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Re: Speech sensors?



At 10:11 12/26/97 -0500, you wrote:

I once tried it with a 5mW HeNe laser and a photocell to detect
vibrations reflected from the window glass. It didn't work for me
but it might work with an optical system to concentrate the
reflected light on the photocell and sensitive amplifiers at
the receiving end.

Herb Gottlieb

I fancy that a telescope used to acquire the laser spot would
have helped your chances.
It's quite easy to think of schemes for improving the
signal/noise of the received signal.
Modulating the laser diode beam at say 100 kilohertz would allow
a photodiode or photomultipier tube to drive a narrow band amplifer
into a synchronous detector, for instance.

brian whatcott <inet@intellisys.net>
Altus OK