Abstract: An O-plate compensator is manufactured by dissolving a polyimide polymer material incorporating a plurality of bulky side-chain groups in a first solvent to form a first solution, applying the first solution to a substrate, evaporating the first solvent to form an alignment layer, buffing the alignment layer, dissolving a polymerizable liquid crystal material in a second solvent to form a second solution, applying the second solution to the alignment layer, evaporating the second solvent to form a thin film of polymerizable liquid crystal material (with a nematic phase, an alignment-layer interface having a liquid crystal pretilt angle of between approximately 25 and 65 degrees, and an air interface), adjusting the temperature of the thin film to obtain a uniform specified orientation of a director of the thin film, and polymerizing the thin film with ultraviolet radiation to achieve a liquid crystal pretilt angle of between approximately 25 and 65 degrees at the air interface.

Abstract: An electrical exciting circuit produces a plurality of oscillating electrical excitations, each at an independently controllable frequency. A set of drive electrodes are distributed in an array, and connected so that each receives a respective one of the excitations. A dual frequency liquid crystal (DFLC) material is arranged in the path of a coherent light beam and is disposed in proximity to the set of drive electrodes so as to receive electrical excitations. The DFLC has a dielectric coefficient which varies locally in relation to the frequency of the local electrical excitation received. The voltages and at least two frequencies of the excitations are controlled so as to produce a desired profile of the dielectric coefficient (for at least one polarization) and a corresponding optical phase delay profile for the coherent beam. Preferably, a novel reflective groundplane is included to improve optical reflective efficiency.

Abstract: An addressing scheme for use with current-driven emissive displays requires that an N-row by M-column array of pixels be divided into K segments of N/K rows each. One transistor-controlled current driver is provided for each column of pixels within a segment, and all of a segment's current drivers are connected to a respective gate address line. The array is addressed by dividing a frame time into N/K “sub-frame” times. During the first sub-frame time, the current drivers of each segment are turned on in sequence, and the first row of each segment addressed. The remaining rows are addressed in this manner during subsequent sub-frame times. The segmenting and addressing scheme reduces the duty ratio required to drive the array by a factor of K, and reduces the number of transistors required to drive the array by a factor of N/K, when compared with comparably-sized passive matrix and active matrix displays, respectively.

Abstract: The present invention relates to thin film retardation plates, such as cholesteric and A-plate compensators, for improving the viewing angle and contrast of liquid crystal displays. The A-plate is fabricated using a single substrate onto which a layer of polymerizable reactive mesogens (RMs) is solvent cast. Included in the RMs solution is an additive that migrates to the RM/air interface to lower the surface energy and generate an additive-rich surface layer, which in turn lowers the intrinsic tilt angle of the RMs at the air interface to between 25 degrees (25.degree.) and about zero degrees (0.degree.). The solvent is evaporated and the resulting film is polymerized in the liquid crystal phase to permanently orient the liquid crystal. The resulting film may be readily separated from the substrate and shaped into any desired pattern and combined to form novel compensators.