, I can basically use the High bright mode in the proyector being D65 calibrated, geting better contrast comparing with the original lamp.

Phosphor wheel 2.jpg

The project is very advanced, I've reached the primary goal, I can put the same light output comparing with the lamp. Also tested the dinamic lightning and works very well, now can turn off the laser on black frames :). And the native contrast was increased from 29000:1 to 48000:1 :O.
But I have some issues related to the blue color, it's undersaturated in the color gamut triangle. I'm using a Osram PLPM4L 450B laser array, it's rated at 450nm, but I'm measuring 400 or 410 nm, I am having the same result measuring with 2 colorimeters (Syder 4 and i1Display pro) and one spectrophotometer (xrite colormunki photo). Also I took apart the laser and measured directly with the colorimeter, and got the same undersaturated blue reading.
I've a nichia NUBM38 blue array on the way, it's rated at 455nm, hopping I could improve the blue color. I'm using a NUBM36 with the phosphor wheel, I can't measure it because I don't want to disassembly too much xD, it's a headache to adjust the pieces again, but with a naked eye the nichia is more bluish than the osram, the osram tends a little to more purplish color.

Laser Color gamut 2.jpg

I'm working in the external power supply now, hope to complete the project in about two or three months.

Here you have some photos taken past a few days ;)
Intake 2.jpg
Exaust 2.jpg
Duct preview 2.jpg
Lens ans Wheels 2.jpg
perspective 2.jpg
Top view 2.jpg
Working 2.jpg
Installation 2.jpg
 

HDMaster

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Respect! for your progress.
About your blue issue, i am not quiet shure if this is a problem with the narrow banded laser light.
Our sensors have problems with measuring laser sourced projectors.

How many lumens do you have with your engine ?

"Enough space": My plan is to get more space by building a bigger case for my projector.
The VPL-VW760/790 is much bigger as my VPL-VW260.

Good luck for your project
 

Harcoreta

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Messages
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Respect! for your progress.
About your blue issue, i am not quiet shure if this is a problem with the narrow banded laser light.
Our sensors have problems with measuring laser sourced projectors.

How many lumens do you have with your engine ?

"Enough space": My plan is to get more space by building a bigger case for my projector.
The VPL-VW760/790 is much bigger as my VPL-VW260.

Good luck for your project
Thanks HDMaster ;)
Wow! it doesn't seem like an easy jod to move all components to other housing.
I ended up removing the original lamp ducting and redesigning completely. Also to save space I'm using a water cooling with an external radiator for the nichia array.

I'm sure the instruments I have are not measuring correctly the blue color, it's impossible that the osram array is emitting in 400 or 410 nm. I would need a spectroradiometer to get reliable measures. But it is true that the blue color and saturations have a slightly purple tone. I hope with the nichia array rated at 455nm can be improved a bit. I would need someone help to get an accurate calibration, any ideas? :)
For final calibration I will create a 3Dlut for madvr to get a decent gamma traking and color saturations, but I have to solve the isues with the blue measurements.

I don't know what is the exact light output, but I suppose is around 1000 ANSI lumens. Here yo have a photo, I'm measuring 70 foot lamberts in a 65" screen, with this number I can extrapolate to my final goal, it will be 12 ftl in 145". I can increase the output power, but I have to test its reliability. I am interested in seeing that there is no loss of light performance during many hours of operation.

Calibration target 2.jpg
 

HDMaster

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Disassembling the complete projector is no problem for me.
I was in my last job technician for projection systems.
My Sony has been disassembled a lot of times for cleaning by me.

Only by rising the size of it i can handle cooling and the noise.

Your way is really cool.
It seems that your construction would be a choise to construct a kit for other projectors.
 




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