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Old April 29th 05, 04:14 PM
Richard Clark
 
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On Fri, 29 Apr 2005 00:37:12 -0700, "John Smith"
wrote:

I wonder if a LED is not "strobed", either occuring as a natural property of
the LED itself, or circuitry incorporated on the LED chip, itself, which
"strobes" it?


Hi Brett,

The voltage supplied to the LED elevates the electron out of one
orbital to the conduction band. When it falls back, a photon is
emitted. The wavelength of the emitted photon is the path length the
electron follows spiraling from one orbital to the other (DeBroglie
wave).

There are no lasers that are pumped in a cyclic sense except those
that emit a pulse like the old CO2 UV lasers. I had a buddy who built
one that used plate glass and aluminum foil to build the high voltage
charge used to excite the gas to lasing (you still need an optically
resonant chamber to build the intensity).

This design, from the pages of Scientific American's Amateur Scientist
column exhibited a very high peak power because of the extremely short
pulse duration. His knowing this instilled the caution to aim it out
the window into free space for its inaugural firing. When he pulsed
it he cracked the window. Window glass is not perfectly transmissive,
and the high peak power and short interval conspired to create a very
hot dislocality - the glass couldn't shed the heat fast enough and it
cracked.

73's
Richard Clark, KB7QHC