I'm looking at getting some of the diodes rated at 100W - would it be safe to underpower these (same input voltage, low current) as a means to control the output intensity? I'm going to use them as pumps for a fiber laser and though it will be rated at 400W I would like to have better variation than 100W steps.
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Underpowering a 910nm 100W pump diode
- Thread starter CoryG
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Almost any Diode Lasers max power can be dialed down to
lower powers by decreasing it's drive current.
Jerry
You can contact us at any time on our Website: J.BAUER Electronics
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Thanks, that is what I had suspected but wanted some degree of confirmation before attempting it and possibly burning out some expensive diodes.
I attached a PDF of the part I'm going to be using (couldn't find a link to it online anywhere) - if anyone is interested I'll send you the contact info of the sales rep I've been speaking to.
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That s NOT a Laser Diode... That is an LED.
Reading the specs you can easily see that the Max Current
for that device is only 350mA...
There is no way it will produce 100W of Laser light or 100W
of any wavelength of light...
Jerry
You can contact us at any time on our Website: J.BAUER Electronics
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Like lasersbee said yes you can under drive any diode without problems. However depending on the application you may want to consider that under driving may cause the wavelength to shift. The same goes for over driving as well. If that's not of concern then the next thing you should look into is the lazing threshold. If you try to run the diode under its threshold it may not power up. Check your data sheet beforehand to make sure.
Otherwise you should be fine.
Otherwise you should be fine.
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Tolerance of measurement of peak Wavelength ±2.0nM
The spec sheet says wavelength +- 2nm, that seems to imply that it is a laser diode, unlikely that an LED can produce that kind of output.
Or the maker could simply be pulling it from their rear. I certainly agree that it looks far more like an LED.
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Laser Diodes have specs for Threshold Current and Output Power
in mW. This device does not...:undecided:
Jerry
You can contact us at any time on our Website: J.BAUER Electronics
It's an array of LEDs in a single package - it is not a laser diode but it is a diode I can use as a pump. You don't need laser diodes to pump a laser with.
It has 100 elements rated at 1000mA for the pulse forward current.
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100W is input power, not output power. And that's Chinese watts, not real watts. 350mA per die at 1.3V per die times 100 dies is closer to 45W.
Spectral bandwidth is 60nm, which means the light is spread 30nm on either side of the 910 central wavelength.
I'm not sure why they have two different ratings for radiant power, but it looks to be 2.25W per string of 10, although 50% efficiency is a little optimistic.
I really don't think the power density is high enough to use this as a pump. You cannot focus it either because of the massive emitting area.
What is the lasing medium?
Spectral bandwidth is 60nm, which means the light is spread 30nm on either side of the 910 central wavelength.
I'm not sure why they have two different ratings for radiant power, but it looks to be 2.25W per string of 10, although 50% efficiency is a little optimistic.
I really don't think the power density is high enough to use this as a pump. You cannot focus it either because of the massive emitting area.
What is the lasing medium?
If that's the case I may need to keep looking. I'm using Yttrium-doped fiber as the lasing medium so 30nm pretty much fits the curve, though I would like to get closer to 15nm. I'm looking at some pigtailed GRIN lenses as the input aperture for the fiber - do you know a good method for loosely collimating multiple light sources? It looks like no matter where I look 100W is about the best I'll get from a single light source and my target is 200W minimum, 400W ideal maximum.
An update on this - I inquired about the rating and was told the PDF had a typo - I attached the new one they sent me. They quoted me $530 for 10 pieces or for a single piece if I order 10 (waiting on clarification before deciding whether or not I want to place the order).
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Heheh, since when is IR good for sterilization?
Probably just a generic PDF with data changed around - but definitely not ordering from them. Apparently the "$530/PCS" bit that had me confused actually meant to say "$530/PC" in the original and 2 subsequent emails. Can definitely find cheaper, even if I have to hand-solder some SMT LEDs.
