[in Japanese]

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An advanced capacitively coupled driving method, which can produce a cross talk suppressed image and has a low voltage operation, is described This new driving method utilizes the capacitively coupled voltage which is supplied to the pixel electrode through the storage capacitor formed between the preceding or next gate line and the pixel From a TFT array circuit simulation of the dynamic behavior of a pixel voltage and also from the experimental results of the optical characteristics of TFT-LCDs, driven by this new driving method, it was found that this new driving method is effective in suppressing the cross talk for large scale and high resolution TFT-LCDs This driving method was used to demonstrate a highly uniform and a cross talk free image with low data voltage driving in the 152 in diagonal IPS mode TFT-LCD with a wide aspect ratio

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We propose a new TFT-LCD structure without a black matrix based on the Super HA (High Aperture) structure which uses organic resin as an insulating layer between the pixel electrodes and signal lines In this structure, the conventional black matrix is replaced by stacks of two color filter layers in the display area In the peripheral area, one of the two metallic layers is formed to prevent light from passing through there. Using this technique, we have succeeded in developing TFT-LCDs without a black matrix on color filter substrates, while maintaining display quality This technique improves the productivity of TFT-LCDs

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In this paper we describe homeotropic splayed nematic liquid crystal displays (HSN-LCD). A pixel of a HSN-LCD is composed of three components; a pair of homeotropically aligned substrates between which nematic liquid crystal with negative dielectric anisotropy is filled, two kinds of optical compensators, and a pair of polarizers between which substrates and compensators are placed. This liquid crystal has three fundamental modes ; splay, bend, and π-twist. When the driving voltage is higher than the critical value, the Gibbs free energy of the splay-mode is the lowest among the three. The splay-mode, therefore, becomes stable. We calculated the spatial distributions of the director by using continuum theory, arid the V-T characteristics by using a 4×4 method. One compensator was optimized so as to minimize the wavelength dependence of the V-T characteristics. The other was optimized so as to maximize the viewing angle. The experimental results almost agreed with computer simulations. It was found that HSN-LCDs are promising because of their wide viewing angle and comparatively fast response characteristics.

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In many color display tubes, the focus characteristics of the red beam at the right end of the screen and of the blue beam at the left end are not very good. These poor focus characteristics are one of the causes of the degradation in the quality of display monitors. To correct this defocusing (Delta Deflection Defocusing), a new electron gun has been developed. An additional dynamic focus voltage and the new structure of the beam apertures make it possible to give an opposite astigmatism lens effect to the red and blue beams. Therefore, it is possible to give the optimum astigmatism lens effect to all three beams over the entire screen. The newly developed electron gun contained in a 41 cm color display tube, reduced the horizontal spot size of the red beams at the right corners of the screen and of the blue beams at the left corners by up to 10%.

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This study focuses on the scanning of field-sequential stereoscopic pictures-we examined picture quality and conducted an evaluation test using a system with 525 scanning lines and a 120 Hz field frequency. The results show that in the quality of pictures displayed, the 4 : 2 or 4 : 1 interlace method, which maintains high vertical resolution, is superior to the simple 2 : 1 interlace one. We also made an experimental field-sequential stereoscopic system for a HDTV with a 4 : 2 interlace. With this 1125-scanning prototype system, we tested picture quality and confirmed that it is possible to display high-quality stereoscopic HDTV pictures of full 1125-line vertical resolutions.

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Ghosting of TV broadcasting waves caused by skyscrapers in urban areas has become a serious problem. In this paper, we describe method of quickly and effectively measuring the way in which a wall scatters TV waves. The principle of this method is based on the planar near field measurement in antenna technology. A two-element endfire array measures a wall's scattering field at each affected location from the mixed field composed of the main incidence and the scattering field. This paper describes the measuring principle, equipment, and results of experiments using a conducting plate and the wall of a building on our campus. These experiments confirm the effectiveness of this method.

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We have made improvements on the modulation transfer function (MTF) for 256 X 256-element HgCdTe back-illuminated infrared focal plane arrays (IRFPA) in the 8 to 10 pm band. In our approach, each HgCdTe photodiode is surrounded by a ditch structure to control the effective photosensitivity profile. In MTF measurements with a four-bar pattern, an IRFPA with a 9 pm deep ditch structure exhibited an improved MTF of 0.39 at the Nyquist frequency, which is about twice that of conventional planar diode structures. Using a two-dimensional model of minority-carrier diffusion in a HgCdTe epilayer, we analytically verified that the MTF increases and that the photocurrent decreases slightly as the ditch depth increases. These results suggest that using the ditch structure to control MTF is effective for resolving the detail of infrared images for back-illuminated IRFPAs.

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This paper proposes an image retrieval system which searches a database for images similar to a target imagined by a user. The system uses image features, rather than keywords, and retrieves images by reducing the multidimensional feature space generated by the feature vectors. First, the system presents the user with some sample images having suitable feature vectors and requires the user's interaction to indicate which image is similar to the one he/she has in mind. Then, the information from this interaction is used to appropriately reduce the feature space. This process is continued until the system detects the region where the initial target image is located. Since this method requires no target image and no keywords are given for any of the images in the database, it is very practical. Experimental results show the advantage and efficiency of the proposed system.

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In the process of extracting nonuniform target regions such as faces, it is necessary to identify their features. This paper proposes an active-region extraction method based on pattern recognition using a layered neural network. The neural network is used to extract features of previously given sample patterns. During the extraction, the neural network outputs the suitability of the extraction based on the features. Experimental results show that it is possible to extract some occluded parts associated with visible parts of target regions. It is also possible to extract face regions using this method.

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We propose a synchronized audio and visual (AV) decoding scheme that is tolerant of variation in the processing environment, assuming that the future AV terminal will be implemented by software. The processing environment means the set of conditions, such as workload and equipment, that defines AV processing ability. Due to its software implementation, the AV terminal might encounter fatal degradation in decoding quality when the processing environment deteriorates. To prevent this, our scheme introduces a prioritized frame packet structure (access unit) to the AV bitstream, in which the access units are selectively discarded by comparing their processing priorities with the discarding threshold. The processing priority for each access unit is determined by the relative importance of each AV stream and the relative importance of each frame within the stream. The discarding threshold is adjusted according to a decoding time stamp attached to the access unit. The proposed scheme allows us to provide the workload adjusting mechanism independently of underlying terminal implementation ; the decoding quality is gracefully degraded in the case of high workload. Experimental results show the effectiveness of our scheme against variations in the processing environment.

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In this paper we proposed a method for two dimension polygonal shape blending. The original Cartesian coordinates representation of polygon are converted to a new representation based on centroid, which can efficiently express the relations between vertices when blending two key polygons. In order to improve the results of blending, polygons are correspondingly decomposited into several sub-polygons. Main frame is formed by connecting orderly the centroids of each sub-polygon. Therefore, interpolations of main frame polygons and sub-polygons can reflect the overall interpolation in detail. Tests suggest that it work well enough and more smooth for most of realistic cases.

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