An image sensor includes a plurality of pixels arranged in matrix, and each pixel includes a first TFT having a first gate electrode and a second gate electrode that are arranged on a substrate, a second TFT, and a photoelectric conversion element that has a first electrode electrically connected to a first surface of an a-Si thin film and the second gate electrode of the first TFT and a second electrode connected to a second control line, and that is arranged above the first TFT so as to be superposed on the first TFT in an laminated direction. Provided is a gas barrier film that is positioned between the first and the second TFTs and the photoelectric conversion element and that prevents hydrogen from permeating into the first and the second TFTs, the first electrode and the second gate electrode are constructed by the same layer, and the gas barrier film is not provided with an aperture in each of the pixels.