DIY LPC-815 @ 500mA in Ehgemus host.

[gillza]

Dear forum members,

I am a new member here and just recently have assembled my first laser pointer following i-hacked guide (blu-ray in Dorcy Jr.), and today I need your suggestions/advice/comments regarding my current project.

Next week or so (payday is this Friday ) I'm planning on putting together a Red laser "pointer" using recently acquired LOC-815 diode (have 5 of them, thanks Styropyro).

Parts that I will use:
LOC-815
Module: Aixiz (ordered)
Driver: FlexDrive v5 (yet to order, will set myself to 500mA)
Host: by Ehgemus: Host Easy Build (yet to order).
Lense: 650-G-1 mod by jayrob (not sure if I'll be getting it, a bit expensive)


A couple of questions that I'm hoping someone will answer:
As I understand (from searching here) 500mA current is pushing the diode quite a bit, will the heatsink in the host I mentioned be enough to dissipate enough of the heat from it?
A question for Ehgemus if he reads this thred: Can the heatsink in that host be replaced with a copper one? (is it necessary?)

Please if you have any other suggestions/correction don't hesitate.

Thank you.



P.S. The build is complete:

http://laserpointerforums.com/f51/d...build-host-flexdrive-v5-55565.html#post783474

 

[styropyro]

Just some advice, these LOC laser diodes are very easy to destroy when extracting, with everything being exposed stuff goes wrong. I've destroyed my fair share of these in the past and finally have the technique down.

Here's a good video showing extraction:


Cut the heatsink completely off, do not twist the halves of the heatsink at all like we do with PHR-803T sleds.

If you end up not being able to afford the 650-G-1 lens, the next best thing would be a glass lens from Aixiz. At 500mA you will want a lens with minimal reflectivity because a half an amp is really pushing these things.

If you follow somewhat decent duty cycles you will be fine with the heatsink you have.

Post pics when finished!

 

[gillza]

Styropyro,

Thank you for the reply!

I did extract the diode in similar fashion, filed as close to the diode as I could but then I had to use two pliers to open the heatsink apart anyway. The diodes from the sleds I got had a "roof" unlike the one shown in this guide, so there was a chunk of alloy still present that would prevent me from popping the heatsink apart with a screwdriver or such. I had to use the pliers.

Two diodes were extracted this way. I have carefully wrapped them in antistatic bag (was careful not to touch the wires to the semiconductor) and store it in the same box that my blu-ray diode came from hightechdealz in

 

[Meatball]

500ma is definitely pushing it. At 500ma, it will not put out much more than if it were at a more reliable 420ma. If you really want that extra powa back, you WILL get it from the 650-G1. I use that lens myself, and I have to say that it does work as advertised!

 

[gillza]

500ma is definitely pushing it. At 500ma, it will not put out much more than if it were at a more reliable 420ma. If you really want that extra powa back, you WILL get it from the 650-G1. I use that lens myself, and I have to say that it does work as advertised!

I see, 55$ is a significant chunk of money for me would 450mA be a "healthier" current?

According to the picture below ( (c) Dr. Lava ) in order to reach 300mW 500mA is what I should be aiming at That is where I got the numbers from.

 

[styropyro]

He was probably using an acrylic lens. With a good lens, you will be near 300mW at 420mA.

 

[Meatball]

Correct! At 416ma, my LOC is lasing through a 650-G1 at 312mw. 420ma is the recommended maximum current that also comes with a reasonable lifetime.

 

[styropyro]

So at the expense of a shortened lifetime, you could push 350mW+ at 500mA. And if it dies, you have four more!

 

[gillza]

You guys have convinced me. I will get the lens from jayrob and will put the diode to a moderate current this time. Next paycheck I will build another pointer and try to set the current to 500mA to see how it goes.

 

[gillza]

Well most of the parts are ordered.
I could not order Flexdrive at Dr.Lava's site since it showed as out of stock and in the moment of panic instead of doing proper googling I ordered microboost drive. Only later i've found flexdrive available at "laser surplus parts" and got one from there. So I guess just for curiosity's sake i will try to power the diode using microboost and see of it will last, if not i'll switch to flexdrive.

Waiting for host and drivers to arrive.

P.S. I've found a thread with recommendations to use Silicone Wire that Flaminpyro sells (waiting for his reply) and I plan on using it for my next build (or this one maybe too).
P.S.S. I dont have a camera but just upgraded my phone to Samsung Vibrant and will be using it to capture some pics

 

[rockz]

That flaminpyro wire is awesome. I use it for everything, the silicone insulation doesn't melt, they are stranded, and are very flexible.

 

[gillza]

Except that I can't seem to get a reply from him...