We developed a prototype of a scan-type image capturing system applicable to three-dimensiona (3-D) displays based on one-dimensional integral imaging. The captured 3-D images were free of distortion and composed of high-density rays. Using the auto-stereoscopic display based on the one-dimensional integral imaging method, the synthesized images were successfully reproduced as 3-D images. In addition, we evaluated the image quality of this system by analyzing blur in relation to object depth.

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A new high-density directional (HDD) display using the time-multiplexing technique is proposed to reduce the complexity of the multi-projection system used for the HDD display. The HDD display is a natural three-dimensional display that has been developed to solve the visual fatigue problem caused by the accommodation-vergence conflict. The proposed HDD display consisted of multiple time-multiplexing display modules. Each module consisted of an LED array, a digital micromirror device (DMD), lenses, and an aperture array. A number of directional images were displayed by the DMD at a high frame rate, and the LEDs emitted light one after another in synchronization with the DMD. All directional images were given different horizontal display directions. Each module generated 15 directional images at a frame rate of 60 Hz. Four modules were combined to display 60 directional images in different horizontal directions with an angle pitch of 0.31 degrees.

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We propose a high-resolution and high-frame rate video imaging method in dark conditions. The proposed method consists of two steps. First, we acquired a pair of video sequences that took the same scene with different spatio-temporal resolution. One was a long exposure video sequence with high-resolution and low-frame rate. The other was a short exposure video sequence with low-resolution and high-frame rate. Second, we mutually compensated spatio-temporal information between the two video sequences since the long exposure made motion blurs and the low-resolution imaging made spatial blurs. The compensation was performed by minimization of cost function. Our method significantly reduced those blurs because the lack of information in one video sequence causing such blurs was compensated by the other one. In this paper we show the advantages of our method using both simulation and a prototype camera system.

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We have developed a technique to reduce the chip warpage that results when a large sensor chip is bonded to a board. We performed a structure simulation that included the use of die-bond resins. We improved the die-bonding process, produced a prototype, and tested it. Results showed that it is possible to keep the warpage below 20μm even when a chip over 20 mm long is bonded to a printed circuit board with thermoset die-bond resins. We used our warp control technique to bend a sensor chip in the direction of the field curvature of a photographic lens. With the aim of deploying large sensors in the future, we performed a basic verification test of the tiling technique used to align multiple chips in a plane, developed a chip connection technique, and identified potential problems that could hamper the practical use of both.

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