Provided is a radiation image detector, including: a substrate; a continued radiation conversion layer configured to convert radiation into visible light; an optical image detector on the substrate and between the radiation conversion layer and the substrate, wherein the optical image detector comprises an array of photosensitive pixels; a light-shielding structure located on a side of the plurality of photosensitive pixels facing away from the substrate, wherein the light-shielding structure has a plurality of openings to allow the visible light to reach the photosensitive pixels; and a light-collecting structure located between the radiation conversion layer and the light-shielding structure and comprising a plurality of convex lenses, wherein each convex lens has its optical axis perpendicular to the light-shielding structure and passing through one of the plurality of openings.