Mega RGB via KTP / Dye / 445... Discuss...

[dsli_jon]

....OK, out of respect to Sir Pelosh, there, I've decided that I and this topic should 'get its own room'...

Discuss...

Hey k4q -

I take it you do not mix the blue BEFORE the dye system....eg 1x KTP pumping dye to 630nm (R) plus 1xKTP 532nm (G) plus 10W 445nm (B) plus Dichros=RGB system

Umm, not sure, as this is a purely 'concept system', at this point... no time to build-up my own 10-20W Blue, and no extra 'cheddar' to buy an off the shelf, one, like this threads' fine example... But, ideally, you would only need one KTP, pumping ~25-30W direct-into the dye-head... assuming good-fresh dye, and a direct (non-fiber coupled) pump-arrangement, you'd likely be able to get ~12-14 Watts, tops, of 630 for your Red... then, assuming you had a *really* hot KTP (which I do...) you could still-have
10+W of 532, to combine-in, with the R and B...

Granted, the beam-profiles would be prolly hard to 'mesh', and both the Red and Green would be pulsed, so, not sure how seeing those 'dashes' in-with the CW Blue would-look, say in a cone, or sine-wave... ?? dunno... but the idea of close to 50W of RGB - for LESS than $1 MILLION DOLLARS (prolly what that 66W Arctos costs...) is mighty-intriguing...

Dear Santa....

peace...
j

[dsli_jon]

Hey cat...

I think you may have trouble getting 10-12w of 630nm from a dye by pumping with 10w of green however much unfocusable blue you mix in. ... Do you have some secret dye which can turn 455 into 630 ??????

No, I think you mis-understood me... I was referring to a set-up, where you would 'pick-off' ~30-35 Watts of 532 in a KTP-system (ie: the one we currently have in-shop, does
~ 48W, after the steering prism / mir (so, not much IR in the readings) and use *that* to pump the dye, to give you the 10+ Watts of 'Red'...

(...Also, something I should clarify, it's not just 630nm...really, in that '10-12+ Watts of "Red" are actually several-lines, ~629nm > 650nm, thus yielding a total-power of 10+ W... Still, the 'majority' of the power in the beam is, ~630nm.... it's a really bright, beautiful Red....

I can't see any-amount of 445, alone, ever getting R6G to-lase much, if at-all, even-if you 'Q-Switched it'... ie: I can pump the same dye-cell, with 18W of CW 532, and it will just not lase... it really needs the 'high-peaks' of Q-Switching, to 'kick-start' the pop. inversion, with only the 532... and clearly, the 'absorption-efficiency' of 445 in dye is much, much lower, still, so not even sure Q-Sw'd 445 would work...

Granted, in an Argon-pump situation (...more Blues than Greens) even with only ~8-9 Watts of CW multiline Argon, you can get R6G to-lase...but in that-case, it's more a factor of the particular dye-mix and the specific-lines in Argon, perfectly-matched to the dye for max absorption-efficiency... IIRC... I think it would be *awesome* to see what you could get with 30-40 Watts of CW Argon from a properly-matched dye-head... OMG, what would 25 Watts of 630 look like??!!

Recently, we produced about 10W of Red, pumping only ~32W of Green into a dye-head, but via a fiber-pump and, like 6 yr-old dye... so, a direct, 'on-deck' arrangement, with fresh-dye, would undoubtedly yield better efficiency (though, you'd have to be more 'careful' when aligning such a system, not to burn the window of your dye cell....focal-point is more critical with that much power...

So, say you had ~46 W of Green, pick-off ~35W of Green, as-pump, should easily give you ~12+ W of Red (again, with an on-deck pump / fresh-dye...) and then, combine the 10+W of Green w/ yer 10+ of Blue (prolly best to use a 12W head, min or a 20W, turned-down a bit) and then post-dye head-combine all, to 'white'... It'd be a *fuuuuUn* project, to be sure....

Martin - sure I can't talk ya into 'trading' this Purelight Ion WL for a 10W Blue? I'll even pay fer shipping the WL to ya...

Oh well, one can 'dream' right?
cheers...
j

[dsli_jon]

hey k4q....

I gathered 40-50W's of 532 would be something stupid to mix with 10W's red lol....

..Uh, well, you might have missed that in the 'concept rig' above, you would not actually *have* 40-50W of 'useable' Green, any-longer, since ~30-35W+ of it would be picked-off to *produce* the 10W+ of Red... it effectively gets 'lost' in that process...

You'd (ideally) end-up with ~10-12W of Green, to mix w/ the ~12-14W (best-case) of Red and ~20W of Blue, all-before optics-losses, etc...

And sure, you could potentially use one of the 'high-power module' KTPs (~60W max-potential), but don't think more green would really be helpful in this already 'not-perfectly-ideal' color-mix...

Yeah, perhaps with a true 60W of Green (hypothetically) you could pump the dye with ~40W, and yield 15-16W of Red (???) leaving ~15W of Green to mix-back with the Red and 20W of Blue... but, you have to remember, there are 'sticker-watts' and 'real-world watts', and that can be 'quite a gap', sometimes...

lovely thing about such high power is to throw some here or there were you need it and then just adjust the current settings to suit yourself or setup.l

Indeed.. that's why people still go thru the effort to mod them and/or lug them around... Cap'n Pat (Laserman532) was oh-so-Right, when he rationalized 'starting it all', way back when... there ain't nothin much else that delivers so-much 'beam for the buck'... not as 'purdy', granted, but a heck of a lot 'easier' to lug around than an I-400!

peace...
j

[dsli_jon]

hey k4q -

...but nothing can beat the look of pure science and perfection at its best.

I agree!

You could also setup the output beam on a PCAOM to match the pulse rate of the KTP so the blanking appears the same on all colours?

Mmmmyeah, not really. Most-power you could realistically expect to pump thru a PCAOM might be 20W, and-that, only-with a 'specially-grown' x-tal, from NEOS, and-that, with a 'large clear-aperture', for the larger beam... otherwise, you'd have burns in the face, right-quick... and that would be one boku-bux x-tal (prolly ~$6-7K or more!)

...You *might* be able to try large-aperture / high-power AOMs, for each color-line, but I'd venture to say, you'd end-up wanting to claw your eyes-out, trying to get the modulation to 'allow' smooth-blanking vs the q-sw pulses... And, once-out to the galvos, not sure if you'd end-up with some 'interference', anyway...

IMHO, the best-approach for such a system would-be a high-speed 8-ch. color-box (dichros), and retro-style blanking, since you're most-likely not gonna have good-enough 'convergence' with such disparate beam-characteristics from these 3 sources, to really go for decent-graphics, anyway... it really would be only ideal for outdoor aerial shows, IMO, so, in such a case, I don't see it would be really worth the extra cost for such AOMs... and if you burnt an x-tal face??? ...Dichros, by comparison, are cheap...

So, tell ya what - you 'bankroll it' and I'll build it, whatd'ya say? I promise it will be a 'world-class' rig...



...and I'd for-sure retro-fit with a nice 10-pos'n. table, up-top, with all color-control and blanking under the top-deck... it'd be the 'talk of the town', fer sure...

cheers...
j

[mixedgas]

Jon, PM me off list about the 40 watt pcaom trick.
Its cheaper/easier then you think.

The reason the Scope-KTP dye will not run CW is triplet state quenching, the Laserscope dye design does not flow the dye fast enough for CW, but KTP in CW would pump a classic jet dye. There is a major difference operating parameters in in cell dye vs jet dye vs flash lamp pumped dye.

Will 445 ever pump bulk dye?, No, most likely not with current 445 nm Diodes.

1359/3 = 464 blue.. 1371/3 = 457 nm blue.

Steve

[dsli_jon]

Hey P'fessor -

Jon, PM me off list about the 40 watt pcaom trick.
Its cheaper/easier then you think.

I just love learning... Incommmiiiinngg!

The reason the Scope-KTP dye will not run CW is triplet state quenching, the Laserscope dye design does not flow the dye fast enough for CW, but KTP in CW would pump a classic jet dye. There is a major difference operating parameters in cell dye vs jet dye vs flash lamp pumped dye.

Ah yes, thus-why an Argon-Dye sys's efficiency is much better than the 532s, likely, the combo of 488 and 476 lines being near-perfect 'matches' to R6G's absorption-curve and the dye-jet used in the Cohr-heads, vs the cell-style in the LS 600s...makes perfect sense...

Type to ya soon...
j

[flecom]

problem is as much as a q-switched scope scares the crap out of me the idea of then adding toxic chemicals at high speeds makes me want to run away lol

the dye modules are really tempting though.... I really love red... but too big/bulky to be of any real use to me

and as far as $$$ goes, laser scopes are pretty much worthless, as is 445... only expensive bits would be all the galvos if you use galvo blanking if not galvos and PCAOM's

no idea what a dye module goes for

but realistically you could probably put this thing together pretty inexpensively actually

[goninanbl00d]

Jon, PM me off list about the 40 watt pcaom trick.
Its cheaper/easier then you think.

The reason the Scope-KTP dye will not run CW is triplet state quenching, the Laserscope dye design does not flow the dye fast enough for CW, but KTP in CW would pump a classic jet dye. There is a major difference operating parameters in in cell dye vs jet dye vs flash lamp pumped dye.

Will 445 ever pump bulk dye?, No, most likely not with current 445 nm Diodes.

1359/3 = 464 blue.. 1371/3 = 457 nm blue.

Steve

Ahh, so that's why the Laserscope cells don't run CW. From what I've read it's near-impossible to get a CW dye laser using a cell/cuvette- a dye jet is needed.

Also, if I remember correctly, Rhodamine B (not 6G) is used in the Laserscope dye cell.

Both dyes, however, have near 0 absorption at 445nm. So using 445 as a cheap pump doesn't work.



http://omlc.ogi.edu/spectra/Photoche...odamine6G.html

[Stoney3K]

Both dyes, however, have near 0 absorption at 445nm. So using 445 as a cheap pump doesn't work.

http://omlc.ogi.edu/spectra/Photoche...odamine6G.html

That's because it was not designed for it, right? The absorption spike at 532 is quite a dead giveaway.

You could also pump it with 532nm DPSS, but I fail to see a good point in that when diode red is just as cheap.

Are there any dyes that *do* take 445nm wavelengths and produce something usable?

[mixedgas]

See for yourself,

www.exciton.com

The real question is how are you going to get 445 excitation to have either the tiny spot size, or the peak power.

Perhaps less then or equal to 100 micron spot size in a flowing jet?

Steve