The feasibility of conventional polarization-selective substrate-mode holograms is usually limited by the finite refractive index modulation strength. Therefore, in this study, a novel design of polarization selective element with a large diffraction angle is proposed based on the coupled-wave theory. The polarization selective element for 632.8nm is fabricated with VRP-M silver-halide recording material. The diffraction efficiencies of s- and p- components are 83% and 5%, and the calculated extinction ratios are 5.58 and 275, respectively. Polarization selective elements fabricated by the proposed method have all the merits of conventional substrate-mode hologram but not limited by the finite refractive index modulation of common recording materials.
In this study, a simple method for measuring the small displacements is presented. When a circularly polarized
heterodyne light beam reflected from a mirror is incident into a hemi-spherical prism and is reflected at the base of the
prism. Then the reflected light beam passes through an analyzer for interference. With properly chosen azimuth angles of
transmission axis of the analyzer, the phase difference between <i>s</i>- and <i>p</i>- polarized light is sensitive to the incident angle
near the internal reflection polarization angle. The phase difference can be accurately measured with the heterodyne
interferometry. The small displacement of the mirror causes a small variation of incident angle and a phase change.
Therefore, substituting the phase difference into special derived equations; the small displacement can be determined.
The proposed method has advantages of common-path configuration and heterodyne interferometry.