Main and auxiliary film projector unit - has manual facility for opening rotary shutter and rear blanking shutter to direct light through auxiliary unit

摘要

A film projector (1) has a facility for an auxiliary projector (2) to be used with and in front of it. The rotary shutter (8) in the main projector can be manually turned (16). Coupled to the manual gear train is a contactless switch unit (11, 12) controlling a magnet (21) which, in turn, lifts a shutter plate (7) in the optical light path to let light pass when the rotary shutter is open. A signal light coupled to shutter plate magnet circuit indicates when the plate is lifted and the rotary shutter stationary. The light path travels through lens (5) in the primary projector (1) and a lens (6) in the auxiliary projector (2).