| 摘要 |
1460299 Polarizers FERRANTI Ltd 2 Oct 1974 [3 Oct 1973] 46200/73 Heading G2J A polarizer e.g. for a Q-switched laser comprises a prism substrate 10 and a plurality of (e.g. nine) thin films 11-15 which may be of two successively alternating materials as shown. The materials of the prism 10 and the films is such that light 30, which is incident at the interface between the prism 10 and the first film 11 at the Brewster angle, is refracted to be incident at every interface between the films at the Brewster angle. An output prism 16 is wrung to the last film 15. Prism 10 and films 12, 14 may be of silica; films 11, 13, 15 may be of cerium dioxide or zinc sulphide. The shapes of the prisms may be modified, Fig. 3, (not shown), so that the input and transmitted beams are oppositely directed and parallel. |
