Exposure control device for electronic photographing apparatus

Claim 1

An electronic photographing system comprising: an objective lens system for receiving incident light from an object; first solid state image sensor means for receiving said incident light through said objective lens system for producing an image signal usable to measure an exposure, and also usable to form a television image signal; second solid state image sensor means for receiving said incident light through said objective lens system for producing an image signal for still picture recording; shutter means for blocking the incident light to said second solid state image sensor means at a predetermined timing; first driving means for driving said first solid state image sensor means so as to enable said first solid state image sensor means to issue the image signal; second driving means for driving said second solid state image sensor means and including means for generating a plurality of driving pulses including a first driving pulse for reading out an image signal corresponding to a first field and a second driving pulse for reading out an image signal corresponding to a second field; shutter driving means for driving said shutter means for controlling an exposure time during which said second solid state image sensor means responds to the image signal issued from said first solid state image sensor means, said shutter driving means including an exposure control signal generator means for providing an exposure signal to determine a proper exposure time on the basis of an output signal from said first image sensor means, and said shutter driving means providing a shutter drive pulse based on said exposure control signal in synchronism with said second driving pulse, said shutter drive pulse having a pulse width corresponding to the exposure time; gate circuit means for controlling passage of said first and second driving pulse to said second solid state image sensor means so as to inhibit said first and second driving pulses while said shutter drive pulse is present and also to inhibit said second driving pulse anticipant of said first driving pulse immediately after extinction of the shutter drive pulse; synchronizing signal generator means for generating pulses including first synchronizing pulses and second synchronizing pulses respectively supplied to said first driving means and to said second driving means; recording means responsive to operation of a shutter release for recording an image data signal on a recording medium, said image date signal corresponding to the image signal issued from a selected one of said first solid state image sensor means and said second solid state image sensor means; and means coupled to said synchronizing signal generator means for driving said recording medium in synchronism with the operation of at least one of said first driving means and said second driving means under synchronization control based on an output from said synchronizing signal generator means.