Direct diode doubling

[absolom7691]

Let me see if I understand this process.... 5W 808nm Diode> lens> prism pair> lens> nd:YAG or nd:YV04> KTP> OC> IR filter. This is all very temperature sensitive, hence DPSS greens are touchy with modulation. Where is the temperature the most touchy? Is it the alignment of all the optics, the lasing meduim, or the KTP? If it is the KTP, then I can see why this won't work, but if not, why are we not direct diode doubling? Why not just do 3W 1064nm diode> collimator> KTP crystal > IR filter?

[-bart-]

A high-power 1064-diode (if it would exist) just isn't able to reach the the intra-cavity optical power density to achieve harmonic generation efficiently.

The components you describe are not magical frequency converters.
It's a d.p.s.s. laser, the one laser pumps the other, in which shg takes place.
The hr mirror is essential in the setup you describe.
1064-Lasing occurs between the hr and the oc, therefore the power density is very high.
Shg can be done outside the cavity, but only in pulsed mode to achieve the needed power density. The shg cristal needs a high power-density to be efficient.
Also the beam characteristics of the 1064/532 laser can be much higher than the pump laser. In the case of an average dpss laser the output beam looks a lot better than the pump beam.

[-bart-]

A high-power 1064-diode (if it would exist) just isn't able to reach the the intra-cavity optical power density to achieve harmonic generation efficiently.

The components you describe are not magical frequency converters.
It's a d.p.s.s. laser, the one laser pumps the other, in which shg takes place.
The hr mirror is essential in the setup you describe.
1064-Lasing occurs between the hr and the oc, therefore the power density is very high.
Shg can be done outside the cavity, but only in pulsed mode to achieve the needed power density. The shg cristal needs a high power-density to be efficient.
Also the beam characteristics of the 1064/532 laser can be much higher than the pump laser. In the case of an average dpss laser the output beam looks a lot better than the pump beam.

look at the laser faq, it tells you a lot more on dpss lasers.

[absolom7691]

I probably should have mentioned the HR. I didn't because in most lower power DPSS, the HR coating is on the nd:YV04. I now see what you mean about the density of energy, intracavity.

I guess the only way to get amazing modulation would be a 532 diode *laughs* or an AO mod on the green and just let it run. Otherwise, we are stuck with semi-fast greens with slight power flucuations. Thanks for the info.

[danielbriggs]

a 532 diode

CLICKERS-CLACKERS

[mixedgas]

Well, you can have the diode drive a resonant ring cavity to build up power. The doubler sets inside the ring. Then you have a piezo to move one of the ring mirrors back and forth to keep the ring resonant with the diode wavelength, and also have to temperature tune the doubler.. A bit nasty in the cost of coatings and complexity and needs a very brainy controller. Mainly done at 404 nm, because, 808 has power. Which is not so useful.

Steve

[absolom7691]

CLICKERS-CLACKERS

Hmmm, this looks VEEEEEEEEEEERY interesing!

Steve, sounds like a lot more trouble than it is worth! Single line AO mods are pretty inexpensive, no? I am thinking of messing around with this, but if it is more than a $100 or so, I don't think I will bother.

[Stoney3K]

Hmmm, this looks VEEEEEEEEEEERY interesing!

Steve, sounds like a lot more trouble than it is worth! Single line AO mods are pretty inexpensive, no? I am thinking of messing around with this, but if it is more than a $100 or so, I don't think I will bother.

You can also blank and modulate the green with a spare galvo. It doesn't need to be as fast or have a huge scan angle as your main scanners, just bounce (part of) the beam away into a beam dump just like an AOM does.

Should be a tad cheaper and easier to get. $100 will get you 2 galvos and matching drivers, so you can blank 532 along with something else (like, 473/457 or a gas head).