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·
    9 months ago

    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·
      9 months ago

      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·
          8 months ago

          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.