Abstract: To provide for uniformity of illumination across a film window, for example or super-8 mm film, the reflector has at least two contours whose generatrices follow conical sections which have a common optical axis in the direction of radiation emission, and which are so arranged that the sections are formed as sectors, with adjacent sectors having different contours. At least four sectors are used, and preferably the focal point of the generatrices are displaced relative to each other either in the reflector axis or on a parallel thereto, the conical section are identical, and two such conical sections are used, with surface areas at a ratio of between 4:6 or about even.

Abstract: To provide for essentially uniform illumination throughout the area, for mple the film window of a film or slide projector, the reflector has at least two contours which form a reflector system, each contour being rotation-symmetrical with respect to the optical axis of the total system. The generatrices of the contours follow conical sections. The reflector is divided into zonal regions, with successive zonal regions lying on different contours. For example, two conical contours can be used, the contour of one conical section being such that spot illumination results, and the contour of the other conical section being such that a saddle-tight illumination is obtained so that the overall light output throughout the window is essentially uniform (see the additive of FIGS. 3a and 3b, as shown in FIG. 3c).