Re: combining laser beams

[John Gastineau <jgastineau@VERNIER.COM>]

> > > > > > > > > > > > >
> > > herbgottlieb@JUNO.COM 12/12/02 08:09AM >>>
On Wed, 11 Dec 2002 21:25:39 -0500 Ludwik Kowalski
<kowalskil@MAIL.MONTCLAIR.EDU> writes:
> I forgot to add the obvious, the "amplifier" must received
> energy to populate excited levels. I suppose this can
> be done with visible non-coherent light.

Please explain a possible mechanism by which non-coherent
light can provide the energy to to populate ther excited levels
Has it ever been done already?   If so, where can I find out
more about it?


> > > > > > > > > > > > > > >

A ruby laser uses flashlamps to create the population inversion, so
this has been done long ago.

Note that a laser amplifier is relatively easy to make--it is just the
optical medium with a population inversion and no optical cavity. You
pass a low power beam through the medium, and stimulated emission takes
place. In a very crude sense, you're cloning the photons of the original
beam, so the beam quality at the output is similar to that of the input.


There are advantages to using a low-power laser (called the oscillator)
and a stage or three of amplification, instead of a strongly-pumped
laser consisting of only the oscillator (optical medium with inversion
surrounded by an optical cavity, a.k.a., the mirrors).

J Gastineau