SenKat
Enlightened
Firefly - post some PICS !!! I wanna see it ! :rock:
Blu-Ray laser diode hack
- Thread starter sysadmn
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Corona
Enlightened
I'm working on a blu-ray based pointer similar to these (for another member) and should have something to show by next week. I have some ideas for improving the finished appearance and improving the heatsinking of the brass module. Stay tuned...
One thing I have found is that the $4 Aixiz modules have a pretty solid APC driver on them, they seem to set the crappy little 650nm red laser diode (open die, no window in these 5.6mm cans) just above it's lasing threshold - about 20mA. Yep that's a really low lasing threshold!
I have 5 of them to let the smoke out of (gonna make some violet and DVD reds using these as the mechanical and optical laser mount, so the OEM red diodes are basically cannon fodder).
So I'll be doing a bit of reverse engineering on that Aixiz driver as well, at the very least I'm gonna figure out how to get that cheapo red diode bumped up to 50mA or so.
It MIGHT even make a decent driver solution for the blu-ray diodes, with a little modification. An APC for the blu-ray would be nice. Definitely gonna proceed with extreme caution there, and only after I have one that belongs to me
One thing I have found is that the $4 Aixiz modules have a pretty solid APC driver on them, they seem to set the crappy little 650nm red laser diode (open die, no window in these 5.6mm cans) just above it's lasing threshold - about 20mA. Yep that's a really low lasing threshold!
I have 5 of them to let the smoke out of (gonna make some violet and DVD reds using these as the mechanical and optical laser mount, so the OEM red diodes are basically cannon fodder).
So I'll be doing a bit of reverse engineering on that Aixiz driver as well, at the very least I'm gonna figure out how to get that cheapo red diode bumped up to 50mA or so.
It MIGHT even make a decent driver solution for the blu-ray diodes, with a little modification. An APC for the blu-ray would be nice. Definitely gonna proceed with extreme caution there, and only after I have one that belongs to me
SenKat
Enlightened
Excellent news ! Keep posting updates !!!
Corona
Enlightened
A few things others should know about
1) The MXDL 1W boost is voltage regulated at just <5V, so there is no hope of adding any precision current limiting circuitry to it with a blu-ray diode, due to the voltage drop of the diode. There just isn't any headroom for the current limit circuit to operate. For DVD reds, there are options, which I'll explore later (in that other thread I suppose).
2) The blu-ray diode threshold is right around 30mA. I ran it up to 35mA and it looks pretty good, ramped it up to 45mA on my laser diode supply (small current limited, precision DC supply I made) and it appears that 40mA is about the limit, at least for this particular diode.
3) Since the boost is regulated, a resistor is all that is needed to set the laser diode current. Low value resistors are needed because of the small voltage headroom. With a 15 ohm, this diode was below threshold. A 10 ohm got me to about 30mA and a 7.5 ohm to 35mA (approx).
Your results may vary so ALWAYS measure the current when testing your diode (the boost is likely to be loosely regulated, tolerances etc)
4) A .015uF or larger capacitor across the LD is a good idea and I recommend soldering it right to the back of the LD (or board remnant). Also a good place to attach the supply wiring.
5) It's a bear pressing that blu-ray diode into the brass housing, and the board remnant should be removed prior to doing so, or you risk damaging the laser diode. The one I am working on had the board slightly tilted and not flush to the back of the LD, so I carefully cut it into sections with an X-acto knife and removed it completely.
I have it mostly together, running at 35mA for now. I'll be sourcing some other resistor values and tweaking to get it to 40mA.
I have worked out a way to allow focusing the module without disassembly, by using the flashlight body's forward section (that unscrews), ala a MagLight.
Taking plenty of photos and I'll put something together as I complete the mechanicals. There will be some chuckles over one solution I devised...
1) The MXDL 1W boost is voltage regulated at just <5V, so there is no hope of adding any precision current limiting circuitry to it with a blu-ray diode, due to the voltage drop of the diode. There just isn't any headroom for the current limit circuit to operate. For DVD reds, there are options, which I'll explore later (in that other thread I suppose).
2) The blu-ray diode threshold is right around 30mA. I ran it up to 35mA and it looks pretty good, ramped it up to 45mA on my laser diode supply (small current limited, precision DC supply I made) and it appears that 40mA is about the limit, at least for this particular diode.
3) Since the boost is regulated, a resistor is all that is needed to set the laser diode current. Low value resistors are needed because of the small voltage headroom. With a 15 ohm, this diode was below threshold. A 10 ohm got me to about 30mA and a 7.5 ohm to 35mA (approx).
Your results may vary so ALWAYS measure the current when testing your diode (the boost is likely to be loosely regulated, tolerances etc)
4) A .015uF or larger capacitor across the LD is a good idea and I recommend soldering it right to the back of the LD (or board remnant). Also a good place to attach the supply wiring.
5) It's a bear pressing that blu-ray diode into the brass housing, and the board remnant should be removed prior to doing so, or you risk damaging the laser diode. The one I am working on had the board slightly tilted and not flush to the back of the LD, so I carefully cut it into sections with an X-acto knife and removed it completely.
I have it mostly together, running at 35mA for now. I'll be sourcing some other resistor values and tweaking to get it to 40mA.
I have worked out a way to allow focusing the module without disassembly, by using the flashlight body's forward section (that unscrews), ala a MagLight.
Taking plenty of photos and I'll put something together as I complete the mechanicals. There will be some chuckles over one solution I devised...
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Corona
Enlightened
OK it's done. I like it - and think others will also...
Completed unit...sweet looking flashl...ahmm..LASER
Without aperture cap, see how nice and clean it is inside...except for the fuzzy on the lens (macro photos show too much!)
Yes you can adjust the focus by rotating the front hood. Very cool and I'm sure others will follow suit.
Here's the procedure (PDF file) with plenty more photos. Sorry, no beamshots as I was up late enough as it is finishing this
Note there are also some hints on modding the boost circuit to increase the voltage. There are better / more precise ways that what I did, but it suffices for this project.
(LINK DELETED BY CORONA)
Completed unit...sweet looking flashl...ahmm..LASER
Without aperture cap, see how nice and clean it is inside...except for the fuzzy on the lens (macro photos show too much!)
Yes you can adjust the focus by rotating the front hood. Very cool and I'm sure others will follow suit.
Here's the procedure (PDF file) with plenty more photos. Sorry, no beamshots as I was up late enough as it is finishing this
Note there are also some hints on modding the boost circuit to increase the voltage. There are better / more precise ways that what I did, but it suffices for this project.
(LINK DELETED BY CORONA)
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Corona
Enlightened
Try it now I fixed the link to an http link (sry)
SenKat
Enlightened
That has GOT to be the most in depth walk through I have ever seen ! THanks, man - gives new hope to the Elly's sitting here, gathering dust...now, to find a CHEAP blu-ray diode....
Corona
Enlightened
Thanks for the kind words, I try to document these efforts so others can benefit.
[edit]By the way, I fixed the arrow location in the PDF, it was a smidge off (conversion error from Word to PDF). Updated the link and PDF filename, is you don't have Rev1, go get it and trash your old copy...[/edit]
And thanks really should go out to toyman for initiating this project and trusting me with his BR diode and a couple different flashlights, while I sourced parts, developed concepts, and put it together. He's been very patient over the past 2 weeks... I'll be shipping this one back to him in the next day or so and then working on another for him, and finally, one for myself.
I will be looking for some more Ellys for future projects (DVD red for sure) as well as looking for improved optics for these violets. Any suggestions or surplus stuff, trade arrangements, etc. are open to discussion.
Feel free to PM me with any side project ideas, I can't do mass production but I will always dive into something interesting.
[edit]By the way, I fixed the arrow location in the PDF, it was a smidge off (conversion error from Word to PDF). Updated the link and PDF filename, is you don't have Rev1, go get it and trash your old copy...[/edit]
And thanks really should go out to toyman for initiating this project and trusting me with his BR diode and a couple different flashlights, while I sourced parts, developed concepts, and put it together. He's been very patient over the past 2 weeks... I'll be shipping this one back to him in the next day or so and then working on another for him, and finally, one for myself.
I will be looking for some more Ellys for future projects (DVD red for sure) as well as looking for improved optics for these violets. Any suggestions or surplus stuff, trade arrangements, etc. are open to discussion.
Feel free to PM me with any side project ideas, I can't do mass production but I will always dive into something interesting.
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Kenom
Enlightened
So corona, given your walk through and someone following your steps what is total cost of putting one of these together including average cost for a sled on ebay. I've seen the sleds for around $80 with 15 shipping. the "elly" on DX costs???? and you did a bang up job on that front bezel. Looks awesome.
Corona
Enlightened
I think the Ellys are around $5 a pop. Don't know exactly as I have not had to source them myself, yet. But there's threads on modding these into better flashlights over in the LED CP forums, with cost info...I'm sure another member can answer this better
The parts I added are dirt cheap, the stainless washer and grommet are both ~40¢ each
Plastic CD spindle washers are "free"
1N4148 diode, ceramic capacitor - a few cents
The Jefferson Washer - exactly 5¢
I'd guess it's right around $105.05
The parts I added are dirt cheap, the stainless washer and grommet are both ~40¢ each
Plastic CD spindle washers are "free"
1N4148 diode, ceramic capacitor - a few cents
The Jefferson Washer - exactly 5¢
I'd guess it's right around $105.05
hank
Flashlight Enthusiast
> "near UV is absorbed by the cornea.. "
Nowhere near all of it.
http://www.mdsupport.org/library/hazard.html
http://scholar.google.com/scholar?sourceid=Mozilla-search&q=blue+light+risk+macula+damage
Nowhere near all of it.
http://www.mdsupport.org/library/hazard.html
http://scholar.google.com/scholar?sourceid=Mozilla-search&q=blue+light+risk+macula+damage
Corona
Enlightened
Hey - for those who downloaded the PDF - I took it down as I need to make some corrections to it. Adding the 1N4148 diode works fine to raise the boost voltage but because it is in series with the supply lead to the little boost controller, it drops the initial voltage from 1.5V to about 1.2V.
I experienced start-up problems with anything but a brand-new AA cell and this is unacceptable so I'm tweaking the design a bit to just work off the 5V. Essentially is is a matter of reducing the resistor value to something in the 1.2 - 1.8 ohm range. I prefer to use a bit bigger "ballast" resistor, but until I figure out a simple way to get the boost to start with a diode drop in there, we're back to square one.
Sorry folks, I'll post another update when it's all straightened out...
OK - follow this link to a post / thread I made just for this thing
I experienced start-up problems with anything but a brand-new AA cell and this is unacceptable so I'm tweaking the design a bit to just work off the 5V. Essentially is is a matter of reducing the resistor value to something in the 1.2 - 1.8 ohm range. I prefer to use a bit bigger "ballast" resistor, but until I figure out a simple way to get the boost to start with a diode drop in there, we're back to square one.
Sorry folks, I'll post another update when it's all straightened out...
OK - follow this link to a post / thread I made just for this thing
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