Sony Corporation

Ryuji Shiono

Mitsuru Sato

Toshiaki Isogawa

Joichi Sato

Tsutomu Niimura

Masaaki Tsuruta

Minoru Morio

Tadashi Esashika

Tsutomu Nimura

A plurality of CCD image pickup devices are provided. When the multiplex exposure is executed, the exposure timings of the plurality of image pickup devices are set to different timings. The output signals of the plurality of image pickup devices of different timings are synchronized and synthesized, thereby forming a multiplexed signal.

Video camera

A video signal inverting circuit, wherein a pedestal level of an output signal is selectively changed between a posi-mode and a nega-mode. The pedestal level of the output video signal is set equal to the pedestal level of the posi-mode output video signal in the nega-mode in accordance with a nega-mode/posi-mode control signal. In spite of the nega-mode/posi-mode control signal, a level setting circuit for the posi-mode is used during horizontal blanking period in the nega-mode.

Video signal inverting circuit

A circuit for controlling the gain of an amplifier typically used in a video camera has a automatic gain control circuit to provide the camera output signal within predetermined limits and a switch to permit exclusion of the automatic gain control feature and the use of a manually variable gain control having a greater range and overlapping that of the automatic gain control to provide further flexibility to the user of the camera so that objects normally too bright or too dark to be accommodated within the range of the automatic gain control circuit can be recorded. Differential amplifiers operating in conjunction with current mirror circuits are provided in both the variable gain amplifier circuit and in the circuit that provides the gain control signal thereto to provide a gain control circuit that lends itself to integrated circuit fabrication.

Video camera gain control circuit

A circuit having a nonlinear response characteristic provides gamma compensation to a video luminance signal and matches any desired output response curve by selecting the number of diodes connected as series-connected circuits in the compensation circuit. The relationship among the various numbers of series-connected diodes is dependent upon having a current flowing into an output circuit which is the same as a current flowing out of a collector circuit of a differential amplifier, to which the input video luminance signal is applied, and through series-connected diode circuit. These currents are maintained equal by use of a current-mirror circuit, which provides an input current to an output transistor that has in its emitter circuit one of the series-connected diode circuits, and the compensated luminance signal flows in the collector circuit thereof. The differential amplifier is stabilized and balanced by a difference amplifier connected in feedback across the collector leads of the differential amplifier in conjunction with a pedestal clamping synchronization signal and a capacitor to provide a balancing signal at the base lead of the second transistor of the differential transistor amplifier.

Gamma compensating circuit

Apparatus is provided for automatically controlling or locking the iris aperture of a camera. The brightness level of a signal produced by the camera is detected and an automatic control circuit responds to this detected brightness level to energize an iris drive, thereby establishing the iris aperture. The actual size of that aperture is represented by an aperture signal. This aperture signal is used by a control signal generator to generate a control signal corresponding thereto. A selecting circuit is operable to select either an automatic control mode wherein the iris drive is energized by the detected brightness level of the signal produced by the camera, or an iris lock mode wherein the iris drive is energized to maintain the iris aperture at a fixed size irrespective of changes in that brightness level. An iris lock circuit responds to the selection of the iris lock mode for storing the control signal which is generated just prior to the selection of the iris lock mode, and compares the stored control signal to the aperture signal that is produced during the iris lock mode to energize the iris drive as a function of the difference therebetween. In the iris lock mode the automatic control circuitry is disabled. The iris aperture thus is fixed at a size determined by the stored control signal.

Growing community of inventors

Machida, Japan

Ryuji Shiono