Blu-Ray - Heatsink or no?

[mr.lazo]

I'm slowly cobbling together a 150mW blu-ray and was wondering if I'd be able to do it without installing a heatsink?

I'm trying to avoid it, if possible, because I won't have enough room for one in the current flashlight case I'm using to house the whole shebang.

Excuse my ignorance, but this is only my second project, and my first time working with anything with output that high (my first project was only 5mW).


Thanks!

 

[Krutz]

welcome aboard!

150mw output, or some 100s of mw electrical input are laughable for everyone except us laser-hobbyists ;-)
its not hard to keep your diode at reasonable temperatures, say, below 40°C. you dont need that much of a heatsink, its sufficient if there is a good thermal connection between the diode and the host. i assume the diode is in an aixiz housing? the best thing would be metal in between the aixiz and the host. if not possible, try washers. if nothing else works, mix epoxy with metalfilings or something. in short: avoid airgaps, no matter how thin! if you would put your 12mm aixiz into a 12.5mm copper heatsink, it would still overheat. put thermal paste in between, and you can run it as long as your batteries can.
another idea: solder! you can solder the aixiz housings, if nothing else works, fill the gaps with tin! and obviously insert the diode afterwards ;-)

manuel

 

[BuildAbluraylaser]

Like you, I had that dilema in my first build, but because of my host, I didn't install a heatsink. Yet, I had no problem with my diode set at 75 mA for 50mW (the max outpout of my diode) when it came to heat. Here's some pics of my build (blu-ray)

As you see, no heatsink. It barely heats up after 3 mins.

 

[mr.lazo]

Thanks a lot guys!

That makes me feel a lot better about the project.

I think I'll cut down some washers to fit and fill in any gaps between the housing/washers/host with some arctic silver.

;D

 

[benmcntsh]

Not to mention that you probably won't be having the beam on continuously for minutes at a time. In only a few seconds, any metal the diode is touching will be happy to absorb a little more heat.