A projector that includes a laser beam source that outputs a laser beam that is modulated based on an image signal and a screen on which the light beam is projected. The projector also includes a scanning unit that scans the laser beam within a predetermined surface and a scan monitoring unit that monitors scanning of the scanning unit and outputs a result of the monitoring. The projector further includes a beam light supply stopping unit that controls the laser beam source so as to stop output of the laser beam based on the result of monitoring output by the scan monitoring unit.