According to one embodiment, an image sensor, which is a solid imaging device, includes a photoelectric conversion element array, a condensing optical element array, filter and reflector units, and a reflective unit. The reflective unit further reflects a light reflected by the filter and reflector units. The condensing optical element is arranged so that it contains a first photoelectric conversion element and a portion of a second or a third photoelectric conversion element, which are adjacent to the first photoelectric conversion element. The arrangement of the photoelectric conversion elements may comprise a cell. The reflective unit includes at least a first reflective surface and a second reflective surface. The first reflective surface is opposite to the filter and reflector units. The second reflective surface surrounds the filter and reflector units and the first reflective surface for each cell.