Light projection device and light projection method

A light projection device according to the present invention is equipped with: a light projection unit provided with a light projection optical system for projecting light, the light projection unit projecting light of a prescribed shape to an object to which light is to be projected; a position detection unit for detecting the three-dimensional position of the object to which light is to be projected; a light projection direction change unit for changing the direction of the light projected by the light projection unit; a light projection direction control unit for making the light projection direction change unit change the direction of the projected light and having the light projected to the object to which light is to be projected at a position detected by the position detection unit; a shape calculation unit for calculating the shape of the light projected to the surface of the object to which light is to be projected at a position detected by the position detection unit; and a shape control unit for making the light projection unit project light of the shape calculated by the shape calculation unit.