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ArcticMyst Security by Avery

Simple green Adjustable powersupply question.

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Im planning a build with adjustable power going into a red, blue, and green laser. I understand how to do it with the red and blue using potentiometers. But green has its own driver. So what do you guys suggest? Sorry if i make no sense, its past my bed time :tired:
 





anselm

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You'll have a hard time getting nice results with anything short of a lab module with analog modulation, and TECs to stabilize diode and crystal temperature.
Due to the DPSS process, it's not as simple as adjusting the diode's current.
 
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Hmm, the greenie is only a IR diode with crystals, etc.
The driver that it comes with is a voltage comparator that supply the current, it has a low dropout (and low cost) so with 3v you can run the driver @ full power. You can always use a LM317 driver and use the IR diode.
 
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But, regarding the crystal action, isn't there some power upper- and lower-limit on the crystals or something? Isn't that why we usually can't build green modules ourselves?
 

anselm

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Well you can adjust the current on most greenies, that's what people call
"pot-modding" (search for it). But the power is not going to change in a linear relation
with the that current adjustment, and it will most likely be unstable as the diode
and the crystal change temperature.

You can adjust the power of a greenie somewhat, but not very comfortably and gracefully.
 
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If I understand, you want to build one stick with three lasers in it, one red, one green DPSS, and one blue?? If you use one driver for the red/blue how are you going to switch diodes without blowing the driver?? (much less switch in the DPSS Green)?
Why not use seperate drivers for the red and blue, and parallel all three to your power supply, then switch on each driver as you need it? No resetting drivers, and no smoke (except what you might be trying to burn).
 
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Thats not what im saying?
Im going to make my own drivers for a red and a blue with adjustable power. I want that for the green to but i dont know how.
If I understand, you want to build one stick with three lasers in it, one red, one green DPSS, and one blue?? If you use one driver for the red/blue how are you going to switch diodes without blowing the driver?? (much less switch in the DPSS Green)?
Why not use seperate drivers for the red and blue, and parallel all three to your power supply, then switch on each driver as you need it? No resetting drivers, and no smoke (except what you might be trying to burn).
 
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Just limit the max current to the diode maximum, eg "don't overdrive the diode" and you should be fine. You only need crystal temperature control when it is too cold or too hot where you live, or the diode himself makes the crystals heat.
 

anselm

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An IR pump diode is just another laser diode like the other ones.
If you like, you can power it with a LM317 circuit of your own like any other diode.

Remember this though:
-IR diodes have a forward voltage of ~2.2V, IIRC. Not that this would matter much for a LM317 driver.
-IR diodes are usually case positive. Unlike red diodes, which are usually case negative, and 445nm are case neutral.
 




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