PURPOSE: To prevent the charge diffusion into potential wells of other picture elements by a method wherein an N type skin layer region is composed of a conduction base part and a plurality of fingers led out therefrom, and each finger is composed of picture element forming regions and connection parts joining adjacent picture element forming regions.

CONSTITUTION: The conduction base part 14 and a plurality of the fingers 11 led out from this conduction base part 14 are arranged in comb form, each finger 11 is isolated by a P type region, and further each finger 11 is formed into the pattern that a pluality of the picture element forming regions 12 are joined by the connection parts 13. It is for the purpose of keeping all the elements at the same potential that the picture element forming regions 12 are joined via the connection parts 13 in this manner. All of the other periphery of each picture element forming region contacts the P type region, except the part of joining to the connection part 13. In a photosensor constituted in such a manner, the most part of carriers diffused from the potneitial wells 10 and 10' of each picture element flows into the P type region and then extinguishes therein.