Abstract: In a device for projection on a dome with a plurality of projectors (50, 51, 54, 56) for displaying image contents on an at least partially spherical projection surface (52), wherein every projector (50, 51, 54, 56) is arranged in such a way that it illuminates at least a partial surface (56, 58) of the projection surface (52) with partial images, and there is provided for at least for one of the projectors (51, 54, 56) a light source (12) and a deflecting device (40) by which a light bundle (10) emitted from the light source (12) can be guided along the portion to be illuminated in order to display the image contents, the deflecting device (40) of the at least one projector (51, 54, 56) is constructed as a scanning device by which the light bundle can be guided in a plurality of lines with a plurality of picture points over the partial surface (56, 58) to be illuminated, and the light source (12) is connected to an intensity control (64) on the basis of which individual picture points can be illuminated for

Abstract: A device for generating a partial annular or an annular picture on a portion of a spherical projection surface by an annular mirror by which a light bundle generating this picture can be deflected onto the projection surface has a light source by which substantially parallel light bundles can be generated, a control unit for controlling the intensity of the light bundle, and a raster scanning device which is arranged in the light path between the annular mirror and the light source and which can raster scan the light bundle in two dimensions for the sequential illumination of picture points of the annular picture or partial annular picture.

Abstract: An improved projector for projecting fixed stars in planetaria increases the brightness and the brilliance of the projected sky by using fiber optical light guides. The device comprises at least one light source, one condenser, one star plate or templates and one lens, which projects the star plate template on the planetarium dome. A fiber optical light guide cable, the light-entry end of which faces the condenser and which consists of fiber optical light guides or fiber optical light guide bundles, is provided between the condenser and the associated star plate or template. The other end of the fiber optical light guide cable is split up into fiber optical light guides and/or fiber optical light guide bundles, the light-emergence ends of which are assigned to the locations on the star plate or template which are to be illuminated.

Abstract: This invention relates to an optical system for lantern slide projection, especially for star projectors in planetariums, with the aim of increasing the available light for the projection. The development consists in attaining an increase in brightness and brilliance of the image as well as a reduction in heat generation in the apparatus, through the application of resonator principles.The optical system comprises light sources, condensing lenses which reproduce the lamp filament, and the objective which reproduces the original. A resonator of high transparency which has highly reflective and/or totally reflective boundary surfaces is provided between condensing lens and objective. The boundary surface facing the condensing lens has a light-entrance opening comprising the lamp filament or the image of the lamp filament. The boundary surface lying opposite to that area preferably comprises the original to be projected.

Abstract: The invention relates to a projection device for star projections in planetaria in which a plurality of star projectors are provided in the wall of a substantially spherical housing in the center of which a light source is arranged. The projector mounts and/or the condenser lenses of the projectors preferably are polyhedrons. The sides of the polygonal condenser lenses have bevel edges via which they are contacting neighboring condenser, lens sides so that substantially no light losses are involved.

Abstract: The invention is in concern of an arrangement for producing artificial rainbows, particularly for use in planetaria, in which a bundle of light emitted from a light source and directed through an aperture upon a prism is dispersed by the latter and reflected at a cylindrical reflector. Due to the reflection at the cylindrical reflector the projected light bundle is of a rainbow shape, the radius thereof depends on the position of the cylindrical reflector relative to the prism.