METHOD FOR ADJUSTING FLOODLIGHT BEAM

An optical displacement sensor (10) which uses a Scheimpflug optical system comprises: a projection module (9) for emitting light to an object to be measured; a light-receiving portion (13) for receiving the reflected light on a light-receiving face when the light from the projection module (9) is reflected by the object to be measured; and a light-receiving lens (14) for focusing the reflected light on the light-receiving face, the light-receiving lens being positioned between the object to be measured and the light-receiving portion (13). A method for adjusting a projection beam adjusts the focal position of the light emitted from a light source (11) so that the size of an image formed on the light-receiving portion (13) is constant irrespective of the distance between the projection lens (12) constituting the projection module (9) and the object to be measured.