Abstract: An illumination assembly for an optical viewing device that includes an optical subassembly for viewing an illuminated object plane. The illumination assembly includes a base member having an imaging window formed therethrough, a plurality of LEDs fixed to the base member in a plane substantially coplanar with the imaging window for projecting light upwardly away from the base member, and a non-mirrored reflector for redirecting light emitted from the LEDs back through the imaging window toward the object plane to illuminate the object plane. The non-mirrored reflector is positioned so as to house the LEDs, and includes a central aperture for providing optical communication between the illuminated object plane and the optical subassembly.

Abstract: A video equipped endoscope having a solid state image sensor mounted in the distal end of an insertion tube that is connected to a video processor. The active diathermal lead of an electrosurgical generator also passes through the insertion tube in close proximity with the video components. To protect the video from the radio frequency diathermy signals, the image sensor and the video and service leads are both placed in a conductive shield that is electrically connected to the chassis of the video processor. The chassis is, in turn, electrically connected to the RF ground reference point on the electrosurgical generator whereby any radio frequency alternating current flowing through the stray capacitance between the active diathermal lead and the conductive sheath of the insertion tube as well as the conductive shield over the image sensor and service leads or RF current or voltage potentials induced by electrostatic or electromagnetic coupling between the active lead and these components are returned.

Abstract: An interface module for a video endoscopic system that permits the insertion tube to be connected to and disconnected from a video processor quickly and easily whereby sterilizing the tube is simplified and the substitution of one tube for another is greatly facilitated. The connector module interfaces the various video and other electric connections and also interfaces a fiber optic bundle connection and a fluid supply connection between the processor and insertion tube. A solid state imaging device is located at the distal end of the insertion tube, and this device is driven by signals received from the processor and transmits video signals back to the processor. The interface module contains circuitry that accepts standard input signals from the processor for driving the imaging device, and this circuitry includes means for adjusting the input signals so that they are compatible with the particular imaging device in the tube.

Abstract: Apparatus for controlling the video signal level of a color endoscope to prevent the picture from blooming as the viewing head of the instrument is moved toward and away from a confined target. Circuit means are provided for automatically controlling both the amplified gain of the signal and the intensity of the illumination used to light the target during a series of color imaging sequences so that the color balance of the system is not disturbed.

Abstract: A camera includes a photographic film having a given film speed which decreases when the film is exposed to light which varies from a given illumination level. A camera shutter is controlled by a timing circuit adapted to produce an exposure which is adjusted to compensate for the decreased film speed.

Abstract: A video processing system for a television receiver is shown. The video processing system includes a gain controlled stage through which a video signal is coupled. The gain of the stage is controlled to provide contrast control of the video signal. The video signal is also applied to an aperture correction circuit which develops an aperture correction signal including pre-shoot and over-shoot transient responses. The aperture correction signal is also coupled through the gain controlled stage so that it is amplified or attenuated by the same amount as the video signal. The output of the gain controlled stage is coupled to an output stage. A portion of the video signal from the output stage is compared to a reference voltage in a black level control circuit. The control signal from the black level control circuit is applied to the output stage to control the black level of the video signal. The disclosed video processing system is further adapted for fabrication in integrated circuit form.

Abstract: A DC controlled amplifier is used to control the chrominance gain, and hence the color saturation, of a television receiver. The voltage on the wiper of a Color Control variable resistor and the output of an Automatic Color Level (ACL) detector are combined in a summing network to provide a DC voltage to the controlled amplifier. The ACL detector develops an output voltage that tends to maintain the peak-to-peak chrominance signal, and therefore the color saturation, at or below a threshold level. A control tracking circuit varies the threshold level in accordance with the voltage on the wiper of the color control variable resistor, thereby maintaining the dynamic range of the Automatic Color Level Control System relatively independent of the setting of the Color Control.

Abstract: A video processing system for a television receiver is shown. The video processing system includes a gain controlled stage through which a video signal is coupled. The gain of the stage is controlled to provide contrast control of the video signal. The gain of the gain controlled stage is also automatically controlled in response to a beam current feedback to provide automatic contrast or white level control. In addition, the automatic control circuit provides beam circuit limiting by reducing the gain of the gain controlled stage to minimum in response to beam currents in excess of a threshold. An aperture correction signal is also coupled through the gain controlled stage so that it is amplified or attenuated by the same amount as the video signal. The output of the gain controlled stage is coupled to an output stage where the black level of the video signal is controlled by a black level control circuit. The disclosed video processing system is further adapted for fabrication in integrated circuit form.

Abstract: A video processing system for a television receiver is shown. The video processing system includes a gain controlled stage through which a video signal is coupled. The gain of the stage is controlled to provide contrast control of the video signal. The video signal is also applied to an aperture correction circuit which develops an aperture correction signal including pre-shoot and over-shoot transient responses. The aperture correction signal is also coupled through the gain controlled stage so that it is amplified or attenuated by the same amount as the video signal. The output of the gain controlled stage is coupled to an output stage where the black level of the video signal is controlled by a black level control circuit. The disclosed video processing system is further adapted for fabrication in integrated circuit form.

Abstract: A video processing system for a television receiver is shown. The video processing system includes a gain controlled stage through which a video signal is coupled. The gain of the stage is controlled to provide contrast control of the video signal. The video signal is also applied to an aperture correction circuit which develops an aperture correction signal including a pre-shoot transient responses. The aperture correction signal is also coupled through the gain controlled stage so that it is amplified or attenuated by the same amount as the video signal. An automatic peaking control circuit receives the pre-shoot and over-shoot signals to generate an automatic control signal to control the gain of the aperture correction circuit. A tracking control circuit causes the automatic peaking control circuit to accurately track the setting of an adjustable control which controls the gain of the aperture correction circuit.

Abstract: A protection circuit for a television receiver which disables the television receiver by disabling the horizontal deflection circuit in response to fault conditions is shown. The protection circuit detects excessive current drain by a low voltage supply, excessive current drain by a high voltage supply, and excessive high voltage. In response to any one of these fault conditions, the horizontal deflection circuit is disabled.

Abstract: A cathode ray tube raster in a television receiver is blanked for selected channels chosen to receive audio information by a bias circuit coupled to a video signal source connected to a cathode ray tube wherein the bias circuit provides a given bias potential to the cathode ray tube when a modulated picture carrier signal is detected and a different bias potential blanking the raster of the cathode ray tube when an unmodulated picture carrier signal is detected.