Video file apparatus for displaying and storing data from plural documents in superposition

Claim 2

A video file apparatus comprising a synchronizing-signal generator circuit, a display device which operates in synchronism with synchronizing signals from said synchronizing signal generator circuit, a recirculating type of video-signal storage device synchronized with said signals from said synchronizingsignal generator circuit, a video-signal generating source synchronized with said signals from said synchronizing-signal generator circuit, a first gate for supplying a video signal from said video-signal storage device to said display device and back to said video-signal storage device, a second gate for supplying a video signal from said video-signal generating source to said display device and said video-signal storage device, and control means operated by said synchronizing-signal generator circuit for opening either one of said first and second gates at a time.

Claim 3

A video file apparatus according to claim 1, wherein said video-signal storage device comprises a magnetic recording medium, onto which outputs of said first and second gates are recorded.

Claim 4

A video file apparatus according to claim 1, wherein said control means includes timing means for generating timing signals representing predetermined periods of time designating positions at which said video signal from said video-signal generating source is to be displayed on said display device, said timing means counting the periods of time every time the synchronizing signals are received, whereby said first and second gates are controlled in dependence upon said periods of time so that one or the other of said first and second gates are opened at a time.

Claim 5

A video file apparatus comprising a synchronizing-signal generator circuit including a horizontal synchronizing-signal generator circuit and a vertical synchronizing-signal generator circuit, a display device operated in synchronism with synchronizing signals from said synchronizing-signal generator circuit, a recycling type of video-signal storage device synchronized with said synchronizing signals from said synchronizing-signal generator circuit, a video-signal generating source synchronized with said synchronizing signals from said synchronizing-signal generator circuit, first gate means for supplying a video signal from said video-signal storage device to said display device and back to said video-signal storage device, second gate means for supplying a video signal from said video-signal generating source to said display device and said video-signal storage device, first and second one-shot multivibrators responsive to a horizontal synchronizing signal from said horizontal synchronizing-signal generator circuit, a first flip-flop which is set by an output of said first one-shot multivibrator and which is reset by an output of said second one-shot multi-vibrator, third and fourth one-shot multivibrators which are set by a vertical synchronizing signal from said vertical synchronizing-signal generator circuit, a second flip-flop which is set by an output of said third one-shot multivibrator and which is reset by an output of said fourth one-shot multivibrator, an AND gate having respective inputs connected to the set outputs of said first and second flop-flops, means for opening said first gate means in response to an output of said AND gate, and means for opening said second gate means in response to an inverted output of said AND gate.

Claim 6

A video file apparatus comprising a synchronizing-signal generator circuit including a horizontal synchronizing-signal generator circuit and a vertical synchronizing-signal generator circuit, a display device operated in synchronism with synchronizing signals from said synchronizing-signal generator circuit, a recycling type of video-signal storage device synchronized with said synchronizing signals from said synchronizing-signal generator circuit, a video-signal generating source synchronized with said synchronizing signals from said synchronizing-signal generator circuit, first gate means for supplying a video signal from said video-signal storage device to said display device and back to said video-signal storage device, second gate means for supplying a video signal from said video-signal generating source to said display device and said video-signal storage device, first and second one-shot multivibrators responsive to a horizontal synchronizing signal from said horizontal synchronizing-signal generator circuit, a first flip-flop which is set by an output of said first one-shot multivibrator and which is reset by an output of said second one-shot multi-vibrator, third and fourth one-shot multivibrators which are set by a vertical synchronizing signal from said vertical synchronizing-signal generator circuit, a second flip-flop which is set by an output of said third one-shot multivibrator and which is reset by an output of said fourth one-shot multivibrator, an AND gate having respective inputs connected to the set outputs of said first and second flop-flops, means for opening said first gate means in response to an output of said AND gate, and means for opening said second gate means in response to an inverted output of said AND gate.