A lightweight cementitious composition containing from 22 to 90 volume percent of a cement composition and from 10 to 78 volume percent of particles having an average particle diameter of from 0. The optical sensor includes a light source in which a semiconductor laser having multiple light-emitting units is sealed with one resin member; a light source driving unit which causes the multiple light-emitting units to emit light; and at least one photodetector which detects a light amount of a light which is emitted from the multiple light-emitting units and is reflected from a subject. A select gate and a memory gate are spaced over the semiconductor substrate between the first and second sourcedrain regions.