Profile projectors, used for checking the shape and dimensions of a wide variety of objects (pieces cut to shape, gears and pinions for small-sized mechanisms, screws, screw-taps, chasers, etc.), or for examining surfaces. In the majority of these projectors, light from a lamp is concentrated into a beam by a condenser before being directed on to the specimen, which is placed on a stage. The specimen is silhouetted in the beam which, after being reflected several times, is finally projected, by a set of prisms, on to a screen which is generally built in to the projector. Some of these projectors are fitted with an intermediate stage on which a standard part is placed.