| 摘要 |
The invention relates to a copying lamp for exposing, particularly for graphics purposes, materials that are sensitive to UV radiation and are arranged on a flat copying surface, having a metal halide burner as radiation source, a shutter arranged upstream thereof, and a reflector which preferably consists of high-purity aluminium. The arc of the radiation source (9) is located between the focal point (14) and the apex of the approximately cylindrically shaped reflector (16), and the reflector (16) is - seen in the cross-section perpendicular to the longitudinal extent of the radiation source (9) (XZ central plane) - is constructed as a parabolic or circular segment having a secant (18, 19) adjoining each side relative to an axis (17) of symmetry in such a way that the reflected radiation of one reflector half impinges on the respectively corresponding half of the copying surface located there below, the angle of incidence of each reflected beam (angle between beam and normal to the reflecting surface) at the copying surface (20) being always equal to or less than the angle of incidence of each direct beam on the copying surface (20). The surface normals of the reflector surfaces (20a-d) above the XZ central plane relative to the surface normals (22) of the reflector surfaces (24a-d) extend divergently at an acute angle below the XZ central plane. <IMAGE>
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