Solid state image sensor.

摘要

An image sensor comprises an array of photo-transistors (1) each of which has a collector region, an emitter region and a base region. A first switch (4) is connected to the base region of each photo-transistor. A second switch (2) is connected to the base region of each photo-transistor (1) and is operative after the respective photo-transistor (1) has discharged electric charge accumulated therein during exposure thereof to incident light, thereby to set a potential level of the base region thereof to a given substantially constant value thereby to re-set the corresponding photo-transistor.