| 摘要 |
PURPOSE:To increase a dynamic range and to improve picture quality during incidence of high-level light by inputting pulses which synchronize with transfer pulses to the overflow gate of a CCd, and thus providing Knee characteristics to the photoelectric conversion of a solid-state image pickup element. CONSTITUTION:An overflow gate electrode 12 is applied with pulses (OFG pulse) which synchronize with both pulses (ODD pulse) for transferring charges corresponding to picture elements in odd-numbered lines and pulse (EVEN pulse) for transferring charges in even-numbered lines. The OFG pulses are synchronized to rise when the ODD pulses and EVEN pulses fall. Consequently, a barrier controlled by the gate electrode 12 rises from a position (b) to a position (a) to increase the chargeable amount of charges and during charge transfer, the barrier is lowered to the position (b) again. Therefore, even if high level light arrives to generate great charges, they are brought under complete control to obtain high-contrast picture quality. |
