Farbprojektionsverfahren und -vorrichtung von durch Modulation optischer Lichtventile entstandenen Bildern

摘要

Modulation by optical valves (Vb, Vv, Vr) of three beams originating from a main (W) or auxiliary (W') primary beam of depolarised and collimated light, is done by means of two secondary beams of white light (Wp, Ws; W'p, W's) which are mutually perpendicular, linearly polarised and mutually perpendicular. The undesirable colour components are deleted so as to constitute the three colour beams constituting the colour image. By virtue of the invention, the geometric and spectral quality of the image is independent of the main or auxiliary primary beam, and the image is as powerful as that obtained by the conventional projection method. The auxiliary beam may serve as a backup or may be adapted for a night projection.