Efficient polarization converter for projection displays.

In the waveguiding limit, a twisted nematic liquid crystal cell behaves as an achromatic polarization rotator. We propose and demonstrate the application of such a polarization rotator to convert unpolarized light into linearly polarized light with almost 100% efficiency. This polarization converter has a 2:1 aspect ratio, which is close to the 16:9 ratio for modern televisions. It can be used therefore in a projection display with polarization-dependent light valves such as a liquid crystal light valve. Both transmittive and reflective light valves can be used. The temperature dependence of the achromatic polarization rotator is also studied.

[1]  J A Dobrowolski,et al.  Visible broadband, wide-angle,thin-film multilayer polarizing beam splitter. , 1996, Applied optics.

[2]  Shin-Tson Wu,et al.  Infrared Properties Of Nematic Liquid Crystals: An Overview , 1987 .

[3]  M. Barnik,et al.  Large Aperture Polarized Light Source and Novel Liquid Crystal Display Operating Modes , 1990 .

[4]  M. Schadt,et al.  Influence of solutes on material constants of liquid crystals and on electro‐optical properties of twisted nematic displays , 1976 .

[5]  J. Fünfschilling,et al.  New Liquid Crystal Polarized Color Projection Principle , 1990 .

[6]  Brigitte Loiseaux,et al.  Polarized light source for LCD projection , 1995 .

[7]  Shin‐Tson Wu,et al.  Mixed‐mode twisted nematic liquid crystal cells for reflective displays , 1996 .

[8]  E. Duda,et al.  Modified MacNeille cube polarizer for a wide angular field. , 1989, Applied optics.

[9]  W. C. Yip,et al.  AMLCD on a Silicon Substrate with Integrated Digital Data Driver , 1995 .

[10]  H. Kwok.  Parameter space representation of liquid crystal display operating modes , 1996 .

[11]  W. H. Jeu,et al.  Thermotropic Liquid Crystals, Fundamentals , 1988 .

[12]  U Efron,et al.  Optimal operation temperature of liquid crystal modulators. , 1987, Applied optics.

[13]  M. Schadt,et al.  Physical properties of new liquid-crystal mixtures and electrooptical performance in twisted nematic displays , 1978, IEEE Transactions on Electron Devices.

[14]  T. Uchida,et al.  A new achromatic reflective STN‐LCD with one polarizer and one retardation film , 1995 .

[15]  G. W. Gray.  Thermotropic liquid crystals , 1987 .

[16]  S. Shikama,et al.  A polarization-transforming optics for a high-luminance LCD projector , 1991 .