Abstract: An apparatus projects luminous lines on an object by a laser beam and includes a laser beam generator wherein the laser beam has a width, a convex lens for limiting the width of the laser beam, and a reflector located at a position subsequent to the convex lens, wherein the reflector has a cylindrical reflecting surface adapted to allow the reflecting luminous lines to reflect unidirectionally at gradually decreasing angles with respect to the reflector. Thus, the laser beam is reflected at different points on the reflecting surface, at different angles, thereby forming sector-shaped continuous luminous lines on an object to be marked.

Abstract: An apparatus for projecting a laser beam linearly on an object, wherein a laser beam, once spread radially by a convex reflector or by a concave lens, is made to converge linearly by means of a cylindrical-concave reflector. The line of light obtained on an object by the apparatus disclosed herein is a constant and non-flickering one, being unlike that obtained by a conventional apparatus which reflects a laser beam by means of a rapidly rotating polygonal-prismatic mirror to give an apparent line of light on an object. The present invention can be embodied so as to give various patterns of lines by making the cylindrical-concave reflector have a plurality of cylindrical-concave reflective surfaces.