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  1. Standard member sonhouse
    Fast and Curious
    03 Apr '14 13:23
    http://phys.org/news/2013-10-art-amplification-desktop-size-terawatt-laser.html#nRlv

    Not as much power as it sounds like, terawatt femtosecond pulses=average power of about 10 milliwatts

    Correct me if I am wrong.
  2. 04 Apr '14 13:29
    Originally posted by sonhouse
    http://phys.org/news/2013-10-art-amplification-desktop-size-terawatt-laser.html#nRlv

    Not as much power as it sounds like, terawatt femtosecond pulses=average power of about 10 milliwatts

    Correct me if I am wrong.
    What happen if you point this laser to, let's say, the skin of a hand...

    (1) One pulse?
    (2) An time interval of pulses?
    (3) A continuous beam of concentrated light with the same average energy?

    10 milliwatts doesn't sound much. Neither does a femtosecond. But a terawatt sound like an awful lot.
  3. Subscriber Ponderable
    chemist
    04 Apr '14 14:16
    So we do have the journalist effect again.

    IF the pulse was 1 second it would have the power of 10TW = 10^12W.

    IF they could operate the equipment that long they would suck the whole European grid clean....

    so they operate for a femtosecond 10^-15 s and only have a net output of 10mJ. Since they can't produce more than one pulse per seond this come to 10mW.

    BUT you can do some weird multiplikations and get fantastic numbers.

    The LASER is save to operate, will do some good and won't suck the value of a few dozen nuclear power stations from the grid.

    And it is NOT a 10TW LASER.
  4. Standard member sonhouse
    Fast and Curious
    04 Apr '14 15:35
    Originally posted by Ponderable
    So we do have the journalist effect again.

    IF the pulse was 1 second it would have the power of 10TW = 10^12W.

    IF they could operate the equipment that long they would suck the whole European grid clean....

    so they operate for a femtosecond 10^-15 s and only have a net output of 10mJ. Since they can't produce more than one pulse per seond this co ...[text shortened]... ck the value of a few dozen nuclear power stations from the grid.

    And it is NOT a 10TW LASER.
    Yes, like I said, continuous power would add up to a 10 Mw laser but the pulses are compressed so that each pulse would act like a 10 terawatt laser for that brief time span.

    It would be like if you had an actual 10 terawatt laser and you had a shutter that could chop the output into a femtosecond pulse, the damage or processing done that way would be exactly the same as the 10 Mw laser time compressed to 1 femtosecond.
  5. 05 Apr '14 14:51
    You guys are all getting confused between Watts and Jules.

    This IS a TerraWatt pulse laser.
    The POWER output of the PULSE is 10 TW. [Jules per second]
    The ENERGY of the pulse is 10mJ [Power times Time]

    The average power output of the laser will of course depend on how many pulses you
    fire per second, but the energy density [power] of the pulse is indeed 10TW.
  6. Standard member sonhouse
    Fast and Curious
    06 Apr '14 18:34
    Originally posted by googlefudge
    You guys are all getting confused between Watts and Jules.

    This IS a TerraWatt pulse laser.
    The POWER output of the PULSE is 10 TW. [Jules per second]
    The ENERGY of the pulse is 10mJ [Power times Time]

    The average power output of the laser will of course depend on how many pulses you
    fire per second, but the energy density [power] of the pulse is indeed 10TW.
    Twu twu twu, I forget sometimes. I tried to say the same thing in my last post.