Modulation and Pulsed Laser

Discussion in 'The Lounge' started by sheen, Dec 16, 2007.

  1. sheen

    sheen New Member

    I really do not know much about laser. But I need a pulsed laser with duration about 100ns or less. The repetition rate should not exceed 2 kHz (slow rate with more concentrated energy in each pulse is best). I have seen many laser modules with TTL modulation mode. Are these pulsed lasers? If it is, what is the typical duration of each pulse?

    And how to implement TTL modulation? Can I use a function generator to generate square waves as the input?
  2. FunkyDoctor

    FunkyDoctor Member

    Hi Sheen,

    laser light show lasers are normally cw lasers. TTL modulation means, that the controlling software will be able to blank this (cw) laser, if the beam is not needed. It's difficult to use pulsed lasers for scanning graphics or beams. Normally (if using cw lasers) you synchronize scanning and blanking/color mixing with each other. A pulsed laser blanks on his own (repetition rate). So you will get funny or strange effects in your scanning (sparkling, bright areas, dark ares or areas without output). Even if you are using pulsed lasers with repetition rates of about 30kHz, you will have these effects. This is why scanned laser light shows always use cw lasers. We use only one type of pulsed laser...but this one is doing 80MHz!!!