Patent attributes
A method to overcome a disadvantage that the signal charges decrease depending upon the storage time in a photo-electric conversion unit of a solid-state image pickup device. At the moment t2 when a prescribed exposure time (t1−t2) passes, the incident light is cut off by a cut off means such as a mechanical shutter of an interlace solid-state image pickup device. Then, at the time t3, a voltage VBsub is applied to N− semiconductor substrate 107 to raise up the potential barrier Δφ of the vertical OFD for the signal charges, whereby the leakage of the signal charges due to the self-induced drift, or the thermal diffusion is suppressed. Then, signal charges are read out from the odd lines at the time t4, and signal charges are read out from the even lines at the time t5.
