At 03:49 PM 11/14/97 -0500, you wrote:
>For those of you that have done low cost (consumer product) motion sensors,
>the type that turn on lights when people enter the room etc....
>
>what do you recommend?
>I'm currently looking at a Hamamatsu  Pyroelectric detector,
>what about IR?
>what else?
>
>What's the easiest (lowest parts count) method?
>
>Thanks......
>Jason Wolfson
>Lipidex Corp.
>
>Attachment Converted: "D:\EUDORA\ATTACH\lowcostm.htm"
>
I've worked with IR motion sensors for quite a number of years. There are
lots of pretty good detectors available at reasonable prices. Almost all IR
motion detectors use the pyroelectric detectors. Your real problem is going
to be the lens. You need a segmented lens to get the system to work, and
that is going to be hard to find.

If you are trying to build a project where the motion sensor is just part
of the total project (such as a Security System which uses motion sensors)
I'd suggest
biting the bullet and buying a commercial motion sensor; the're really
inexpensive.You could use the on of the outdoor lights with motion sensing:
that way you have the whole sensor including power supply. All you have to
do is pick off the output signal to the relay or triac.
Mark Walter