open can?

[Skram0]

Okay, I did some experimenting. Found if you hold the pins pointing up and that little nubbin on the casing (visible in my pic) pointing toward you, then center is ground and the left is the red LD. I first was using my radio shack 6v lantern battery. At first I was limited by my DDL driver and the resister I had used, so I jumpered it with a wire as if it wasn't there. Then I was limited by the 6v battery, so I used the 12v from the comp molex connector. I tie wrapped a small chipset heatsink to the LM317 with some thermal grease, but that started to get hot over 200mA so I used a CPU fan to cool the heatsink which kept it very cold at all currents.

Lase @ 55mA
255mA @ 2.745v
322mA @ 2.856v (4.99v @ 6v battery)
457mA @ 3.075v (used 12v here and after)
550mA for about 20 seconds but the LD started to get really hot

I didn't have any heatsinking on the LD but just the metal vise holding it steady. Around 450mA the LD was pretty hot to the touch, it would hurt if I pressed my fingers a bit. I tried to hold an AixiZ focus lens to simulate a focused dot, but I don't think 100% light was going through the small entry hole of the lens module. So probably no matter how bright it gets, only a certain amount can fit through the hole. Probably need to drill it out or use alternative lens methods. If I waived my arm over the beam I could sense a slight rise in temperature a few inches away from the module. The beam is very elongated, so if any focusing is desired, then you'd need the maximum input width possible.

I don't own a power meter. But I'll have to take some pics later next to my GB @ 180mA.

 

[Benm]

Lase @ 55mA
255mA @ 2.745v
322mA @ 2.856v (4.99v @ 6v battery)
457mA @ 3.075v (used 12v here and after)
550mA for about 20 seconds but the LD started to get really hot

550 mA sounds like a hell of a lot of current - is it still alive?

The case is odd for sure, but it looks like it would be possible to mount a heatsink of some sort using the flanges on the sides with some little bolts and nuts. Fitting a lens would be more difficult, but perhaps worth the effort consindering the amount of current it can handle - assuming power ouput is as good as you'd expect at 500 mA...

 

[phenol]

550 mA sounds like a hell of a lot of current - is it still alive?

I would assume those /+ open-cans/ 18-20x LDs are rated for ~350mW pulse or ~130mW CW @ 75C. 550mA does indeed sound like pushing it off the cliff to COD within minutes/hours of brilliance, but with proper[active] cooling...who knows :

 

[Skram0]

550 mA sounds like a hell of a lot of current - is it still alive?

Yea, it's still alive and kicking. I'll have to rig a heatsink on the LD module and get some active cooling on it. Maybe run it constantly for a few days around 500mA. Guess I wouldn't mind much if it does die. At least we'll all have learned its limits.

It's amazing how much it lights up my hand when it's in the way of the unfocused beam. The ceiling gets a large red spot, mainly the center of the beam that hasn't dispersed in other directions yet. If the whole rectangular part of the beam can be harnessed, this thing would probably start a fire.

btw, sorry for hijacking this thead as this is kinda off topic. :

 

[Skram0]

Now it's amazing how much it doesn't light up my hand. :-/ Everything ran cool, except for the trim pot which was warm to hot since it's rated at 500mA. I attached a heatsink to the LD too and with air cooling on both vreg and the LD I let it run @ 450mA for 2 hours. Sometime within those 2 hours it had died. I think I hear the sound of taps faintly in the background...

Note to self, don't run open frames @ 450mA.

 

[Gazoo]

Thanks for all the data and info. It's hard to say, but the 20 second run at 550ma's may have shortened the life of the diode. I think I will stick with open cans and not try an open frame. Since your diode was so unique, I suggest you give it a proper burial so it may rest in peace. :'(

 

[Skram0]

Thanks for all the data and info. It's hard to say, but the 20 second run at 550ma's may have shortened the life of the diode. I think I will stick with open cans and not try an open frame. Since your diode was so unique, I suggest you give it a proper burial so it may rest in peace. :'(

So what's a good stable power you run the open cans at?

 

[Gazoo]

350ma's. You can go as high as 400 and I do believe the diode will last awhile as long as the duty cycles are kept short. The one I killed running at 600ma's may have had an early death because I was running it more than 5 minutes at a time. Even though I was using a TEC, it suffered from COD. I sure do miss my 350mw's..but I am happy with the 250mw's I am getting running with 350ma's. This is with a glass lens. With an acrylic lens the power is around 225mw's. Running at 400ma's will give you 300mw's using a glass lens. So with the acrylic lens it should be in excess of 250mw's.

 

[Skram0]

Now that it's dead, let the autopsy begin. [smiley=evil.gif]
With a little pressure, the inner popped out.

 

[phenol]

hey, dont tear it to pieces! you havent fried the IR half yet. give it a go.