In this paper, we investigate a 3D display using a Liquid Crystal Gradient Refractive Index (LC GRIN) lens. We optimized the structure of the LC GRIN lens and the parameters of the liquid crystal to obtain ideal refractive index dispersion. The dispersion of the refractive index was examined in detail in both an experiment and a simulation. The crosstalk measurement of the 3D display using a LC GRIN lens corresponded well to simulated results based on the measured dispersion of refractive index. A crosstalk value of 2.5% for two views is achieved in our 3D display using the LC GRIN lens.

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A head-up display (HUD) superimposes the reflected display image and background space and is expected to be a new display that achieves augmented reality for vehicles. We have proposed a novel monocular HUD system that can set the HUD image to any depth position. The monocular HUD system needs to control the perceived depth position of the display image, thus we have developed a method to control the depth perception position of the display image. In our last report, we described how the depth perception position can be controlled up to 60m by a static display image with monocular depth cues. In this study, we investigated the effectiveness of dynamic depth cues, a head motion parallax method and a dynamic perspective method in the depth perception position of monocular vision. The experimental results show the depth perception position can be controlled up to 120m by dynamic display image.

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We developed a high mobility polycrystalline oxide semiconductor, IGO (Indium Gallium Oxide), which is the crystalline In₂O₃ based random orientation polycrystalline material. The polycrystalline IGO has two unique characteristics. One is the high mobility with a wide window for fabrication process and the property is much stable. The other is the wet etching tolerance which enables the merged photolithography process. In spite of the low temperature process below 300°C, the mobility of polycrystalline IGO TFT was over 20cm²/Vs with the standard deviation smaller than 1cm2/Vs and the shift of the threshold voltage after positive bias temperature stress (Vg=Vd=15V, 10, 000s) was smaller than 0.3V. These results imply that the interruption of carrier conductivity at the grain boundaries of polycrystalline structure can be neglected with respect to the TFT characteristics and the reliability. From these properties, we concluded that the polycrystalline IGO is one of the promising channel materials for the backplane TFT of future OLED displays.

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This paper describes an approach for reproducing illuminant colors and specular highlights on television screens using Color-Mode-Index (CMI), which is a novel evaluation index for color-appearance of reproduced colors. We quantify the lightness of color-mode boundary as CMI 100. We reveal that surface colors in nature scenes should be reproduced under CMI 100 and that the acceptable limit is CMI 110. Then we show that the mode boundary is similar to the optimal color loci. We also reveal that the preferred CMI condition for reproducing illuminant colors and specular highlights is over CMI 100 and that the most preferred condition is CMI 120-150. Then we show the examples for reproducing illuminant colors and specular highlights with realistic impression by controlling color-mode using CMI.

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This paper describes multi-camera technology that generates quad-HD video based on depth information in real time. We propose new high-resolution image synthesis algorithms based on disparity estimation suitable for hardware implementation. Each green camera is shifted by half the length of one pixel with respect to the base camera. Thereby, a quad-HD image is synthesized using a simple pixel matching algorithm. Moreover, the reliability of the disparity estimation is simultaneously evaluated as error information. Experimental results show that quad-HD resolution is obtained. We conclude that our algorithms are effective for high-resolution cameras.

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Novel soluble 5, 12-bis (triisopropyl-silylethynyl) dinaphthothienothiophene (TIPS-DNTT) has been developed for printed Organic Field Effect Transistors (OFETs). TIPS-DNTT is air-stable and OFETs Using TIPSDNTT showed typical p-type FET characteristics. TIPS-DNTT has a solubility of 0.2 wt% in chloroform and 0.1 wt% in toluene at room temperature. OFETs Using TIPS-DNTT were fabricated on silicon substrates by vacuum deposition; their mobility value was 0.4 cm²/Vs. The OFETs on silicon by solution-process under ambient conditions showed mobilities of 0.1 - 0.05 cm²/Vs and a current on/off ratio of 10⁶. Solution processed OFETs on plastic substrates were demonstrated and their mobility exceed 0.01 cm²/Vs.

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This study reports on the synthesis of red phosphorescent, solution processable chain-end functional, mid-chain- and three-arm star polymers from a functionalized styryl monomer host and a RAFT agent containing a tris-cyclometalated Ir(III) complex phosphorescent group (dopant). The polymerization was carried out in toluene at 120°C, and the resulting polymers showed a narrow molecular weight distribution (Ð<1.3) and contained approximately 6-11 mol% of the Ir(piq)₃ complex. All polymers showed good solubility in non-polar organic solvents and exhibited red emission. Of these polymers, the three-arm star polymer showed better energy transfer (in film) compared to the midchain functional and end chain functional polymers. No significant difference in optical properties and energy levels was found for the end functional vs the mid-chain and three-arm star polymers. Preliminary device evaluation of the end functional Ir(piq)₃ poly(host) showed a current efficiency of 0.4 cd/A at 10 mA/cm² and a voltage of 10.5 V with color CIE 1931 coordinate (0.68, 0.31).

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We have been investigating the effect of speech rate alteration on Japanese speech intelligibility, especially the differences caused by phonetic feature. We evaluated this difference in intelligibility using the Japanese Diagnostic Rhyme Test (DRT) on artificially speed-altered speech, such as time-expanded speech (1.6 times the original length, or 60% time expansion) and time-contracted speech (0.6 times the original length). Artificial speaking rate alteration was shown to have some effect or degradation on the Japanese speech intelligibility depending on the phonetic feature, initial consonant feature, and succeeding vowel context. Nasal and voiced affricates were relatively unaffected by speed alteration. Syllables with vowel context /i/ showed 10% higher intelligibility when time-expanded. Furthermore, we showed that the intelligibility was affected by only the time length of the initial consonant by comparing the evaluation results of simple expansion/contraction and phonetic expansion/contraction. These results suggest guidelines for feature-dependent intelligible speed alteration methods.

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We present a fast GPU (graphic processor unit) implementation of super-resolved free-viewpoint image synthesis using lower-resolution multiview images. To speed up the super-resolution reconstruction process, we propose an efficient and compact matrix representation that is suitable for parallelization using a GPU. We also modified the initial image and regularizer for the reconstruction process to reduce the iteration time until convergence. As a result, we achieved a speed up of about 70 times compared to the original CPU-implemented algorithm, requiring only 130 ms for synthesizing a 320×240 pixel free-viewpoint image from 160×120 pixel input images.

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We present a non-photorealistic rendering method for generating stained glass images in which a line drawing is embedded. An input image is decomposed into cells by using a weighted anisotropic Voronoi tessellation on the basis of the distance transform of the input line drawing. Anisotropy and weighting are useful for preserving input lines embedded in stained glass images.

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