Automatic exposure control device

Claim 1

THE COMBINATION, WITH MEANS DEEFINING AN EXPOSURE APERTURE ADAPTED TO PASS INCIDENT LIGHT FROM A SCENE FOR EXPOSING FILM OR THE LIKE, OF AUTOMATIC EXPOSURE CONTROL MEANS COMPRISING: (A) MOVABLE OPENING AND CLOSING SHUTTER BLADES, EACH HAVING A BLOCKING POSITION OVERLYING SAID APERTURE AND AN UNBLOCKING POSITION UNCOVERING SAID APERTURE FOR CONTROLLING THE PASSAGE OF INCIDENT LIGHT THERETHROUGH; (B) FIRST COUPLING MMEANS RELEASABLY ENGAGED WITH SAID OPENING BLADE WHEN THE LALLTTER IS IN BLOCKING POSITION FOR RELEASABLY MAINTAINING THE OPENING BLADE IN BLOCKING POSITION; (C) MEANS TO DISENGAGE SAID FIRST COUPLING MEANS FOR SAID OPENING BLADE: (D) MEANS MADE EFFECTIVE UPON DISENGAGEMENT OF SAID FIRST COUPLING MEANS TO MOVE SAID OPENING BLADE FROM BLOCKING TO UNBLOCKING POSITION; (E) CLOSING BLADE OPERATOR MEANS RESPONSIVE TO THE DISENGAGEMENT OF SAID FIRST COUPLING MEANS FOR RELEASABLY MAINTAINING SAID CLOSISNG BLADE IN UNBLOCKING POSITION WHEREBY INCIDENT LIGHT PASSES THROUGH SAID APERTURE TO INITIATE EXPOSURE; (F) SAID OPERATOR MEANS BEING CONSTRUCTED AND ARRANGED SO THAT IT IS OPERABLE TO RELEASE SAID CLOSING BLADE; (G) MEANS MADE EFFECTIVE UPON RELEASE OF SAID CLOSING BLADE TO MOVE THE LATTER TO BLOCKING POSITION WHEREBY INCIDENT LIGHT IS PREVENTED FROM PASSING THROUGH SAID APERTURE TO TERMINATE EXPOSURE; AND (H) MEANS RESPONSIVE TO THE LEVEL OF SCENE BRIGHTNESS FOR AUTOMATICALLY OPEATING SAID OPERATOR MEANS AFTER A PRESELECTED AMOUNT OF LIGHT HAS PASSED THROUGH SAID APERTURE.