Ccd imager with overflow drain

Abstract

A CCD solid state imaging device has an overflow mechanism to discharge excess electric charges at the sensor section. An overflow level can be stabilized without adjustment. The CCD solid state imaging device includes an overflow barrier region for determining an amount of electric charges handled by a sensor section, and an overflow drain region for discharging excess electric charges at the sensor section adjacent to the sensor section. An intermediate region having the same potential as that of the sensor portion is provided between the overflow barrier region and the overflow drain region. Also, a CCD solid state imaging device includes linear sensors provided in a plurality of lines and vertical transfer registers provided at end of the linear sensors in the charge transfer direction of the horizontal transfer registers. When signal charges are overflowed in a part of the horizontal transfer register, signals of all pixels can be avoided from being destroyed. In a CCD solid state imaging device having linear sensors arranged in a plurality of lines, and vertical transfer registers provided at ends of the linear sensors in the charge transfer direction of the horizontal transfer registers, there is formed a limit region for limiting electric charges to a predetermined amount before electric charges are transferred from the horizontal transfer register to the vertical transfer register.