Solid state image pick-up device and its charge transfer method

Abstract

A solid-state image pick-up device has transfer gates and storage capacitive elements with smaller capacitance than that of a vertical transfer lines between the vertical transfer lines to which signal charge is transferred through the operation of a signal charge transfer circuit containing the vertical shift register and switch elements, and a horizontal shift register for receiving the signal charge. The horizontal shift register is of the charge coupling type. The horizontal shift register has unit elements two times the vertical transfer lines. An optical signal and the other charge than the optical signal charge are stored in the adjacent unit elements and then the other charge than the optical charge is outputted to the other portion than a signal output portion. A charge transfer method for the solid state image pick-up device comprises a first step of injecting bias charge from the storage capacitive elements to the vertical transfer lines, a second step for transferring a changed amount of the charge on the vertical transfer line and the bias charge to the storage capacitive element and a third step for transferring only the changed amount of the charge to the horizontal shift register.