IMAGE SENSOR AND PIXEL READING METHOD USED THIS IMAGE SENSOR

An image sensor and a pixel reading method used this image sensor, in which the accuracy of a black level can be increased by that an optical black region being the black level reference of signals is read every horizontal line at a local or random access mode, are provided. And also the structure of a camera system used this image sensor can be simplified is provided. The image sensor is a MOS type image sensor composed of a pixel array region and an optical black region disposed at the one end in the pixel array region. And the MOS type image sensor provides a mode selector that selects the local access or random access mode or a frame access mode. When the local access or random access mode is activated, the image sensor decides a pixel reading region in the pixel array region. The image sensor reads information of one or more pixels having a designated horizontal line address in the pixel reading region every horizontal line address. After this, the MOS type image sensor reads information of one or more pixels having the same designated horizontal line address in the optical black region.