| abstract |
A method of making a light polarizing material having excellent polarization characteristics over wavelengths from the visible to the infrared (IR) region is disclosed. A smooth surface of an optical material, such as for example glass, plastic or IR transmitting material, is mounted in a vacuum enclosure and a vaporized material or metal is directed onto the surface. The metal may be gold, silver, copper or aluminum, for example, or any other material or combination thereof which is reflective at the wavelength to be polarized. As the deposition occurs on the surface, metal atoms are initially attached to sites on the surface with metal whiskers forming on the initial sites in the direction of the incident vaporized metal. The metal whiskers are grown with their long axis essentially parallel to the vaporized metal direction and essentially parallel to each other. Uniformity of the coating formed by the metal whiskers can be improved by subjecting the coated transparent surface to a second vaporized metal which produces second metal whiskers with their long axis essentially parallel to the second vaporized metal direction and the projections of said first and second metal whiskers onto the surface are essentially parallel to each other. The resulting polarizer material can be produced in sheet form or applied as a coating to optical elements. |