Fabrication of spatial walk-off polarizing film exhibiting a large split angle by oblique silicon deposition

A spatial walk-off polarizing film with a large split angle was fabricated by use of the oblique deposition method. The film is composed of slanted needlelike microcolumns of a-Si that are separated by resultant fine voids. The polarization-splitting characteristics of the film were clearly observed. The maximum split angle at a wavelength of 1.55 microm was as large as 20 degrees , more than three times greater than those of existing polarizers such as those constructed of rutile and calcite.