Matsushita Electronics Corporation

Michio Ohsugi

Hironari Taniguchi

Kanji Imai

Kiyoshi Hamada

Takatsugu Kurata

Koji Matsuo

An image display apparatus comprises, in a vacuum container whose inside is kept under vacuum, a fluorescent layer, an electron emission source having a plurality of electron sources, a deflecting electrode to deflect electron beams emitted from the electron emission source, and an ultrafocusing electrode to focus the electron beams and land the focused electron beams on predetermined positions of the fluorescent layer. The ultrafocusing electrode is arranged between the electron emission source and the fluorescent layer while the deflecting electrode is arranged between the electron emission source and the ultrafocusing electrode, so that the fluorescent layer is illuminated by the electron beams. If the landing position of the electron beam is deviated because of errors such as manufacturing errors in assembling the components into the image display apparatus, the deviation is minimized and an image display apparatus with high resolution can be obtained.

Image display apparatus

An image display device has a plurality of electrodes that control a beam between a group of linear cathodes (,) and a screen (,) with a phosphor layer, and is provided with a circuit (,) for generating a beam track offset signal, which generates a signal for slightly oscillating one of the beams horizontally, a PIN photodiode (,) for detecting the emission amount of the phosphor layer for this beam, a comparator (,) for generating a beam irradiation position misalignment signal based on the detected emission amount, an integrating circuit (,) for generating a beam position control signal in correspondence with the beam irradiation position misalignment signal; and a horizontal deflection electrode driving circuit (,) for driving a horizontal deflection electrode (,) in accordance with the beam position control signal. With this configuration, misalignments of the position of the beam spot and the phosphor stripes on the screen, which are caused for various reasons, can be suppressed, and an image display device is obtained, in which a deterioration of the image quality, such as color misalignments, does not occur.

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Osaka, Japan

Michio Ohsugi