According to the present invention, a stopper member lock mechanism is configured to lock a stopper member from rotating in a direction from a forward tilt location to a use location with respect to a shaft when the mirror assembly that is positioned in the forward tilt location is restored to the use location and to release the locked state of the stopper member when the mirror assembly is restored from the forward tilt location to the use location. As a result, it is capable of causing the mirror assembly to be precisely positioned in the use location without any positional shift when the mirror assembly that has rotated from the use location to the forward tilt location for the sake of buffering is rotated and restored from the forward tilt location to the use location.