In-line electron gun structure for color cathode ray tube having oblong apertures
AssigneeNorth American Philips Consumer Electronics Corp.
InventorDonald L. Say
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Abstract
The effective aperture sizes of the final focusing and accelerating electrodes of an in-line electron gun structure for color cathode ray tubes are increased by elongating the apertures, expanding the outer edges of the side apertures, and surrounding the apertures with a peripheral raised rim which balances the asymmetry introduced into the apertures by enlargement. Partitions between the aperture may be radiused so their center height is lower than the height at the edges. The raised rim of the final accelerating electrode is generally higher than the raised rim of the focusing electrode.
Claims9
In an in-line electron gun structure for a color cathode ray tube, a lensing arrangement in the final focusing and accelerating electrodes comprising:
- a first lensing structure in the forward portion of the focusing electrode, such structure having an upstanding perimetrical rim defining an oval-shaped cavity, and two upstanding partition walls extending across the width of the cavity, at least a central portion of the walls having a height substantially less than the height of the rim, the rim and walls together defining three vertically elongated in-line apertures, the central aperture being oblong and the side apertures being D-shaped, and
- a second lensing structure in the rear portion of the final accelerating electrode in adjacent, facing relationship with the first structure, such second structure having an upstanding perimetrical rim defining an oval-shaped cavity, and two upstanding partition walls extending across the width of the cavity, at least a central portion of the walls having a height substantially less than the height of the rim, the rim and walls together defining three vertically elongated in-line apertures, the central aperture being oblong and the side apertures being D-shaped.
Dependencies are inferred from the claim text.