[Laser] DPSS Lasers

[Dave]

> Date: Fri, 01 May 2009 16:46:35 +0200
> From: w.fritz at htp-tel.de
> Subject: [Laser] Looking and Learning About Solid State Lasers
> To: Laser at mailman.qth.net
> Message-ID: <20090501164635.9kan94u8e5x4cok8 at webmail.htp.net>
> Content-Type: text/plain; charset=ISO-8859-15; DelSp="Yes";
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> 
> Hi Stan,
> Diode Pumped Solid State Lasers are converted two times in wavelength.  
> First, a 808nm diode laser pumps a special crystal which emits  
> infrared laser light at 1064nm. This converted light is  
> frequency-doubled by another crystal to 532nm, visible green.
> Beside the very slow rise and fall time, DPSS lasers only have a very  
> bad efficiency. There are just 10 percent from the optical input power  
> at 808nm leaving the last crystal at 532nm. And they need a nearly  
> constant environment temperature around 25 degrees celsius. Otherwise,  
> the efficiency will decrease fastly near to zero.
> If you want to set up a high-speed communication unit via laser, it is  
> better to take a diode laser directly, such as a DVD writer laser  
> (around 100mW visible red). They are much powerful and fast enough for  
> high speed data communication or TV signals.
> We made 83,3km with a TV signal with 80mW red.
> Best regards
> Wilfried, DJ1WF

For those serious about pumped lasers and second harmonic generation,
take a look at his article:

<http://blog.makezine.com/archive/2009/04/homegrown_laser_crystals.html?CMP=OTC-0D6B48984890>

Dave