This paper presents a high-sensitivity camera tube for Hi-Vision, formed by combining a new 2/3-inch MS system with the HARP (High-gain Avalanche Rushing amorphous Photoconductor) target. Numerical analysis of electron trajectories and experimental results leads to the following new fundamental design concepts. (1) Making the anode surface opposite the cathode in convex form reduces the power dissipation at the anode. (2) By applying a twist to the DEFLECTRON on the target side from its mid-point and by using a ring electrode of suitable length, the beam landing characteristics and the resolution in the picture corners can be improved. These concepts were successfully implemented in a new tube ten times as sensitive as Saticon tubes. The amplitude response is 29 % at 800 TV lines in the ITE AR chart. Resolution is uniform over the entire picture area, with no sacrifice in lag or shading.

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This paper describes the development of a programming environment supporting input in graphic form to improve the efficiency of transforming new algorithm concepts into a code set executable on a multiprocessor architecture. The user draws a signal flowgraph on the screen as if using a notepad. The system translates it into a form which can be executed on the Picot system, a multiprocessor system for processing video signals in real time. The new system, named PicPEn, consists mainly of a user-friendly graphics editor and an integrated compiler which breaks up the signal flowgraph, compensates for timing differences between processing nodes, and generates the machine code for each processor.

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Since a MUSE signal is a Pulse Amplitude Modulation signal, waveform distortion is converted to discrete distortions due to sampling by the MUSE decoder. These discrete distortion can be regarded as a multiple echoes. On the other hand, the relationship between picture quality and a single echo in a television signal can be described by a logistic function.
In this paper, a rating function which can be used to describe degree of impairment due to multiple echoes is developed by application of the logistic function. It was confirmed through subjective assessment tests that the rating function can be used for the distortion of a MUSE signal. The frequency characteristics required for MUSE signal transmission were derived by using the rating function.

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A matrix-driven electron source essential for a large high-definition MDS flat-panel CRT has been developed. This electron source consists of twe parts, triode with a vertically extended line cathode and two grids, and switching electrodes for vertical scanning by an electron beam emitted by the line cathodes. This structure allows a high emission current with a low voltage modulation signal. Driving circuits and the structures of the grids are simplified by a new driving method in which a modulation signal is applied to directly-heated type line cathodes instead of grids. Beam current from each segment of the electron source is made uniform by a newly-developed correction circuit which equalizes the cut-off voltages of each segment.

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A braille translation system for translating book (KANJI-KANA) sentences into braille sentences using a personal computer is described. The braille translation consists of two processes. (1) KANJI (ideographic) characters are replaced by KANA (phonetic) characters (articulation). (2) KANA notation corresponds to braille notation. The lowest BUNSETSU number method in the morphological analysis of Japanese sentences is used in the process (1). In this process (2), the spaces are left between words and long vowel sounds are replaced by long vowel sound symbols. This system has two advantages, (1) easy correction of incorrect results and (2) low cost for personal use.

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In intercarrier demodulation in TV sound multiplexing, video signals affect sound subchannels and degrade both buzz-beat and S/buzz characteristics. To improve these characteristics, the authors analyzed the influence of Nyquist-filter and multipath propagation on the intercarrier demodulation by demonstrating a method of buzz waveform calculation. They reached conclusions as follow.
(1) Both buzz-best and S/buzz ratios caused by Nyquist-filter are smaller than allowed values, but buzz-beat is close to its allowed value.
(2) The mechanism of multipath degradation is similar to that of Nyquist-filter.
(3) The degree of multipath degradation can be estimated with the product [α·τ].
(α : Inverse ratio of D/U, τ : Delay time)

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[in Japanese]

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