RE: Melanoma cancer/UV info

["Wright, Will (DHS-PSB)" <WWright2@dhs.ca.gov>]

That answers the beam production question, what about the "purity" of the
apparent monochromatic beam.  Is the characteristic color due to the
absolute 100% simultaneous shifts or is there some fluctuation between say,
90 and 100.  Ordinary light is dispersed over short distances as well.

		-----Original Message-----
		From:	ruth_weiner [mailto:ruth_weiner@email.msn.com]
		Sent:	Thursday, August 10, 2000 8:33 PM
		To:	Multiple recipients of list
		Subject:	Re: Melanoma cancer/UV info

		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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