METHOD OF CONTROLLING RESPONSE OF CCD IMAGE FORMATION DEVICE

摘要

PURPOSE: To improve the dynamic range of a CCD or its similar element. CONSTITUTION: A photo gate 10 stores electric charges for a predetermined exposure time. A sink region 21 to receive excess charges from the photo gate region 10 is placed and the transfer of the electric charge from the photo gate region 10 to the sink region 21 is controlled by a control gate 23 of a type used in general for integration control. A 2nd gated region is in existence to receive charges from the photo gate region 10 that transfers the charges. A level having an absolute value to transfer all charges whose level is higher than a prescribed charge clipping level in the photo gate region 10 to the sink region 21 is applied to the control gate 23 and the absolute value of the level is changed for the exposure time according to a predetermined function being a nonlinear function such as a logarithmic function.