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Temperature stable laser emits green light

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http://optics.org/cws/article/industry/33263


A battery-powered solid-state green laser that emits constant power over a wide temperature range is now commercially available.

MiniGreen ETR series
Laser.jpg


Snake Creek Lasers of the US has developed a solid-state green laser that operates over a broad temperature range while maintaining constant laser output. The laser could be deployed in aiming applications for military/law enforcement and for guidance applications in industrial environments.

"For the first time, a battery-driven and temperature-stabilized green diode-pumped solid-state (DPSS) laser is available," Sten Tornegard, marketing manager at Snake Creek Lasers, told optics.org. "No green semiconductor laser currently exists, we have developed a frequency-doubled DPSS laser to fill in the wavelength gap between blue and red diode lasers."

The MiniGreen ETR Series provides 100 mW of continuous-wave output power at 532 nm over a 40[ch8201]°C temperature operating range with less than 2 W power consumption. Further power settings of 100 mW over 30 K, 100 mW over 40 K or 50 mW over 50 K are also available.
mailto:tom.houlden@iop.org

The performance of a DPSS laser (output power, mode quality and power stability for example) are inherently sensitive to changes in ambient temperature. In particular, the output wavelength of the pump diode laser varies by around 0.3 nm per degree C. "Power-hungry thermo-electric coolers (TEC) or ovens are required for reliable emission making DPSS lasers unsuitable for portable or battery-powered applications," commented Tornegard. "Snake Creek has developed a green DPSS laser with +/- 10% power stability over a 50[ch8201]°C range without TEC requirement, opening the laser up for demanding military and industrial applications."

According to Tornegard there is a strong incentive for switching to green lasers for laser pointer applications to guide human eyes in dynamic processes. Currently red lasers based on III-V semiconductor materials are commonly used for patient positioning, military aiming, and other laser pointer applications. "However, due to concerns for retinal damage, the maximum laser output power for TEM00 beams is limited to 5 or 1 mW in the visible wavelength region," he commented. "By substituting the red (540 nm) laser with an equal power green (532 nm) laser, visual sensitivity is improved by a factor of five in daylight and a factor more than 500 for a dark-adapted eye."

Although Snake Creek Lasers did not disclose details of its DPSS lasers, the company says that it will release more information later this month in the upcoming Defense & Security Conference in Orlando in the US. The company also plans to develop blue DPSS lasers based on its ETR technology.


Snake Creek Lasers http://www.snakecreeklasers.com
 





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interesting, but here i thought they had finally made green diodes

sounds like they just made a crystal that is less temperature sensitive
 
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Very very interesting. I couldn't find even the slightest hint as to how that is accomplished though. Any ideas?
 
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these are incredible news..

(not gonna be too happy if they start manufacturing these diodes and a 150mw laser gets as cheap as 10dls. each and every guy in the world starts having one..)
 

Razako

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nikokapo said:
these are incredible news..

(not gonna be too happy if they start manufacturing these diodes and a 150mw laser gets as cheap as 10dls. each and every guy in the world starts having one..)
They aren't diodes. They are just crystals that are less temperature sensitive.
 
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Razako said:
[quote author=nikokapo link=1205380725/0#5 date=1205382665]these are incredible news..

(not gonna be too happy if they start manufacturing these diodes and a 150mw laser gets as cheap as 10dls. each and every guy in the world starts having one..)
They aren't diodes.  They are just crystals that are less temperature sensitive. [/quote]

Naaah. The problem is that your typical Nd:YVO4 or YAG has a very narrow absorbance bandwith. If the pump diode is just off by a nm the wrong way, your efficiency can be decimated to a fraction of what it used to be. As the article says, it only takes a degree celsius to shift a regular 808nm diode's wavelength by 0.3nm, so this is a pretty interesting breakthrough to me. At the least, I'm very curious as to how its done. Different pump diode composition? Whole different type of crystal? Or some other trick? Or a combo of all that? I dunno but its got me stumped and stunned.
 
L

likewhat

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Well, I have used grating feedback into diode lasers and without temperature control the laser stays quite stable, maybe a few 10s of GHz at 780 nm which is ~.01 nm. If the temperature is kept constant with an extremely simple servo circuit (no feedback into diode) the diode can be kept quite stable. It wouldnt be hard to keep it withing 0.1 nm with a simple circuit. The stable diode systems I have used kept the temp to within 0.01 C, with grating feedback it kept the frequency within 1 Mhz @ 780 nm which is ~ 0.000002 nm
 

IgorT

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What is so special about this?

CNI is making a module like that with 100mW of green for 160€.. And i think it's a little shorter. Basically it looks like a big fat diode.. It's called S-GDL-532.

Here's the datasheet: http://www.cnilaser.com/PDF/S-GDL-532.pdf



EDIT: Or is it about a wider temperature range?
 




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