Unique monochrome 0.6" CRTs, based on a new gun concept and a phosphor screening method, have been developed. The phosphor screen emits a white cathodoluminescence which has a high brightness of more than 2, 000 cd/m² along with a high resolution of 700 TV lines horizontally and consumes less than 2 watts of power. The tube itself weighs 6 grams, and the total weight of the entire unit, including the CRT, yoke, driver board assembly with socket, is only 30 grams. These units can be utilized wherever brightness, resolution, weight, size, power consumption and price where the major factors for varied applications whether current and in the future.

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It has been found that a phosphor screen, composed of Y₂O₂S: Tb, in 0.6 inches CRT exhibits two distinctively different slopes in voltage dependence curve of the cathodoluminescence excitation; e. g. above and below a 3 keV potential. These difference in the voltage dependence curves of the cathodoluminescence may be attributed to an involvement of a piezoelectricity of the phosphor crystals under irradiation of the electrons.

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Recently, glass blocks are often used for parts of a building wall and are well effective on lighting and decoration. A glass block is originally clear and hollow. If we set a pair of electrodes and pack proper gases in it, we can turn it a discharge tube easily. We packed Hg and Neon in it to make it a multicolored discharge tube and tried to develop a large-sized multicolored display. Although the brightness was not necessarily enough and the luminescent efficiency was low, we could obtain the following good results.
(1) We have formed a display panel with 5×7 dots by 35 blocks and could indicate alphabets and Arabic figures in two colors, red and blue.
(2) The negative glow was covered by the anode of the next block perfectly in a panel with blocks shaped Z.
(3) The negative glow in a square block could be covered too by the blind in front of the cathode.
(4) The luminous color was considerably vivid. That is, the red was (x=0.5, y=0.33) and the blue was (0.22, 0.24).

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Recently, bolt-clamped composite Langevin-type ultrasonic transducers have been developed and manufactured for ultrasonic fish finders as well as ultrasonic cleaners. They are composite vibrators with several piezoelectric elements and metal elements stacked alternatively at proper positions in one arm of the Langevin-type transducers, so that they can generate the ultrasonic power more efficiently compared with conventional Langevin transducers which are operated at their higher harmonic modes.
In this paper, the frequency characteristics of the composite Langevin-type ultrasonic transducers for radiating the ultrasonic power in water are investigated using the transmission line model. The admittance characteristics, the electromechanical coupling factors, and the electroacoustic efficiencies of the transducers are analyzed theoretically and experimentally. Results obtained with a bolt-clamped composite Langevin-type ultrasonic transducer are coincident well with the theoretical results.

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A high resolution of less than 2 nm and high speed response of 25 kHz is realized by an optical beam position sensor with a gold-diffused Pb₂CrO₅ thin film layer. A Pb₂CrO₅ film layer is prepared using an electron beam evaporation deposition technique. Incorporation of thermal diffusion treatment of an evaporated Au layer into the Pb₂CrO₅ film increases drastically the photosensitivity, without degrading the spectral photoresponse characteristics and ratio of photocurrent and dark current. The photo-sensing device has three parallel planar gold electrodes evaporated on tie film surface in a configuration with two narrow electrode gaps. The photocurrent obtained from the central electrode depends lineally upon the light beam position. The device has excellent characteristics of the position sensitivity of 240mV/μm and the linearity deviation of ±1% in the effective measuring range of 40μm. Observation of the surface displacement of a piezoelectric multi-layer actuator is demonstrated by using the photo-sensing device.

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Bridge of semiconductor strain gauges with a silicon diaphragm is very useful for pressure measurement and has currently wide applications for many fields. However, these gauges have miss matchings of resistance and temperature co-efficients. These facts bring difficulties for use in a wide temperature range with high accuracy.
This paper presents the precision and wide range temperature compensation algorithm for semicoductor strain gauge bridge by the analogue circuit technique.
The compensation by an analogue circuit can achieve its purpose with small size of hardware and can produce higher reliabilitiy and lower cost than digital methods. One of the subjects of temperature compensation is to take balance of bridge at several temperature points. The others are to keep sensitivity at constant value against the third order non-linear temperature co-efficients and to eliminate the interference between balance adjustment and balance compensation. These subjects have been achieved without measuring temperature itself.
This temperature compensation method is implemented with good temperature stabilities to mass-produced pressure and differential pressure transmitters of a silicon diaphragm type sensor for industrial use.

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Zirconia oxygen sensors are widely used for automobiles and industrial furnaces. The sensor has an inner volume and two solid electrolyte cells, a pumping cell and a sensing cell. Output current of the sensor is proportional to the diffusing gas speed running through the pin hole which connects the inner volume and gas to be measured. The sensor is suitable to an extended range air-to-fuel ratio sensor which measures air-to-fuel ratio from rich to lean.
Output current of the sensor pulsates with the pressure pulsation of exhaust gas, and the average current shifts with the amplitude of the pressure pulsation, when the sensor is used to measure the air-to-fuel ratio of exhaust gas from an automobile. Dynamic characteristics of the sensor are simulated numerically to clarify the cause of the current pulsation and the shift. A physical model for gas diffusion and gas flow in the pin hole and the inner volume is made, and chemical reaction at electrodes are considered for the calculation. Gas flow and concentration distribution of gasses, and the output current of the sensor are calculated and compared with measured values.
Calculated maximum gas flow rate is 1.0m/sec. in the pin hole and corresponding current shift is 22% which agrees with the measured value. The calculation suggests that the shift of output current decreases as the volume of the inner volume is smaller, and that the shift is negligibly small if the volume is 0.5mm³ or less. A sensor which has the inner volume of 0.15mm³ is made and the effect of pressure pulsation on the output current is measured. The current shift is 1/5 of the shift of conventional oxygen sensors.

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Recently there have been increasing demands for high precise information of humidity. The realization of driving circuit of a humidity sensor to satisfy them have been desired.
We produced a high precise and sensitive driving circuit of a capacitive humidity sensor used both a negative-capacitor-circuit and a capacitance-scaling-circuit on the basis of a Wien bridge oscillator as an experiment.
In detecting small capacitance change, removing unnecessary offset capacitance by the negative-capacitor-circuit leads to increasing capacitance sensitivity. The combined capacitance was amplified up to fit the Wien bridge oscillator by the capacitance-scaling-circuit and we detected a frequency change which the capacitance change converted into through its oscillator.
We investigated three circuits, our proposed new circuit, Wien bridge oscillator, and astable multivibrator one. As a result of experiment, the frequency stability, the capacitance resolution, and the temperature coefficient of a new circuit is -5.6×10^-3, 0.0015pF (at 100pF), and -0.005pF/°C (at 100pF), respectively. These values were improved to be about one order magnitude better than that of the conventional circuits.

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This paper describes a method of improving the resolution and accuracy of incremental type rotary encoders by interpolating the scale pitch interval using the phase encoding and code compensation system. Several interpolation methods have been proposed which stand on the assumption that the scale intervals are accurate. But the experiment on an optical encoder system revealed that the scale pitch intervals include error.
The interpolation method proposed in this paper compensates the error in the pitch intervals as well as the error caused by the nonlinearity of the detected signals. By applying this system to an optical incremental type rotary encoder whose scale pitch is 1/360 rotation (1 degree resolution), finer than 1/45000 rotation (0.008 degree) resolution has been obtained.

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This paper deals with a new integrated measurement system. This system consists of LED displacement sensors and CCD cameras. A spot-light of an LED displacement sensor is used for the active stereo sensing method. Simaltaneously, the outputs of the LED displacement sensors make it is easy to calibrate the camera parameters. Neural networks were employed to compensate such output errors of the vision system, as a camera parameter error, lens distortion and so on. Plural sensory outputs are integrated by a sensor integration system with two antecedents, one of which is the value determined by changes of the sensor output and the sensor position and the other one of which is the environmental data of the sensor. Since these information are vague values, the system is based on fuzzy inference processing. Furthermore in order to fast and accurate sensing, the system is based on an active sensig method, and the system only uses the vision system when the system estimates the LED displacement sensor cannot measure a distance. The effectiveness is verified by some experimental results.

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Recently, many researches have been done to apply neural networks to pattern recognition and various simulation results prove the ability of neural networks. However, compactness, transaction speed, and cost of these products are important design factors when we apply neural networks to commercial products. In this paper, we propose a structure reduction method for neural networks concerning these factors. We adopt a slab-like architecture to the proposed method to extract characteristics of the inputs. By using the random masks, we can avoid the possibility of generating the same slab values even when the inputs are different. First, we show that the structure of a neural network can be systematically reduced by the proposed method for alphabets that are represented as binary data. Then we apply the proposed method to bill money and coin data that are represented by gray levels and show the effectiveness of the proposed method.

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