Abstract

Polarizing optical elements are widely needed in modern optics. The combination of the beam shaping properties of a computer-generated hologram (CGH) with polarizing features provides a further step in integration of optical systems. We have developed a new technique to produce switchable polarizing CGHs. A microstructured glass substrate containing the hologram function is covered with a layer of NLC. The LC is oriented parallel to the substrate plane, and the lower refractive index of the LC is matched to the refractive index of the glass. Thus the hologram structure is invisible for one polarization state of light. The orientation of the LC may be changed by applying an electrical field between transparent electrodes on the substrate and the cover glass. In this case the refraction index is matched for all polarization directions. Finally, we obtain an element that serves as a CGH for one polarization direction, which does not effect the orthogonal one and which may be switched off via electrical control.

© 1992 Optical Society of America