Through-the-viewfinder light shading device

Claim 1

In a single lens reflex camera having an automatic exposure control system that is primarily responsive to light entering through the objective lens but that is subject to an error caused by light entering through the eyepiece of the camera viewfinder, the combination comprising a member movable into and out of a position where it blocks light entering through the eyepiece so that the exposure control system is rendered immune from said error; an energizable electromagnet including an armature; means including said armature for moving the member; a battery; electric current carrying conductors for conducting current for energizing the electromagnet; a switch having a normally open position and being closable to a complete circuit through which current supplied by the battery flows through the conductors to energize the electromagnet and a self-timer mechanism operative to sequentially close the switch and then return it to its normal position so that light measuring by the exposure control system is accomplished with the member blocking the error-causing light.

Claim 3

A device for cutting off light entering through an eye lens into a photographic camera of through-the-lens light measuring type having therein an electronic shutter, the device comprising an electromagnet; a member serving to cut off light entering through the eye lens, the member being arranged so that advancement and retracting of said member into and out of a position at which said member is effective for shading is effected by a driving operation of the electromagnet; controllable means for energizing the electromagnet, the controllable means including electric current carrying conductors for conducting current for energizing the electromagnet, and a switch closable to complete a circuit through which current flows through the conductors to energize the electromagnet; and a self-timer mechanism for controlling the controllable means to effect energization of the electromagnet in a series of operations consisting of the first half stage of starting and the second half stage of starting and thereby light measuring is accomplished with the light entering through the eye lens being cut off.

Claim 4

A device for cutting off light entering through an eye lens into a photographic camera of through-the-lens light measuring type having therein an electronic shutter, the device comprising an electromagnet; a member serving to cut off light entering through the eye lens, the member being arranged so that advancement and retracting of said member into and out of a position at which said member is effective for shading is effected by a driving operation of the electromagnet; controllable means for energizing the electromagnet, the controllable means including electric current carrying conductors for conducting current for energizing the electromagnet, and a switch closable to complete a circuit through which current flows through the conductors to energize the electromagnet; and a self-timer mechanism for controlling the controllable means to effect energization of the electromagnet in a series of operations consisting of the first half stage of starting and the second half stage of starting and thereby light measuring is accomplished with the light entering through the eye lens being cut off.