Exposure detector device and a camera system with the exposure detector device

Claim 2

An exposure control system for a camera with an objective lens and a reflex mirror movable into and out of the path of light from the objective lens and whose exposure is adjusted by electromagnetic means, comprising photosensitive means disposed behind the movable mirror and in the path of light from an objective lens for responding to the brightness of a scene being photographed, control circuit means responsive to said photosensitive means and coupled to the electromagnetic means for adjusting the exposure on the basis of the light striking the photosensitive means, an electric power source coupled to said control circuit for actuating the control circuit, and switch means in said control circuit and responsive to movement of the movable mirror out of the path of light, for interrupting the operation of said control circuit.

Claim 3

A photographic system, comprising an objective lens, a reflex mirror movable into and out of the path of light through said objective lens, shutter control means, exposure adjusting means including electromagnetic means, photosensitive means disposed to receive light through the objective lens and through the mirror when it is placed in the path of light from the objective lens, a control circuit responsive to said photosensitive means and coupled to said electromagnetic means for adjusting the exposure of the system, and actuating switch means coupled with said control circuit, said switch means being responsive to movement of said mirror for interrupting the operation of said control circuit so as to prevent further adjustment of the exposure.

Claim 4

A photographic system, comprising an objective lens, a reflex mirror movable into and out of the path of light through said objective lens, shutter control means, exposure adjusting means including electromagnetic means, photosensitive means disposed to receive light through the objective lens and through the mirror when it is placed in the path of light from the objective lens, a control circuit responsive to said photosensitive means and coupled to said electromagnetic means for adjusting the exposure of the system, and actuating switch means coupled with said control circuit, said switch means being responsive to movement of said mirror for interrupting the operation of said control circuit so as to prevent further adjustment of the exposure.

Claim 5

A system as in claim 2, wherein said control circuit comprises a Wheatstone bridge, a comparator circuit responsive to said Wheatstone bridge, said Wheatstone bridge being coupled to said sensitive and responsive thereto, said electromagnetic means including a servo motor coupled to said comparator circuit and responsive to unbalance in the bridge.

Claim 6

A system as in claim 2, wherein said switching means is interlocked with said movable mirror and opened and closed by movement of said movable mirror.

Claim 7

A system as in claim 2, wherein said switching means includes delay means for delaying the response of the control circuit to said switching means.

Claim 8

A camera, comprising exposure adjusting means, regulation limit means for defining regulation limits on said exposure adjusting means, an electric motor coupled to said adjusting means for controlling the adjusting means, photosensitive means mounted for measuring the brightness of the scene to be photographed, comparison amplifying means connected to said photosensitive means and responsive thereto, said amplifying means being coupled to said electric motor for regulating the adjusting means, and limit switching means connected in said comparison amplifying means and responsive to said limit means for interrupting the output of said amplifying means.

Claim 9

A camera, comprising exposure adjusting means, regulation limit means for defining regulation limits on said exposure adjusting means, an electric motor coupled to said adjusting means for controlling the adjusting means, photosensitive means mounted for measuring the brightness of the scene to be photographed, comparison amplifying means connected to said photosensitive means and responsive thereto, said amplifying means being coupled to said electric motor for regulating the adjusting means, and limit switching means connected in said comparison amplifying means and responsive to said limit means for interrupting the output of said amplifying means.

Claim 10

An exposure control device for a camera, comprising photosensitive means for measuring the brightness of the scene, a control circuit responsive to said photosensitive means and having a driving circuit, exposure value control means, a servo motor connected with said driving circuit and coupled to said exposure value control means for regulating said control means, warning means having indication means coupled with said servo motor, said indication means defining upper and lower limit zones of scene brightness, said control circuit having a bridge circuit, said photosensitive means being connected in said bridge circuit, variable resistance means in said bridge circuit and coupled with said servo motor for varying the operation of said bridge circuit, said variable resistance means disclosing its resistance variation in response to the output of said photo resistance means and to form limit indications.

Claim 11

An exposure control device for a camera, comprising photosensitive means for measuring the brightness of the scene, a control circuit responsive to said photosensitive means and having a driving circuit, exposure value control means, a servo motor connected with said driving circuit and coupled to said exposure value control means for regulating said control means, warning means having indication means coupled with said servo motor, said indication means defining upper and lower limit zones of scene brightness, said control circuit having a bridge circuit, said photosensitive means being connected in said bridge circuit, variable resistance means in said bridge circuit and coupled with said servo motor for varying the operation of said bridge circuit, said variable resistance means disclosing its resistance variation in response to the output of said photo resistance means and to form limit indications.

Claim 12

An exposure control device as in claim 5, wherein said photosensitive means is a phototransistor.

Claim 13

A control system for controlling a load, a transistor bridge, output terminals at said transistor bridge, switch means in series with at least one of said output terminals, control means responsive to the output of the load for controlling at least one of said transistors in said bridge, said switch means being responsive to the operation of the load for disconnecting the load when the load operates in a range beyond the predetermined limit.

Claim 14

A control system for controlling a load, a transistor bridge, output terminals at said transistor bridge, switch means in series with at least one of said output terminals, control means responsive to the output of the load for controlling at least one of said transistors in said bridge, said switch means being responsive to the operation of the load for disconnecting the load when the load operates in a range beyond the predetermined limit.

Claim 15

A control system for automatic control of exposure, comprising a resistance bridge, said resistance bridge including a photosensitive element, differential amplifier means coupled to the output of said resistance bridge, a second differential amplifier means responsive to said first differential amplifier means and operative to invert the signals of said first differential amplifyer, a drive control circuit, said resistance bridge having a plurality of additional elements, said electromagnetic means being coupled to one of said elements for constraining said bridge toward balance in response to signals applied to said electromagnetic means.

Claim 16

A control system for automatic control of exposure, comprising a resistance bridge, said resistance bridge including a photosensitive element, differential amplifier means coupled to the output of said resistance bridge, a second differential amplifier means responsive to said first differential amplifier means and operative to invert the signals of said first differential amplifyer, a drive control circuit, said resistance bridge having a plurality of additional elements, said electromagnetic means being coupled to one of said elements for constraining said bridge toward balance in response to signals applied to said electromagnetic means.

Claim 17

A system as in claim 10, wherein said first differential amplifier means includes an input circuit, feed back means connected between said electromagnetic means and said input circuit, said feedback means including a capacitor and a resistor.