KR0177121B1 - Cathode ray tube - Google Patents

Abstract

The present invention discloses a novel panel configuration.

Conventional panels have a problem in that the peripheral image is distorted, the flatness is low, the strength is weak, and the panel thickness is large, so that the design and manufacture are difficult.

In the present invention, the radius of curvature of the diagonal axis includes the radius of curvature of the major axis or the minor axis to provide a panel having excellent image quality and strength, and easy to design and manufacture.

Description

Panel of CRT

1 is a cross-sectional view showing an example of the configuration of a conventional panel.

2 is a graph showing the distribution of panel thickness in a conventional panel.

3 is a cross-sectional view showing the configuration of a panel according to the present invention.

4 is a graph showing the thickness distribution of the panel of the present invention.

* Explanation of symbols for main parts of the drawings

H: Long axis V: Short axis

D: diagonal axis

Rh, Rv, Rd, Rd ': radius of curvature

Th, Tv, Td: Panel Thickness

t: (predetermined distance that curvature radius or panel thickness changes)

The present invention relates to a CRT, and more particularly to a panel thereof.

If the fluorescent screen is formed on the inner surface of the CRT panel, the panel does not satisfy the requirements for image quality such as image display near flatness and reflection of external light without distortion, and the requirements for intensity such as external shock and vacuum stress. Can not be done.

Since the emission center of the electron beam emitting the fluorescent surface of the panel is positioned around one point for each gun, it is preferable that the panel is spherical for proper landing of the electron beam. However, when the panel is spherical, it not only protrudes excessively from the cabinet, but also narrows the viewing angle, distorts the surrounding image, and impairs the flatness of the image. Thus, the panel is aspherical.

Aspheric panels are usually designed and manufactured by displaying their curved surfaces in polynomial evolution and determining their coefficients mathematically or experimentally.

Accordingly, a general panel has a schematic shape as shown in FIG. 1. The curvature radii of the long axis (H), the short axis (V), and the diagonal axis (D) of the panel are referred to as Rh, Rv, and Rd, respectively. In general, RdRhRv has a relationship.

On the other hand, the thickness of the panel is the difference between the radius of curvature of the outer surface minus the radius of curvature of the inner surface. When the panel thickness in each axial direction is Tv, Th, and Td, the general panel is shown in FIG. 2 according to the relationship of FIG. Likewise, TvThTd has a relationship.

As such, the panel has a compound curvature having a different radius of curvature in each axis direction, so the design and manufacture of the panel is relatively difficult. In particular, in the case of a color CRT, it is difficult to design and manufacture a shadow mask corresponding to this panel, as well as a problem of deterioration of color purity at corners. In other words, the curvature in each axial direction should meet at the corner of the panel and finish with an appropriate compound curvature. In the conventional panel, the curvature of the axial curvature is difficult, so that the landing of the proper electron beam is not performed at the corner, thereby degrading the color purity.

A further problem in the conventional panel is that the entire screen is not flat and the panel is a curved surface having a large difference from the spherical surface, so that the distortion of the surrounding image is large and the flatness is low.

In addition, since the panel thickness is partially different, it is difficult to design and manufacture, and the thickness of the panel at the outer edge of the corner portion, ie, the diagonal axis D, which is most frequently impacted by external shock, is low.

In view of the various problems of the related art, an object of the present invention is to provide a panel that is easy to design and manufacture, and which is excellent in image quality and strength.

In order to achieve the above object, the panel according to the present invention is characterized in that the radius of curvature of the diagonal axis includes the radius of curvature of the major axis or the minor axis.

The meaning of inclusion here means that the radius of curvature in the diagonal axis has the same radius of curvature as the radius of curvature of the major or minor axis from the center of the panel to the predetermined distance, and the radius of curvature that is different from the above predetermined distance to the outside. It means to have a radius.

Such specific features and advantages of the present invention will become more apparent from the following description of the preferred embodiments with reference to the accompanying drawings.

In Fig. 3, the radius of curvature Rd in the diagonal axis D direction is the same as the radius of curvature Rh in the long axis H direction from the panel center 0 to the predetermined distance t. The outer end side from (t) has a different radius of curvature Rd '. Preferably, the outer radius of curvature Rd 'is larger than the inner radius of curvature Rd, that is, the radius of curvature Rh in the major axis H direction. That is, Rd≥Rh.

At this time, if the curvature radius of the inner surface of the panel is maintained as it is, the panel thickness Td inside the diagonal axis D becomes the same as the panel thickness Th in the long axis H direction as shown in FIG. 4 and outside the predetermined distance t. The panel thickness Td in the diagonal axis D direction is larger than the panel thickness Tn in the long axis H direction. That is, Td≥Th.

According to such a configuration, the panel becomes flat as a whole, in particular toward the outside, thereby preventing distortion of peripheral images and providing flatness.

In addition, the overall thickness of the panel is uniform, so that the design and fabrication is easy, and in particular, the panel thickness of the diagonal outer edge, that is, the corner portion is increased, so that the panel can effectively resist external forces such as impact.

In the above description, the present invention has been described only with respect to the curvature radii Rd and Rd ', Rh and the panel thicknesses Td and Th between the diagonal axis D and the long axis H, but the present invention has a correlation with the short axis V. It can also be established for. For example, the curvature radii (Rd, Rh, Rv) or panel thicknesses (Td, Th, Tv) in the directions of the respective axes (D, H, V) are equal to one predetermined distance or to another predetermined distance between the respective axes, and outwardly. It can be configured to make a difference. This configuration makes it possible to achieve evenness of the screen flatness and panel thickness with even greater effects.

That is, Rv≥Rd or Rv≥Rd. As such, the present invention has an effect of providing a panel having excellent image quality and strength at a low production cost.

Claims (7)

The curvature radius of the panel in the major axis (H), minor axis (V), diagonal axis (D) direction Rh, Rv, Rd and the panel thickness of Th, Tv, Td, the curvature of the diagonal axis (D) direction A panel of CRT, characterized in that the radius (Rd) comprises a radius of curvature (Rh, Rv) in the long axis (H) or short axis (V) direction. The radius of curvature of the diagonal axis (D) is equal to the radius of curvature (Rh or Rv) of the major axis (H) or minor axis (V) from the center of the panel to a predetermined distance (t). And a curvature radius (Rd ') different from the outside thereof. The panel thickness of claim 1, wherein the panel thickness in the diagonal axis direction D is equal to the panel thickness Th or Tv of the major axis H or the minor axis V, from the center of the panel to a predetermined distance t. Panel of CRT characterized by having different panel thickness from the outside. The panel of a CRT according to any one of claims 1 to 3, wherein a relationship of Rd? Rh or Rv? Rd is established. The panel of the CRT according to claim 1 or 3, wherein a relationship of Rd? Rh or Tv? Td is established. The CRT panel according to claim 2, wherein the radius of curvature Rd 'outside of the diagonal axis D is larger than the radius of curvature Rh of the long axis H. 4. The CRT panel according to claim 3, wherein the outer panel thickness Td in the diagonal axis D direction is larger than the panel thickness Th in the long axis H direction.