Polymer Enhanced Cholesteric Electro-Optical Devices

KSU.283

Abstract: We have developed an electro-optical device based on the spatially ordered polymer structure enhanced flexoelectro-optic effect utilizing uniform lying helix (ULH) of a short-pitched cholesteric liquid crystal.  The electric field induces the optic axis of ULH to rotate in a plane parallel to the surfaces of the cell.  The switching angle of the helical axis is a linear function of the applied field, at least for small fields and high frequency, which gives a well-controlled continuous grey scale.  By using a spatially ordered polymeric network localized on the substrate surfaces and new ChLC material, the device provides a high contrast for in-plane (flexoelectric) switching and phase (dielectric) modulation at high voltage. 

Applications:

• Amplitude modulators
• Light switches
• Phase-only spatial light modulators,
• Beam deflectors
• Flat panel displays
• Eyewear

Advantages: In addition to high contrast for in-plane switching and phase modulation at high voltage, this LC device also provides fast response times in the order of hundreds' microseconds for the IPS mode while continuous grey scale assures a very wide viewing angle.  Further, the response time is a few milliseconds for the phase modulation. 

Inventors:  Dr. L. C. Chien et al