As CRTs have become larger, there has been an increasing demand for higher quality reproduced images from consumer VCRs that record FM signals. It is well known that the SNR is improved without deterioration of frequency response by using an equalizer to emphasize the lower sidebands or to suppress the upper sidebands of playback FM signals. However, a type of noise which appears as signal inversion is generated at black-to-white transitions. The SNR is therefore compromised by using a conventional equalizer to maintain the inversion margin. These equalizers have fixed characteristics, even for images without the transitions that cause signal inversions. We have applied digital signal processing technology to develop a dynamic equalizer that selects the optimum from among several equalizer functions at each sampling point, according to the state of the playback FM signal. Simulations have confirmed the improvement in SNR without causing inversions.

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This paper proposes a new cut-detection algorithm for image sequences. The new method is based on image segmantation and classification of the regions resulting from the segmentation. Each region is assigned to a class that terminates at a shot boundary. This technique is shown to be effective for gradual shot transitions, where conventional cut-detection algorithms are known to fail. It is also shown that the threshold with which the outputs of the cut detector are compared can be selected easily as the outputs are close to unity at cuts, while low elsewhere. The effectiveness of the proposed algorithm is demonstrated by experiments.

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A cathode composed of LaB₆, and BaAl₂O₄ and a discharge cell without mercury have been developed for a long life DC plasma displey (PDP). The cathode material is plated on the cathode by the plasma-flame technique. The composition of the discharge cell and cathode emitter material of the newly developed long-life PDP are reported. The decay characteristics of the PDP panel luminance are also tested for 25, 000 hours. The discharge conditions, such as filling gas, gas pressure and discharge current are used as testing parameters. It is shown that the new cathode composed of LaB₆ and BaAl₂O₄ is sufficiently strong for cathode sputtering, which determines the life-time of the DC PDP.

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An investigation of the application of alkaline-earth-metal and rare-earth-element complexing oxide powders for the screen-printed protective layer of AC-PDPs is reported. The materials show higher luminous efficiency than conventional MgO. The role of the rare-earth-elements is significant and powders containing La showed the highest luminous efficiency, followed in order by those containing Y and Gd. The alkaline-earth-metals little effect. Protective layers containing BaLa₂O₄ powders showed the lowest discharge voltage. Addition of a binder, a precursor of complexing oxide and modification by heat treatment, lowers the sustaining voltage and raises the luminous efficiency. It is concluded that the complexing oxide powders show high potential as the screen-printed protective layer and finer powder is necessary for improving the discharge characteristics and ensuring long-time operation.

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This paper deals with a new shape measuring system for factory automation applications, specifically data collection for inventory and management control, and process or machine control for improving manufacturing productivity. This inspection system combines a high-speed shape measuring system with a real-time Hough transform system. It can judge whether or not a shape has been determined previously. It is, especially, useful for moving objects on belt conveyers, because the system can make the shape measurement quickly, without stopping conveyer. Memory capacity for only one scanning line is required in this system, because of the features of the algorithm. In addition to high-speed processing, the system algorithm is suitable for the configuration of hardware because of its simplicity. It is confirmed that the system can measure the perimeter length, shape factors and position of contour lines quickly and accurately.

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We propose a bandwidth limiting type spread spectrum communication for application to development of frequency resources. First, we estimate the effect of bandwidth limiting, and evaluate the possibility of frequency-division multiplexing. Second, to reduce interference in existing signals, we estimate their susceptibility to interference by using a trapfilter circuit. Third, majority decision logic is proposed to realize amplitude limiting type code-division multiplexing easily. Our results confirm the effectiveness of this method.

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A display system requiring no special glasses is a useful technology for three-dimensional (3-D) images. The lenticular display system has such demerits as having a non-planer screen and blurred images. In this paper, a newly developed, 3-D real-time display with a holographic optical element (HOE) is described. This simple 3-D display can avoid problems of lenticular systems. The advantage of the screen HOE is that the number of presented views is much greater that of an equivalent lenticular display, because the screen HOE can multiplex pixels both horizontally and vertically to display lateral views. This screen HOE can be made more easily and smoothly than an electron beam recording. The trial screen HOE is 4“×5” and consists of 128, 000 holograms. Therefore, the image size measures approximately 4“× 5”, and the resolution is 200×160 pixels×4 views.

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[in Japanese]

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