Koichi Kawata

Inspection machine using laser scanning for chip-mounted circuit boards

This paper deals with the in-line three-dimensional measurement of circuit boards with mounted electronic components. The surface for inspection is scanned by a laser beam, and three-dimensional data are obtained by triangulation from the position of the reflected light measured with a position-sensitive detector (PSD). The location of reflected light is measured from a direction at an angle to the axis of the incident laser beam. The light from the target is reflected by the mirror which is positioned between the f (theta) lens and the target to increase the angle and the measuring sensitivity. The position of the image plane of the reflected beam varies according to the scanning position, which produces a similar effect to the variation of height. The measured value is corrected by a ROM set for three-dimensional space in data processing. The error in height measurement is 0.06 to 0.08 mm, and 0.025 mm accuracy is obtained in the neighboring area of the electronic component targets in practical inspection.

A New Small-Size Magnetic Disc Memory for Still Picture Recording

More and more information may be demanded by people for better living and business. In the area of broadcasting, it would be necessary to offer additional program materials to suite the variety and individuality of home viewers by more efficient and effective communication than conventional ways within limited bandwidth.

Vision sensor system for the environment of disaster

A vision sensor system composed of a CO2 laser. EOM modulator, holographic scanner, infrared detector, and image processor has been developed. The holographic grating disk scanner is composed of ten facets, and each hologram is made of Ge. The maximum diffraction efficiency of 62.9% is achieved. By rotating the holographic grating disk with the number of revolutions (3000 rpm), it is possible to get images in which the resolution is 10 cm within the distance region of 3-30 m.