Saabluster's R&D

saabluster

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This thread is going to be a catch all for some small insights of things I am working on. Given the sensitive nature I will not be revealing all the details of how or even what is being done. But I thought some may be interested to have a little peak at what I am working on in general.

I am attacking this problem of improving the state of the art from many many angles. Since I cannot alter or create epi layers I am focusing on thermal and optical modifications as well as developing ways to mix and match LED's constituent parts from end products. This means finding ways to remove or alter encapsulants. Remove and alter phosphor layers. Remove LED dice. As you can imagine trying to tear apart an end product can be tricky to do without damaging the underlying structures such that they can be used again. So I spend copious amounts of time developing theories and then testing those theories. I am a mass murderer of LEDs. Hundreds of LEDs have been slaughtered over the last few months. It is expensive but the only way to move forward.

I hope you find this thread interesting.


This is a Nichia 219C. One of the things I work at is getting the various layers to separate where I want them too. In this case I wanted to split the encapsulant off the phosphor layer. This LED is particularly difficult to do this with. This picture shows a near perfect separation.
C5F7B143-D0EA-4307-8711-4C66C7922D36_zpspm9wpinn.jpg
 

saabluster

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I have done a lot of work in removing phosphor layers so that they can be transplanted to new devices. I have perfected a way to remove old school Cree phosphors perfectly intact.

4506C41D-696A-4988-86C5-777F2BB055C4_zpso2ovos5q.jpg
 

saabluster

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This is work into modifying the phosphor itself. The left is the OEM. On the right is one I have modified to increase surface scattering.

646D7214-1388-4304-B3A6-3D4FB318FBE6_zpsx81a5wwk.png
 

noboneshotdog

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Wow! You are SICK! And I mean that in the most EPIC of ways. Didn't know anyone even concidered this approach. Magnificent!
 

egginator1

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That's very interesting......but leads to so many questions....I'm looking forward to chapter 2..!
 

Enderman

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Hey saabluster have you looked into single crystal phosphors?
Several universities have published research papers on YAG:ce phosphor crystals and using blue lasers to hit the crystals and make light.
The crystals have high thermal conductivity and can survive 300C without losing output.
Depending on how small you can get the crystal, it might be a better option than using the typical powdery mix that LEDs use.
It does require a blue laser though.

Here are the articles so you can read about it and maybe give it a try:
http://spie.org/newsroom/6288-single-crystal-phosphors-for-high-brightness-white-lighting
https://www.osapublishing.org/Direc...-24-2-A215.pdf?da=1&id=333666&seq=0&mobile=no
http://projects.itn.pt/marco_fct/[1]Ga2O3%20and%20single-crystal%20phosphors%20for%20high-brightness.pdf
http://jss.ecsdl.org/content/5/10/R172.full

There are more, but those you need to either pay or be part of a university to be able to see.
 

saabluster

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Hey saabluster have you looked into single crystal phosphors?
Several universities have published research papers on YAG:ce phosphor crystals and using blue lasers to hit the crystals and make light.
The crystals have high thermal conductivity and can survive 300C without losing output.
Depending on how small you can get the crystal, it might be a better option than using the typical powdery mix that LEDs use.
It does require a blue laser though.

Here are the articles so you can read about it and maybe give it a try:
http://spie.org/newsroom/6288-single-crystal-phosphors-for-high-brightness-white-lighting
https://www.osapublishing.org/Direc...-24-2-A215.pdf?da=1&id=333666&seq=0&mobile=no
http://projects.itn.pt/marco_fct/[1]Ga2O3%20and%20single-crystal%20phosphors%20for%20high-brightness.pdf
http://jss.ecsdl.org/content/5/10/R172.full

There are more, but those you need to either pay or be part of a university to be able to see.

Yes. Been there done that. Lasers and all. ;)

This is a single crystal phosphor. The one on the left is stock. The one on the right was modified by me to increase surface scattering. This gave a decent improvement in intensity.

2AC126DE-952A-4ABC-9FE9-D5D00A49C5EF_zpsbaf5k7xi.png
 

Enderman

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Yes. Been there done that. Lasers and all. ;)

This is a single crystal phosphor. The one on the left is stock. The one on the right was modified by me to increase surface scattering. This gave a decent improvement in intensity.

Using a laser should give much higher intensity than the blue light from a regular LED no?
How many watts of blue lasers have you tried and did you heatsink the crystal using some arctic silver thermal adhesive?

There are some good 15W engraving lasers on ebay, the advantage of lasers over a blue LED die is that you can direct multiple lasers at the same phosphor and increase the intensity.
 
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saabluster

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Using a laser should give much higher intensity than the blue light from a regular LED no?
How many watts of blue lasers have you tried and did you heatsink the crystal using some arctic silver thermal adhesive?

There are some good 15W engraving lasers on ebay, the advantage of lasers over a blue LED die is that you can direct multiple lasers at the same phosphor and increase the intensity.

The laser gives way higher intensity yes. But the legal issues surrounding lasers in the US have kept me from pursuing a salable product. All my work has been under 2W. Not much in the grand scheme of things but you dont need much power to tackle engineering problems. Just focused it real tight to probe the limits on power density. I worked a lot on creating a setup that did not have thermal quenching issues as I found out early on that had to be faced head-on.

LEDs can be combined as well. They just don't scale as far or as efficiently.
 

saabluster

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One more treat. I developed a new method for dedoming especially difficult LEDs. Here are several LEDs that are notoriously difficult to dedome. Left to right-XPL2, XHP35, Oslon Square, Oslon Square. With my processing the XHP35 has higher intensity than the vaunted XPG2 S4.

37557BF5-EC7A-4567-B006-082468CD0097_zpsqvxfptxg.jpg
 

Enderman

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The laser gives way higher intensity yes. But the legal issues surrounding lasers in the US have kept me from pursuing a salable product. All my work has been under 2W. Not much in the grand scheme of things but you dont need much power to tackle engineering problems. Just focused it real tight to probe the limits on power density. I worked a lot on creating a setup that did not have thermal quenching issues as I found out early on that had to be faced head-on.

LEDs can be combined as well. They just don't scale as far or as efficiently.
Ah ok.
One of the journal articles I saw tested and got a perfectly linear increase up to 14W of blue lasers and 4k lumens, I was wondering how much more wattage a crystal could take before getting to 300C.
Maybe 60W of blue lasers can make a 1mm crystal shine at 16k lumens? That would certainly be amazing :p
I'll probably get a sponsorship from my university and test this out a few years from now.

Where did you get your crystal from? Was it http://www.crytur.cz/ ?
 

ma tumba

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Speaking of lasers. I wonder if proper blending of r, g and b laser beams would do a better job for throw while formally providing white light? We are here not for great color rendering anyway
 

Enderman

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Speaking of lasers. I wonder if proper blending of r, g and b laser beams would do a better job for throw while formally providing white light? We are here not for great color rendering anyway
I thought about that, but even though the colour isn't that important there would be a lot of grain/noise, because when you expand a laser beam (to get a usable spot size) it looks like this:
arc4-5.jpg

Which is honestly pretty unusable imo.

Maybe higher quality lasers have a more uniform spot? idk
 
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