The design of codes for distributed storage systems that protects from node failures has been studied for years, and locally repairable code (LRC) is such a method that gives a solution for fast recovery of node failures. Linear complementary dual code (LCD code) is useful for preventing malicious attacks, which helps to secure the system. In this paper, we combine LRC and LCD code by integration of enhancing security and repair efficiency, and propose some techniques for constructing LCD codes with their localities determined. On the basis of these methods and inheriting previous achievements of optimal LCD codes, we give optimal or near-optimal [n, k, d;r] LCD codes for k≤6 and n≥k+1 with relatively small locality, mostly r≤3. Since all of our obtained codes are distance-optimal, in addition, we show that the majority of them are r-optimal and the other 63 codes are all near r-optimal, according to CM bound.
In this paper, we describe the Galois dual of rank metric codes in the ambient space FQn×m and FQmn, where Q=qe. We obtain connections between the duality of rank metric codes with respect to distinct Galois inner products. Furthermore, for 0 ≤ s < e, we introduce the concept of qsm-dual bases of FQm over FQ and obtain some conditions about the existence of qsm-self-dual basis.
Xubo ZHAO Xiaoping LI Runzhi YANG Qingqing ZHANG Jinpeng LIU
In this paper, we study Hermitian linear complementary dual (abbreviated Hermitian LCD) rank metric codes. A class of Hermitian LCD generalized Gabidulin codes are constructed by qm-self-dual bases of Fq2m over Fq2. Moreover, the exact number of qm-self-dual bases of Fq2m over Fq2 is derived. As a consequence, an upper bound and a lower bound of the number of the constructed Hermitian LCD generalized Gabidulin codes are determined.
Itaru KAMOHARA Ulrich WELLING Ulrich KLOSTERMANN Wolfgang DEMMERLE
This paper presents a simulation study on the printing behavior of three different EUV resist systems. Stochastic models for negative metal-based resist and conventional chemically amplified resist (CAR) were calibrated and then validated. As for negative-tone development (NTD) CAR, we commenced from a positive-tone development (PTD) CAR calibrated (material) and NTD development models, since state-of-the-art measurements are not available. A conceptual study between PTD CAR and NTD CAR shows that the stochastic inhibitor fluctuation differs for PTD CAR: the inhibitor level exhibits small fluctuation (Mack development). For NTD CAR, the inhibitor fluctuation depends on the NTD type, which is defined by categorizing the difference between the NTD and PTD development thresholds. Respective NTD types have different inhibitor concentration level. Moreover, contact hole printing between negative metal-based and NTD CAR was compared to clarify the stochastic process window (PW) for tone reversed mask. For latter comparison, the aerial image (AI) and secondary electron effect are comparable. Finally, the local CD uniformity (LCDU) for the same 20 nm size, 40 nm pitch contact hole was compared among the three different resists. Dose-dependent behavior of LCDU and stochastic PW for NTD were different for the PTD CAR and metal-based resist. For NTD CAR, small inhibitor level and large inhibitor fluctuation around the development threshold were observed, causing LCDU increase, which is specific to the inverse Mack development resist.
Takumi SHOJI Yosei SHIBATA Takahiro ISHINABE Hideo FUJIKAKE
In recent years, flexible liquid crystal displays (LCDs) have attracted much attention due to their thin and lightweight designs, as well as their ease of installation compared with conventional flat-panel LCDs. Most LCDs require backlight units (BLUs) to yield high-quality images. However, the luminance uniformity of flexible BLUs is drastically reduced in the curved state, as the light emitted from a typical BLU is mainly directed in the normal direction. Conventional BLUs do not provide the image quality of flexible BLUs due to uneven luminance distribution from the perspective of the observer. To overcome these issues, here we introduce a novel oblique-angled notched film for improved light distribution of a conventional BLU. The notched structure of the proposed film exhibits V-shaped split behavior during curvature. This elastic deformation is expected to compensate for the spatial luminance of the light emitted from the BLU. We investigated the design requirements for the proposed film based on geometrical calculations. The luminance distribution of a flexible BLU was then simulated using the proposed film, based on geometrical optics theory. The simulation results confirmed that the direction of travel of the light is controllable according to the total internal reflection of the proposed film, thus improving the luminance uniformity of the BLU in a convex-curved state. Based on these results, the proposed approach is expected to improve the luminance uniformity of convex-curved flexible LCDs.
We investigate linear complementary dual (LCD) rank-metric codes in this paper. We construct a class of LCD generalized Gabidulin codes by a self-dual basis of an extension field over the base field. Moreover, a class of LCD MRD codes, which are obtained by Cartesian products of a generalized Gabidulin code, is constructed.
Let $mathbb{F}_q$ be a finite field of q elements, $R=mathbb{F}_q+umathbb{F}_q$ (u2=0) and D2n=
The overdrive technique is widely used to eliminate motion blur in liquid-crystal displays (LCDs). However, this technique requires a large frame memory to store the previous frame. A reduction in the frame memory requires an image compression algorithm suitable for real-time data processing. In this paper, we present an algorithm based on multimode-color-conversion block truncation coding (MCC-BTC) to obtain a constant output bit rate and high overdrive performance. The MCC-BTC algorithm uses four compression methods, one of which is selected. The four compression modes either use the single-bitmap-generation method or the subsampling method for chrominance. As shown in the simulation results, the proposed algorithm improves the performance of both coding (up to 2.73dB) and overdrive (up to 2.61dB), and the visual quality is improved in comparison to other competing algorithms in literature.
A Uniform Lying Helix (ULH) liquid crystal device (LCD) fabricated by utilizing the characteristics of shear flow alignment as well as dielectric anisotropy was demonstrated. Cholesteric liquid crystals with a short helical pitch can exhibit an electric field-induced tilt. These experimental results indicate that it is possible to realize a high-speed response flexible LCD using plastic substrates.
Hiroyuki MANABE Munekazu DATE Hideaki TAKADA Hiroshi INAMURA
Liquid crystal displays (LCDs) are suitable as elements underlying wearable and ubiquitous computing thanks to their low power consumption. A technique that uses less power to drive 1-pixel LCDs is proposed. It harvests the charges on the LCD and stores them in an external capacitor for reuse when the polarity changes. A simulation shows that the charge reduction depends on the ratio of the capacitance of the external capacitor to that of the LCD and can reach 50%. An experiment on a prototype demonstrates an almost 30% reduction with large 1-pixel LCDs. With a small 10 × 10mm2 LCD, the overhead of the micro-controller matches the reduction so no improvement could be measured. Though the technique requires longer time for polarity reversal, we confirm that it does not significantly degrade visual quality.
Sang Hyuck BAE Jaewon PARK CheolSe KIM SeokWoo LEE Woosup SHIN Yong-Surk LEE
In this letter, we evaluate the parasitic capacitance of an LCD touch panel, the description and implementation of a differential input sensing circuit, and an algorithm suitable for large LCDs with integrated touch function. When projected capacitive touch sensors are integrated with a liquid crystal display, the sensors have a very large amount of parasitic capacitance with the display elements. A differential input sensing circuit can detect small changes in the mutual capacitance from the touch of a finger. The circuit is realized using discrete components, and for the evaluation of a large-sized LCD touch panel, a printed circuit board touch panel is used.
Akira SAKAIGAWA Masaaki KABE Tsutomu HARADA Fumitaka GOTO Naoyuki TAKASAKI Masashi MITSUI Tae NAKAHARA Kojiro IKEDA Kenta SEKI Toshiyuki NAGATSUMA Amane HIGASHI
Battery life and outdoor visibility are two of the most important features for mobile applications today. It is desirable to achieve both low power consumption and excellent outdoor visibility on the display device at the same time. We have previously reported a new RGBW method to realize low power consumption and high luminance with high image quality. In this paper, the basic concept of a new RGBW calculation utilizing an “Extended HSV color space” model is described, and also its performance, such as low power consumption, color image reproducibility and outdoor visibility is presented. The new method focuses on the luminance-increase ratio by means of a White signal for the display image data, and derives the appropriate RGBW signal and backlight PWM signal for every frame period. This dynamically controlled system solves the problems of conventional RGBW systems, and realizes the same image quality as a corresponding RGB display. In order to quantify its color image reproducibility, a spectroscopic measurement has been completed using the Macbeth Color Chart. In addition, the advantages of high luminance by the new RGBW method is described. The converted tone curve with an RGBW method provides very high luminance, such as 1,000cd/m2, and improved outdoor visibility. Finally, a newly developed 4.38-inch full-HD (1,080 × 1,920) 503ppi prototype LCD utilizing this new RGBW technology is described.
We designed multilayer wavelength-selective reflector films by stacking thin-films of transparent polymer. The optimum structure of the multilayer is determined using a combination of characteristic matrix method and a version of genetic algorithm. Such multilayer films can be used in LCD devices to enhance the color saturation of the display.
Kuo-Jen LIN Chih-Jen CHENG Hsin-Cheng SU Jwu-E CHEN
A CMOS current-mode S-shape correction circuit with shape-adjustable control is proposed for suiting different LCD panel's characteristics from different manufactures. The correction shape is divided into three segments for easy curve-fitting using three lower order polynomials. Each segment could be realized by a corresponding current-mode circuit. The proposed circuit consists of several control points which are designed for tuning the correction shape. The S-shape correction circuit was fabricated using the 0.35 µm TSMC CMOS technology. The measured input dynamic range of the circuit is from 0 µA to 220 µA. The -3 dB bandwidth of the circuit is up to 262 MHz in a high input current region.
Ichiro HIROSAWA Tomoyuki KOGANEZAWA Hidenorii ISHII
Grazing incidence X-ray diffraction experiment proved that the a- and c-axes of PMDA-ODA crystals preferentially aligned in normal and parallel directions to rubbing at surface of rubbed film, and that polymer chains of residual amorphous phase aligned in rubbing direction.
Seok-Min CHAE In-Ho SONG Sung-Hak LEE Kyu-Ik SOHNG
In this study, we show that the motion blur is caused by exposure time of video camera as well as the characteristics of LCD system. Also, we suggest that evaluation method of motion picture quality according to the frequency response of video camera and LCD systems of hold and scanning backlight type.
The Liquid-crystal display (LCD) overdrive technique has been utilized to reduce motion blur on a display via a reduction in the response time. However, to measure the variation of the pixel amplitudes, it is necessary to store the previous frame using a large frame memory. To downscale the frame memory, block truncation coding (BTC) is commonly employed due to the simplicity of its implementation, even if some visual artifacts may occur for image blocks with high frequency components. In this paper, we present a multimode-multilevel BTC (MBTC) technique that improves performance while maintaining simplicity. To improve the visual quality, we uniquely determine the quantization level and coding mode of each block according to the distribution of the luminance and chrominance amplitudes. For a compression ratio of 6:1, the proposed method demonstrates higher coding efficiency and overdrive performance by up to 3.81 dB in the PSNR compared to other methods.
Ichiro HIROSAWA Tomoyuki KOGANEZAWA Hidenori ISHII
Depth profile of mass density of vertical alignment film was investigated by X-ray reflectivity, in order to characterize side chains at film surface for vertical alignment of liquid crystals. Existence thin and low density top layer at surface of polyimide film, which was considered to be side chains, was clearly detected. Furthermore, existence of high density layer just below side chain layer was also found, and it is suggested that backbone chain ordering at film surface. Effect of rubbing on VA film was not detected. However, density growth by annealing just below side chain layer of rubbed VA film suggests more ordered backbone chain alignment induced by rubbing.
Aldhino ANGGOROSESAR Young-Jin KIM Kee-Wook RIM
Backlight dimming techniques have been researched much to obtain high power saving on display modules, especially those which are based on LCD. The use of LED as a light source in a backlight module has opened a wider chance to perform local dimming as an improvement of a conservative global dimming approach. However, local dimming techniques are sometimes observed to obtain worse performance than global dimming ones in terms of power saving or image fidelity. We observed that even some of their results show visible artifacts. In this paper, we propose a novel backlight dimming technique called hybrid dimming, which combines local and global dimming approaches effectively. We do local dimming to obtain the initial backlight levels while calculating its SSIM index, which is a human visual system-aware image quality metric. We then make sure that these backlight levels don't exceed the ones obtained from a human visual system-aware global dimming with similar image fidelity. As a result, our proposed method can gain better power saving than a human visual system-aware global dimming and prior local dimming techniques, while making little difference in the image fidelity and suppressing visible block artifacts in the results. Experimental results showed that the proposed technique can achieve up to 14, 2.2, and 2.4 times higher power saving ratio than human visual system-aware global dimming and two well-designed local dimming techniques, respectively.
Remi KAWAKAMI Satoshi NIIYAMA Yutaka NAKAGAWA Yuji SODA
We proposed a novel UV curable reactive mesogen monomer for VA-LCD with Polymer-Sustained (Stabilized) Vertical Alignment (PSVA) which shows a high display performance. The experimental results reveal that the PSVA by the novel-monomer realizes less image sticking and better response time.