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3x 445nm LD PIV Plot

DrSid

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Hm .. do I understand it correctly that with 4.5V direct drive it will stabilize around 1000mA ?

I mean direct direct, not even a resistor, maybe some capacitor to protect the LD from voltage peaks from the battery.
 



jayrob

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I'm preparing another "murder experiment" for these diodes, but i didn't get very far cos i was on vacation.

But once everything is up and running i'll start a testing thread, altho i won't be doing the many replots i did with the previous two. It's simply too much work - it'll be a simplified lifetime tests mostly just for the total lifetime.
Somehow I missed this thread...

Probably because I went camping and stuff...

But thanks for the graphs Igor!

Nice build you got there...
 

Bluefan

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Hm .. do I understand it correctly that with 4.5V direct drive it will stabilize around 1000mA ?
Nope, that's not the way to go. Take a look at the U vs I graphs. A slight change in current is an even smaller change in voltage. A small voltage change is a huge change in current. Just pick a 1000mA driver, works way better, safer and stable.
 

Tech_Junkie

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Somehow I missed this thread...

Probably because I went camping and stuff...

But thanks for the graphs Igor!

Nice build you got there...
Same here. Welcome back Igor.

I dont know about CW though. Mine is in a press fit diode housing, in an all aluminum host, and it heats up rather quickly at 1.1W. Unless you make a bigger host, with a TEC, or fan, I dont think its possible.

 

DJNY

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I also had a laser in the Ehgemus host (10x br) and it got warm very quick.

This is what IgorT explained me a while back:
...couldn't find an AixiZ module fat enough to establish a tight fit.

That's because the hosts are CNC machined with small tolerances and made with a 12mm hole.

And while the AixiZ modules are specified as 12mm OD, they are actually 11.88-11.94mm in diameter, so there is a gap left.

Unfortunatelly, when making a CNC heatsink or host, you have to have the hole made at 12mm, so that all AixiZ and Sure modules would fit in regardless of their varying OD....

Unfortunatelly this means that most of them will have a gap on the side, and only really touch the host on the opposite side of the set screw (where the set screw presses the AixiZ module against)...
 

Tech_Junkie

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Mine has the diode pressed into the top attachment. No AixiZ module, no gaps.

 

random person

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Your guys power calculations are confusing me abit. So at the max he showed on there was at 1.2A and a ~ 4.5V drop across the diode? So wouldn't that be 5.64watts? So... I'm assuming then thats not what his diode was actually emitting as light based power. The majority of that is going to heat right?

So using that efficiency plot of his it would be somewhere around 5.6 watts * .24 efficiency = 1.344 watts of illumination(not sure the proper verbiage there)? Is that correct or am i missing something?
 




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