bluuebunny/crossref_metadata_2025 huggingface dataset:
Moving‐image enhancement on AMLCDs
Authors: Bitzakidis Stefanos
Published: May 2006

Abstract— One of the important advantages of AMLCDs over the conventional CRT is the complete absence of large‐area flicker. This is the direct result of the temporal behavior of LCDs. LCD pixels display the information placed on them continuously during the display period. This “time persistence” is also found to be one of the reasons why moving images displayed on AMLCDs appear to suffer from speed‐dependent spatial blurring. A novel technique is proposed which compensates the video information for the speed‐dependent blurring. The technique improves the quality of moving images on AMLCDs using an appropriate spatial filtering process.
Combining passive‐ and active‐matrix addressing of LCDs
Authors: Kuijk K. E.
Published: May 2006

Abstract—A combination of passive‐ and active‐matrix addressing is proposed by dividing the ITO columns of a passive‐matrix LCD in parts, thus only covering a group of rows. The ITO parts are connected to metal columns via TFTs. This leads to a significantly smaller number of TFTs, as compared to an active‐matrix LCD. The proposed system may either be driven as a switched passive matrix (SPM) with a low multiplexing factor, or as a multiplexed active matrix (MAM) by holding the voltages. The number of row connections may be decreased by connecting the corresponding ITO rows of a number of groups. Both row‐at‐a‐time addressing and multiple‐row selection with orthonormal waveforms may be used for both driving methods.
Analog gray scale in antiferroelectric liquid crystals
Authors: Quentel Simone , Rodrigo Covadonga , Otón José Manuel
Published: May 2006

Abstract— The electro‐optic behavior of antiferroelectric liquid‐crystal displays (LCDs) has been investigated. By choosing proper addressing waveforms, multiplex‐compatible analog gray‐scale driving schemes have been found. The schemes have been tested at different temperatures for assessing their use in real displays. A temperature range where both the addressing voltage and transmission slope are constant have been determined. A wider temperature range where the addressing voltage is shifted, but the transmission slope is still constant, has been found as well. These ranges include room temperature and warmer temperatures achieved by backlit displays.
Pixel‐defect‐tolerant design based on visibility for TFT‐LCDs
Authors: Nakai Yutaka , Akiyama Masahiko , Ikeda Mitsushi , Suzuki Kouji
Published: May 2006

Abstract— The repair of pixel defects on TFT‐LCDs, which is generally carried out with laser processing or by adopting a redundant structure, is very effective for high‐yield production. However, repair may result in abnormal pixel performance, usually due to the asymmetry of the applied pixel voltage. In this study, based on consideration of the dependence of the threshold contrast on the background luminance, the authors are able to determine the visibility of a repaired pixel. As a result, good agreement between measured and calculated visibility was obtained. Based on these results, we have proposed a new pixel design rule which enables complete repair of pixel defects that cannot be detected by the human eye. This design can also suppress the reduction of the aperture for TFT‐LCD panels. Furthermore, we demonstrate a new redundant structure which reduces the change in pixel performance after repair to a lower level than is attainable with any other reported technique.
The Fourier scope: An optical instrument for measuring LCD viewing‐angle characteristics
Authors: Saleh Bahaa E. A. , Lu Kanghua
Published: May 2006

Abstract—An optical system called the Fourier scope is an improved alternative to the conoscopic microscope for instant measurement of LCD viewing‐angle patterns. The Fourier scope includes a hand‐held detecting head for measuring on‐line flat‐panel LCDs, and allows non‐critical measurement distances ranging from millimeters to centimeters, a viewing‐angle range of ±70°, the use of true color patterns describing color fidelity or dispersion effects, and approximately linear viewing‐angle coordinates.
High‐definition TV rear projector using LCD panels
Authors: Yokozawa Minori
Published: May 2006

Abstract— A compact 55‐in. HDTV rear projector with 55‐cm depth has been developed by using three 4.55‐in. poly‐Si TFT‐LCDs of 960 × 1439 pixels with TFTs and 960 gate drivers included. The clear displayed picture without moiré has a luminance of 101 cd/m2, contrast ratio of 70:1, and horizontal viewing angle of 80°.
Current crowding and phosphor efficacy in ac thin‐film electroluminescent display devices
Authors: Singh Vijay P. , Bhaskaran Suraj , McClure John C.
Published: May 2006

Abstract— The variation of luminance with transferred charge in ZnS:Mn ac thin‐film electroluminescent (ACTFEL) display devices was analyzed to determine the roles played by the preferred current paths (filamentary conduction) and manganese clustering in limiting the phosphor efficiency. Luminance‐charge (L‐Q) characteristics were measured in ZnS:Mn ACTFEL devices of varying Mn concentrations. L‐Q characteristics showed a reduction in slope at higher values of Q. Also, the value of Q where the slope changed varied with the Mn/Zn ratio. These effects were attributed to the existence of preferred current paths in the phosphor layer where hot‐electron flow clustered.
The electronic document display: A 6.3‐million‐pixel AMLCD
Authors: Martin Russel A. , Chuang T. , Steemers Hugo , Fulks R. , Stuber Susan , Lee David D. , Young Michael Y. T. , Ho Jackson , Nguyen M. , Meuli William P. , Fiske Thomas , Bruce Richard H. , Da Costa Victor , Kowalski Robert P. , Lewis Alan , Turner William , Thompson Malcolm J. , Tilton Mary , Silverstein Louis D.
Published: May 2006

Abstract— This paper describes 6.3‐million‐pixel active‐matrix displays in monochrome and color (1.6 million color groups) with a diagonal dimension of 33 cm (13 in.), first discussed by Martin et al. in 1993. These displays have the largest number of pixels of any AMLCDs thus far reported. The monochrome display is intended for office‐automation applications where there is a requirement for electronically controlled image reproduction with characteristics similar to those of a conventional laser print. This display achieves the resolution, luminance, and viewing angle required for these applications through a binary driving scheme.
Polymer‐stabilized STN devices
Authors: Fredley David S. , Li Jianlin , Quinn Brian M. , Bos Philip J.
Published: May 2006

Abstract— The addition of polymers, along with standard parameters such as d/p, elastic constants, and twist state, can be considered another parameter in the optimization of an STN display. A low percentage of a polymer dopant has shown to eliminate stripe formation in 270° STN devices, as well as providing steeper thresholds and wider viewing angles in optimized displays. Data will be presented to show the effect of polymer concentration and curing conditions on STN devices.
A completely self‐aligned TFT‐array process using five masks
Authors: Kakkad Ramesh , Jinnai Toshihide , Miura Yasunori , Honjo Masuji , Shibusawa Makoto , Ibaraki Nobuki , Obara Takashi , Matsunaka Shigeki , Ito Hitoshi
Published: May 2006

Abstract— In this paper we present a five‐mask process to make completely self‐aligned inverted‐staggered amorphous‐silicon TFTs. The mask‐count reduction from a conventional seven‐mask process was accomplished by simultaneous patterning of pixel electrodes and signal lines and by the use of back‐side laser annealing. A mobility value close to 1 cm2/V‐s was obtained for TFTs fabricated using this process.
The birth and early childhood of active matrix — A personal memoir
Authors: Brody T. Peter
Published: May 2006

Abstract— The genesis and evolution of the concept of active matrix and its reduction to practice at Westinghouse Labs in the early '70s is recounted from a personal viewpoint by the author, who was manager of the thin‐film projects at the time. The story is continued beyond Westinghouse's abandonment of the project to the formation in 1981 of Panelvision, the first AMLCD company, and ends in 1985 when Panelvision was sold and Japanese companies assumed their present dominant position in the market. A postscript expresses views of the author on the future of active‐matrix displays.
Multi‐field driving method for reducing LCD power consumption
Authors: Okumura Haruhiko , Itoh Goh , Suzuki Kouhei , Suzuki Kouji , Sasaki Minoru
Published: May 2006

Abstract—We have developed a multi‐field driving method for TFT‐LCDs in which a displayed image was divided into at least three interlaced sub‐field images where visible flicker did not occur as the image refresh rate was decreased. This method made it possible not only to reduce driving‐power consumption in the case of still images to less than half, compared to that of conventional methods, but also to ensure that large‐area flicker and line flicker were invisible to the human eye.
The present and future prospects of electroluminescent phosphors
Authors: Kobayashi Hiroshi , Tanaka Shosaku
Published: May 2006

Abstract— Significant progress in the performance and commercialization of color thin‐film electroluminescent (EL) displays has been achieved. This is due to the remarkable progress made in the performance of existing EL phosphors, development of new phosphor materials, and design of new EL phosphor structures. The physics of materials and luminescent centers of current EL phosphors (ZnS:Mn2+, ZnS:RE3+, SrS:Ce3+, and SrGa2S4:Ce3+) are reviewed. As potential EL phosphors, metal oxides, yttrium oxides, oxysulfides, fluorides, and mixed‐crystal‐based phosphors are discussed. Multilayered and superlattice‐structured EL phosphors are also discussed. The basic physics of the materials, host lattices, and luminescent centers is important in the development of novel EL phosphors.
New green phosphors for plasma displays
Authors: Yocom Niel , Meltzer R. S. , Jang K. W. , Grimm M.
Published: May 2006

Abstract— Quantum efficiencies in the vacuum ultraviolet, chromaticities, and decay times of a number of highly efficient green phosphors for plasma‐display applications are compared. It is shown that the Tb3+‐activated phosphates offer improved quantum efficiencies relative to those of the standard plasma‐display phosphor, Zn2SiO4:Mn, for applications where 10‐ms decay times are acceptable. For applications requiring a very fast response, a new Eu2+‐activated strontium aluminate is found to provide an efficient green phosphor whose efficiency is about 40% of the best phosphate but with a luminescence decay time of only 5 μs.
Hydrothermal hexaaluminate phosphors
Authors: Roy Rustum , Ravichandran D. , White William B.
Published: May 2006

Abstract— Two members of the hexaaluminate family of phosphors, BaMg2Al16O27:Eu2+ and MgAl11O17.5:Ce3+,Tb3+, were synthesized at low temperatures by hydrothermal reaction at 800°C and 50–70 MPa water pressure. Well‐crystallized single‐phase products were obtained with a particle size in the range of 1–2 μm. Good luminescence intensities were obtained under near‐UV excitation, but luminescence intensities under vacuum UV (plasma display) excitation are less than observed for phosphors synthesized by high‐temperature processing. These compounds appear to be a more ordered stacking arrangement and are crystallographically different phases from those produced when the same compositions are fired at high temperatures.
Transparent Y2O2S:Eu3+ phosphor thin films grown by reactive evaporation and their luminescent properties
Authors: Daud Alias , Futaki Hisanori , Ohmi Koutoku , Tanaka Shosaku , Kobayashi Hiroshi
Published: May 2006

Abstract— Transparent Y2O2S:Eu3+ phosphor thin films have been grown by a reactive evaporation method. Y metal vaporized by electron‐beam irradiation was allowed to react with SO2 gas molecules. Eu was simultaneously supplied from a resistively heated crucible containing EuCl3 powder. By employing a heated W filament and an ac plasma cell to excite (crack) the SO2 molecules, Y2O2S:Eu3+ thin films and thin films containing both Y2O3 and Y2O2S phases which showed intense red photoluminescence were obtained. These results suggest that the films obtained are crystallized and Eu3+ ions substitute for Y ions in the Y2O3 and Y2O2S lattices and hence form luminescent centers.
The Influence of Zr4+ and Ca2+ on the luminescence efficiency of Y2O3:Eu3+
Authors: Evans D. R. , Raukas M. , Van Schaik W. , Happek U. , Dennis W. M. , Yen W. M. , Basun S.
Published: May 2006

Abstract— Y2O3:Eu3+ has been extensively investigated as a red phosphor for fluorescent lamps and color displays. In particular, there have recently been several studies examining the effect of impurities on the luminescence efficiency for Y2O3:Eu3+ under UV excitation. In this work we investigate the effects of codoping Y2O3:Eu3+ with Ca2+ and Zr4+ on the emission produced by cathode‐ray excitation. Specifically, we have measured the relative efficiency, fluorescent lifetimes, and fluorescent spectra under cathode‐ray excitation and compare these results to those previously observed under UV excitation.
Improvement on the linearity of blue phosphor: Evaluation of hexagonal ZnS:Ag,Al
Authors: Toyama Hisashi , Matsukiyo Hidetsugu , Shiiki Masatoshi , Komatsu Masaaki
Published: May 2006

Abstract— ZnS:Ag,Al phosphors were prepared in an H2S flow without using flux at various temperatures. A cubic structure (a zinc‐blende structure) was obtained for the sample prepared at 900°C, and a hexagonal structure (a wurzite structure) was obtained at 1050–1200°C. The life was improved simply with increasing preparation temperature. The luminous efficacy and the current coefficient had their optimum temperature at 1050°C. They showed similar tendencies related to the preparation temperature. The diffuse reflectance also showed the similar tendency of the preparation temperature dependence. The thermoluminescence measurement showed that the traps at a depths of 1.3 eV (observed below 1050°C) and 1.15 eV (observed above 1050°C) disappeared at a preparation temperature of 1050°C.
A study of the variables affecting adhesion strength of electrophoretically deposited phosphors
Authors: Russ Benjamin E. , Talbot Jan B. , Sluzky Esther
Published: May 2006

Abstract— Electrophoretic deposition of phosphor particles onto substrates is used in the manufacturing of screens for advanced display applications. The effects of deposition conditions on the adhesive properties of electrophoretically deposited phosphor coatings were investigated. The adhesion was measured with a gas‐jet tester which utilizes a short pulse of nitrogen gas to remove phosphor particles from the substrate. The percentage of phosphor particles remaining on the substrate after the test was used as a qualitative measure of adhesion strength, whereas the average diameter of the “ring” of particles removed was correlated to a quantitative measure of the adhesion strength. It was found that the adhesion strength was independent of applied voltage, conductive coating on the substrate, deposit thickness, phosphor concentration, and post‐deposition treatment with water and MgO top coating. The adhesion strength was enhanced by post‐deposition baking (at 425°C) and increasing the water content of the deposition bath. The adhesion strength is also dependent upon the type of phosphor deposited and exposure of the deposits to humidity.
Synthesis and characterization of metal‐oxide nanocrystals prepared by CO2‐laser‐heated vaporization/condensation
Authors: Tissue Brian M. , Eilers Hergen
Published: May 2006

Abstract— This paper describes the preparation and characterization of nanocrystalline particles of ZnO, Eu2O3, and Eu3+:Y2O3 by CW CO2 laser vaporization and gas‐phase condensation of metal oxide ceramics. Particle diameters range from 5–280 nm for ZnO and 2–30 nm for Eu2O3, for a variety of preparation conditions. ZnO forms in the usual room‐temperature hexagonal crystal structure but Eu2O3 and Y2O3 crystallize in a metastable monoclinic phase. The optical spectra of 14‐nm Eu2O3 particles have the same sharp lines as furnace‐heated monoclinic Eu2O3. The spectra of 5‐nm Eu2O3 particles show the sharp lines superimposed on broad and shifted bands. The spectra of 12‐nm Eu3+:Y2O3 particles show two phases that are attributed to slightly disordered Eu2O3 and crystalline Eu3+:Y2O3. The spectra of 5‐nm Eu3+:Y2O3 particles show only broad bands that are similar to the spectra of 5‐nm Eu2O3.
Phosphor degradation under electron excitation with varying anode voltage
Authors: Bechtel Helmut , Czarnojan Wolfram , Haase Markus , Wadow Dieter
Published: May 2006

Abstract— A model for the variation of phosphor Coulomb degradation with anode voltage is presented, using the volume energy density as scaling parameter. With reference to the bulk phosphor degradation at 30 kV, Coulomb degradation down to 2 kV has been calculated. A result of this model is that the degradation at a given charge dose increases with decreasing anode voltage. Considering the high charge doses accumulated in low‐voltage displays operated at CRT brightness, only phosphors which are stable at 30 kV are expected to be applicable at low voltages. The predicted phosphor degradation at 4 kV is experimentally confirmed for oxide, silicate, and oxy‐sulfide phosphors. For zinc sulfides the degradation measured at 4 kV is much faster than predicted, pointing to considerable contributions of surface‐related effects.
Viewing distance and the perceived size of simulator imagery
Authors: Wetzel Paul A. , Pierce Byron J. , Geri George A.
Published: May 2006

Abstract— The apparent size of a simple stimulus was measured in order to quantify the effect of viewing distance on the perception of real (i.e., uncollimated) CRT imagery. The viewing distances tested were those used in several operational, real‐image flight simulators. All identifiable distance cues to object distance except for ocular vergence and accommodation were eliminated. For six observers, it was found that perceived size changed significantly with changes in stimulus distance between 800 cm and either 61 cm or 94 cm, or vice versa. The data are consistent with the changes in perceived size reported for other stimuli and viewing conditions, and suggest that simulator imagery presented within about 1 m of the observer must be magnified by 15–25% in order to provide size cues consistent with those provided by objects located at optical infinity. For two of the six observers, measured vergence levels were consistent with the viewing distances tested, whereas measured accommodation levels were less than expected. Thus, at least for these two observers, it appears that differences in the level of ocular vergence were primarily responsible for the observed changes in perceived size.
Development of 17‐in. “pure flat” color‐monitor tube
Authors: Taki A. , Arimoto N. , Okamoto T. , Ueda Y.
Published: May 2006

Abstract—A perfectly flat‐face color‐monitor tube with 0.24‐mm‐pitch stripe screen has been developed. The anisotropically tensioned mask with slot holes has made it possible. The bonded front glass plate with conductive A/R (anti‐reflection) coating satisfies TCO regulation and the high performance new DQ‐DAF electron gun has been introduced. This tube is combined with newly developed deflection yoke which maintains self‐convergence function for multi‐scanning application in the display monitors. For the first time, the system includes three criteria for the next‐generation color‐monitor tube: perfectly flat screen, stripe phosphor arrangement, and multi‐scanning function.
Development of yoke for “pure flat” 17‐in. CRT
Authors: Honda M. , Shimada K. , Yonetani I. , Ose T. , Arimoto N. , Shimada K.
Published: May 2006

Abstract— A novel DY design for the perfectly flat‐screen “Pure Flat Tube” has been developed. The unique PSM (petal‐shaped multi‐section) saddle coils provide N/S pincushion‐distortion‐free while maintaining self‐converging function for a multi‐scanning application in display monitors. In addition, new techniques for reducing DY temperature rise and VLMF radiation have been introduced.
An overview of organic electroluminescent materials and devices
Authors: Tang C. W.
Published: May 2006

Abstract— Issues critical to the development of highly efficient and stable electroluminescent devices based on vapor‐deposited thin organic films are described.
Optical systems for high‐luminance LC rear projection
Authors: Hamada H.
Published: May 2006

Abstract— A front projector and rear‐projection TV's for home entertainment have been brought to market at affordable prices by virtue of a mosaic color‐filterless single‐LCD projection system with tilted dichroic mirrors and microlens array. In this paper, the optical throughput of LC projectors is discussed with respect to spectral domain and “geometrical extend,” which is the product of display area and acceptance angle of the optical system including LCD(s).
Colorimetry performance of a high‐brightness DMD™‐based optical system
Authors: Fielding R. G. , Burton M. L. , Bartlett T. A.
Published: May 2006

Abstract— A description of the colorimetric properties of a Rank Brimar high‐brightness large‐screen video projector using a Texas Instruments Digital Micromirror Device™ (DMD)‐based system is presented. Dichroic surfaces are used to split white light into three primary colors which illuminate three separate DMDs. The modulated reflected light is then recombined through dichroics to produce a projected image in full color. Employing common dichroics for both the illuminating and reflecting beams provides not only economy in cost and space, but enhanced colorimetry performance due to the differing angles between illuminating and imaging beams incident upon the dichroic surfaces.
a‐Si self‐scanned 2.2‐in. EDTV projection LC light valve
Authors: Lebrun H. , Szydlo N. , Maurice F. , Borel T. , Stewart R. G. , Weisbrod S. , Huq R.
Published: May 2006

Abstract— We developed a 560 × 960‐pixel 2.2‐in. AMLCD with a 46 × 50‐μm pitch and amorphous‐silicon integrated drivers. This display is intended to be used as a light valve in high‐efficiency projection systems for consumer TV. It operates at a line rate of 32 kHz in progressive scanning and an equivalent video rate of 36 MHz. It can stand high illumination intensities and achieves a good aperture ratio with a high contrast.
Miniature FLC/CMOS color‐sequential display systems
Authors: Banas D. , Chase H. , Cunningham J. , Handschy M. A. , Malzbender R. , Meadows M. R. , Ward D.
Published: May 2006

Abstract— We describe a novel active‐matrix liquid‐crystal‐display technology that drives a ferroelectric‐liquid‐crystal (FLC) light‐modulating layer with a reflective, crystalline‐silicon CMOS backplane. We have realized two prototypes: a 256 × 256 display with 15‐μm pixel pitch, and a 1280 × 1024 display with 7.6‐μm pixel pitch. Using sequential color and “digital” time‐domain gray scale, we display images with up to 15 bits of color at frame rates up to 76 Hz. The resulting displays are useful for both projection and “virtual” display applications, and have outstanding cost, light efficiency, and image quality characteristics.
Automotive head‐up display using liquid‐crystal‐on‐silicon displays
Authors: Schuck M. H. , McKnight D. J. , Johnson K. M.
Published: May 2006

Abstract— We are constructing a head‐up display for an automotive application based on a liquid‐crystal‐on‐silicon microdisplay. We shall describe the application driving the device development, the display device, and the technology enhancements implemented for this application.
Wide‐viewing‐angle 13.3‐in. XGA displays with in‐plane switching mode of nematic LCs addressed by TFTs
Authors: Kondo K. , Kinugawa K. , Konishi N. , Kawakami H.
Published: May 2006

Abstract— We have developed a 13.3‐in. TFT‐LCD employing a new, wide‐viewing‐angle “super” TFT technology utilizing the in‐plane switching mode of nematic liquid crystals. The new TFT‐LCD has XGA resolution (1024 × RGB × 768 pixels), displaying 262,144 colors, providing vertical and horizontal viewing angles of 140°. This is far wider than that of a conventional TFT display, which is restricted to about 40° vertically and 90° horizontally.
Spectra Vue™: A new system to enhance the viewing angle of LCDs
Authors: Lowe D. , Chin T. , Credelle T. L. , Tezucar O. , Hairston N. , Wilson J. , Bingaman K.
Published: May 2006

Abstract— SpectraVue™, a new system to enhance liquid‐crystal‐display (LCD) viewing‐angle performance, has been developed. The addition of SpectraVue components to any LCD greatly expands the usable viewing cone, resulting in significant improvements in contrast ratio, color purity, and gray‐scale fidelity. Contrast and color inversions are also completely eliminated at all angles. With SpectraVue‐modified LCDs, contrast ratios of greater than 75:1 have been demonstrated at ±45° (horizontal and vertical) on an active‐matrix LCD and greater than 10:1 on STN‐LCDs over the same range. The operating principles of the key components of this new design will be described.
Reflective color LCDs based on H‐PDLC and PSCT technologies
Authors: Crawford G. P. , Fiske T. G. , Silverstein L. D.
Published: May 2006

Abstract— In this paper we determine the visual parameters required for effective, full‐color reflective displays. We analytically examine a number of contemporary liquid crystal (LC) technologies and associated optical configurations which hold promise for achieving reflective color displays. We conclude that reflective displays based on holographically formed polymer‐dispersed liquid crystals (H‐PDLCs) and polymer‐stabilized cholesteric‐texture liquid crystals (PSCT) are the most viable color‐capable reflective technologies to date.
A six‐mask TFT‐LCD process using copper‐gate metallurgy
Authors: Fryer P. M. , Colgan E. , Galligan E. , Graham W. , Horton R. , Hunt D. , Jenkins L. , John R. , Koke P. , Kuo Y. , Latzko K. , Libsch F. , Lien A. , Nywening R. , Polastre R. , Rothwell M. E. , Wilson J. , Wisnieff R. , Wright S.
Published: May 2006

Abstract— A novel reduced mask process is used to fabricate high‐resolution high‐aperture‐ratio 10.5‐in. SXGA (1280 × 1024) displays. The process uses copper gate‐metallurgy with redundancy, without the need for extra processing steps. The resulting displays have 150‐dpi color resolution, an aperture ratio of over 35%, and excellent image quality, making them the first high‐resolution displays that are suitable for notebook applications.
A spatial extension of CIELAB for digital color‐image reproduction
Authors: Zhang X. , Wandell B. A.
Published: May 2006

Abstract— We describe a spatial extension to the CIELAB color metric that is useful for measuring color reproduction errors of digital images. To compute the error, digital color images are spatially filtered using a pattern‐color separable method and then converted into the CIELAB representation. Over patterned regions of the image, the reproduction errors measured using the spatial extension of CIELAB correspond to perceived color errors better than errors computed without the spatial extension. Over uniform spatial regions of the image, errors computed with the extension are equal to errors computed using the standard CIELAB formulae.
Measuring visual effectiveness of dim light
Authors: Howard C. M.
Published: May 2006

Abstract— Photometric instruments measure either photopic or scotopic luminance. In the range between 2 and −3 log cd/m2 both cones and rods are active. Is there a satisfactory way to calculate a measure of visual effectiveness in this mesopic region? Some methods are under evaluation by the CIE; comments from display users can help this process.
An overview of needs for a unified display interface standard
Authors: Myers B.
Published: May 2006

Abstract— The need for an improved interface standard, addressing the unique requirements of non‐CRT display technologies, is currently one of the major obstacles preventing the wider acceptance of such products as replacements for the traditional CRT‐based monitor. This paper examines the specific needs which must be addressed by such a standard, in order to provide a truly technology‐independent interface.
Electrochemical formation of ZnS screens
Authors: Colletti L. P. , Slaughter R. , Stickney J. L.
Published: May 2006

Abstract— This paper is a preliminary report on the formation of ZnS thin films thicker than five monolayers using electrochemical atomic layer epitaxy (ECALE). Thin films were electrodeposited on Au‐coated Si wafers and ITO‐coated borosilicate glass slides. The deposits' morphology was examined by scanning electron microscopy and composition was determined by electron probe microanalysis. Grazing‐angle x‐ray diffraction showed cubic (111) ZnS films.
A novel deposition method for thin‐film electroluminescent devices
Authors: Hiskes R. , DiCarolis S. A. , Mueller‐Mach R. , Mazzi V. , Nauka K. , Mueller G. O.
Published: May 2006

Abstract— Thin ZnS:Mn and SrS:Ce electroluminescent films are grown by solid‐source metal‐organic chemical vapor deposition (MOCVD). The method is attractive because it uses relatively non‐toxic materials and does not require flammable hydrogen or toxic H2S. Performance results are presented for both blue‐ and white‐emitting phosphors. Even though the method has not yet been optimized, luminous efficacy of 3 lm/W at low drive voltages has been attained for ZnS: Mn.
Self‐limiting growth of ZnS on Si substrates at a growth rate of 0.7 monolayers per operating cycle by atomic layer epitaxy using MOCVD
Authors: Liu C. H. , Yokoyama M. , Su Y. K. , Lee N. C.
Published: May 2006

Abstract— ZnS films were grown on (100) Si substrates by atomic layer epitaxy (ALE) using a metal‐organic chemical vapor deposition system. We studied the growth rate as a function of the substrate temperature and the flow rates of DMZn and H2S. The growth rate was kept constant at 0.7 monolayers per cycle and was independent of substrate temperature in the range 125–225°C, and of the mole fractions of both DMZn and H2S. Although the “fractional ALE” growth does not produce a two‐dimensional surface, SEM micrographs show smooth ZnS films with the atomic ratio of S: Zn very close to unity.
The processing and characterization of CaGa2S4:Ce blue phosphor by MOCVD
Authors: Moss T. S. , Smith D. C. , Samuels J. A. , Dye R. C. , DelaRosa M. J. , Schaus C. F.
Published: May 2006

Abstract— The deposition of CaS, Ga2S3, and CaGa2S4:Ce has been accomplished by MOCVD using Ca(tmhd)2, Ga(tmhd)3, and Ce(tmhd)4, with a liquid delivery system to control the flows. Samples were primarily characterized using x‐ray fluorescence and electroluminescence measurements of the color and luminance. Analysis shows the CaS deposition is mass‐transport limited, while the Ga2S3 is limited by the deposition kinetics. However, application of these mechanisms to the CaGa2S4:Ce deposition system reveals that the CaGa2S4:Ce is independent of its components. Further, the deposition of CaGa2S4:Ce is found to be Ca‐rich under conditions which lead to low Ga/Ca ratios in the deposited film. This indicates that the conversion of Ca from Ca(tmhd)2 was catalyzed by the slight presence of Ga in the form of CaGa2S4:Ce or Ga2S3 on the surface. The Ca is thought to be deposited as CaS: Ce, since there is a shift in the EL color towards green under low Ga/Ca ratios. The Ca conversion is found to approach values predicted by the CaS deposition mechanism under conditions which lead to high Ga/Ca ratios, implying that excess Ga2S3 is needed for the deposition of CaGa2S4:Ce without any CaS:Ce inclusions.
Low‐temperature synthesis and particle‐size control in yttrium‐based phosphors
Authors: Ravichandran D. , Roy Rustum , White William B.
Published: May 2006

Abstract— Yttrium‐based phosphors: Y2O3:Eu+3, Y2O3:Tb+3, Y2SiO5:Eu+3, Y2SiO5:Tb+3, and Y3Al5O12:Eu+3, Y3Al5O12:Tb+3 have been made by sol‐gel processes via organic precursors. In all the compositions, transparent non‐crystalline xerogels were reacted either by dry firing or by hydrothermal reaction. At temperatures of 600–650°C, the gels reacted to single‐phase well‐crystallized anhydrous compounds as shown by powder x‐ray diffraction. Luminescent emission measurements are presented for all the rare‐earth‐activated yttrium‐based compounds. Scanning electron microscopy reveals a particle size of <0.2 μm with a morphology of loose aggregates in the case of Eu‐doped samples.
Optimization and enhancement of fluorescence in strontium sulphide by cadmium incorporation
Authors: Ray B. , Lenton P. , Arterton B. W. , Viney I. V. F. , Brightwell J. W. , Clough S.
Published: May 2006

Abstract— Solid solutions of Sr1−xCdxS, up to the solid solubility limit of x = 0.03, have been prepared by two methods to produce powders with high and low Cd concentrations. Substantially enhanced photoluminescence emission was observed at both 77 and 300K with the greatest effect occurring at x around 0.001. The emission was centered around 420 nm for the most intense sample, at x = 0.0008, with a half‐width of 50–100 nm depending on temperature. At 300K, for higher Cd concentrations, there was considerable broadening of the emission with a shift in the peak to longer wavelengths and a distinctive shoulder between 550 and 600 nm. It is conjectured that the emission processes are linked to divalent Cd ions with broadening resulting at higher Cd concentrations due to differing ion environments and related local lattice strain.
Advantages of self‐propagating combustion reactions for synthesis of oxide phosphors
Authors: Shea L. E. , McKittrick J. , Lopez O. A. , Sluzky E. , Phillips M. L. F.
Published: May 2006

Abstract— Combustion synthesis was explored as an alternate synthetic route to producing oxide phosphors with improved luminescent properties. The technique involves the highly exothermic reaction of metal nitrates (oxidizers) with an organic fuel (e.g., urea, carbohydrazide, glycine) at 500°C. We have synthesized Tb3+, Eu3+, Tm3+, and Cr3+‐activated Y3Al5O12 (YAG), Y2O3:Eu3+, and Y2SiO5:Ce3+ phosphors. As‐reacted powders are well‐crystallized, luminescent, and have a small particle size. The effects of processing parameters such as type of fuel and fuel/oxidizer ratio on the spectral energy distribution were determined using photoluminescence measurements. Low‐voltage (100–1000 V) efficiency of combustion‐synthesized phosphors was compared with efficiencies obtained for phosphors prepared via hydrothermal synthesis and high‐temperature solid‐state reaction.
New inorganic phosphors confined in glass and ceramic matrices
Authors: Morita M. , Herren M.
Published: May 2006

Abstract— A study of the optical properties of new amorphous matrices containing transition‐metal and rare‐earth ions is reported. It is shown that activator electronic states are strongly influenced by the host matrix.
Properties of charge carriers in ZnS and their effect on the excitation of Mn
Authors: Corlatan D. , Neyts K. , De Visschere P. , Van den Bossche J. , Maximus B.
Published: May 2006

Abstract— The subjects of this investigation are the transport of charge carriers and the spatial efficiency in thin‐film electroluminescent devices based on ZnS: Mn. Measurements with optional UV illumination were performed on a set of probe layer samples. The transfer of electrons and holes was studied and by comparing transient measurements with the steady‐state situation the creation of positive space charge during the first pulses is revealed and its location is estimated.
Characterization of the electrical properties of SrS:Ce thin‐film electroluminescent devices
Authors: Ohmi Koutoku , Ishitani Katsuaki , Kashio Yukinori , Tanaka Shosaku , Kobayashi Hiroshi
Published: May 2006

Abstract— The electrical properties of SrS:Ce thin‐film electroluminescent (TFEL) devices were studied. Photo‐irradiation effects on capacitance‐voltage and charge‐voltage characteristics of SrS:Ce TFEL devices were measured and compared with those of ZnS: Mn devices. For the SrS:Ce device, the polarization charge due to the positive space charge was estimated to be 0.94 μC/cm2. This polarization charge was remarkably reduced by photo‐irradiation. For the ZnS: Mn TFEL device, the polarization charge due to the positive space charge was 0.66 μC/cm2. However, the reduction of the polarization charge by photo‐irradiation was small compared to that of the SrS:Ce device. The unique electrical and optical characteristics observed in the SrS:Ce TFEL devices such as relaxation of phosphor field and leading‐ and trailing‐edge emissions are considered as functions of the large amount of space charge and also due to the electron emission from electron traps and electron recapture by the traps.
The current status of thin‐film electroluminescence
Authors: Mauch Reiner H.
Published: May 2006

Abstract— The current status of inorganic and organic electroluminescence (EL) is summarized. Emphasis is given to recent developments for full‐color displays. Advantages and drawbacks of both technologies are discussed and possible fields of applications are identified. In the case of inorganic EL, the most important task is the development of an efficient blue material. Organic EL has to overcome stability problems if these technologies are to be considered for high‐information‐content full‐color flat‐panel‐display applications.
The transient response and dynamic drive of cholesteric liquid‐crystal displays
Authors: Huang X.‐Y. , Doane J. W. , Yang D.‐K.
Published: May 2006

Abstract— Transient phenomena play important roles in switching bistable reflective cholesteric liquid‐crystal displays (Ch‐LCDs). The transition to the transient planar state through the conic helical relaxation is discussed. The transition time is on the order of 1 ms and is utilized in the design of the dynamic drive scheme to substantially improve the drive speed of Ch‐LCDs. Systematic studies of the electro‐optical response under this drive scheme are presented as well as the drive‐scheme implementation.
Analysis of pixel charging in MIM‐LCDs
Authors: Lauer Hans‐Ulrich
Published: May 2006

Abstract— MIM‐LCDs are currently addressed by the three‐, four‐, and five‐level driving schemes. In order to get a good estimation of the required line and column voltages, the differential equation that describes the pixel charging via a MIM is solved. From this solution, formulae for the line and column voltages are derived. By using an approximation polynomial, a fast numerical evaluation of the analytical expressions is possible.
Effects of various hydrogen‐passivation techniques on the performance of a‐SiC:H‐based p‐i‐n‐type thin‐film visible‐light‐emitting diodes
Authors: Lee Jong‐Wook , Lim Koeng Su
Published: May 2006

Abstract— The effects of various hydrogen‐passivation processes on the performance of a‐SiC:H‐based p‐i‐n‐type thin‐film visible‐light‐emitting diodes (TFLEDs) fabricated by a photo‐CVD method have been investigated. A hydrogen‐passivation process was performed by three methods: in‐situ hydrogen passivation by a photo‐CVD method, ex‐situ hydrogen passivation via a plasma, and two‐step hydrogen passivation in which the in‐situ hydrogen‐passivation process was followed by an ex‐situ one. It was found that a hydrogen‐passivation process remarkably improved the device performance and that the two‐step hydrogen‐passivation process was most effective; i.e., decrease of the threshold voltage by about 2 V, shift of the EL peak wavelength from 700 to 590 nm, and increase of the luminance up to 128 cd/m2; and that improvement of the device performance by the hydrogen‐passivation process was dominantly caused by a decrease of midgap states by hydrogen atoms.
Improved lamp and polarizers for subtractive color displays
Authors: Post David L. , Dodd Sonia R. , Heinze William C. , Shaffner Richard O.
Published: May 2006

Abstract—A new lamp and a set of color polarizers have been developed for use with subtractive‐color active‐matrix liquid‐crystal displays (AMLCDs). The lamp is a xenon‐based ac‐operated short‐arc design with metal halides added to produce radiation at the desired wavelengths. The polarizers are made from crosslinked cholesteric liquid‐crystal silicones and have spectral polarization functions that are tuned to match the lamp's emission spectrum. The resulting subtractive‐color AMLCD has substantially greater transmittance, contrast, and color gamut than our previous designs.
Optimization for black and white representation in reflective STN‐LCDs with single polarizers
Authors: Komura S. , Itoh O. , Kondo K.
Published: May 2006

Abstract— An optimization method is proposed for achieving black and white representation in reflective STN‐LCDs with single polarizers which consist of an STN cell, a polarizer, and a reflector with two birefringent films between the STN cell and the reflector. In this method, the two films are optimized to achieve good black representation while an optimum voltage is applied to the STN cell. Good black and white representation with a maximum contrast ratio of 5:1, reflectance of 22%, and good achromaticity are achieved for an STN‐LCD fabricated using this method.
Reflective display with photoconductive layer and bistable reflective cholesteric mixture
Authors: Yoshida Hidefumi , Takizawa Yutaka , Martin Todd M. , West John L.
Published: May 2006

Abstract— A reflective display was developed using a bistable reflective cholesteric formulation. It was addressed by using a photoconductive layer. An image was written on the liquid‐crystal layer by transmitting white light through a TFT‐LCD or slide film. Because the cholesteric materials are bistable, the displayed image remains after the applied voltage is removed and even when irradiated with intense light.
Thin‐film‐transistor‐ and diode‐addressed AMLCDs on polymer substrates
Authors: Young N. D. , Bunn R. M. , Wilks R. W. , McCulloch D. J. , Deane S. C. , Edwards M. J. , Harkin G. , Pearson A. D.
Published: May 2006

Abstract— Amorphous‐silicon‐rich nitride (αSiNx:H) thin‐film diodes (TFDs) have been fabricated on glass, polyethersulphone (PES), polyacrylate (PAR), and polyethelyenenaphthalate (PEN) substrates at temperatures of 150–200°C, and a TFD‐addressed TN‐LCD fabricated on polyethersulphone is presented. Furthermore, poly‐Si thin‐film‐transistors (TFTs) have been fabricated on glass, polyimide (PI), and polyethersulphone at temperatures of 200–275°C, and active‐matrix arrays with drive circuitry have been realized. This work is an important step leading to a compact, lightweight, robust, system on a panel.
Optical properties of general twisted‐nematic liquid‐crystal displays
Authors: Yeh Pochi
Published: May 2006

Abstract— The optical properties of the field‐off state of a general twisted‐nematic liquid‐crystal display (TN‐LCD) are investigated by using the simple Jones matrix method. Analytic expressions for the transmission properties of the display are obtained. Without resorting to differential equations, the author obtained results which are identical to those obtained previously by using Riccati differential equations. These analytic expressions are extremely useful for explaining the working mechanism of the conventional TN‐LCDs and various STN, OMI, and LTN‐LCDs. In addition, they are also useful for the experimental measurement of the cell gap and twist angle of a general TN‐LCD.
Optical studies of anisotropic networks in polymer‐stabilized liquid crystals
Authors: Hudson Christine M. , Chien L.‐C. , Klouda Ralph
Published: May 2006

Abstract— Polymer‐stabilized liquid crystals form a class of unique materials in advanced flat‐panel‐display technology. We have synthesized azo‐containing diacrylate monomers and have used their dichroic nature to study the anisotropic nature of the polymer network formed upon photopolymerization in a nematic solvent in 5‐ and 10‐μm cells. The effects of monomer structure, concentration, and UV dose on the order parameter have been studied. While order parameter does not appear to be dependent upon the intensity of the UV light used in the polymerization, SEM photos and electro‐optic studies of the cells indicate a dependence of the network morphology and cell response on UV lamp intensity.
FLC wobbling for high‐resolution projectors
Authors: Yasuda Akio , Nito Keiichi , Matsui Eriko , Takanashi Hidehiko , Kataoka Nobue , Shirochi Yoshiki
Published: May 2006

Abstract— There is a tradeoff between brightness and resolution in high‐resolution displays. A new wobbling technique apparently doubles the number of pixels in AMLCDs without reducing the brightness. A wobbling device is composed of a ferroelectric‐liquid‐crystal (FLC) device and a quartz‐crystal plate. The FLC device rotates the polarized plane of light irradiated from TFT‐LCDs. The FLC wobbling device is combined with a projector which uses three TFT‐LCD panels with 480 horizontal lines to apparently double the vertical resolution to 800–1000 lines. A depixelization effect, which eliminates the pixel images on the screen resulting in a smooth CRT‐like picture, was observed. The device survived mechanical shocks at the 100‐m/s2 level and continuous driving at 75°C for more than 1000 hours, thus confirming its high reliability. We have also developed a new FLC mixture for the device with a smectic‐C* temperature range from −33 to 86°C.
Stereoscopic image representation with synthetic depth of field
Authors: Blohm W. , Beldie I. P. , Schenke K. , Fazel K. , Pastoor S.
Published: May 2006

Abstract— A novel concept of stereoscopic imaging providing a depth‐of‐field blur effect close to that experienced in natural vision is presented. With this concept, only a mini‐volume of the reproduced three‐dimensional space is displayed in full spatial resolution. This volume is centered around the current point of fixation of the viewer. In an exploratory study, the concept of a so‐called “depth‐of‐interest” (DOI) display was evaluated. Subjects assessed computer‐generated 3D images with different depth‐selective filtering characteristics (i.e., varying in‐depth extents of the mini‐volume with full resolution). Results indicate that the DOI display can indeed improve 3D viewing comfort. Apparently, a somewhat smaller depth of field than experienced in natural vision is preferred in stereoscopic image representations.
The heat dissipation in Litz wires of CRT deflection coils
Authors: Harberts D. W.
Published: May 2006

Abstract— A model is presented for the dissipation of CRT deflection coils allowing for better designs with lower dissipation. With experimental results it is shown that at high scan frequencies the skin effect in Litz wires can no longer be neglected compared to proximity losses. The reduction of the dissipation by increasing the number of separate conductors in a Litz wire is limited to the point where the losses due to the proximity effect become comparable to those due to the skin effect.
A new coma correction system
Authors: Sluyterman A. A. S.
Published: May 2006

Abstract— A new cost‐effective vertical coma‐correction system for in‐line CRTs has been designed, offering better spot quality compared with conventional methods using shunts in the gun. In contrast to other coma‐correction systems with improved spot, this system is particularly well suited for use in East‐West raster‐corrected yokes.
Organic multicolor EL display with fine pixels
Authors: Hosokawa C. , Matsuura M. , Eida M. , Fukuoka K. , Nakamura H. , Kusumoto T.
Published: May 2006

Abstract— We present a RGB multicolor EL display, in which a blue organic EL display was combined with color‐changing media (CCM). The CCMs were basically made up of organic fluorescent media which changed the emission color from blue to green or red.
FEDs based on the concept of a transparent cathode
Authors: Séméria M.‐N. , Rommeveaux Ph. , Meyer R. , Montmayeul B. , Vabre M. , Chaton Oules C. , Muller F. , Blanc R.
Published: May 2006

Abstract— FED technology has been expanded to implement the concept of a transparent cathode, and displays have been fabricated and tested. We describe both the transparent cathode and the anode. We explain how we avoid optical parasitic effects and we present the optical characteristics of both monochrome and full‐color displays. As a conclusion, we highlight the major interest of this solution in the context of low‐voltage FEDs.