Matsushita Electronics Corporation

Hiroto Nakamura

Kakuichiro Hosokoshi

Akira Sato

Takami Okamoto

Masakazu Maeda

A color television tube assembly in which the aperture of a control grid of each electron gun is made in the form of an ellipse with its major axis in line with the vertical direction, and the lengths of the vertical and horizontal axes of the aperture of action space of an electron lens electrode are selected different from each other, whereby the beam spot at the center of the screen may become in the form of a vertically elongated ellipse while the beam spots at the horizontal and vertical edges of the screen are in the form of a horizontally elongated ellipse.

In line electron guns for color tubes, each having a control grid with

In a process for exposing a photosensitive layer formed upon the inside of the faceplate of a color-picture tube so as to form a desired pattern of phosphor dots or temporary dots or the like, an optical correction system for causing the light beam to precisely impinge at a point where the electron beam impinges is interposed between a light source and a shadow mask. The system comprises an optical lens system for correcting .DELTA.S deviation characteristics and an optical lens system for correcting .DELTA.P deviation characteristics consisting of a first optical correction system and a second optical system. The first optical system is so designed as to attain the average correction depending only upon the deflection angle regardless of each of the radial directions of deflection while the second optical system is so designed as to attain the individual .DELTA.P deviation characteristics depending not only upon the deflection angle but also upon each of the radial directions of deflection. The correction lenses may have a relatively simple aspherical surface.

Method for manufacturing the phosphor screen of color-picture tube

A color picture tube, wherein a set of three electron beams emitted from respective three electron-emitting members of an in-line type electron gun, or from respective three electron guns, is projected through slot-shaped apertures of a shadow mask onto a screen, and sets of each three luminous strips are formed separated from each other and surrounded by light absorbing black film, and the three electron beams selectively energize the luminous strips to emit luminous color images, the length and width of the slots on the shadow mask and those of the phosphor strips having specified correlations in the central part of the picture screen and the shadow mask, and different correlations in the corner parts of the screen and the shadow mask so that color picture reproduction in contrast, brightness and color balance is satisfactory over the entire screen.

Growing community of inventors

Takatsuki, Japan

Hiroto Nakamura