Optical design for single-mode and single-cell gap transflective liquid crystal displays.

Generally, for transflective liquid crystal displays with different modes and different cell gaps between the refractive and transmissive parts, precise process control to pattern the electrode and match the cell gaps may reduce the yield and thus, require high cost. This paper proposes a simple transflective liquid crystal display with a single-mode and single-cell thickness without a patterned electrode to achieve better productivity. The proposed transflective liquid crystal display consists of three half-wave retardation films, two quarter-wave retardation films, and an LC layer, whose optical performance was confirmed by both simulation and experiment.

Reducing temperature dependence of the output energy of a quasi-continuous wave diode-pumped Nd:YAG laser.

It is demonstrated by numerical modeling that spectrally dispersed compound pumping diodes and low-loss pumping chamber reduced the temperature dependence of the output energy of quasi-continuous wave diode-pumped Nd:YAG lasers considerably. Several compound diodes with different spectral profiles were tested for pumping. The laser energy was calculated as a function of diode temperature from -30°C to 60°C.

Reflective color display using thermochromic pigments.

A reflective thermochromic display fabricated by a very simple method using three kinds of thermochromic pigments is produced and its thermo-optical characteristics are investigated. The display exhibits maximum red, green, and blue reflectances of 38%, 30%, and 35%, respectively. The reflective display cell shows continuous gray color with changing temperature, which is crucial for multicolor displays.

Zenithal alignment of liquid crystal on homeotropic polyimide film irradiated by ion beam.

We investigate the pretilt characteristics of a nematic liquid crystal [LC] in terms of ion beam exposure conditions on the homeotropic polyimide alignment layer. The pretilt angle of LCs in the case of high-energy ion beam treatment was decreased considerably almost the same to that of the homogenous alignment layer though we used homeotropic polyimide film at first. Increasing irradiating energy, we could control the pretilt from 90° to 1° with several steps.

Single-cell gap-transflective liquid crystal display using two optical modes of a bistable liquid crystal.

We present a single-cell gap-transflective liquid crystal display (LCD) characterized by a π cell having bulk-type liquid crystal (LC) bistability and an optical film configuration. The π cell has two stable states, which are a twisted and a nontwisted LC state. We used the twisted LC state for the reflective part connected with nonpatterned electrodes, producing a vertical field in the proposed transflective LCD.

Determination of actual surface azimuthal anchoring strength using a wedge-shaped liquid crystal cell.

We present a method that determines the actual surface azimuthal anchoring strength based on the torque balance. It is found by an optical technique of measuring simultaneously the cell thicknesses and twist angles at two regions of a wedge-type liquid crystal cell whose cell thickness varies continuously between different positions in the cell.

Diode-pumped 100-W green Nd:YAG rod laser.

We developed a diode-pumped high-average-power Nd:YAG green laser. By use of a monolithic diffusive reflector having three slits and a rod with low doping concentration, uniform distribution of excited Nd ions could be achieved. Uniform distribution in the rod reduced thermal birefringence.