A light-emitting section projects distance measurement light toward an object to be photographed. A switching section sequentially switches the projection direction of the distance measurement light projected from the light-emitting section. A first light-receiving section is arranged at a position separated from the light-emitting section by a first base length. The first light-receiving section receives a reflected light beam of the distance measurement light from the object and outputs a first signal corresponding to the incident position of the reflected light beam. The second light-receiving section receives a reflected light beam of the distance measurement light from the object and outputs a second signal corresponding to the incident position of the reflected light beam. An object distance calculating section calculates the object distance in accordance with first and second signals corresponding to the incident positions and output from the first and second light-receiving sections.