• Title/Summary/Keyword: Liquid Crystal Display (LCD)

Search Result 228, Processing Time 0.326 seconds

Viewing Angle Controllable LCD by Thermal Modulation of Optical Layer

  • Han, In-Young;Gwag, Jin-Seog;Lee, You-Jin;Kim, Jae-Hoon
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • /
    • pp.348-351
    • /
    • 2008
  • We suggest a viewing angle control mode of liquid crystal display(LCD) with additive thermal controllable optical layer [TCOL], which composed of homeotropically or homogenously well aligned LC layer and patterned hating lines on a substrate. In this system, LCD modes with wide viewing angle characteristics can be used as a main panel.

  • PDF

Data identified Time Extension Driving Method

  • Lin, L.;Liang, B.J.;Huang, C.M.;Chiang, S.P.
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • /
    • pp.1247-1250
    • /
    • 2006
  • A new liquid crystal display (LCD) Data identified Time Extension (DiTEX) driving scheme with a high charged voltage is proposed. The different charged voltage owing to the differential charging time and various initial pixel-potential can be eliminated or diminished under this method. It is compatible with a 2-row inversion and can be realized into the commercial dual-sided gate circuits.

  • PDF

Evaluation of LCD device parameters and rubbed surface of Polyimide by means of renormalized spectroscopic ellipsometry

  • Kimura, Munehiro;Hasegawa, G.;Sakamoto, H.;Akahane, T.
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • /
    • pp.1715-1718
    • /
    • 2006
  • Evaluating method of the device parameters of liquid crystal display (LCD) by means of the renormalized transmission spectroscopic ellipsometry is demonstrated. Dielectric and elastic constant, threshold voltage, pretilt angle, cell gap and Anchoring strength coefficients can be evaluated from the measurement of ellipsometric parameters measured by the symmetrically oblique incidence transmission ellipsometry (SOITE). Furthermore, rapid evaluating method for rubbed polyimide film is also demonstrated.

  • PDF

Wide-Viewing Characteristics of Self-Formed Micro-Domains in a Liquid Crystal Display with Dielectric Surface Gratings

  • Yoon, Tae-Young;Park, Jae-Hong;Yu, Chang-Jae;Lee, Sin-Doo
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • /
    • pp.452-455
    • /
    • 2002
  • We demonstrate the wide-viewing characteristics of a twisted nematic liquid crystal display (LCD) with self-formed micro-domains through the topographical alignment and fringe field effects of dielectric surface gratings (DSG). The mutual optical compensation between micro-domains within each pixel eliminates the contrast inversion phenomenon of TN mode without complex surface treatments.

  • PDF

Purification of Waste Organic Solvent Containing Propylene Glycol Monomethyl Ether Acetate (PGMEA) (PGMEA를 포함하는 폐유기용제의 정제)

  • Yoon, Kyoung-Jin;Lee, Woong-Mok;Kwon, Oh-Hoon;Kim, Jae-Yong
    • Applied Chemistry for Engineering
    • /
    • v.21 no.6
    • /
    • pp.616-620
    • /
    • 2010
  • This study was performed to recycle Propylene Glycol Monomethyl Ether Acetate (PGMEA) from Liquid Crystal Display (LCD) industry emission as a waste organic solvent by using a multistage distillation column and tried to decide optimum reflux ratio. From the final experiment result, it was confirmed ; in case the sample A, the PGMEA purity is more than 98% and the moisture is less than 0.05%, on the other hand, in case the sample B, the PGMEA purity is more than 95% when the reflux ratio is 6 and the moisture is less than 0.01% (Refer to Table 1 for the contents of sample A and B). These values means fine level which can be adapted in the LCD manufacture, requiring more than 90% common purity of recycling level.

AGV-induced floor micro-vibration assessment in LCD factories by using a regressional modified Kanai-Tajimi moving force model

  • Lee, C.L.;Su, R.K.L.;Wang, Y.P.
    • Structural Engineering and Mechanics
    • /
    • v.45 no.4
    • /
    • pp.543-568
    • /
    • 2013
  • This study explores the floor micro-vibrations induced by the automated guided vehicles (AGVs) in liquid-crystal-display (LCD) factories. The relationships between moving loads and both the vehicle weights and speeds were constructed by a modified Kanai-Tajimi (MKT) power spectral density (PSD) function whose best-fitting parameters were obtained through a regression analysis by using experimental acceleration responses of a small-scale three-span continuous beam model obtained in the laboratory. The AGV induced floor micro-vibrations under various AGV weights and speeds were then assessed by the proposed regressional MKT model. Simulation results indicate that the maximum floor micro-vibrations of the target LCD factory fall within the VC-B and VC-C levels when AGV moves at a lower speed of 1.0 m/s, while they may exceed the acceptable VC-B level when AGV moves at a higher speed of 1.5 m/s. The simulated floor micro-vibration levels are comparable to those of typical LCD factories induced by AGVs moving normally at a speed between 1.0 m/s and 2.0 m/s. Therefore, the numerical algorithm that integrates a simplified sub-structural multi-span continuous beam model and a proposed regressional MKT moving force model can provide a satisfactory prediction of AGV-induced floor micro-vibrations in LCD factories, if proper parameters of the MKT moving force model are adopted.

An integrated design approach for Light Guide Panel(LGP) of Back Light Unit(BLU) to improve the Optical Performance of Liquid Crystal Display(LCD) (LCD 제품의 광학 성능 향상을 위한 백라이트 유닛용 도광판의 최적설계)

  • Lee, Gab-Seong;Jeong, Jae-Ho;Yoon, Sang-Joon;Choi, Dong-Hoon
    • Proceedings of the KSME Conference
    • /
    • /
    • pp.1048-1052
    • /
    • 2008
  • Difficulties in developing process of Liquid Crystal Display(LCD) products such as frequent design modifications, various design requirements, and short-term development period bring on the need of integrated design approach that is efficient and easy to handle. Back Light Unit(BLU) of the LCD, which drastically affects the optical performance of LCD products, is divided into in-coupling part and out-coupling part. Serration of the in-coupling part flattens the light received from point light sources and dot pattern of the out-coupling part regularizes the light sent to screen. Therefore, the optical performance of a LCD product is largely influenced by the shape of serration and the arrangement of dot pattern. In this research, a new design approach which enables to improve the optical performance of LCD products and overcome the prementioned difficulties in developing process of LCD products is proposed. The shape of serration is parameterized to 3 parameters and out-coupling part is partitioned into 10 partitions to apply the optimization technique to this problem. 3 parameters for the shape of serration and densities of 10 partitions are used as design variables in the design optimization. Optical simulation tool named SPEOS is used to evaluate the optical performance of the LCD product. Since the optical simulation uses the random ray tracing technique, numerical noise may possibly be included in the simulation process. To solve the problem caused by numerical noise, the PQRSM which can stably find the solution of the noise problem is used in this research.

  • PDF

Assessment of hazardous substances and workenvironment for cleanrooms of microelectronic industry (전자산업 청정실의 작업환경 및 유해물질농도 평가)

  • Chung, Eun-Kyo;Park, Hyun-Hee;Shin, Jung-Ah;Jang, Jae-Kil
    • Journal of Korean Society of Occupational and Environmental Hygiene
    • /
    • v.19 no.3
    • /
    • pp.280-287
    • /
    • 2009
  • High-tech microelectronics industry is known as one of the most chemical-intensive industries. In Korea, Microelectronics industry occupied 38% of export and 16% of working employees work in microelectronics industry. But, chemical information and health hazards of high-tech microelectronics manufacturing are poorly understood because of rapid development and its penchant for secrecy. We need to investigate on chemical use and exposure control. We Site-visits to 6 high-tech microelectronics manufacturing company which have cleanroom work using over 1,000kg organic solvents (5 semi-conductor chips and its related parts company, 1 liquid crystal display (LCD)). We reviewed their data on chemical use and ventilation system, and measured TVOCs (Total Volatile Organic Compounds) and carbon dioxide concentration. All cleanroom air passed through hepa filters to acheive low particle levels and only 1 cleanroom uses carbon filters to minimize the organic solvents exposures In TVOC screening test, Cleanroom for semi-conductor chips and its related parts company with laminar down flow system (e.g. class 1~100) showed nondetectable level of TVOCs concentration, but Cleanroom for liquid crystal display (LCD) with conventional flow system (e.g. class 1,000~10,000) showed 327 ppm as TVOCs. Acetone concentration in cleanroom for Jig cleaning, LC Injection, Sealing processes were 18.488ppm (n=14), 49.762 ppm (n=15), 8.656 ppm (n=14) as arithmetric mean. Acetone concentration in cleanroom for LCD inspection process was 40ppm (n=55) as geometric mean, where the range was 7.8~128.7ppm and weakly correlated with ventilation rate efficiency(r=0.44, p<0.05). To control organic solvents in cleanrooms, chemical and carbon filters should be installed with hepa filters. Even though their volatile organic compounds concentration was not exceed to occupational exposure limits, considering of entrance limited cleanroom environment, long-term period exposure effects and adverse health effects of cleanroom worker need further reseach.

A New Design of Memory-in-Pixel with Modified S-R Flip-Flop for Low Power LCD Panel (저전력 LCD 패널을 위한 수정된 S-R 플립플롭을 가진 새로운 메모리-인-픽셀 설계)

  • Ryu, Jee-Youl;Noh, Seok-Ho
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
    • /
    • /
    • pp.600-603
    • /
    • 2008
  • In this paper, a new circuit design named memory-in-pixel for low power consumption of the liquid crystal display (LCD) is presented. Since each pixel has a memory, it is able to express 8 color grades using the data saved in the memory without the operation of the gate and source driver ICs so that it can reduce the power consumption of the LCD panel. A memory circuit consists of modified S-R flip-flop (NAND-type) implemented in the pixel, which can supply AC bias for operating the liquid crystal (LC) with the interlocking clocks (CLK_A and CLK_B). This circuit is more complex than the inverter-type memory circuit, but it has lower power consumption of approximately 50% than the circuit. We have investigated the power consumption both NAND and inverter-type memory circuit using a Smart SPICE for the resolution of $96{\times}128$. The estimated power consumption of the inverter-type memory was about 0.037mW. On the other hand, the NAND-type memory showed power consumption of about 0.007mW.

  • PDF

Image Sticking Property in the In-Plane Switching Liquid Crystal Display by Residual DC Voltage Measurements

  • Jeon, Yong-Je;Seo, Dae-Shik;Kim, Jae-Hyung;Kim, Hyang-Yul
    • KIEE International Transactions on Electrophysics and Applications
    • /
    • v.11C no.4
    • /
    • pp.142-145
    • /
    • 2001
  • The residual DC phenomena in the in-plane switching(IPS)-liquid crystal display(LCD) by the voltage-transmittance (V-T) and capacitance-voltage (C-V) hysteresis method on rubbed polyimide (PI) surfaces were studied. We found that the residual DC voltage in the IPS-LCD was decreasing with the increasing concentration of cyano LCs. The residual DC voltage of the IPS-LCD can be improved by the high polarity of cyano LCs.

  • PDF