Laser-induced fluorescent laser?

Wondering if a Laser-induced fluorescence laser exists?

It'd work a bit like the frequency doubling DPSS lasers except that coherent fluorescent light would be emitted.

405 nm lasers seem like they'd be the perfect candidate to cause a crystalline substance to fluoresce and have the fluorescent light be coherent.

Anyone ever heard of such a thing?

If it were indeed possible one would think that a rainbow of laser light colors could be produced based upon impurities introduced into the fluorescing crystal.
That would sooo rock!

-Scott

Yes, that's how all 532nm green DPSS lasers are made, in addition to many others lasers.

For green, 808nm diode pumps Nd:YAG or Nd:YVO4, which fluoresces and lases at 1064nm, for subsequent frequency doubling to 532nm.

I was reminded of dye lasers when I read the first bit, until I saw the solid state part.

You'd need to find materials that fluoresced efficiently, because when i point my 405nm at a white piece of paper it makes the dot appear 473nm-ish, but the light does not go through the paper...

pullbangdead said:

Yes, that's how all 532nm green DPSS lasers are made, in addition to many others lasers.

For green, 808nm diode pumps Nd:YAG or Nd:YVO4, which fluoresces and lases at 1064nm, for subsequent frequency doubling to 532nm.

Click to expand...

I appreciate what you are saying but:

Frequency upconversion in KDP (like what is going on inside a typical DPSS laser pointer to make green light from the infrared laser running inside the thing) is usually not called fluorescence.

Fluorescence generally refers to single-photon effects (response linear in intensity) like shining UV light on dayglo inks, etc. Frequency doubling in KDP is a two-photon effect (response nonlinear in intensity).

Essentially what I am wondering is if solid state lasers exist that work in an opposite fashion as your typical KDP combination, meaning, the high frequency pump laser produces a laser of a frequency lower on the spectrum?

-Scott

I know.

Yes, the KTP converts 1064 into 532 through second harmonic generation, I agree. I wasn't referring to that.

I was referring to the step before that, where the 1064nm light is created using fluorescence of a Nd:YAG or Nd:YVO4 crystal, excited by an 808nm laser (typically 808nm, at least).

2 crystals, 2 steps. First is optical pumping of a fluorescent material by a higher frequency laser; then the second step is second harmonic generation in a non-linear crystal.

BOTH effects happen in a 532nm laser, 808 -> 1064 -> 532.

pullbangdead said:

I know.

Yes, the KTP converts 1064 into 532 through second harmonic generation, I agree. I wasn't referring to that.

I was referring to the step before that, where the 1064nm light is created using fluorescence of a Nd:YAG or Nd:YVO4 crystal, excited by an 808nm laser.

2 crystals, 2 steps. First is optical pumping of a fluorescent material by a higher frequency laser, the second is second harmonic generation in a non-linear crystal.

BOTH effects happen in a 532nm laser, 808 -> 1064 -> 532.

Click to expand...

You've done your homework.

pullbangdead said:

I was referring to the step before that, where the 1064nm light is created using fluorescence of a Nd:YAG or Nd:YVO4 crystal, excited by an 808nm laser (typically 808nm, at least).
.

Click to expand...

Ah yes, now that I'm paying attention! Apologies!

So that means that there likely exists (or can exist) an equivalent crystal
to do the same with 405 nm.

Until recently 405 nm hasn't been a common wavelength for your average laser hobbyist. It inclines me to think that something like this is being worked on if it hasn't already been developed.
That would mean that at some point in the not too distant future it may be possible to economically have virtually any color laser pointer (if the DPSS green revolution is any indicator).

Hmmm.

Thanks for your responses!

-Scott

DPSS green revolution? The technology behind DPSS 532nm has been around for decades even if it hasn't really been very mainstream until maybe about a decade ago.

I think he was calling them going mainstream the 'revolution'.

Ah. Well, considering they've been available on the consumer level for a good decade now, I still wouldn't call them a revolution heh. Now the new high power GaN diodes on the other hand. I think that classifies.

qumefox said:

Ah. Well, considering they've been available on the consumer level for a good decade now, I still wouldn't call them a revolution heh. Now the new high power GaN diodes on the other hand. I think that classifies.

Click to expand...

Just a few years ago $100 for a 5mW green was a good deal, if you could find it. Now they practically give 5mW ones away with cereal, and everybody and his uncle Bob has one at 100mW+. There might not have been a revolution in technology, but certainly there has been in accessibility.

Netscott said:

Ah yes, now that I'm paying attention! Apologies!

So that means that there likely exists (or can exist) an equivalent crystal
to do the same with 405 nm.

Until recently 405 nm hasn't been a common wavelength for your average laser hobbyist. It inclines me to think that something like this is being worked on if it hasn't already been developed.
That would mean that at some point in the not too distant future it may be possible to economically have virtually any color laser pointer (if the DPSS green revolution is any indicator).

Hmmm.

Thanks for your responses!

-Scott

Click to expand...

I do know that 430nm (blue) lasers can be created from frequency tripling the 808-->1064 (similar to the frequency doubling in 532nm lasers) but that it is insanely expensive. Search Sam's FAQ if you're more interested... I think it was in the section about various colors of lasers.

EDIT: 355nm light comes from the frequency tripling of 808-->1064, not 430nm. Reference: http://www.rp-photonics.com/frequency_tripling.html
While 430nm is possible via DPSS, it is through another method. I suspect it is through some sort of frequency doubling/tripling coupled with sum and difference frequency generation (http://www.rp-photonics.com/sum_and_difference_frequency_generation.html)
See my post just below for a link to a 430nm DPSS laser.



While having virtually any color laser pointer at an economical cost may be in the future, I don't think it will be through DPSS. DPSS tends to be quite tedious and expensive due to the complex nature of the various compounds/crystals and the alignment needed. In addition, efficiency isn't as good in DPSS systems as the average diode. For the future of new colors in lasers... I would bet on new diodes - like the 405 blu-ray and the 445

But either way they do it, I can't wait to see where lasers will be in 10 or 20 years!

-Alex

Never heard of 430. I know you can get 404 by directly doubling 808. 457 and 473 come from doubling the weaker lines off of a doped ND crystal just like 532, only the cavity is coated for 914 or 946, instead of 1064, and it's very temperature dependent.

I can't find it on Sam's FAQ anymore... maybe I found it somewhere else. But here's where you can buy 430 DPSS lasers if you so desire (and to prove that they do exist): Shanghai Dream Lasers Technology - DPSS Green, Blue & Red Lasers, Precision Optics and Crystals

And see my edit above.

I can make my tile floor fluoresce with a 405nm laser. I couldn't think of a way to photograph it without the camera just capturing the laser itself, then I realized I could simply put the end of the host directly on the floor and you don't see the laser at all, just the effects. I'll post some photos a little later, once then sun goes down.