Optical profile grinding machine SEIDEL amp; NAUMANN
This device consists of a frame 51 which carries a set of projection lenses 52, a mirror 53 and a plane or screen 54 upon which to project. It is an advantage to have the projection device provided with an attachment 55 for a magnifying glass. In order to have no light entering from the outside upon the projection device the latter is covered by a casing 56. The optical profile grinding