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Posted: 6/13/2003 5:18:45 PM EDT
copied from a source that i can't remember so i don't have a link...

"The reason for the high price of green pointers as compared with red lies in their additional internal complexity. They use a battery powered laser diode controlled by a miniaturized circuit, just like the red ones. However, the diode uses about five times the power of the red ones and emits it's laser light at an invisible, infrared wavelength of 808nm. The infrared laser output is focused into a small crystal of Neodymium doped Yttium ortho Vanadate (NdYVO4), which then lases at a longer wavelength of 1064nm. The 1064nm output beam is absorbed in an adjacent crystal of Potassium Titanyl Phosphate (KTP) which resonates at twice the pump light frequency to produce an output of 532nm green laser light. A multilayer interference filter removes residual infra-red light, and the output is focused and collimated into a thin parallel beam. Both of the crystals are artificially grown, and must be cut, polished, and multi-coated to very small tolerances. Only a handful of companies are producing these crystals now."

jeeez, who thinks up this stuff?!?



Link Posted: 6/13/2003 6:43:11 PM EDT
Sounds like Craig from the LED Museum: [url]http://ledmuseum.home.att.net/mega1.htm[/url] [url]http://ledmuseum.home.att.net/laser.htm[/url]
Link Posted: 6/13/2003 7:03:23 PM EDT
I call [BS] they said the same thing about the red lasers when they came out. I don't KNOW this cuz I don't work with the materials, but I doubt it cast's any more to make a green laser than a red one. Propaganda to raise prices.
Link Posted: 6/13/2003 7:06:33 PM EDT
Interesting! Have any info on blue laser?
Link Posted: 6/13/2003 9:06:26 PM EDT
[Last Edit: 6/13/2003 9:07:27 PM EDT by militarymoron]
Originally Posted By LotBoy: Have any info on blue laser?
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they use dilithium crystals and those are WAY more rare [:P] MM
Link Posted: 6/13/2003 9:11:39 PM EDT
Originally Posted By militarymoron:
Originally Posted By LotBoy: Have any info on blue laser?
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they use dilithium crystals and those are WAY more rare [:P] MM
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Thank you Captain Kirk.
Link Posted: 6/13/2003 10:55:24 PM EDT
Let me prface this question by saying I know jack sh!t about diodes and crystals. I have heard people talk of converting red lasers to IR by replacing a diode. I was wondering if converting a green laser to IR might be easier. Might it be done just by removing a "part"? Or am I jsut making sh!t up that is imposible?
Link Posted: 6/14/2003 11:59:29 AM EDT
I thought of the same thing my frined but the IR laser is focused to the next crystal. Youd have to refocus the laser and thats not an easy task. This is all paraphrased from a guy I met who sells laser and NV gear and I may have just done a hack/butcher job to his wording.
Link Posted: 6/14/2003 9:21:35 PM EDT
Makes sense.
Link Posted: 6/15/2003 3:19:16 AM EDT
Back in the 80's the Reagan administration gave University of Rochester a s-load of money to change their Optical Engineering lasers to blue to aid in "star wars" research.
Link Posted: 6/15/2003 2:40:03 PM EDT
Originally Posted By bvmjethead: I don't KNOW this cuz I don't work with the materials
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You can always argue with this guy [;D] Sam's Laser FAQ [url]http://www.repairfaq.org/sam/lasersam.htm[/url] Dissection of Green Laser Pointer [url]http://www.repairfaq.org/sam/laserpic/glpdpics.htm#glpdtoc[/url]
Link Posted: 6/15/2003 2:46:46 PM EDT
[Last Edit: 6/15/2003 2:51:57 PM EDT by gregw45]
Originally Posted By LotBoy: Have any info on blue laser?
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Get your gold card ready! [url]http://www.candlepowerforums.com/ubbthreads/showflat.php?Cat=&Board=UBB3&Number=262569&page=0&view=collapsed&sb=5&o=&fpart=1[/url]
Link Posted: 6/15/2003 3:01:41 PM EDT
Originally Posted By gregw45:
Originally Posted By LotBoy: Have any info on blue laser?
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Get your gold card ready! [url]http://www.candlepowerforums.com/ubbthreads/showflat.php?Cat=&Board=UBB3&Number=262569&page=0&view=collapsed&sb=5&o=&fpart=1[/url]
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HOLY CRAP those are expensive![wow] Thanks for the link.
Link Posted: 6/15/2003 9:41:51 PM EDT
(Raising my hand) Hello, laser geek here. I work with these wavelength lasers daily. The article accurately describes how most green diode lasers work. They pump the Nd:YV04 (that’s the 'laser rod' in this case) with the ~800nm to emit IR and then double the freq with a non-linear crystal like KDP* to get to green. (But the crystal cuts the power in half too-thats why the pump source is much higher power than a 5mw red pointer.) I hope the KDP* is sealed tight in those pointers- if atmosphere gets to them they will fall apart fast. The article is also correct in another point- the crystals are low production and hard to work with. Sorry guys- green lasers do cost more due to the components. I have never had a laser installed on any weapon I have ever owned but I can set my neighbors fence on fire with the IR/green 20 watt laser in my garage. [wink] J
Link Posted: 6/15/2003 10:23:33 PM EDT
[Last Edit: 6/16/2003 11:12:52 AM EDT by PhillipKP]
Hi! I'm a laser physicist. Ditto what fellow laser jock jasondcrum said. What you are paying for in a green/blue laser are the doubling crystals. It's the most expensive part in a green laser. You can't just pick these up on some cave somewhere. These have to be grown in the lab under very tight tolerances. Also photon to photon, blue/green photons have twice as much energy than red/IR photons. That means you're using twice as much energy. Thats because it takes two red/IR photons to make one blue/green photon. Doubling the frequency of light involves many physical parameters. The crystals will only double the light at certain directions, orientations, and power. This is why focusing is SO important. We have a 5 watt ND:Yag green pump laser in our lab. We paid 60,000 dollars for it. That was the cheap model. Research grade doubling crystals alone can run upwards of 20,000 depending on the size.
Link Posted: 6/16/2003 1:30:58 AM EDT
So was Darth Vader just a cheap ass with his red lightsaber? I mean, Luke sprang for the green laser and it worked great for him. [%|]
Link Posted: 6/16/2003 7:19:40 AM EDT
Lmfao
Link Posted: 6/16/2003 11:15:24 AM EDT
LOL. Yeah but Vader's death star has to be the biggest freaking laser in the universe.
Link Posted: 6/16/2003 11:21:16 AM EDT
I'll take an IR/Green Laser rifle in the 20W range. Heh heh [:D] Bob
Link Posted: 6/16/2003 3:06:12 PM EDT
Not my pic... just someone playing with the neighbors. [}:D] [img]http://www.imagestation.com/picture/sraid61/p4441685da75c4b8407e6f84df148fe99/fc2e8100.jpg[/img]
Link Posted: 6/16/2003 3:56:00 PM EDT
[Last Edit: 6/16/2003 3:58:06 PM EDT by Master_Blaster]
Originally Posted By 762mmMAN: So was Darth Vader just a cheap ass with his red lightsaber? I mean, Luke sprang for the green laser and it worked great for him. [%|]
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Yeah, well, he [i]had[/i] a blue one, but probably couldn't afford a another after he foolishly set it aside for his boy (Who [i]lost[/i] it & got a good a$$-whoopin' from pop. I'd whoop his a$$, too [buttkick]). Hence, he had to settle for the tried-&-true red Sith death stick.
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