Results 1 to 2 of 2

Thread: Approximate power out from current?

  1. #1
    Join Date
    Sep 2007

    Default Approximate power out from current?

    It will be a while until I get around to buying a power meter so wondered is there a way to approximate the power output from a laser diode by using the current drawn?

    Thanks - Dave

  2. #2
    Join Date
    Mar 2006


    Look at a data sheet to find the current for a specified output, then assume that the ratio falls as you push harder, until more current won't get you as much output as you'd expect as increase. You can't reallly predict though, outputs for an exact current can vary more than 20% between diodes, and wavelength differences make it even harder to judge.

    The best way is to get a TEC, (Peltier) stick it to a block of aluminium, paint it black on the front side, then read the millivolts on its terminals when heating it with the beam of a known laser. Then you can measure and calculate with a simple constant linear ratio. For diode lasers this can be better than having a Lasercheck, because a TEC doesn't need to know the wavelength. It can also be accurate when more than one wavelength is there.

Posting Permissions

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