20w coherent Will computer PSU work?

So its safe to assume I cant just hook it up to the 3v output, right? I need some form of regulation? Easy to build?

Guyfromhe said:

I was just wondering where the 650 watt number came from...

Click to expand...

I was looking around NewEgg, and I found a 650W PSU that had 34A on the 3.3V rail. Like I said, there's no strong correlation between these two figures, and you need to look at the individual rail's current capacities.

so here's how it arrived, wrapped once in copper, then in half of a pink bag, folded and boxed loosely with the crystal in a kinda bubble wrap roll. in pic # 4 you can almost make out a very small blue dot on the purple substrate. what are the 2 gray wires on either component, and what to do with them? I acquired 2 ATX PSUs and isolated the needed outputs. the 400w psu is 3.35v (dvm'ed) at 15a (rated), and a 300w at 3.45 (dvm'ed) at 30a (rated).

if I heatsink the diode and momentarily connect the power leads it should come to life, right? today is day 7 of a 7 day return option and I need to test the functionality.

the crystal looks to be just one piece, completely transluscent with a light blue tint to it. it is also sticking out of one side of its' mount (circled in red in pic)

thank you for all your insight, it is immensely helpful.

more pics

That's a nice diode. How do you intend on sourcing current through it? Just going use a big ol' power resistor directly off the rails? Or were you thinking of using any kind of voltage follower/ common collector amps in series?

5v1i5v0 said:

Hopefully, although the ebay listing had it as blue laser asy.

Click to expand...

The first pic you posted says 14W LBO Nd:YVO4 assembly. Getting blue out of any Nd doped crystals means you have a level 3 laser. Those have a high threshold and are very difficult to pump. You'd need a good beam quality of your pump, something a diode bar hasn't without any special optics.

5v1i5v0 said:

So its safe to assume I cant just hook it up to the 3v output, right? I need some form of regulation? Easy to build?

Click to expand...

I don't think you should take a project this big if you don't even know a laser diode needs a good filtered current regulation or it will die. Instantly.

5v1i5v0 said:

Anything like building small drivers like ddl etc?? Yes, I purchased googles for this for sure

Click to expand...

It's quite different from a DDL, completely different design.
You purchased google, that's not small.

5v1i5v0 said:

so here's how it arrived, wrapped once in copper, then in half of a pink bag, folded and boxed loosely with the crystal in a kinda bubble wrap roll. in pic # 4 you can almost make out a very small blue dot on the purple substrate. what are the 2 gray wires on either component, and what to do with them? I acquired 2 ATX PSUs and isolated the needed outputs. the 400w psu is 3.35v (dvm'ed) at 15a (rated), and a 300w at 3.45 (dvm'ed) at 30a (rated).

if I heatsink the diode and momentarily connect the power leads it should come to life, right? today is day 7 of a 7 day return option and I need to test the functionality.

the crystal looks to be just one piece, completely transluscent with a light blue tint to it. it is also sticking out of one side of its' mount (circled in red in pic)

thank you for all your insight, it is immensely helpful.

Click to expand...

The two small gray wires are from the thermistor in the diode bar.

5v1i5v0 said:

more pics

Click to expand...

It looks like you bought the crystal set from a 10mW 473nm Nd:YAG DPSS laser, a working complete laser can be bought for $55 from a cheap seller. I've bought similar diode bars for $30. I hope you didn't pay more than $150 for the set because these two are NOT going to work together. Also Nd:YVO4 lases on a different wavelength, so if I'm right this crystal set comes from the B&W tek 10mW 473nm lasers you have a Nd:YAG crystal set.

The diode bar has a terrible beam profile, it hardly looks lke a beam. A special fiber optics piece can give you something that can be focussed a bit more narrow. Blue lasers however need a good overlap between the pump beam and the cavity mode. A too large spot will be a waste of pump energy, a too small spot won't even let it lase.

Even if you could get a portion of the diode bar properly focussed, these crystals aren't made to sustain more than a few watts of pump power. The original pump was 1.4W. you can stretch this a bit but that's about it. With the original beam shaping optics of the blue laser you can one or maybe more emitters focussed in the crystal and maybe 100mW or more out. But in any case you need special optics to pump a blue laser crystal set.

If this was supposed to be a set, return it. You have bought a used diode bar with an incompatible used 10mW Nd:YAG crystal set.