Browse Prior Art Database

Electrically Controlled Linear, Left-Circular, And Right-Circular Polarized Light Device

IP.com Disclosure Number: IPCOM000121029D
Original Publication Date: 1991-Jul-01
Included in the Prior Art Database: 2005-Apr-03
Document File: 2 page(s) / 66K

Publishing Venue

IBM

Related People

Ong, HL: AUTHOR

Abstract

Disclosed is a light polarization device, using a combination of a cholesteric liquid crystal (CLC) film and a nematic liquid crystal (NLC) film, where the polarization of the output light can be made to be either linearly, left-circularly, or right-circularly polarization from an unpolarized incident light. By changing the voltage applied across the NLC film, the polarization of the output light can be varied to give one of the three states.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 60% of the total text.

Electrically Controlled Linear, Left-Circular, And Right-Circular
Polarized Light Device

      Disclosed is a light polarization device, using a combination
of a cholesteric liquid crystal (CLC) film and a nematic liquid
crystal (NLC) film, where the polarization of the output light can be
made to be either linearly, left-circularly, or right-circularly
polarization from an unpolarized incident light.  By changing the
voltage applied across the NLC film, the polarization of the output
light can be varied to give one of the three states.

      The figure shows the present disclosed light polarizing device,
in which a combination of CLC film and a NLC film is used to control
the polarization of the transmitted or reflected light.

      In the present disclosed device, the polarization selection is
made by the NLC film, which acts as a variable retardation film.  The
NLC film is made by a homogeneous-oriented NLC film, or a
homeotrophic- oriented NLC film.  The NLC film can also have a
constant pretilt angle or even an inhomogeneous tilt orientation.
The thickness of the NLC film can always be made so that a selected
retardation occurs at a selected applied voltage. We let dNLC be the
retardation of the NLC ELECTRICALLY CONTROLLED LINEAR, LEFT-CIRCULAR,
AND RIGHT-CIRCULAR POLARIZED LIGHT DEVICE  -  Continued film.  The
polarization of the transmitted light is right-circular for dNLC = 0,
left-circular for dNLC = g/2, linear for dNLC = g/4.  The thickness
o...