The idea of vision chip is integrating photodetectors with processors on a VLSI. Vision chips are expected to provide many advantages compared with conventional vision systems. These include high speed, small size, low power consumption, wide brightness range, and low-cost. This paper proposes a motion measurement method for pixel-parallel vision chips. The method reports one-dimensional motion vector of local motion on a focal plane with three photodetectors. The method detects the motion from a relation of two binary signals each of which represents the existence of a spatial edge between adjacent photodetectors. Computer simulation at an image processing level showed that the method detects the motion accurately in wide speed range. The method has been implemented on an experimental vision chip using standard CMOS process and confirmed that the chip stably detects the motion by experiments.

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A human retina like, wide operating-range CMOS image sensor with pixels that shift their intensity-response curves according to the intensity of light has been constructed. The chip realizes an operating range 28dB wider than that of conventional CMOS image sensor. The chip integrates 128×128 pixels whose size is 24×24μm² with 0.8μm single poly-Si and double metal CMOS technology. The chip size is 6.0×4.6mm².

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A digital LSI circuit for learning and odor recognition using 1bit-stream data processing method is proposed. The output pattern of QCM sensor array is measured and is classified by the circuit based upon LVQ algorithm. Only small amount of circuit and wires are required when 1-bit data processing method is adopted. The whole circuit was realized utilizing FPGA, and odor recognition was successfully performed.

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Catheterization used for the minimally invasive therapy requires a real time information about position and orientation of a catheter tip for navigation. It has been necessary to use X-ray radioscopy to image the catheter in a blood vessel. In this paper, a simple sensor system for detecting the position and orientation utilizing earth magnetic field and AC (10kHz) magnetic field generated by a two-axis source coil is proposed. Real time information about the position and orientation and map of blood vessels make the navigation possible. The map can be obtained in advance using X-ray CT or MRI. A three-axis MI sensor (Magneto-Impedance effect sensor) for measuring earth magnetic field and AC magnetic field is mounted on the catheter tip. The sensor signal is used to calculate the position and orientation in a computer. On the display, a figure of the catheter is superimposed on the map of the blood vessel. Detecting position and orientation using this sensor system was succeeded.

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In order to apply Giant Magneto-Resistive (GMR) elements to revolution sensors for automobiles, we studied an annealing effect upon GMR elements. After the GMR elements were annealed with the optimized condition, they showed sufficient temperature stability for automobile applications, as well as large MR ratio. The GMR elements were integrated with a sensing processing IC without any damage during the GMR wafer process. Sensitive sensor properties were obtained, especially the repeatability was three times better than that of a semiconductor Hall revolution sensor, which was due to that the integration of the GMR element with IC prevented noise and the signal output of the GMR element was one order higher than that of the semiconductor Hall revolution sensor.

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A CMOS optical sensor which measures the number and the size of objects has been designed and successfully tested. The sensor contains an array of 24×14 pixels in a chip area of 6.8mm×4.6mm. The sensor first performs image digitization by comparing a photogenerated current with a given threshold. A Winner-Take-All (WTA) operation is carried out next in each object region which is defined as a collection of illuminated pixels mutually connected in either a horizontal or a vertical direction. Realization of the WTA circuit with sharp selectivity makes it possible to select only one winner from each object by utilizing inherent mismatch in transistor characteristics. The output current of the winning pixel represents the object size; the number of winning pixels represents the number of objects. The use of an analog WTA circuit contributed to simple implementation. The sensor operated successfully for images in which the sizes of objects were equal to or smaller than 4×4 pixels.

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We have fabricated a CMOS optical sensor which detects linestops for the edges of four orientations and the corners of an input image. The sensor measures 6.8mm×6.9mm and contains an array of 11×11 pixels. Each pixel consists of phototransistors, an orientation sensor, four memory units, and a spatial filtering unit (SFU). The phototransistor is shared among four adjacent pixels. The sensor first decomposes an input image into four orientations (0deg, 45deg, 90deg, 135deg) by an array of orientation sensors. Each orientation sensor determines the local orientation according to the illumination pattern on phototransistors located at the four corners of a pixel. The SFU and the memory units perform a series of spatial filtering far each of these orientations to detect the image features. Spatial filtering is realized by convolution and threshold operations. Selection of convolution kernel and threshold determines which of the following filtering functions is performed: line completion, elimination of isolated points, line elongation, or linestop detection. Convolution is realized by a current mirror circuit, Experimental results show that the sensor is fully functional and the processing time to detect these features is about 200μsec.

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This paper presents an architecture for parallel image processing that breaks the bottleneck of data transfer between an image sensor, memories and functional units. By employing an integrated image sensor, parallel data transfer between the sensor and memories can be achieved. Moreover, for parallel memory access, an optimal memory allocation is proposed that maps pixels to be accessed in parallel onto different memory modules. A functional unit allocation for local communication is also proposed to minimize the complexity of the interconnection network between memories and functional units.

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Sticking is a fundamental phenomenon on micromachined devices or tructures. This paper describes about a practical and successful method of prevention for micromachined resonators from sticking and estimation of its sticking resistance based on experimental data.

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Display characteristics of color displays using the Fabry-Perot interferometer (FPI) whose cavity length is controllable were analyzed theoretically. Transmission and reflection type displays with the structure of FPI-color filter (red, green and blue)-white light source and transmission type one with the structure of FPI-color filter-three band spectrum fluorescent lamp were studied. The last type of display was expected to have higher contrast and more bright display compared with the other two types.

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