Midsubishi 635nm 300mW temperature testing

[justinjja]

These diodes seem to really like being cold.
Testing done at 1.4A. w/ a 650 G2 lens
Diode is attached to a 20w Tec running at ~1/2 power.

You can probably tell when I turned the tec on

 

[kiyoukan]

can you get a test done just like that but with temp readings?

 

[justinjja]

I took some temp readings from the top of the module,

starting temp: 25c
highest temp (when the output was droping off) 30c
then i turned the tec on, temps started droping, output started increasing,

Temp got down to 10c

 

[kiyoukan]

you said you were using a 20W tec what size and driving at half power you only could keep it at 25C? i was thinking of building a tec driver and driving mine down to around 16C

 

[justinjja]

starting temp was with tec off,
it got down to 10c with the tec turned on

Here is a link to the tec i was using
and i was driving it with a single 18650

 

[kiyoukan]

Would you mind doing a long reading with it cooled to 16C?
And maybe a bit less current lol around 850?
i dont have a usb meter so its hard to make a chart but im building the dual setups and i want to have a thread with as much collected data.
I want to know if we get more power at 16C than 25C and how much.

 

[justinjja]

I need to buy/build my self a lab PSU

the datasheet gives you a fairly good ide of how temp / current / and output power relate

http://www.orthotoronto.com/detay/mitsubishi_laserdiodes_pdf/ML520G71.pdf

 

[Benm]

This is totally to be expected.

Cooling these lasers down will also result in shorter wavelengths that are more visible to the eye, so you should use TEC if you can

 

[borgqueenx]

Yeah the longer you go down the more visible, but i actually would like it to go a bit up. We want a red laser after all, not a orange one^^

 

[justinjja]

hard for me to tell by eye, but even cooled it is probably still around the original wl at these currents.