An optical apparatus is disclosed which has a scanner for scanning a predetermined area with a laser beam. The optical apparatus comprises: a laser source; a scanner having a scanning mirror for causing a laser beam generated by the laser source to scan; an angle sensor for sensing angles of the scanning mirror of the scanner; a fault detection block for determining whether the scanning mirror operates safely and normally based at least on angle information coming from the angle sensor; and a projection control block for controlling projection of the laser beam based on fault detection information coming from the fault detection block.