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lasers

Posted: Tue Jun 15, 2010 2:09 pm
by bryuly
If I am changing from a diode laser to more powerful pulse laser, what changes should I expect to have to make? They are both Green lasers, but the pulse laser will be significantly more powerful. How do I make sure I get the proper exposure? Is there anything I need to compensate for since it is now a pulse?

Any help is appreciated. If you need more info let me know and I will do my best.

lasers

Posted: Wed Jun 16, 2010 1:01 am
by Colin Kaminski
What is the pulse power and duration?

lasers

Posted: Wed Jun 16, 2010 11:50 am
by Ed Wesly
Or more to the point, what is the manufacturer and model of the laser? Pulsed holography has quite a few different parameters to worry about.

lasers

Posted: Tue Jun 29, 2010 10:38 pm
by bryuly
Well I know that it is a Coherent Verdi Laser 2 Watts. I don't know the others right off the top I will look tomorrow. Where would I look to find the power and duration anyways?
Sorry I haven't been on in a little while. I appreciate the help.

lasers

Posted: Tue Jun 29, 2010 11:15 pm
by Colin Kaminski
The Verdi I saw was not a pulse laser. Did Coherent make a pulse version of the Verdi?

lasers

Posted: Wed Jun 30, 2010 1:36 pm
by bryuly
What do you mean by saw? I can look at it and it looks continuous; however, I was told it pulses very rapidly. Is this different than a pulse laser that is normally talked about? Can I just treat the laser as a continuous one and take time average holograms still?

lasers

Posted: Thu Jul 01, 2010 5:48 am
by wler
bryuly wrote:What do you mean by saw? I can look at it and it looks continuous; however, I was told it pulses very rapidly. Is this different than a pulse laser that is normally talked about? Can I just treat the laser as a continuous one and take time average holograms still?
If it is a mode locked or rapidly Q-switched laser then this is not suitable for doing holography, IMHO.

lasers

Posted: Thu Jul 01, 2010 6:30 am
by Tom B.
The Coherent Verdi series are CW (continuous wave) lasers.

http://www.coherent.com/lasers/index.cf ... 73&loc=834

I think the confusion may have arisen because these lasers are often used to pump Ti : Sapphire lasers
in femtosecond pulsed applications. But the Verdi itself does not pulse.

lasers

Posted: Thu Jul 01, 2010 7:19 am
by wler
Actually as far as I know the Verdi is one of the best lasers around, for holography, with 10+ Watts 532nm CW single mode. There is an experiment nearby that I visited (actually for calibrating my power meters) and the people had this laser running and were full of praise.

lasers

Posted: Thu Jul 01, 2010 11:23 am
by JohnFP
A Verdi laser is great for holography. I would simply love to play with one of them. And Tom is correct it is a CW laser.

So back to your original question. The best answer I can give is get a light meter. Here is a very good one that can handle the power and is inexpensive so to speak. I have this one and it works great.

http://www.tftelectronics.co.uk/TFT%20L ... 0Meter.htm

While you wont be able to use the meter in the unexpanded raw beam, once your beams go though the spatial filter, you will be able to read power. Then just follow the guidelines for the film you are using for total energy and adjust your ratios as needed for the type of hologram you are making.