Patent ID: 8614493

Claim:
A photosensor circuit, comprising: a photosensor element; and an amplifier element connected to the photosensor element, wherein the photosensor element comprises: a gate electrode disposed on an insulating substrate; a gate insulating film disposed so as to cover the gate electrode; a semiconductor layer provided on the gate insulating film so as to overlap the gate electrode; and a source electrode and a drain electrode provided on the semiconductor layer so as to overlap the gate electrode and so as to face each other, wherein the semiconductor layer has an intrinsic semiconductor layer in which the channel region is defined and an extrinsic semiconductor layer that is laminated on said intrinsic semiconductor layer such that said channel region is exposed, wherein the extrinsic semiconductor layer protrudes from the drain electrode on a side close to the channel region, wherein the amplifier element comprises: an amplifier gate electrode provided on the insulating substrate; the gate insulating film arranged to cover the amplifier gate electrode; an amplifier semiconductor layer disposed on the gate insulating film so as to overlap the amplifier gate electrode; and an amplifier source electrode and an amplifier drain electrode provided on the amplifier semiconductor layer so as to overlap the amplifier gate electrode and so as to face each other, wherein the amplifier semiconductor layer has an amplifier intrinsic semiconductor layer in which a channel region is defined and an amplifier extrinsic semiconductor layer that is laminated on said intrinsic semiconductor layer such that said channel region is exposed, and wherein edges of the amplifier extrinsic semiconductor layer on respective sides close to the channel region are respectively aligned with an edge of the amplifier source electrode and an edge of the amplifier drain electrode on the respective sides close to the channel region.