JPS647777A - Solid-state image pickup device - Google Patents

Abstract

PURPOSE:To effectively display a function such as sensitivity control with simple circuit constitution by controlling such as the sensitivity corresponding the brightness etc., of an object by using two clock signals supplied for the control. CONSTITUTION:When a clock signal phi1 is supplied to a terminal 12, during the high level period of this signal phi1, a forward current is supplied to photodiodes 111-114, so that the diodes 111-114 are precharged. The discharge of these diodes 111-114 is executed in proportion to the amount of the incident light to the photodetective surfaces of the respective diodes 111-114, and the amounts of charges in the cathodes of the diodes 111-114 are controlled corresponding to said incident-light amount and the discharge time duration ts. When a clock signal phi2 inputted to a terminal 15 goes to a high level, the gates of clock clocked inverter 131-134 are opened corresponding to the period tphi2 said signal is at the high level, hence output signals corresponding to the respective cathode charge amounts are outputted from terminals 141-144.