Patent ID: 8872120

Claim:
An imaging device comprising: a scintillator; and a plurality of pixel circuits that is arranged in a matrix with plural rows and plural columns and overlaps with the scintillator, the plurality of pixel circuits each comprising: a photodiode; a charge accumulation portion; a first transistor; a second transistor; and a third transistor, wherein one of a source and a drain of the first transistor is electrically connected to the photodiode, wherein the other of the source and the drain of the first transistor is electrically connected to the charge accumulation portion, wherein a gate of the second transistor is electrically connected to the charge accumulation portion, wherein one of a source and a drain of the second transistor is electrically connected to one of a source and a drain of the third transistor, wherein at least the first transistor includes a channel formation region including an oxide semiconductor, wherein an operation of resetting the charge accumulation portion is performed substantially at the same time in the plurality of pixel circuits, wherein an operation of accumulating an electrical charge by the photodiode is performed substantially at the same time in the plurality of pixel circuits, wherein an operation of reading a signal is sequentially performed for each row in the plurality of pixel circuits, and wherein gates of the third transistors of the pixel circuits in one row are electrically connected to a wiring.