Re: length of wavetrain of single photon

Brian-

Sorry for the delay. Your laser should have a reference dispersion
area for a given target distance. For example, I am looking at a Verdi
V5 manual here and it lists the beam diameter as 2.25mm +-10% at the
exit port with a full angle divergence of .5mrad. Surface beam area
then becomes a function of distance.

-herbie

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