Page 4 of 4 FirstFirst 1234
Results 31 to 38 of 38

Thread: Viasho 4W 532nm Laser System Review!

  1. #31
    Join Date
    Jan 2007
    Location
    Cupertino, California
    Posts
    2,130

    Default

    Alright guys, I just tested the beam, measured 2.2mm at the aperture and a almost exactly 25mm at 50 feet. This calculates out to a divergence of 1.496mRad. Very nice beam for a laser of this size/power! It is very round and runs in TEM00 mode for the time I have observed it.

    Modulation to come next!
    CLICKY!!!

    Admin: In the immortal words of Captain Planet: YOU HAVE THE POWER
    Admin: (To quit being a bitch)

  2. #32
    Join Date
    Mar 2009
    Location
    Wesbury, Wilts,, England
    Posts
    125

    Default

    Ben,

    How much is it ?

  3. #33
    Join Date
    Oct 2005
    Location
    Melbourne, Australia
    Posts
    678

    Default

    Yeah, test the modulation.
    Now proudly stocking and offering the best deals on laser-wave

    www.lasershowparts.com
    http://stores.ebay.com.au/Lasershow-Parts

  4. #34
    Join Date
    Jan 2007
    Location
    Cupertino, California
    Posts
    2,130

    Default

    Okay, modulation results! All tests are on TTL+ input (friend still has my function generator ). All inputs are 5V square wave at full power. Laser was sent into an integrating sphere with an avalanche photodiode and measured on a scope. In some of the pictures, there is the modulation input shown as input B. It shows as 50V/Div, but it was set on 10:1 scale so it is really 5V/Div.







    CLICKY!!!

    Admin: In the immortal words of Captain Planet: YOU HAVE THE POWER
    Admin: (To quit being a bitch)

  5. #35
    Join Date
    Jan 2009
    Posts
    1,622

    Default

    Not bad at all!.. is it possible to use some other waveforms to observe linearity while ramping up to 5V over time rather than instantaneous TTL type stuff?

    EDIT nvm.. just saw the part about the function generator..

  6. #36
    Join Date
    Jan 2008
    Location
    Stockholm, Sweden
    Posts
    799

    Default

    Potential is not a very good unit for measuring radiant power. I'd convert it into something that actually makes sense (W).

  7. #37
    Join Date
    Jan 2007
    Location
    Cupertino, California
    Posts
    2,130

    Default

    I don't have a sensor that can measure 0-5W full scale at very high speeds. This is about as linear as you are going to get, plus, it is only to see how the output rises and falls. If you want power measurements, go look on the first page.
    CLICKY!!!

    Admin: In the immortal words of Captain Planet: YOU HAVE THE POWER
    Admin: (To quit being a bitch)

  8. #38
    Join Date
    Jan 2008
    Location
    Stockholm, Sweden
    Posts
    799

    Default

    How about calibrating the photodiode you're using now against another power meter? Once you have made the power-response curve you can easily convert between the two.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •