variable size pinhole

A friend showed me a gadget which might work as a variable size pinhole.
It is a surplus iris and tiny stepper motor assembly, I assume from some
kind of camera. There are three iris blades which can close completely,
or open to about 1/4 inch. When very small, the hole is triangular.
The stepper motor should probably be removed as it has detents which
try to hold the iris at certain positions, probably larger than we want.
The stepper motor has a spur gear which engages a gear sector on the iris,
or there is a lever like thing which can also change the iris.

It is available from All Electronics for $ 1.25 each and is item
CAT# SMT-41 MINI STEPPER MOTOR/ IRIS MECHANISM.

http://www.allelectronics.com/
Received on Thu Jan 17 11:38:32 2002