Patent ID: 6292220
Filing Date: 2001-09-18
Classification: H04N

Abstract:
An image sensing apparatus comprising:an image sensing device that includes a photoelectric conversion device section, vertical shift registers, and a horizontal shift register, where a signal charge storage period corresponding to an effective exposure time can be controlled by controlling a time interval when signal charges generated in the photoelectric conversion device section are integrated, and signal charges stored in the photoelectric conversion device section during the signal charge storage period can be read through the vertical shift registers and the horizontal shift register;an image sensing device driving circuit that supplies pulses for controlling the signal charge storage period to said image sensing device, pulses for driving the vertical shift registers, and pulses for driving the horizontal shift register;a light shading element for shading incident light to the photoelectric conversion device section of said image sensing device; anda light shading operation control element for controlling operation timing of said light shading element;said image sensing device driving circuit continuously performing discharge operation of unnecessary electric charges by driving the vertical shift registers and the horizontal shift register at a speed higher than that at a time of usual signal charge transfer driving from a beginning of a predetermined unit period to a time interval, including the signal charge storage period, in the predetermined unit period used for obtaining a signal expressing an image by supplying said respective pulses to the image sensing device, and stopping said discharge operation of unnecessary electric charges just before an endpoint of the signal charge storage period in said unit period,said light shading operation control element controlling the operation timing of said light shading element so that a substantial light shading state to the photoelectric conversion device section of said image sensing device may be established within said unit period after the endpoint of said signal charge storage period.