Two Beauties on the way from Jordan.

[paul1598419]

The wavelength change is most obvious at very high currents on these diodes. If you don't mind the risk of it popping I'd go for 2.8A. I have one at 2.8A and another at 1.8A, the color is completely different. I'll probably make a thread about mine when I get some free time.

You don't actually expect that 7675 to last long at 2.8 amps, do you? I don't know yet, but I think that the WL sift will be pretty close to the same if driven at 2.4 amps or 2.8 amps. I will check that theory out when I get my build done and can measure the difference. If I'm right, the extra 400 mA will be doing nothing more than reducing the life of the diode.

 

[Atomicrox]

I don't expect it to last long, but it'll be worth it! Unfortunately the last 400mA makes the most difference. See my build here: http://laserpointerforums.com/f40/tunablue-wavelength-tunable-blue-laser-101135.html

 

[badboybilly]

You don't actually expect that 7675 to last long at 2.8 amps, do you? I don't know yet, but I think that the WL sift will be pretty close to the same if driven at 2.4 amps or 2.8 amps. I will check that theory out when I get my build done and can measure the difference. If I'm right, the extra 400 mA will be doing nothing more than reducing the life of the diode.

I can't wait to see your results Paul,
There are threads on this diode pushed and 2.8a is the best current for 473-476
Even Jordan has these pushed hard,
You did only pay $30 a diode, What's the issues, Anyway some more data on this diode can't hurt!


Edit, The shift is even more when warm.

 

[badboybilly]

I don't expect it to last long, but it'll be worth it! Unfortunately the last 400mA makes the most difference. See my build here: http://laserpointerforums.com/f40/tunablue-wavelength-tunable-blue-laser-101135.html

Yes awesome there we have it!
I can see the change with my eyes no need for a spectrometer!


Oh man how did I get here, I just noticed this is Andrews thread, Awesome buddy sorry for high jacking, You've been spending a lot on lasers lately ha! I haven't had the pleasure yet with this diode your getting!

 

[RedCowboy]

This one looks like output power was topping out around 2.1a now there could be color shift past 2.1a but how long before output power actually starts to drop, and how far does that line move when hot rather than cold?

I know the 7875 runs best at 2.4a but diodes vary, there are freaks and weaks so it's a matter of finding a balance, of course if you don't care about the price of replacing a diode then go for it, but there has to be a recommended max that a 6 month old diode with some time on it won't be driven past the knee, or dim down as it warms up.

I originally thought the 7875 was 2.4 max and 7675 was 1.8 max but 2.8a seems high for either one, again this is not what a brand new diode will take but what how a diode will fare over its lifespan for those who pay 60 dollars a diode and want them to last, of course you can do whatever you want with yours, I had thought the max suggested was 1.8, even DTR's EBay add stops showing results at 1.9a.....maybe if the operator never gets the unit more than a little warm then overdriving is not so bad, maybe 1.8a is the safe for everyone setting, I am curious to see where the 7675 starts to fold back.

 

[Atomicrox]

I think mine started to fold back slightly after 2A, but I'm not sure of the exact number. Anyways it's not a very efficient diode, it peaks at 1.5W with a 3 elements lens.
Also I don't use it all the time like you do with your lasers, if I did it'd probably die quickly.