An international team of scientists report that they have successfully used acoustics to deflect laser beams in an engineering first.

Laser Beams Deflected Off of Nothing but Air for First Time Ever in Breakthrough Patent Pending Process - The Debrief::An international team of scientists report that they have successfully used acoustics to deflect laser beams in an engineering first.

  • Slowy@lemmy.worldEnglish
    70·
    1 年前

    I didn’t know the answer to this so I looked it up - yes. Over 120 Db can cause damage even if it’s ultrasonic and you can’t hear it. Apparently at 155Db the heat created by the sound wave can be dangerous as well.

    • Kazumara@feddit.deEnglish
      40·
      1 年前

      Just a small note, it’s written dB, small “d”, big “B”.

      “B” is the unit symbol for bel and “d” is the symbol for the SI prefix deci, a tenth.

        • Kazumara@feddit.deEnglish
          3·
          1 年前

          Oh yes, sure you can, 140 dB is 0.000014 MB. The confusing thing is just that the non-SI unit byte also uses the symbol “B” and uses the SI prefix “M” quite often.

          Sometimes when I calculate optical power levels I actually use B in between. For example:

          How much signal is 88 optical channels at 1.6 dBm of power each?

          0 dBm = 1 mW by definition

          1.6 dB = 0.16 B = log10 ( x ) --> x = 10 ^ 0.16 = 1.45

          So 1.6 dBm is 1.45 * 1 mW = 1.45 mW

          Then 88 channels is 88 * 1.45 mW = 127.60 mW = 127.60 * 1 mW

          log10(127.60) = 2.11 B = 21.1 dB

          So 127.20 mW is 21.1 dBm, just below the output specification of our amplifier, good, nothing should melt.