HIGH SELECTIVITY THIN FILM POLARIZER
 Inventors: Hugh L. Garvin, Malibu; Douglas A.
Pinnow, Pacific Palisades, both of
 Assignee: Hughes Aircraft Company, Culver City, Calif.
 Appl. No.: 54,361
 Filed: Jul. 2, 1979
 Int. CI.' G02B 5/30; B05D 3/00
 U.S. CI 350/320; 156/643;
219/121 EK; 219/121 LJ; 350/370; 350/395;
427/38; 427/43.1; 427/163
 Field of Search 350/147, 152, 395, 320;
343/909; 219/121LJ, 121 EK; 427/38, 43.1,
 References Cited
U.S. PATENT DOCUMENTS
3,271,771 9/1966 Hannan et al 343/909
Auton, J. P., "Infrared Transmission Polarizers by Photolithography", App. Optics, 6-1967, pp. 1023-1027.
Harvey, A. F., "Coherent Light", Wiley Interscience, 19 0, pp. 227-234.
Primary Examiner—-William H. Punter
Attorney, Agent, or Firm—Robert M. Wallace; William
A thin film polarizer for dividing electromagnetic energy into two mutually orthogonal components with a high degree of selectivity. A plurality of wire grids having an interelement spacing of less than one wavelength is supported by a substrate of electrically insulative material. The substrate is invisible to the wavelength of the polarized electromagnetic energy. The planar wire grids are substantially parallel and spaced less than one wavelength therebetween to achieve an efficient and compact thin film polarizer. The process of this invention for forming the plurality of wire grids comprises photolithographically defining each grid layer by the interference pattern of at least two coherent beams such as laser beams, one forming step being required for each grid, an anti-reflective layer being inserted between adjacent grid layers.
4 Claims, 9 Drawing Figures