Re: The sound of a laser.

From: David Prokopetz (sirbob_at_penguinking.com)
Date: 08/20/04 

Date: Fri, 20 Aug 2004 09:53:52 -0600

"Harvey Rutt" <xh.ruttx@x.ecs.soton.ac.uk> wrote in message
news:4125b487@news.ecs.soton.ac.uk...
>
> "David Prokopetz" <sirbob@penguinking.com> wrote in message
> news:2ol510Fbmdq4U1@uni-berlin.de...
> > Hi.
> >
> > Physics newbie question here: what does a laser sound like?
>
> The great majority of lasers are silent, listen to your laser pointer or
CD
> player (with the volume turned down) :-)
> A few (less nowadays) make minor pops & bangs from the *power supply* or
> flash lamps.
> The odd one, as in those excited by a nuclear bomb or some kilograms of
high
> explosive, make a very low noise indeed, but they are rather rare!
>
> > Some sources
> > I've read claim that a sufficiently powerful laser would ionise the air
> > along its path and produce a "crackle" or "pop" noise, while others
claim
> > that regardless of power, a laser has to be of a particular colour to
> ionise
> > the air and thus produce a sound - but fail to mention what that colour
> is.
> > Is any of this information accurate?
>
> This is now the interaction of the laser beam with the air, not the laser
> *itself*.

<snip>

Well, yes, I think we can safely assume the presence of air when talking
about sound. ;)

Thanks for the information, though.

 - David Prokopetz.

Relevant Pages

  • Re: The sound of a laser.
    ... what does a laser sound like? ... > I've read claim that a sufficiently powerful laser would ionise the air ... If the electrons in the "air" atoms are able to absorb light energy ... which may absorb or scatter the light as they drift into a continuous beam. ...
    (sci.optics)
  • Re: "laser" microphone
    ... Something about air going through a tube and being scanned ... Anybody know anything about "laser" microphones? ... measurement that grow as the scale is reduced to molecular dimensions. ...
    (rec.audio.pro)
  • Re: "laser" microphone
    ... Something about air going through a tube and being scanned ... Anybody know anything about "laser" microphones? ... C'est suisse, et tres, tres precis." ...
    (rec.audio.pro)
  • Re: The sound of a laser.
    ... > I've read claim that a sufficiently powerful laser would ionise the air ... > the air and thus produce a sound - but fail to mention what that colour ...
    (sci.physics)
  • Re: The sound of a laser.
    ... > I've read claim that a sufficiently powerful laser would ionise the air ... > the air and thus produce a sound - but fail to mention what that colour ...
    (sci.optics)