[Laser] reflex optical switch

[Tim Toast]

Here's a rough diagram of a "straight through" optical switch
http://www.aladal.net/toast/reflexoswitch1.jpg
 
I thought a small DC motor would make a good axis for the mirror and move it back and forth.
To make the mirror "latch" you could put magnets near the stops and glue small pieces of 
steel to the mirror so it will be attracted to the magnet when near it (but not touching). This 
will hold the mirror securely against the stop when it gets close. Then you can give the motor 
a pulse of one polarity to latch it "up" and a pulse in the opposite polarity to latch it "down".
 
-toast