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FrozenGate by Avery

1W 473nm for $253.56






Of course. And if you solder a second pot onto the driver, you'll be able to adjust the wavelength too. KipKay told me.
 
Of course. And if you solder a second pot onto the driver, you'll be able to adjust the wavelength too. KipKay told me.

I heard about that guy...good at what he does:whistle:
 
awesome! now that we got kip kay in here I can finally ask my question!!! on youtube he told me if i pooped in the toilet, threw a couple wires in their, I could pot mod it into a burning laser!!! i just don't know where to put that damn positive wire
 
Use a second pot you say? Hmm. That could work. Is it better to use a cast iron or aluminum clad one?








*runs*

this post brought to you by an annoying case of insomnia.
 
Playing devil's advocate here -

No objection to your position on these not being up to spec. Of course no objection to that ;) But why the theoretical objection to hosts that could handle a 5W IR diode?

On the flashlight side of things, those P7, XM-L, SST-50 etc LEDs take on like 3A at 4V (roughly?), so we're looking at ~12W in one host.

Why no dice for a laser? (in theory of course - no objection here - these Chinese listings AREN'T IT)

Put it this way- yes, they have a very high TDP, and like you said, up to 12W of heat energy to be dissipated.

Now, in those hosts, the main priority is getting the heat out of the LED, and keeping it below it's operating temperature ceiling, which, for the P7, happens to be 85C. Now, as long as the LED stays below that maximum operating temperature (we're looking at a realistic margin of around 60-70C here), it's happy. You just want light out.

In most cases the LEDs operate around 50C or so, with a host temperature of 40C or thereabouts. I'm not a flashlight geek, that's csshih's job to give you exact numbers. I'm just going off numbers I've gotten from similar heat loads with similar styled heatsinks. Anyway, I digress.

And in all of these cases, the LED requires no thermal stabilisation beyond 'keep it below X temperature'. That's it, that's all it needs. And within that temperature range, it's happy. Just feed it electrons, and it gives you photons in return, and heat.

Now, with a DPSS laser, we know two things.

  1. The diode will need temperature stabilisation
  2. The Nd:YVO4 will be better off with temp. stabilisation
  3. The KTP will also need temperature stabilisation

How many of the above does a torch provide? None.

First point- the diode needs temperature stabilisation. Without it, the diode's wavelength will fluctuate as much as 3 or so nm going from 20 to 60C, not to mention most diodes don't even have an operating temperature ceiling that high.

Now, with an LED, a 2-3nm shift wouldn't be noticeable. But when it's used to pump a gain medium, even a 0.1nm shift will be noticeable in terms of power output. That's why just about every labby out there has some form of temperature stabilisation- if you want it to be even remotely stable in operation, temperature regulation is a MUST.

The world's most powerful handheld green, the Hercules (by Laserglow and CNI), uses a fan in conjunction with a TEC element inside to keep the diode within operating spec, and that only has a peak of 800mW.

Even though Nd:YVO4 has a very large absorption spectra (compared to Nd:YAG, for example), wavelength changes WILL be felt in terms of power output. I don't have any graphs on me at the moment, however, someone around here does (Cyparagon? wannaburn?), and the effect is clearly noticeable when you're using a bodgy pump diode.

Second point- the KTP and YVO4 are also temperature sensitive, however, the KTP is more sensitive than the YVO4. In many of the labbies on the market, the YVO4 shares a TEC with the pump diode, and the YVO4's happy with that. It doesn't need much in the way of stabilisation, but what it does need is some form of cooling, so that the thermal shock that results from having watts of power ass-rammed into it at any given time doesn't crack or distort it, both of which will lead to catastrophic (as in, O LOOK TEMwtf!@:D!) failure of the laser.

Third point- same goes for the KTP, except it's more prone to damage. With intracavity doubling, the intracavity power will be higher than the pump power, or the output power. It's a resonant cavity- not all power will get converted to 532nm and make it out. If it were a straight-through superradiant 'laser', the intracavity power (and power through the KTP) will be significantly lower than the pump power. However, in a resonant cavity, with a 95% reflective OC, even a 5mW green pointer will have many watts of power circulating around. You can imagine the deal with a 5W pump.

Now, the problem is, KTP doesn't like high power densities very well, it suffers from grey tracking, as well as generally falling apart from stress fractures. But unlike the pump diode, KTP prefers to be heated, often to 0.1 of a degree for optimal efficiency. That degree of precision isn't necessary in a handheld, however, some form of temperature regulation is needed.

There's also a fourth point about dichroic coatings of the OC and HR shifting with temperature, but the wide linewidth of Nd:YVO4 more than makes up for that. Or, as this know-it-all-and-is-always-right member of Photonlexicon would point out, it'll turn into a multiline argon. Turn up the current, and you get more lines! Yay! And I quote "457nm, 473nm, SHG, SFG and SFG of SHG, and SHG of SFG". Now, ignoring the fact that KTP doesn't even double below 500nm because it can't be phase-matched (well, there's ppKTP, but that can only be matched to a single wavelength, meaning it only works at that wavelength, definitely ruling that theory out). Also ignoring the fact that if 946, 1342 and 1319 could be superradiant in a cavity tuned for 1064 only (and provide enough power to induce SHG in a crystal that can't even double blue, well, we wouldn't have such crap efficiency with those wavelengths, now, would we? Not to mention that if KTP could double below 500nm, nobody would bother with LBO, as it's a PITA to work with. Oh, and when I pointed that out, I got kickbanned from their IRC by said member. So, a member's unverified, unconfirmed results, (apparently nanowatts of 473 were detected), taken using an unknown laser, on an unknown instrument, is now more valid and reliable than a source that has been published many, many times, as well as being peer-and-publisher reviewed (namely RP-Photonics and Solid State Laser Engineering). Any attempt to question the inherently questionable nature of the observation, which just so happens to go against just about everything published on the topic, will earn you a kickban.

And you wonder why PL members have a bad name. You know what they say, it's the few that make everyone look bad. :yabbmad:

End rant. I'm having a bad day, and this is vaguely relevant.

The bottom line: It can be done, but you'll end up with a laser that puts out 1W of green for a few seconds at most. It's not feasible, practical or useful.

Sorry to be a killjoy, but I'm just trying to put some of the facts about why it hasn't been done yet out there. Mind you, they're working towards it, and if it could be done, it would have been done long, long ago.

haha, yeah I was kinda joking about the 1W 473

at 5mW normally around $250, give or take a little bit. Lets times that by 200..... $40,000 for 1W. And let's say cni was nice about it?$10,$20 grand??>

OK.

5mW of quality CNI 532 costs $45.

By that logic, 100mW would cost $450. The 100mW PGL-III-C is only $285. (or was, according to GB #10 prices).

800mW would cost $7200. Now, the 800mW labby costs a hair under two grand.

It's non-linear. Like KTP. Laugh if you get it.
 
Last edited:
Put it this way- yes, they have a very high TDP, and like you said, up to 12W of heat energy to be dissipated.

Now, in those hosts, the main priority is getting the heat out of the LED, and keeping it below it's operating temperature ceiling, which, for the P7, happens to be 85C. Now, as long as the LED stays below that maximum operating temperature (we're looking at a realistic margin of around 60-70C here), it's happy. You just want light out.

In most cases the LEDs operate around 50C or so, with a host temperature of 40C or thereabouts. I'm not a flashlight geek, that's csshih's job to give you exact numbers. I'm just going off numbers I've gotten from similar heat loads with similar styled heatsinks. Anyway, I digress.

And in all of these cases, the LED requires no thermal stabilisation beyond 'keep it below X temperature'. That's it, that's all it needs. And within that temperature range, it's happy. Just feed it electrons, and it gives you photons in return, and heat.

Now, with a DPSS laser, we know two things.

  1. The diode will need temperature stabilisation
  2. The Nd:YVO4 will be better off with temp. stabilisation
  3. The KTP will also need temperature stabilisation

How many of the above does a torch provide? None.

First point- the diode needs temperature stabilisation. Without it, the diode's wavelength will fluctuate as much as 3 or so nm going from 20 to 60C, not to mention most diodes don't even have an operating temperature ceiling that high.

Now, with an LED, a 2-3nm shift wouldn't be noticeable. But when it's used to pump a gain medium, even a 0.1nm shift will be noticeable in terms of power output. That's why just about every labby out there has some form of temperature stabilisation- if you want it to be even remotely stable in operation, temperature regulation is a MUST.

The world's most powerful handheld green, the Hercules (by Laserglow and CNI), uses a fan in conjunction with a TEC element inside to keep the diode within operating spec, and that only has a peak of 800mW.

Even though Nd:YVO4 has a very large absorption spectra (compared to Nd:YAG, for example), wavelength changes WILL be felt in terms of power output. I don't have any graphs on me at the moment, however, someone around here does (Cyparagon? wannaburn?), and the effect is clearly noticeable when you're using a bodgy pump diode.

Second point- the KTP and YVO4 are also temperature sensitive, however, the KTP is more sensitive than the YVO4. In many of the labbies on the market, the YVO4 shares a TEC with the pump diode, and the YVO4's happy with that. It doesn't need much in the way of stabilisation, but what it does need is some form of cooling, so that the thermal shock that results from having watts of power ass-rammed into it at any given time doesn't crack or distort it, both of which will lead to catastrophic (as in, O LOOK TEMwtf!@:D!) failure of the laser.

Third point- same goes for the KTP, except it's more prone to damage. With intracavity doubling, the intracavity power will be higher than the pump power, or the output power. It's a resonant cavity- not all power will get converted to 532nm and make it out. If it were a straight-through superradiant 'laser', the intracavity power (and power through the KTP) will be significantly lower than the pump power. However, in a resonant cavity, with a 95% reflective OC, even a 5mW green pointer will have many watts of power circulating around. You can imagine the deal with a 5W pump.

Now, the problem is, KTP doesn't like high power densities very well, it suffers from grey tracking, as well as generally falling apart from stress fractures. But unlike the pump diode, KTP prefers to be heated, often to 0.1 of a degree for optimal efficiency. That degree of precision isn't necessary in a handheld, however, some form of temperature regulation is needed.

There's also a fourth point about dichroic coatings of the OC and HR shifting with temperature, but the wide linewidth of Nd:YVO4 more than makes up for that. Or, as this know-it-all-and-is-always-right member of Photonlexicon would point out, it'll turn into a multiline argon. Turn up the current, and you get more lines! Yay! And I quote "457nm, 473nm, SHG, SFG and SFG of SHG, and SHG of SFG". Now, ignoring the fact that KTP doesn't even double below 500nm because it can't be phase-matched (well, there's ppKTP, but that can only be matched to a single wavelength, meaning it only works at that wavelength, definitely ruling that theory out). Also ignoring the fact that if 946, 1342 and 1319 could be superradiant in a cavity tuned for 1064 only (and provide enough power to induce SHG in a crystal that can't even double blue, well, we wouldn't have such crap efficiency with those wavelengths, now, would we? Not to mention that if KTP could double below 500nm, nobody would bother with LBO, as it's a PITA to work with. Oh, and when I pointed that out, I got kickbanned from their IRC by said member. So, a member's unverified, unconfirmed results, (apparently nanowatts of 473 were detected), taken using an unknown laser, on an unknown instrument, is now more valid and reliable than a source that has been published many, many times, as well as being peer-and-publisher reviewed (namely RP-Photonics and Solid State Laser Engineering). Any attempt to question the inherently questionable nature of the observation, which just so happens to go against just about everything published on the topic, will earn you a kickban.

And you wonder why PL members have a bad name. You know what they say, it's the few that make everyone look bad. :yabbmad:

End rant. I'm having a bad day, and this is vaguely relevant.

The bottom line: It can be done, but you'll end up with a laser that puts out 1W of green for a few seconds at most. It's not feasible, practical or useful.

Sorry to be a killjoy, but I'm just trying to put some of the facts about why it hasn't been done yet out there. Mind you, they're working towards it, and if it could be done, it would have been done long, long ago.



OK.

5mW of quality CNI 532 costs $45.

By that logic, 100mW would cost $450. The 100mW PGL-III-C is only $285. (or was, according to GB #10 prices).

800mW would cost $7200. Now, the 800mW labby costs a hair under two grand.

It's non-linear. Like KTP. Laugh if you get it.


I was talking about 473nm, not 532nm. And I was laughing when I posted that, I have no idea what a real 1W 473nm would cost, if it is even possible. I understand green is much cheaper than 473nm and have gotten a rough quote from CNI on both wavelengths at different powers, my post was more of a joke than literal.

:beer:
 





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