Liquid Crystal Display (liquid + crystal_display)

Distribution by Scientific Domains


Selected Abstracts


Bit-length expansion for digital images

ELECTRONICS & COMMUNICATIONS IN JAPAN, Issue 10 2009
Tomoaki Kimura
Abstract Bit-length of digital images is decided by the Analog-to-Digital (AD) converter. The bit-length expansion technique is necessary for high-quality displays such as the liquid crystal display (LCD) and the plasma display. Bit-length expansion is also necessary for low-bit length images, which are degraded by the pseudo-contour. In this paper, we propose a bit-length expansion method from M -level to N -level [N=3(M,1)+1]. This operation means that two quantization levels are introduced between existing levels. The bit-length expansion method results in the estimation problem of an error image between an M -level's image and an N -level's image. The error image is the pattern image which consists of three values. We show the estimation method of the three values pattern image and that the proposed method can remove the pseudo-contour of digital images through several application results. © 2009 Wiley Periodicals, Inc. Electron Comm Jpn, 92(10): 32,40, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecj.10105 [source]


Discovery of New Green Phosphors and Minimization of Experimental Inconsistency Using a Multi-Objective Genetic Algorithm-Assisted Combinatorial Method

ADVANCED FUNCTIONAL MATERIALS, Issue 11 2009
Asish Kumar Sharma
Abstract A multi-objective genetic algorithm-assisted combinatorial materials search (MOGACMS) strategy was employed to develop a new green phosphor for use in a cold cathode fluorescent lamp (CCFL) for a back light unit (BLU) in liquid crystal display (LCD) applications. MOGACMS is a method for the systematic control of experimental inconsistency, which is one of the most troublesome and difficult problems in high-throughput combinatorial experiments. Experimental inconsistency is a very serious problem faced by all scientists in the field of combinatorial materials science. For this study, experimental inconsistency and material property were selected as dual objective functions that were simultaneously optimized. Specifically, in an attempt to search for promising phosphors with high reproducibility, luminance was maximized and experimental inconsistency was minimized using the MOGACMS strategy. A divalent manganese-doped alkali alkaline germanium oxide system was screened using MOGACMS. As a result of MOGA reiteration, we identified a phosphor, Na2MgGeO4:Mn2+, with improved luminance and reliable reproducibility. [source]


Systematic optimization for the evaluation of the microinjection molding parameters of light guide plate with TOPSIS-based Taguchi method

ADVANCES IN POLYMER TECHNOLOGY, Issue 1 2010
Te-Li Su
Abstract A back light module is a key product for providing sufficient light source for a liquid crystal display (LCD). The light guide plate (LGP), used to increase the light usage rate, is a key component in the back light module. This study researches the microinjection molding process parameters and the quality performance of the LGP. Its purpose was to develop a combining Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) with the Taguchi method. This is to optimize the multiquality performance of the LGP for the injection molding manufacturing process, in which both the LCD and the LGP spontaneously produce the best quality performance for V-cut depth and angle. First, an L18 orthogonal array was planned for the manufacturing parameters that affect the microinjection molding process. These included cooling time, mold temperature, melt temperature, injection speed, injection pressure, packing pressure, packing switching, and packing time. The TOPSIS was used to deal with the single-quality optimization disadvantage of the Taguchi method. Then, the TOPSIS response table was used to obtain the optimized manufacturing parameters combination for a multiresponse process optimization. From the analysis of variance, the significant factors for the quality performance of the LGP could be obtained. In other words, by controlling these factors, it was possible to efficiently control the quality performance of the LGP. Finally, with the five verified experiments, the optimized processing parameters came within a 95% confidence interval. © 2010 Wiley Periodicals, Inc. Adv Polym Techn 29:54,63, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/adv.20181 [source]


Forecasting for the LCD monitor market

JOURNAL OF FORECASTING, Issue 4 2008
Shin-Lian Lo
Abstract The TFT-LCD (thin-film transistor,liquid crystal display) industry is one of the key global industries with products that have high clock speed. In this research, the LCD monitor market is considered for an empirical study on hierarchical forecasting (HF). The proposed HF methodology consists of five steps. First, the three hierarchical levels of the LCD monitor market are identified. Second, several exogenously driven factors that significantly affect the demand for LCD monitors are identified at each level of product hierarchy. Third, the three forecasting techniques,regression analysis, transfer function, and simultaneous equations model,are combined to forecast future demand at each hierarchical level. Fourth, various forecasting approaches and disaggregating proportion methods are adopted to obtain consistent demand forecasts at each hierarchical level. Finally, the forecast errors with different forecasting approaches are assessed in order to determine the best forecasting level and the best forecasting approach. The findings show that the best forecast results can be obtained by using the middle-out forecasting approach. These results could guide LCD manufacturers and brand owners on ways to forecast future market demands. Copyright 2008 John Wiley & Sons, Ltd. [source]


Developmental toxicity of indium: Embryotoxicity and teratogenicity in experimental animals

CONGENITAL ANOMALIES, Issue 4 2008
Mikio Nakajima
ABSTRACT Indium, a precious metal classified in group 13 (IIIB) in the periodic table, has been used increasingly in the semiconductor industry. Because indium is a rare metal, technology for indium recycling from transparent conducting films for liquid crystal displays is desired, and its safety evaluation is becoming increasingly necessary. The developmental toxicity of indium in experimental animals was summarized. The intravenous or oral administration of indium to pregnant animals causes growth inhibition and the death of embryos in hamsters, rats, and mice. The intravenous administration of indium to pregnant animals causes embryonic or fetal malformation, mainly involving digit and tail deformities, in hamsters and rats. The oral administration of indium also induces fetal malformation in rats and rabbits, but requires higher doses. No teratogenicity has been observed in mice. Caudal hypoplasia, probably due to excessive cell loss by increased apoptosis in the tailbud, in the early postimplantation stage was considered to account for indium-induced tail malformation as a possible pathogenetic mechanism. Findings from in vitro experiments indicated that the embryotoxicity of indium could have direct effects on the conceptuses. Toxicokinetic studies showed that the embryonic exposure concentration was more critical than the exposure time regarding the embryotoxicity of indium. It is considered from these findings that the risk of the developmental toxicity of indium in humans is low, unless an accidentally high level of exposure or unknown toxic interaction occurs because of possible human exposure routes and levels (i.e. oral, very low-level exposure). [source]


Promising Functional Materials Based on Ladder Polysiloxanes,

ADVANCED MATERIALS, Issue 15 2008
Qilong Zhou
Abstract Preparation of real ladder polysiloxanes (LPSs), including both oxygen-bridged ladder polysilsesquioxanes (LPSQs) and organo-bridged ladder polysiloxanes (OLPSs), had been a great challenge to polymer chemists from 1960 until the successful synthesis of LPSs via the supramolecular architecture-directed stepwise coupling polymerization (SCP) in the early 1980s. This opened up a new field of LPS-based advanced materials. As key building blocks, LPSs are used to construct a variety of polysiloxanes with special steric configurations and functions, such as mesomorphic LPSs, tubular polysiloxanes (TPs), and pseudo-sieve-plate polysiloxanes (pseudo-SPSs). With excellent temperature and radiation resistance, good solubility, and fine optical and mechanical properties, all these polysiloxanes demonstrate very promising prospects in the advanced materials realm. Here, the synthesis of well-ordered LPSs is presented and features of fishbone-like and rowboat-like liquid crystalline polysiloxanes are discussed. Special emphasis is given to typical applications of LPSs, TPSs, and pseudo-SPSs in the areas of liquid crystal displays, microelectronics packaging, and nonlinear optical materials. [source]


The co,evolution of technologies and institutions: a comparison of Taiwanese hard disk drive and liquid crystal display industries

R & D MANAGEMENT, Issue 3 2002
Chang Hung
In this paper, we examine the different evolutionary processes and outcomes of the hard disk drive and liquid crystal display industries in Taiwan. To this end, we make two general theoretical claims. First, that an appreciation of the globalization of technology is as important as national institutions in understanding industry development in catch,up economies such as Taiwan. Second, in addressing both industrial survival and failure, that national institutions can have either a positive or a negative impact on sectoral activities. Empirically, we show that, in Taiwan, rigid social institutions conflict with the hard disk drive technology. This conflict, in turn, produces obstacles to Taiwanese firms' search for new markets and skills in hard disk drives. On the other hand, Taiwan's institutional structures provide a source of technical efficiency and market opportunity for the emerging liquid crystal display trajectory. This, in turn, drives Taiwanese industry towards adopting new practices in the manufacture of liquid crystal displays. [source]