this post was submitted on 22 Oct 2023
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Laser Beams Deflected Off of Nothing but Air for First Time Ever in Breakthrough Patent Pending Process - The Debrief (thedebrief.org)
submitted 1 year ago by L4s to c/technology
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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.

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[–] [email protected] 3 points 1 year 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.