A 2.4 in. by 2.4 in. TFT LCD is presented with an embedded 60×60 array of a‐Si photo sensors, for use as a high performance touch‐enabled LCD with low cost. In the shadow mode the optical touch screen operates with finger or stylus input under ambient lighting conditions from 50 lux to 50 klux.

A series of CaSiO 3 :x%Tb 3+ , y%Sm 3+ compounds was synthesized by the conventional solid state reaction. X-ray diffraction, scanning electron microscopy, and energy dispersive x-ray spectroscopy investigations were conducted to determine crystal structure. The photoluminescence (PL) excitation spectrum of Tb 3+ and Sm 3+ doped compounds consists of a series of peaks corresponding to electronic transitions of Tb 3+ and Sm 3+ ions. The wavelength of 375 nm was optimal to excite the luminescence of Tb 3+ /Sm 3+ co-doped compounds. The PL emission spectrum consists of a set of intense lines at wavelengths of 415 nm, 436 nm, 457 nm, 488 nm, 543 nm, 586 nm, and 622 nm, corresponding to Tb 3+ electronic transitions of 5 D , respectively. The PL emission spectrum of the Sm 3+ doped compound has a series of three peaks located at wavelengths of 565 nm, 602 nm, and 648 nm, corresponding to the electronic transitions of Sm 3+ from 4 G 5/2 to 6 H 5/2 , 6 H 7/2 , and 6 H 9/2 , respectively. The energy level diagram was proposed. The lifetime measurements were conducted for all samples and energy transfer process was also examined by this way. The Commission Internationale de I'Eclairage chromaticity coordinates, correlated color temperature, and color rendering index of phosphors were determined and the results indicate that the obtained materials are optimal candidate for white LED applications.

An active matrix EL VGA display is reported with full grayscale using temporal voltage modulation of the phosphor. The exceptional brightness and dynamic range of the ZnS:Mn EL phosphor permits a new gray scale scheme. Digital gamma correction and an extended range of levels achieve 128 to 256 monotonic shades.

Abstract— Gallium codoping has been identified as an effective flux agent for SrS:Ce phosphor thin films. When rapid‐thermal‐annealed at temperatures above 750°C, the microstructure of sputtered SrS: Ce, Ga, F thin films underwent a transformation from columnar to spherulitic morphology. In addition, the crystal grain size increased by tenfold from 50 to 500 nm. Time‐resolved photoluminescent measurements on 810°C‐annealed SrS: Ce, Ga, F films showed decay times as long as 25 ns, indicating effective incorporation of Ce ions. As a result of crystallinity improvement, excellent electroluminescent performance, e.g., 60‐Hz L40 of 155 cd/m2, has been achieved in EL devices with 1.5‐μm‐thick SrS: Ce, Ga, F films. In addition, high luminous efficacy, e.g., e40 = 1.15 lm/W, was achieved in devices with a thin SiON buffer layer added between the SrS:Ce and a BaTa2O6 top insulator.

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