An image processor by way of a transistor array in which a plurality of transistors are formed on a substrate comprising a plurality of polysilicon thin-film transistors using a first semiconductor layer composed of polysilicon formed on the substrate and functional devices having a plurality of amorphous silicon thin-film transistors using a second semiconductor layer composed of amorphous silicon which are formed in an upper layer more superior than the first semiconductor layer. The polysilicon thin-film transistors and functional devices include a plurality of electrode layers composed of a conductor layer, for instance, the functional devices at least of any one of the electrode layers are formed in the same layer as any one the electrode layers of the polysilicon thin-film transistors.