I took a look on the Internet.  There's a company called Pentagon Defense
products who make a laser barrier to use around a swimming pool to prevent
a child falling in.  See http://www.pentagondefense.com.  It's listed under
the 'Home protection' menu.  A number of swimming pool suppliers offer the
system as well.

Laser2000 in the UK sell a laser transmitter/receiver combination, at
www.laser2000.co.uk

There's another company called Laseroptotronix who appear to provide
exactly what you want, for use at airports, for example, but their web site
is down (or maybe they are out of business).


>-----Original Message-----
>From: Museum discussion list [mailto:[log in to unmask]]On
>Behalf Of William Grewe-Mullins
>Sent: Wednesday, November 21, 2001 9:29 AM
>To: [log in to unmask]
>Subject: Laser barriers
>
>
>I am looking for a source of laser barriers to use in an upcoming
>exhibition. Basically, I'd like to protect specimens displayed behind a
>minimal physical barrier by adding a laser beam barrier that will set off
>an audible alarm when the beam is broken. Sonic curtains are not an option
>in this case. Thanks
>Wil
>
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Jeff Graham
Ansae Ltd
01453 843033
07771 865574
www.ipuppeteer.com

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