This paper proposes a CMOS image sensor with high-speed non-destructive image sensing mode using bidirectional multiple charge transfer active pixels. The proposed image sensor is suitable for low-power focal plane motion vector estimation using iterative block matching while maintaining the image quality of video-rate (33ms/frame) pictures and the accuracy of the motion vector estimation. The performances of the bidirectional multiple charge transfer active pixel sensor are evaluated by circuit simulations and the proper operation of the sensor is confirmed by experiments.

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This paper describes the analysis of magnetic patterns of a moving object such as a car. The variation of the magnetic field intensity has been observed by using a flux-gate magnetometer which is set beside a road. We have experimentally measured the magnetic field intensity distribution. The results of the observed data have been perceived and classified into six typical magnetic patterns. A theoretical method to calculate the magnetic patterns also has been predetermined. Eight magnetic patterns were calculated of a simple magnetic dipole field for various magnetic bias angles B and more two magnetic patterns have been estimated over experimental method in which only six magnetic patterns were detected.
The reason of this disparity in the results is that there are some apparently difficulties in calculating the magnetic pattern with magnetic bias angles of B=90° and B=270° over the experimental method because of the shape of the object which has been chosen.

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There are various researches on a tin oxide gas sensor. It is effective to adopt the various information in an indoor environment. The information is derived from the sensor output characteristics. And, it is also understood that the sensor output is influenced by the indoor climate. The purpose of this research is to clarify the influence of the temperature, humidity and the atmospheric pressure to the gas sensor output. However, the fluctuation of the base level of the sensor output every day is considerably large. So, it is difficult to introduce directly some information from the sensor level. It is attempted to characterize the variance by smoothing the sensor output using the moving average method. As for results, a strong correlation coefficient presents between the sensor output and the atmospheric pressure. This result can be applied to predict a sensor output. The sensor output is derived roughly using an approximate equation, which is introduced by the trigonometric function. The predicted value, however, does not have good accuracy in summer and winter. A theory of Markov source is used to predict an accurate gas sensor output still more. The Markov prediction value is good at an actual sensor output in summer. Both methods are very effective to predict an indoor thermal indexes using tin oxide gas sensor.

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Several daily human-behaviors are identified using plural odor-sensor arrays. This study was done to investigate a survey system for the aged who lived in solitude. Human beings occur various odors in their household life. The odors can be classified into two fields, namely occur from a body and occur by a vital action in a domestic environment. The concentration of the former odor is very low. The odor that generates at preparing a meal belongs to the latter, and it is comparatively high concentration. Sleeping, having a meal and awakening which are basic human behaviors can be identified using plural odor-sensor arrays. These array outputs are characterized using 2-D, 3-D graphs are also useful. As for the results, it becomes obvious that several basic indoor human behaviors can be identified by the plot-places of the sensor-array characteristics. The characteristics are caused by sensor sensitivities and odor concentrations that depend on human behaviors. This system is useful for the invasion of privacy of the occupant.

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Influence of impulity concentration on behavior of a semiconductor electrostatic actuator in low frequency drive voltage has been analyzed theoretically. The actuator has a p-type silicon movable electrode supported by cantilever beams and a metal fixed electrode opposing to the movable one. When gap width between the electrodes is fixed, capacitance between them changes depending on the drive voltage and rate of the change increases with decrease of the concentration N_a (15% in N_a=10¹⁴cm^-3 and 0.3%in N_a=10¹⁸cm^-3). For Na<10¹⁶cm^-3, pull-in voltage and release voltage of displacement-voltage curves increases with decrease of the concentration, especially when positive voltage is applied to the fixed electrode. For N_a>10¹⁶cm^-3, the impulity concentration has almost no influences on the behavior of the actuator independent of the polarity of the drive voltage.

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A systematic survey to realize high sensitivity of a limiting current type hydrocarbon (HC) sensor with two inner electrodes has been made. The characteristics of electrodes were examined for various electrode materials of sensors with one or two cathodes in a room which was constructed with an yttria stabilized zirconia pellet and a cover with a pinhole. From these examinations, the sensor having two inner electrodes Pt-Ag and an outer electrode Au was expected to have the highest sensitivity. This expectation was confirmed by an examination after constructing an actual sensor.

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This paper describes development of an electric current sensor for measuring a large current. A magnetic saturatable detector is used in place of a Hall detector in the conventional current sensor. The sensor is developed with low price and high stability for parameter deviations caused on a temperature variation and such a disturbance. The balanced large current driving circuit which excites a magnetic detector with very low offset voltage and some techniques are proposed as new circuits which detect the inductance changes caused on a magnetic flux. These sensing circuits realize a stable step for a large current.

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Microstructures with sub-micron widths and gaps (lines and spaces) can be applied to practical and high performance MEMS devices. In the sub-micron LIGA process, one of the most crucial considerations is the fabrication of an X-ray mask with thick X-ray absorbers having sub-micron width. An X-ray mask, which is composed of 1μm-thick Au with a 0.6μm line width and a 0.2μm space as absorbers, 2μm-thick SiC with 240MPa of tensile stress as a membrane and 625μm-thick Si as a frame, was fabricated. As a result of the sub-micron LIGA process, a sub-micron PMMA structure with a maximum aspect ratio of 85, corresponding to 0.2μm minimum width, 6μm length and 17μm height, and sub-micron Ni structures with a maximum aspect ratio of 75, corresponding to 0.2μm minimum width and 15μm height, were fabricated.

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