Mitsubishi Denki Kabushiki Kaisha

Hiroaki Tobuse

Akio Yoshida

Hidenobu Murakami

Hiroshi Koizumi

Shigeo Sasaki

Susumu Hoshinouchi

Kazuo Yoshida

Takuji Oda

Yoshimi Kinoshita

Minoru Kobayashi

Akinobu Kawazu

Tomoyuki Kanda

Tatsunori Hibara

Takashi Ishii

Yasushi Hisaoka

Yoshio Yamane

Masashi Kamio

Masaaki Kinoshita

Yasusi Hisaoka

Ryuji Ueda

Akihiko Yamasaki

Toshiaki Fukunishi

Tadayoshi Owaki

In a color cathode-ray tube, only a foreign matter adhering to a shadow mask is removed effectively without thermal deformation of the shadow mask or thermal denaturation of phosphors. An electron beam produced by an electron gun incorporated in a cathode-ray tube itself is scanned or irradiated to all over a shadow mask of the color cathode-ray tube. The radiant state of a fluorescent screen at this stage is checked to detect a foreign matter adhering to the shadow mask. The electron beam is deflected to align with the position at which the foreign matter is detected, and then irradiated to the foreign matter in the form of pulses. Thus, the foreign matter is heated and removed.

Method and apparatus for removing foreign matters from a cathode-ray tube

An inspection method and an inspection apparatus for the component members of the cathode-ray tube are disclosed. An inspection apparatus composed of normal members other than an object of inspection is prepared at the time of inspecting the phosphor screen of the screen panel, the electron gun or the shadow-mask constituting the cathode-ray tube. In advanced to assembling the cathode-ray tube, the object of inspection is mounted on the inspection apparatus, so that the conformance or rejection of the object of inspection is decided from the illuminated condition of the phosphor screen by irradiating electron beams thereon.

Method of inspection for cathode-ray tube component members and

A fluorescence pattern forming method and apparatus includes electron beams being irradiated over a face panel, on which a fluorescence layer is formed, to form a fluorescence pattern on a color CRT. The fluorescence layer is formed by coating a slurry of fluorescence substance. According to predetermined pattern designing data, a control device causes the electron beams to be irradiated over the fluorescence layer on the face panel so that the fluorescence luminesces. This luminescence is detected by a light detector located on the convex side of the face panel. A correcting device gives a correcting signal to the control device to correct the irradiated position according to the detected light quantity.

Method and apparatus for forming patterns of fluorescence on a color CRT

Printing pattern information from a printing pattern CAD is converted and output as deflection scanning data for the X-axis and the Y-axis by a deflection scanning data generating means. An electron beam deflection scanning means executes deflection scanning by an electron beam on a circuit printing base on the basis of the output deflection scanning data. The printing pattern irradiated with the electron beam is input to a bit map memory by dots which correspond to the points which are irradiated with the electron beam. A radiation control means can ascertain whether or not the point which is to be irradiated with the electron beam has already been subjected to beam irradiation at real time by consecutively reading out the dot information in the bit map memory at the address corresponding to the deflection scanning data. If there is no dot, a dot is written in the bit map memory simultaneously with beam irradiation, while if there is a dot, a blanking means outputs a control signal for cutting off the electron beam. Thus, overlap in printing pattern is detected at real time, thereby ensuring the avoidance of multiple beam radiation, namely, multiple exposure.

Electron beam direct printing apparatus

An electron beam direct drawing device for use in manufacturing a printed circuit board having a photoresist thereon according to a drawing pattern information obtained by a computer aided printed circuit board pattern design, comprises means for dividing the drawing pattern information over a whole area of the printed circuit board into a plurality of fields each capable of being scanned by electron beam and for re-editing drawing patterns of the respective fields, means for storing the divided and then re-edited drawing pattern information, means for generating a first control signal for reading out the stored drawing pattern information sequentially and performing a main deflection of electron beam by means of a main deflector and means for generating a second control signal for deriving, from the stored drawing pattern information, information assigning an orientation of a pattern to be drawn and a scan width of a sub-deflection and for performing a predetermined sub-deflection scanning by means of a sub-deflector, whereby electron beam scans the printed circuit board under a control of a combination of the main deflection and the sub-deflection. A clock generator capable of producing a plurality of clock signals each corresponding to a specific line width of the pattern is provided to expose the line with electron beam of optimum dose.

Electron beam direct drawing device

Growing community of inventors

Amagasaki, Japan

Hiroaki Tobuse