Edge portions of detection electrodes, such as a first linear electrode and a second linear electrode, that include the side surfaces of the detection electrodes and parts of surfaces of the detection electrodes, the surfaces continuing from the side surfaces and facing a photoconductive layer for recording, are covered with dielectrics. Further, surfaces of the detection electrodes and the dielectrics are coated with an anti-crystallization layer to prevent crystallization of a photoconductive layer for readout. At this time, the surfaces of the electrodes are smoothly covered with the dielectrics at angles .theta. of contact of 5 to 60 degrees so that no bump is present, thereby preventing generation of a crack in the anti-crystallization layer on the dielectrics and the electrodes. Accordingly, crystallization of the photoconductive layer for readout, which is induced by injection of charges from the edge portions of the detection electrodes or the like, is prevented.