Solid state image sensor

Claim 1

A solid state image sensor comprising: a plurality of row lines; a plurality of column lines; a plurality of pixels, each pixel comprising a normally-on type static induction transistor having gate, source and drain and a control transistor having a source-drain passage connected to said gate of said static induction transistor, said gate storing photocarriers induced by incident light, said static induction transistors and control transistors of pixels being formed on a same substrate and being arranged at cross points of the row and column lines; means for scanning the pixels to readout an image signal by selectively making conductive the static induction transistors; and means for selectively making conductive one or more control transistors of pixels which are not selected by the scanning means, and for discharging through the source-drain passages of the respective control transistors of non-selected pixels exceess amounts of stored photocarriers over a pinch-off voltage of the static induction transistors of said non-selected pixels; wherein adjacent four pixels are formed symmetrically with respect to a center region whereby first sources and drains of four control transistors of said four pixels are constituted by a common region formed in said center region and each of the others of sources and drains of four control transistors are formed integrally with each of the gates of respective static induction transistors of each of said four pixels.