Atsufumi UEKI Shunsuke KOBAYASHI
The requirements which are necessitated for high-resolution full-color display are reviewed. CRTs are achieving almost all of these requirements but size and weight. Real flat displays having good cost and performance are expected in future.
Several types of Ne-orange monochrome plasma display panels (PDPs) of the 10-inch class with a pixel number equivalent to similar size CRTs have been developed, each with its own simple structure and good performance, and put on the market for personal computer terminals. Development of color DC-PDPs has progressed in terms of color reproduction, display panel size, high speed addressing for TV display with a sufficient number of gray levels, luminance and luminous efficiency. AC-PDPs have also resumed active development of color displays in several surface-discharge panel structures. Some recent topics in these developments are reviewed.
Recently, thin film electroluminescent (TFEL) technology has made great progress in the development of multi-color display panels. In this paper, first, the state of the art in TFEL display devices is reviewed. Second, the characteristics of various kinds of color emitting materials are discussed, and present thin film deposition techniques and multi-color picture element composition methods are outlined. Third, the limitations of large capacity color EL displays based on signal pulse retardation are discussed, and then it is shown that a panel with up to approximately 1000 scanning lines can be realized by using mainly higher conductive transparent electrode materials and others. Finally, the future prospects of TFEL display devices for full color EL displays and associated problems are also mentioned.
This paper discusses the present state and future prospects of directly addressed matrix liquid crystal display panels in which a thin film transistor switch matrix is not used.
This paper describes status and trends in regard to resolution, large size panel, color display characteristics and related technologies for active-matrix addressed LCDs, especially, TFT-LCDs from a viewpoint of a high-definition and full-color display. The TFT-LCD is a most promising candidate for it.
Recently, active matrix liquid crystal (LC) displays have been intensively investigated for realizing full color television sets. In order to obtain a high quality picture LC-TV, the color filter is important. Various processes for manufacturing color filters have been studied, such as dispersion, dyeing, printing, electrodeposition, color vacuum evaporation, multilayer interference film, sublimation transfer, photographic coloration, electrophotography, tinted polymer polymerization, and complex processes (combinations of two or more processes). Of these processes, the dispersion, dyeing, and printing processes, which are considered particularly promising, shall be discussed below.
The authors found that the coloration in appearance as a noticeable defect of super twisted nematic LCD (STN-LCD) can be cancelled out and monochromatic display can be realized by adding an optical compensator to the STN-LCD. This NTN mode display shows the steepness of threshold characteristic and the response times equivalent to those in STN, but its contrast ratio, viewing angle, and multiplex driving capability are far better than those in STN. A liquid crystal cell is used as a compensator. Monochromatic display can be done when both display cell and compensator cell satisfy the following three conditions. (1) Product values
Hideki TSUSHIMA Shinya SASAKI Ryoji TAKEYARI Minoru MAEDA
Novel optical FSK modulation/demodulation schemes with AMI coding are proposed to overcome degradation due to the non-uniform frequency modulation characteristic of DFB lasers. It is shown that an NRZ signal can be demodulated without a decoder as opposed to other coding schemes proposed earlier.
Fumio KOYAMA Susumu KINOSHITA Kenichi IGA
This is the first report on room temperature CW operation of GaAlAs/GaAs vertical Fabry-Perot cavity surface emitting lasers. A vertical microcavity was formed with a diameter of 7 µm and cavity length of 5.5 µm by a two-step MOCVD growth and fully monolithic technology. The threshold current was 32 mA under CW condition at 22.5
Mohsen GHAMESHLU Noriyoshi YOSHIDA
The cost trade-off between the number of additional vias employed and the number of layers decreased in Ref.(2) is discussed. We present a cost model and show that the technique in Ref.(2) really reduce the total cost for producing the board.
Yukihiro ARAI Takeshi AGUI Masayuki NAKAJIMA
The sequence of 8-point DCT and scalar quantization is effective in image data compression. The operation is executed very efficiently, if the DCT coefficients need not to be found explicitly. The present paper proposes a method, requiring only five times of multiplication for the transform. The 8-point DCT can be comopsed from the 16-point DFT which gives only the real parts of coefficients, and final scaling. The real part DFT can be implemented by the small FFT Winograd algorithm, which requires only five multiplications. The final scaling can be combined with the quantizing matrix without any change in arithmetic complexity of the qunatizer. Since each signal path in the proposed algorithm has one multiplication at most, the five multiplications can be executed in parallel. This will make the hardware implementation of the algorithm effective.
Mitsuo OHTA Kazutatsu HATAKEYAMA Kiminobu NISHIMURA
Generally speaking, in the actual situation of evaluating or predicting the stochastic random phenomena, it is sometimes inevitable to consider the undesirable modelling error generated from an incomplete situation in the actual measurement (i.e., the observations in an actual environmental field are very often given under the unsatisfactory situation without keeping the idealized physical property assumed abstractively in the theoretical research), together with the inevitable additional background noise of arbitrary distribution type. Thus, the unified statistical treatment for the resultant data contaminated by these additional noises of different type is newly proposed in this paper from the system-theoretical viewpoint closely related to environmental field, based on Bayes' theorem and the information criterion. Its computer-aided identification algorithm is derived in a very compact form matched to the recurrence processing of succesive observations. Finally, the validity and the effectiveness of our theoretical result are experimentally confirmed through the application to the actual data of environmental noise in room acoustics.
Ake CHAISAWADI Tsuoshi TAKEBE Toyoji MATSUMOTO Kiyoshi NISHIKAWA
Two design methods, namely method 1 and method 2, for class
A novel interpretation is given to the information-theoretic meaning of Fano's inequality from the viewpoint of the rate-risk function which expresses the relationship between information rate of observed data and Bayes risk in a decision making context.
Yukiko KONDO Li HU Yoichi FUJII
Electro-optic constants of single-mode proton-exchanged slab waveguiding layers fabricated on z-cut LiNbO3 crystals are estimated, taking into account the field distribution of the propagating TM0 mode.
A high speed tunnel current measurement technique called HSTCM has been proposed for characterizing insulating thin films. A voltage pulse (less than 100 µs) is applied across an insulator and a current pulse is measured using a specially devised operational amplifier. This technique enables measurement of high electric field current to voltage (I-V) characteristics of thin SiO2 films in electric fields up to 2 GV/m, and to measure time dependent tunnel current characteristics in insulators, such as a Si3N4-SiO2 two-layer insulator of an MNOS (Metal Nitride Oxide Semiconductor) device, in the 10 µs-1 ms range. Accurate high electric field I-V characteristics in thin SiO2, and a capacitor coupled model for a floating gate non-volatile memory device could provide a high-precision simulation program for write/erase characteristics for the memory device. Furthermore, high speed time-dependent tunnel current measurement enables characterization of transient carrier trap phenomena in the insulator of the MNOS device in the µs range, i.e., the device's actual operation period. As described above, the HSTCM technique is a strong tool for evaluating tunneling phenomena in various insulating films and the operation of non-volatile memory devices.
In this paper we give a method of transforming logic programs into equational dataflow programs. The equational dataflow program is a set of recursion equations as to variables over a sequence domain. A recursion equation corresponds to each definite (Horn) clause which is interpreted as a transformation of variables to a variable. Each variable denotes a function from the set of natural numbers to the Herbrand base, that is, a sequence of ground atoms. The fair merge function is necessary to realize OR-nondeterminism, which is essential in the deductions of logic programs, by means of an equational dataflow program. The nondeterminism in the transformation caused by a definite clause is eliminated and ensured fair by introducing a kind of oracle which will also be provided by simple recursion equations. Then it will be shown that the equational dataflow program with the oracle is both sound and complete in denoting the finite computation of the original logic program. The semantics of the equational dataflow program is given by fixpoint approach and is interpreted as a semantics of the given logic program.
Hiroshi OHTERA Shigeru YAMADA Hiroyuki NARIHISA
This paper discusses an optimal software release problem, based on a software reliability growth model incorporating the time-dependent behavior of testing-effort expenditures in the software testing. The problem presents an optimum release time when to stop testing and to be ready for release to the user. In particular, we consider a penalty cost due to delay in the scheduled software delivery time. Using a testing-effort function described a Weibull curve, a software reliability growth process in the error detection phenomenon in software testing is modeled based on a nonhomogeneous Poisson process. The testing-effort parameters and the reliability growth parameters in the model are estimated by a modified least-squares estimation and by a maximum-likelihood estimation, respectively. Based on the software reliability growth mode, the optimal software release problem is formulated by using the total expected software cost to be minimized. Further, numerical examples are presented for illustrations.
We have implemented a program editor for Modula-2 at ETH Zurich, named Macpeth. Macpeth is running on Lilith, Macintosh and other machines. We show the data structure for translation from the internal parse tree to the external textual representation. The data structure keeps the information for efficient scrolling and partial refreshing operations on the window.