Just wonderingif possible 808-404nm

If green lasers are made by going 808 to 1064 to finally 532nm using crystals and blue lasers made the same way by crystals WHY NOT VIOLET? Can someone use crystals to change an 808nm wavelength into 404nm violet because it sure seems that 808nm are cheap and powerful! If this can be done then what "crystal" would be needed to do the job...one like the blues and greens use to go from a higher nm to a lower nm by half like 1064nm to a 532nm ect...

Finding the right material (crystal) is exactly the problem.... however, the research direction is more in replacing the complex, expensive and finicky DPSS setup by something that lases directly in the desired wavelength.

Possible, but very difficult, and expensive. Directly-doubling a diode is tricky, it's much easier to double the nice, clean output of the doped Nd:YAG than to directly-double a diode.

And especially with how cheap and easy 405nm is, doubling 808 to 404 is a far too expensive and tricky a proposition to be worth it. But like dr-ebert said, current research, hopefully, is making some of these tedious methods obsolete. DPSS will never be completely obsolete, but doing crazy stuff just to get a specific color of blue or violet is becoming obsolete.

bibo (BiB3O6)

quadcam said:

bibo (BiB3O6)

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In theory yes, in practice -- not really.

The problem with edge-emitting diodes (like all of ours are) is that they have really shitty beam specs.

In order to frequency double, one needs to have a very very good beam quality and a crystal capable of phase matching at the given wavelength.

VCSEL are freakin' awesome because you get a high quality beam out of a diode laser, but these are not common and expensive.

With a TON of power (like 5W 808) and a KNBO3 crystal at the right temperature, you might get a couple mW of 404nm with an edge emitting diode laser as the pump.


I have a 488nm laser which is a directly doubled diode. It uses a 976nm VCSEL diode and an intracavity NLO crystal with an output coupler. It is pretty neat.

GooeyGus said:

In theory yes, in practice -- not really.

The problem with edge-emitting diodes (like all of ours are) is that they have really shitty beam specs.

In order to frequency double, one needs to have a very very good beam quality and a crystal capable of phase matching at the given wavelength.

VCSEL are freakin' awesome because you get a high quality beam out of a diode laser, but these are not common and expensive.

With a TON of power (like 5W 808) and a KNBO3 crystal at the right temperature, you might get a couple mW of 404nm with an edge emitting diode laser as the pump.


I have a 488nm laser which is a directly doubled diode. It uses a 976nm VCSEL diode and an intracavity NLO crystal with an output coupler. It is pretty neat.

Click to expand...

Pics please? :san:

OK, for a physics lab experiment and horrible for the DIY laser hobby! :-/

But thanks for the info!

With a TON of power (like 5W 808) and a KNBO3 crystal at the right temperature, you might get a couple mW of 404nm with an edge emitting diode laser as the pump.

Click to expand...

BBO crystals do it near room temperature, BUT you need a 3W +FAC, or ECDL to do it. It is easily bested by an x-box diode though..