Kabushiki Kaisha Toshiba

Maki Yoshida

Kazumasa Hirayama

Tatsuya Yamazaki

Shoichi Yokoyama

Tatsuhiko Asaka

The adjustment apparatus automatically adjusts the position and angle of a deflection yoke attached to the neck part of a cathode ray tube. A cathode ray tube having a deflection yoke as an adjustment target attached to its neck part is fixed to a predetermined adjustment position such that its tube axis extends in the horizontal direction. The adjustment apparatus holds a deflection yoke attached to the neck part of the cathode ray tube fixed to an adjustment position by means of a hold mechanism. A test image displayed through a fluorescent surface of the cathode ray tube is picked up by a plurality of cameras. The deflection yoke held by the hold mechanism is moved based on image data picked up by the cameras. The position and angle of the deflection yoke with respect to the neck part are automatically adjusted.

Deflection yoke adjustment apparatus for a cathode ray tube

A laser beam is emitted form one side to a pair of square holes, while an electron gun assembly is being rotated on the tube axis of a color cathode-ray tube. The resulting diffraction pattern is sensed. When diffraction images included in the diffraction pattern are processed and a zero-order diffraction image and at least a first-order diffraction image are sensed in the pattern, the distance between the center of the zero-order diffraction image and the center of the first-order diffraction image is measured. The rotational position at which the distance is the smallest is sensed. The electron gun assembly is rotated to the position and held in place. Consequently, high-speed positioning is done with high rotation accuracy, which helps manufacture high-quality color cathode-ray tubes.

Growing community of inventors

Kita-adachi-gun, Japan

Maki Yoshida