On Wed, 27 Sep 1995, Stuart Allman wrote:

> I'm looking for a way to create a small pad where I can put sensors at
> the corners and have them recognize where an object is in the area.  I
> was thinking about doing it with magnetic fields, but there's no flux
> change unless I move the object.  Is there any way to do this with an IR
> transmitter.  The area is limited to 10cm x 10cm and it has to be
> sensitive to within 0.1 mm.  The source of movement can't be a
> directional, because the signal must be picked up no matter where the
> object is.
>
> Stuart Allman
> studio@halcyon.com

You might want to try modifying an old Koala Pad (a touch pad made
for Apple & Commodore computers). I think that Radio Shack used to
also sell a version of it. How heavy is your object?

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