Jon:

 An optoisolator is a device which transfers information by means of a beam
of light (usually in the infrared range) from an emitting diode to a
detecting diode or transistor or thyristor device. The diode circuitry is
electrically independent (isolated) from the transfer device (diode,
transistor or thyristor).  The only thing that links the input event to the
detecting system is the beam of light so the two systems can have
independent power circuits.  If this is too basic, and you really want the
answer in terms of the physics of the phenomenon, I appologize. Let me
know.

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> From: PHXSYS <PHXSYS@aol.com>
> To: PICLIST@MITVMA.MIT.EDU
> Subject: optoisolator, simple explanation
> Date: Monday, April 27, 1998 1:24 PM
>
> I was hoping someone could provide a simple explanation of an
optoisolator and
> an example of its practical use.
>
>
> Jon