JPH11120938A - Color cathode-ray tube panel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a problem that a local distortion is generated on a reflected image on an outer surface depending on the plane accuracy of the panel outer surface and the plane feeling of an image display section is remarkably impaired when the outer surface of the image display section of a color cathode-ray tube panel is formed into a complete plane. SOLUTION: The outer surface of the image display section of a color cathode-ray tube panel 11 is formed into an outward convex curved surface having the radius of curvature of about (W/2)<2> /2, where W is the major axis width of the image display section. A reflected image on the outer surface of the image display section is gently distorted as a whole, thus the local distortion of the reflected image is made inconspicuous to prevent the plane feeling of the image display section from being impaired.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a color cathode ray tube panel.

[0002]

2. Description of the Related Art FIG. 3 shows an image display unit having a flat outer surface,
FIG. 1 is a cross-sectional view showing a conventional color cathode ray tube having a panel whose inner surface is formed of a curved surface having a predetermined radius of curvature (a short-axis cross section above the center chain line, and a long-axis cross section below). In FIG. 3, reference numeral 1 denotes a panel having an outer surface of an image display unit formed of a flat surface and forming an envelope of a color cathode ray tube, and 2 denotes a panel 1.
A funnel constituting an envelope of a color cathode ray tube together with 3 is a phosphor screen in which red, blue and green phosphors are arranged in order on the inner surface of the panel, 4 is an electron gun, 5 is an electron gun 4
6 is a deflection yoke for electromagnetically deflecting the electron beam 5, and 7 is a shadow mask acting as a color selection electrode. FIG. 4 is a sectional view showing only the panel 1 of FIG.

Next, the operation will be described. Color cathode ray tubes
The inside is kept in a high vacuum by an envelope constituted by the panel 1 and the funnel 2, and the electron beam 5 emitted from the electron gun 4 is formed on the inner surface of the panel 1 and a high voltage is applied. The phosphor screen 3 emits light by colliding with the phosphor screen 3. At the same time, the electron beam 5 is applied to the deflection yoke 6
Are deflected up, down, left and right by the deflection magnetic field created by the above, and form an image scanning area called a raster on the fluorescent screen 3. In this image scanning area, the distribution of the emission intensities of the red, blue, and green colors of the phosphor screen 3 according to the amount of projection of the electron beam 5 is observed from the outer surface of the panel 1 and recognized as a color image. Numerous holes are arranged in order in the shadow mask 7, and the electron beam 5 passes through the holes to geometrically illuminate predetermined positions of the red, blue, and green phosphors on the phosphor screen 3. And make accurate color selection. For this reason, the electron gun 4, the shadow mask 7, and the inner surface of the image display section of the color cathode ray tube panel 1 need to maintain a predetermined positional relationship accurately.

On the other hand, regarding the outer surface of the image display section of the color cathode ray tube panel 1, there is no structural restriction related to the electron gun 4 and the shadow mask 7 unlike the inner surface of the image display section. The outer surface of the color cathode ray tube to be constituted is generally configured to be a perfect plane (infinite radius of curvature) as shown in FIG.

[0005]

The outer surface of the image display portion of the conventional color cathode ray tube panel in which the outer surface of the image display portion is flat is configured to be a perfect plane (infinite radius of curvature) as described above. However, it has been extremely difficult in the manufacturing process of the panel to form a precise and complete flat surface over the entire outer surface of the image display section of the color cathode ray tube panel. In addition, depending on the planar accuracy, an externally reflected image on the outer surface of the image display unit of the color cathode ray tube panel 1 locally distorts, so that the flatness of the image display unit is significantly impaired. Was.

Further, when the outer surface of the image display section of the color cathode ray tube panel is formed of a flat surface, the contact between the outer surface of the image display section and the contact portion of the cabinet is a flat-to-flat contact. In some cases, a gap is easily formed between the outer surface of the image display section of the color cathode ray tube panel and the contact surface with the cabinet, and there has been a problem that the value as a product is significantly impaired.

[0007]

SUMMARY OF THE INVENTION A color cathode ray tube panel according to the present invention has been made in order to solve the above-mentioned problems, and the long axis width of an image display portion of the color cathode ray tube panel is W. time, in which the external surface of the image display section radius of curvature is constituted by approximately (W / ²⁾ 2/2 to become such a outwardly convex curved surface.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiment 1 FIG. FIG. 1 is a cross-sectional view showing a color cathode ray tube panel according to Embodiment 1 of the present invention (a short axis section is shown on the right side of the chain line, and a long axis section is shown on the left side). FIG. 2 is a cross section showing a color cathode ray tube employing this panel. It is a figure (short axis cross section above a chain line, long axis cross section below). In FIG. 2, reference numeral 11 denotes a color cathode ray tube panel in which the outer surface of the image display unit is a curved surface having a predetermined radius of curvature and is convex outward, and the inner surface is formed of a curved surface with a predetermined radius of curvature. A funnel constituting an envelope of a color cathode ray tube together with 3 is a phosphor screen formed by arranging red, blue and green phosphors in order on the panel inner surface, 4 is an electron gun, and 5 is emitted from the electron gun 4. A deflection yoke 6 for deflecting the electron beam 5 electromagnetically;
Reference numeral 7 denotes a shadow mask that functions as a color selection electrode.

Next, the operation will be described. Color cathode ray tubes
The inside is kept in a high vacuum by an envelope constituted by the panel 11 and the funnel 2, and the electron beam 5 emitted from the electron gun 4 is formed on the inner surface of the panel 11, and a high voltage is applied. The phosphor screen 3 emits light by colliding with the phosphor screen 3. At the same time, the electron beam 5 is deflected up, down, left, and right by a deflection magnetic field generated by a deflection yoke 6, and forms an image scanning area called a raster on the phosphor screen 3. In this image scanning area, the distribution of the emission intensity of each of the red, blue, and green colors of the phosphor screen 3 according to the amount of impact of the electron beam 5 is observed from the outer surface of the panel 11 to be recognized as a color image. Numerous holes are arranged in order in the shadow mask 7, and the electron beam 5 passes through the holes to geometrically illuminate predetermined positions of the red, blue, and green phosphors on the phosphor screen 3. And make accurate color selection. For this reason, the electron gun 4, the shadow mask 7, and the inner surface of the image display section of the color cathode ray tube panel 11 need to maintain a predetermined positional relationship accurately.

On the other hand, the outer surface of the image display section of the color cathode ray tube panel 11 has no structural restrictions due to the electron gun 4 and the shadow mask 7, and the like. It can be arbitrarily determined from conditions in the manufacturing process and the like.

The image display area of a 15-inch to 21-inch color cathode-ray tube, which is the size of a general display monitor color cathode-ray tube, and the viewing distance of about 500 mm, which is a normal use condition of a display monitor, are different. Then, the maximum value of the surface drop of the image display unit outer surface (the difference between the highest point and the lowest point of the image display unit outer surface height) of the color cathode ray tube panel, which can be visually regarded as a flat surface, is about 1 mm. Now, when the image display manager axis width of the color cathode ray tube panel 11 is W, the outer surface radius of curvature R which fall is about 1mm in the image display section end is obtained as ^{(W / 2) 2/2} .

Accordingly, the outer surface of the color cathode ray tube panel 11 the long axis width of the image display unit is W as shown in FIG. 1, at approximately the radius of curvature is convex outward (W / ²⁾ 2/2 of the curved surface With this configuration, the reflection image on the outer surface can be gently distorted as a whole without visually impairing the flatness, so that local distortion can be made inconspicuous, and the flatness of the image display unit can be prevented. be able to.

[0013]

As described above, according to the present invention, the outer surface of the image display portion of the color cathode ray tube panel having the image display surface as a flat surface is formed with a curved surface which is outwardly convex so as not to visually impair the flatness. Therefore, local distortion of the reflection image on the outer surface of the display unit can be made inconspicuous, and the flatness of the image display unit is not impaired.

Further, the contact between the outer surface of the display portion of the color cathode ray tube and the cabinet becomes a curved surface and a flat surface, and the entire contact portion can be pressed and contacted, so that no gap is generated and the value as a product is impaired. There is no.

In addition, in view of the panel manufacturing process by press molding and surface polishing, the outer surface of the image display portion of the color cathode ray tube panel is constituted by a curved surface, so that the color cathode ray tube panel can be separated from the mold at the time of press molding and can be removed at the time of polishing. The uniformity of the surface pressure can be improved, and the manufacturability can be greatly improved as compared with the case where the outer surface of the image display section is formed of a flat surface.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a color cathode ray tube panel according to Embodiment 1 of the present invention (a short-axis cross section is on the right side of a chain line, and a long-axis cross section is on the left side of a chain line).

FIG. 2 is a cross-sectional view showing a color cathode ray tube employing the color cathode ray tube panel of the first embodiment (a short axis cross section above a chain line and a long axis cross section below the chain line).

FIG. 3 is a cross-sectional view showing a conventional color cathode ray tube (a short-axis cross section above the chain line and a long-axis cross section below the chain line).

FIG. 4 is a cross-sectional view showing a conventional color cathode ray tube panel (a short-axis cross section is on the right side of the chain line and a long-axis cross section is on the left side of the chain line).

[Explanation of symbols]

2 funnel, 3 phosphor screen, 4 electron gun, 5 electron beam, 6 deflection yoke, 7 shadow mask, 11 color cathode ray tube panel.

Claims (1)

[Claims] When a 1. A long axis width of the image display unit of the color cathode ray tube panel is W, the outer surface of the image display section a radius of curvature substantially (W / ²⁾ 2/2 to become such outside convex A color cathode ray tube panel characterized by having a curved surface.