An "electric eye" alarm detects a break in the beam of light not with a simple "electric" cell but with this type of cell
The use of a single electric eye and a reflector mounted on the cart 
tray do ... cart which does not require aligning a light beam, reflector, and 
photoelectric cell, ..... 11, the bar-type magnet 24a is mounted to the lower tray 66 
such that a line... [DOC] [TLE] New Inventions that Baffle Crooks | Modern Mechanix [PAR] Jul 24, 2006 ...