Rhodamine 6g & 532nm

[GooeyGus]

What do you think of this?

http://cgi.ebay.com/Coherent-Dye-Rin...3286.m20.l1116

I'd still need the circulator, right?

Also, will this work as laser dye or does it need to be a special compound?

http://cgi.ebay.com/Coumarin-99-100g...3286.m20.l1116

If you cant tell, I'm really new to this dye stuff

[Laserman532]

What do you think of this?

http://cgi.ebay.com/Coherent-Dye-Rin...3286.m20.l1116

I'd still need the circulator, right?

Also, will this work as laser dye or does it need to be a special compound?

http://cgi.ebay.com/Coumarin-99-100g...3286.m20.l1116

If you cant tell, I'm really new to this dye stuff

yes and no laser says may be incomplete, if there are no mirrors or nozzel you are hosed. NOT cumeron or whatever. always start with r6g you must make sure that the optics are set up for the wavelength you will operate at. The lasers came with sets of optics for the dye ranges you want to work with. if you pump with an argon and that is all yo have get a dyd laser set up for R6G or R110 (redder) 245 dollars is a steal even if you wreak it out for parts to build a wind chime. the invar rod is AWESOME and will make a lovely wind chime. yes yo still need a circulator. lets chat dye lasers at pacolem, i can enlighten you a bit.

[Laser Ben]

So just how dangerous is this dye? I have been looking at pumping dyes with a LED to create a Dye laser, but the hazards of the dye have been scaring me off a bit. Is it dangerous if it comes into contact with skin? Or does it have to be ingested? What kind of power levels are required to get a small dye setup to lase. Can it be done with 5 watts of blue 435nm light?

[tocket]

In my opinion, as an organic chemist working with dye design and synthesis, R6G is not particularly dangerous. Depending on the solvent, it might be able to penetrate your skin and then the situation might be different. I suspect that any such toxicity is due to photosensitization, so if you manage to get R6G in DMSO on your skin you just have to avoid exposing that area to light until the R6G has left your system (should be within a week) to avoid damage.

Even if the dyes you're working with are not toxic themselves, I would still advise you to use gloves. This is simply because the dyes can typically stain your skin for quite some time, and it might not be so much fun to walk around with green hands for days. As an example I managed to color my left hand blue for a whole week after a large scale experiment with methylene blue.

Other rhodamine dyes might not be equally harmless though, but if you want my opinion on any other dye, just ask.

As for R6G, I would not hesitate to consume a fairly large quantity of it, as long as it's food or medical grade... and I'm only a little bit crazy.

[lls@laservideo.com]

I have several Coherent 599 dye lasers if anyone is interested. I used them with my laser video projectors from 1991 until 2000. They were pumped with 488 and 514 from 2 polarization combined argon lasers to produce 620nm red. The pump sources were 2 Coherent 310 argon lasers. Total output of red was 4 watts. The red can be tuned with the BRF from Gold to deeper red. Max output was near 620nm. The Coherent 599 is more stabel and higher efficiency than the SP dye laser. The Coherent dye nozzle was the best. It produces a dog-bone stream that provides a flat sheet in the center of the stream. The 476 and below form the argon lasers were combined for the blue beam.

Maximum output is only obtained with a triplet quencher - generally COT. It has a very pungent odor that does not decay for years, but will increate output by about 30%.

I am sure that I have the MSDS on R6G and COT in a file somewhere.

I used the Coherent 599 head but built my own circulator. Also added a stepper motor to the splash guard. The circulator was processor controlled close the splash guard, bring the pump up to pressure, switch the pump to the jet and then open the splash guard. I also added TE coolers for the dye under processor control and a water cooled beam block.

Since the fluid is under high pressure and is sensitive to temperature, spraying and leaks can be a problem. This is not a project for a novice.

With 2: 10 watt argon lasers, a dye laser and 3 AOMs, I was able to produce 4 watts of pure white raster after the modulators and scanners - horizontal scanner was a Ferranti or Speedring polygon scanner and vertical scanner was a General Scanning G120PD.

There's a description of the laser video at www.laservideo.com

[Laserman532]

I have several Coherent 599 dye lasers if anyone is interested. I used them with my laser video projectors from 1991 until 2000. They were pumped with 488 and 514 from 2 polarization combined argon lasers to produce 620nm red. The pump sources were 2 Coherent 310 argon lasers. Total output of red was 4 watts. The red can be tuned with the BRF from Gold to deeper red. Max output was near 620nm. The Coherent 599 is more stabel and higher efficiency than the SP dye laser. The Coherent dye nozzle was the best. It produces a dog-bone stream that provides a flat sheet in the center of the stream. The 476 and below form the argon lasers were combined for the blue beam.

Maximum output is only obtained with a triplet quencher - generally COT. It has a very pungent odor that does not decay for years, but will increate output by about 30%.

I am sure that I have the MSDS on R6G and COT in a file somewhere.

I used the Coherent 599 head but built my own circulator. Also added a stepper motor to the splash guard. The circulator was processor controlled close the splash guard, bring the pump up to pressure, switch the pump to the jet and then open the splash guard. I also added TE coolers for the dye under processor control and a water cooled beam block.

Since the fluid is under high pressure and is sensitive to temperature, spraying and leaks can be a problem. This is not a project for a novice.

With 2: 10 watt argon lasers, a dye laser and 3 AOMs, I was able to produce 4 watts of pure white raster after the modulators and scanners - horizontal scanner was a Ferranti or Speedring polygon scanner and vertical scanner was a General Scanning G120PD.

There's a description of the laser video at www.laservideo.com

hey paul, pat b here...thanks for joining the forum. It is a great group of people with talent, look forward to your contributions!

[lls@laservideo.com]

Thanks Pat.

I'm also building some 1 -1 1/2w solid state RGB conventional laser projectors. haven't updated my site for quite a few years - need to find the time.

Been around looking for a while, but this was my first post.

BTW, at the bottom of the Laser video description page @ laservideo.com there is picture of a SP171 argon pumping a 599 dye laser. The 599 cover is off and you can also see the Blue and Green beams. This pic is of a laservideo projector optical bed.

Paul

[shrad]

hi Paul!

your system is totally AWESOME! the colours you achieve are truly MINDBLOWING and so are the contrasts

the picture of the dye chamber pumped by the argons is also really appealing

could you please post some more pictures of the setup, if it is possible? I could have the possibility to scavenge a dye laser from spectra-physics with optics, pump, and every component... so this is really interesting for me

[jonsinger]

I came to this thread a bit late, and the discussion may be over; if not, however, I hope I have some things to contribute.

First, in response to @Starlogic's original query:

1) Rhodamine 6G does not seem to change much in storage. My current stash is probably 30 years old, and was intended for use as a biological stain; it lases just fine with flashlamp pumping, and I have managed to pump it with a TEA air laser, though it wasn't easy.

2) Just about _any_ dye that doesn't come from a laser dye company (or from @tocket's lab) is very unlikely to be particularly pure. The impurities in it will almost certainly increase the threshold, but if it's a decent dye they won't usually prevent the stuff from lasing, even CW, provided you pump it hard enough. (If you are really concerned, you can build a chromatography column and teach yourself to use it. It should also be possible to purify dyes by recrystallization, but you may lose more that way. I suspect that @tocket knows considerably more about dye purification than I do, and may be able to provide some better wisdom here.)

3) As far as I am aware, the record minimum pump power for a CW dye laser running R6G was about 69 mW from a green DPSSL. Remember, though, that's a record, and I'm sure the dye was righteous "laser quality" stuff. It apparently isn't easy to run a CW dye laser with pump power of less than a Watt or two under ordinary circumstances.

3A) That said, however, the record low for any CW dye laser, as far as I'm aware, was set in 1986 by some people who managed to pump a chilled solution of Oxazine 1 Perchlorate with 10 mW from a HeNe (!). I just got my hands on a copy of their article yesterday, and it's pretty interesting.

4) It is possible to run a flashlamp-pumped dye laser with minimal mirrors, but only if you _really_ know what you're doing. Under ordinary circumstances, as @MixedGas says, they want mirrors.

4A) Most people who pump dyes with nitrogen lasers and think they are running their dyes without mirrors are wrong. The walls of their dye cell are serving as mirrors. Here's what the output of a nitrogen-pumped dye laser looks like when there aren't any mirrors at all:

http://www.jossresearch.org/pictures...ofocus.c17.jpg

(The liine is curved because the paper viewing screen was curved.) Notice, no bright spots. If you want to verify this for yourself, build a cuvette that is carefully misaligned so that the windows are at the wrong angle to function as mirrors. You will find that it has higher threshold, and you will find that the output is really diffuse.

5) @GooeyGus asks whether laundry detergents work. Not all of them, of course; but quite a few will lase fairly nicely if you pump them with a nitrogen laser. (@MixedGas is just wrong about detergents being a dye's worst enemy, btw. In fact, many of the early CW dye lasers used Ammonyx LO detergent as an additive. It even showed some signs of being a mild triplet quencher.)

5A) If you want something better than laundry detergent, however, I will suggest "Optic Whitener ST" from www.dharmatrading.com -- it is a very fine blue/indigo/violet laser dye, dissolves nicely in rubbing alcohol from the drugstore, and works with both nitrogen pumping and flashlamp pumping. I have no clue whether it would work in a CW dye laser, and unless someone comes up with a good strong UV pump source, I probably won't find out any time soon. Both Jarrod Kinsey and I can also commend the stuff that's inside a Sharpie "Accent" highlighter marker.

I cover these and some other inexpensive/available things you can use as laser dyes on one of my pages --

http://www.jossresearch.org/tjiirrs/010.html

-------------------------------
About nitrogen lasers:

6) Although it is true that O2 tends to cause arcs and sparks, it is definitely possible to run an air laser. They don't require extremely flat electrodes (though smoothness does help minimize the sparking issue), you don't need to mess with vacuum pumps and leaks and sealing, and after you build a few TEA machines you'll be able to throw one together in an hour or two. A TEA nitrogen/air laser is absolutely the easiest laser to build. Period.

If anybody cares, here's a bit of a tutorial --

http://www.jossresearch.org/lasers/n...tea-laser.html

@GooeyGus asks whether a HeNe power supply will work. It probably would, but I wouldn't go that route because the HeNe supply doesn't want to ramp up to trigger level many times a minute, and may crap out if you make it do so for an extended period. I like to use the power supplies out of old electronic air cleaners, which I get for a few bucks at thrift stores. You may have to look for a while before you find one, but it's easier and cheaper than messing with NSTs.

7) Jarrod Kinsey, the guy with the YouTube video that @MixedGas linked to ( I don't remember whether he's using Coumarin 1 or 4-MU in the video; I think I sent him small samples of both) is a truly excellent builder of room pressure air/nitrogen lasers, and I can assure you that he knows about putting mirrors on things & getting more power. The reason why he doesn't have a mirror on the laser in the video is that he has adjusted it so that essentially all of the output comes from one end. He does almost all of his that way. I do a lot of mine like that as well, but on my most recent one I noticed that it was easier to adjust if I let beams come out of both ends, so I ended up putting a mirror on it. Even though the channel was rather long for a TEA nitrogen laser, I got a definite improvement in the output when I got the mirror aligned right. Here's a page about it:

http://www.jossresearch.org/lasers/n...tea-laser.html

8) There is a trick to using 4-MU, which is that you need to add a small amount of ammonia or lye or KOH (or possibly a weaker base, for example washing soda, though I haven't tried that yet) to the dye solution, unless your pump source is extremely powerful. (It is possible to lase 4-MU in neutral or acid solution, but it isn't easy. As far as I know, though, 4-MU in acid solution has the widest tuning range of any laser dye. If anybody has found a dye with a wider range, I haven't encountered it.)

-----------------------------
Another item:

9) Earlier in this thread, @Laser Ben said something about pumping a dye laser with a LED. That, alas, is not gonna happen. If you don't believe me, think about how much energy has to go into a flashlamp in order to run a dye laser for maybe a quarter of a millionth of a second; the best I've ever managed is 6 Joules. Then think about what would happen if you put that much energy into your LED in that amount of time. (If you want a hint, 6 J in 1/4 of a usec is roughly 24 million Watts, ...and that's rather low.)

9A) The pump beam for a jet dye laser has to be focused down to a spot that is roughly 25 microns across. That's 1/40 of a millimeter. If we figure that the pump power is 2 Watts, the resulting power density is a little over 100 kW per square centimeter, unless I've miscalculated it. If you can focus the output of a 1-Watt (or higher power) LED tightly enough to get at least close to 100 kW per square cm, you have a chance of being able to run a CW dye laser with it. Otherwise, it isn't likely.

Cheers --
jon

[andyf97]

@johnsinger, That's got to be one of the best replies in history, very in depth and informative. I touched Rhodamine 6G about 15 years ago for this job but ended up giving it up as a bad effort oh and Welcome to PhotonLexicon.

Andy