| 摘要 |
PURPOSE:To eliminate a mechanical diaphragm mechanism, by controlling from outside a circuit to which the orinary adverse bias is applied to an adverse conduction type region and a semiconductor substrate, and the adverse bias voltage higher than the ordinary one, are applied. CONSTITUTION:For a charge tranfer device 42, the electric charge generated at a photoelectric converting region is swept away to a substrate in a period during which the adverse bias voltage applied between a substrate semiconductor and an adverse condution type region is set at V0 higher than the ordinary adverse vias voltage. While the signal charge is stored in a period T1 during which said adverse bias voltage is equal to the oridnary adverse bias voltage VS. A light volume setting part 46 sets this period T1, and the T1 is actually formed at a light volume control logical circuit 47 and with a pulse signal supplied from a logical circuit 43. A pulse voltage generating circuit 48 converts the voltage of a logical signal level into the adverse bias voltage and feeds the switching of adverse bias to the substrate semiconductor with binary levels V0 and VS. Thus the storage period T1 is obtained for the signal charge. This period T1 is controlled to adjust the incident light volume. |
