Re: Melanoma cancer/UV info

["ruth_weiner" <ruth_weiner@email.msn.com>]

Just a note about lasers: LASER is an acronym for Light Amplification by
Stimulated Emission of Radiation.  The ruby is not a filter, but the source
of the laser light.  A laser is "primed" by creating a metastable situation
where an energy state above the ground state (lowest potential energy) is
overpopulated with electrons.  When stimulated, the electrons drop
together -- in phase -- from the higher energy state to a lower one.  the
characteristic red light of a ruby laser is this emission.  Laser light is
coherent -- the waves are all in phase -- which gives it its unusual
penetrating power, and which is why you can bounce a laser beam off the
moon.  Ordinary light (e.g. red neon light) is incoherent and disperses when
beamed a long distance.

Ruth Weiner
ruth_weiner@msn.com
-----Original Message-----
From: Wright, Will (DHS-PSB) <WWright2@dhs.ca.gov>
To: Multiple recipients of list <radsafe@romulus.ehs.uiuc.edu>
Date: Thursday, August 10, 2000 2:24 PM
Subject: RE: Melanoma cancer/UV info


>Visible light from fluorescent lamps produce UV in addition to the total
>spectrum of visible light waves as well which combined appear as
>white(heterochromatic) and very dispersed.  Fluorescent lights are filtered
>with the plastic cover to reduce the UV levels.  Lasers produce
>monochromatic light either red or green and can concentrate the beam, I am
>not sure these beams are pure since the rubies etc used act as filters
only?
>These concentrated beams produce heat much the same way radiowaves and
>microwaves do and indirectly form reactive products that might effect DNA.
>



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