Kohji Tada

Reflection Mode Polymer-Dispersed Liquid Crystal Light Valve

This paper describes the procedure for fabrication of a reflection-mode polymer-dispersed liquid crystal light valve (PDLCLV) consisting of a polymer-dispersed liquid crystal film, a diamondlike carbon film, a dielectric mirror, a Bi12SiO20 photoconductive crystal plate, and transparent electrode films. The many advantages of the PDLCLV include the lack of need for polarizers, high optical transmittance, high-speed response and ease of fabrication. The performance of the device as evaluated experimentally is as follows: optical transmittance 72%; extinction ratio 178/1; limiting resolution 34 lp/mm; and rise/decay times 14/15 ms. These values are suitable for the image converter of an optically addressed projection display. It has also been found that the resolution increases as the frequency of the AC voltage driving the PDLCLV decreases.

Polymer-dispersed liquid crystal light valves for projection display

We describe the polymer-dispersed liquid crystal light valve (PDLCLV) using a polymer-dispersed liquid crystal (PDLC) film and a Bi 12 SiO 20 (BSO) photoconductive crystal. The PDLCLV has many features suitable for large screen displays, such as no polarizer requirement, a high transmittance (72 to 78%) and high extinction ratio (146:1 to 178:1) in the entire visible wavelength, short rise/decay times (3/5 to 14/15 ms), and a high resolution (34 lp/mm). We discuss the light scattering and modulation characteristics of the PDLC film; photoconductive characteristics of the BSO crystal; and the design, fabrication method, and optical input/output characteristics of the PDLCLV. We also describe the configuration and image display characteristics of a monochrome projection-type display consisting of the PDLCLV as an image converter, an active matrix liquid crystal panel with thin film transistors as an image source, and a 1-kW xenon arc lamp as a reading light source.

Liquid-phase epitaxial growth of bismuth silicon oxide single-crystal film: a new optically activated optical switch.

A single-crystalline double-layered structure of a pure (80-microm)/doped (39-microm)/pure Bi(12)SiO(20) (BSO) substrate was grown for the first time by a new liquid-phase epitaxial growth to form an optical waveguide. The waveguide layer is BSO doped with CaCO(3) (0.1 wt. %) and Ga(2)O(3) (0.197 wt. %) and has a refractive index 0.07% higher than the substrate. The optical absorption coefficients were decreased by more than 1 order of magnitude by doping with the elements Ca and Ga. The high-sensitive photoconductivity of pure BSO was also reduced. Using these unique properties, we have constructed a new type of optically controlled planar optical switch.

Superconducting Phases with Single Tl-O Layer Structure Preparation: (Tl, Pb)Can-1Ba2CunO2n+3 (n=2, 3, 4, 5, 6)

Single Tl-O layer structures with two to six Cu-O layers, (Tl, Pb)Can-1Ba2CunO2n+3 (n=2, 3, 4, 5, 6), are prepared, and the superconducting properties of their phases are investigated. The c-lattice constants of the observed phases obey the c-axis rule of c=6.38+3.19n for single Tl-O layer structures. With an increase in Cu-O layers, the superconducting transition temperature, determined from electrical resistivity-temperature dependency and DC susceptibility, rises, reaching a maximum value of 121 K at n=4, and then falls with a further increase of the number of Cu-O layers from four to six.

Polymer-dispersed liquid-crystal light valves for projection display application

This paper describes the polymer-dispersed liquid crystal light valve (PDLCLV) using a polymer-dispersed liquid crystal (PDLC) film and a photoconductive crystal. Bi12SiO20 (BSO) and its application to projection displays. The PDLCLV has many features suitable for large screen displays, including no requirement of polarizers, high transmittance, and high-speed response. We discuss the light scattering and modulation characteristics of the PDLC film, photoconductive characteristics of the BSO crystal, and the design, fabrication and optical input/output characteristics of the PDLCLV. We also describe the configuration of a monochrome projection display consisting of the PDLCLV as an image converter and a liquid crystal panel with thin film transistors as an image source and its image display characteristics.