Organic photosensors were investigated by using x-type metal free phthalocyanine(x-H₂Pc) photoconductor. The desired values of some properties in the photosensor of 200dpi(dot per inch) resolution linear imagesensor for facsimile were examined. The photosensor comprising of Pb electrode of low workfunction metal which is in contact with the x-H₂Pc layer was recognized to be Schottky barrier. The relative darkcurrent of photosensors with Pb electrode of Schottky barrier and Au electrode (high workfunction metal) of ohmic contact were measured.
The darkcurrent value of Pb electrode was reduced by about 10³ than that of Au electrode. The highest photoresponse time was observed by Pb electrode photosensor. It was clarified that the photoresponse times depended on the workfunction of electrode metals of the photosensor.
Photocurrent property of the photosensor with the Pb electrode of low workfunction indicated ohmic current, while the photocurrent of the photosensor with the Au electrode of high workfunction indicated space charge limited current. The results of photocurrent (1.1×10^-6A), photo-to-dark current ratio (7×10⁴), photoresponse rise time(0.6ms) and decay time (0.9ms) were obtained by constructing the photosensor, ITO/x-H₂Pc/Pb These results may be used for linear imagesensor of 200dpi.

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This paper presents a mechanism and driving method of an Inertial Driven Micromanipulator. This micromanipulator utilizes our proposed Bending and Expanding Motion Actuator (BEMA). It provides both fine and coarse motion. Static bending and expanding motion of the BEMA realizes the flexible fine motion, and dynamic motion of the BEMA realizes the coarse motion. Thus, our micromanipulator has a wide dynamic range (±90 degree) and a high resolution (less than 10nm) with a simple mechanism. And this paper proposes fundamental principle of driving method for high speed motion. That is, controlling the impact timing against vibration of ineratial mass realizes the high speed motion of micromanipulator. We tested this driving method by experiment and simulation of sawtooth wave drive and pulse wave drive. And the results of it, new sawtooth wave driving method with controll of impact timing gives 2.0 times of motion speed than conventional method(without control of impact timing). Furthermore, new pulse wave driving method with controll of impact timing gives 5 times motion speed than conventional method.

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The deposition and processing of thin film Shape Memory Alloy (SMA) is presented. By using sputterdeposition technique, 8 to 10μm thick films of TiNi were deposited. Among the features of the thin film SMA, the following can be noticed: large recovery strain; the relation between recovery strain and electrical resistance change of the TiNi alloy, allowing to use the TiNi as a position sensing element; long lifetime; large force-displacement product; high power-weight ratio; simple structural design; and low voltage operation. Therefore, a SMA two way loop actuator as well as a XY stage have been realized. Lift off technique is used to obtain the desired shape of two SMA microactuators. Two SMA cantilevers were folded up from the substrate and bound each other, making a three-dimensional loop. By activating each lever alternately, a SMA two-way actuator was realized. The dimensions of the loop actuator were 2mm in length and 600μm in height. The loop actuator has been successfully operated. It features repeatable motion up to 20Hz and maximum displacement of 300μm at 1Hz.

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Current-voltage characteristics of semiconductive oxides have been investigated in air and in H₂ balanced with air at elevated temperatures. A shift in breakdown voltage to a high electric field was observed for Cr₂O₃, which is a typical p-type semiconductor, upon exposure to H₂, while n-type semiconductors exhibited a reverse shift in breakdown voltage. Among oxide specimens, Nb₂O₅ was found to be the most excellent candidate for a varistor-type sensor, being accompanied with high H₂ sensitivity, excellent mechanical strength and good resistance to high electric field. Further investigations have revealed that the H₂ sensing properties of Nb₂O5 could be improved by 1.0mol% Bi₂O₃ doping. Newly formed Bi₂Nb₁₀O₂₈ phase was suggested to play an important role in enhancing breakdown voltage in air and then the H₂ sensitivity.

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Some research groups studied how to evaluate the human olfaction objectively. But there was no attempt to evaluate objectively a subjectivity evoked by an odor stimulation. We tried to evaluate the feeling of subject, namely subjectivity evoked by the odor stimulation. In this study, we have measured an EEG activity of a subject who was stimulated by the odor and we have evaluated objectively the influence of the odor stimulation by a chaotic analysis and a frequency analysis. We could get the affection of odor stimulation even if the subject did not consciously feel the odor. The results showed that in the favorite odor stimulation the chaotic value of EEG data decreased slowly but it of the unfavorite odor stimulation dispersed. We could measure the change of the feeling of subject by the odor stimulation and we could predict the feeling of subject by several explanatory variates selected from physiological information.

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A CMOS capacitance detection integrated circuit for silicon capacitive sensors has been developed using PLL configuration. The circuit is composed of two voltage controlled capacitance to frequency converters, a phase sensitive detector, a charge pump and a low pass filter. The circuit has differential configuration in order to supress the circuit power suply dependence and temperature dependence. The circuit is also desiged to be able to calibrate variations of the sensor sensitivity and offset with feedback principle. The circuit was designed with SPICE simulator and fabricated with standared CMOS technology of Toyohashi University of Technology. From the measurment result, the sensitivity and offset can be calibrated with applied bias voltage, and the power supply dependence and temperature dependence of the circuit were neally zero, The circuit is considerd as candidate of detection circuit for surface micromaching capacitve sensors.

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