Illuminating system for projection purposes

摘要

An illuminating system for projection purposes consists of a light source (Q), a lens condenser (K) (in particular a bipartite one), and an e.g., tripartite projection lens (O). The calculation of the aspherical surfaces (A2, A3) of the condenser (K) includes the imaging characteristics of the projection lens (O) and the emission characteristics of the light source (Q), in order thereby to obtain an image plane which is illuminated uniformly or in accordance with a predetermined characteristic. The calculation of the characteristics of the illuminating system, in particular the aspherical surface of the condenser is not subject to any mathematical constraint, e.g. due to the stipulation of a specific polynomial; rather it is exclusively the stipulation of the light distribution in the image field which is decisive for the contour of said surface. The calculation of the spherical surfaces is based on interpolation with the aid of a cubic spline function.