KR101049932B1 - Panel of cathode ray tube - Google Patents

Abstract

The present invention relates to a panel of a cathode ray tube designed to reduce the amount of doming due to thermal expansion of the shadow mask by designing the inner curvature of the panel to be suitable for the curvature of a shadow mask implemented in a super arc shape. In the panel of the cathode ray tube including a planar outer surface and the inner surface having a predetermined curvature, the shadow mask is located behind the shadow mask in which a plurality of electron beam passing holes are formed, the panel has a transmittance of 30 mm inward from the end of the effective screen ( TMbu) and the ratio of the transmittance (TMcorner) at the end of the effective screen satisfies the range of 80% to 90%, not only reduces the amount of dominance due to thermal expansion of the shadow mask, but also improves the uniformity of the brightness to improve product reliability and competitiveness There is an effect that can increase.

Panel, shadow mask, arc, super arc, cathode ray tube

Description

Panel for Cathode Ray Tubes {Panel for Cathode Ray Tube}             

1 is a side cross-sectional view showing the structure of a typical cathode ray tube.

2 is a view showing the structure of a typical cathode ray tube panel;

3 is a graph showing the radius of curvature of the panel according to the prior art,

4 is a distribution diagram showing the luminance distribution of the panel according to the prior art;

5 is a graph showing the radius of curvature of the panel according to the present invention;

6 is a distribution diagram showing the luminance distribution of the panel according to the present invention.

<Explanation of symbols on main parts of the drawings>

R: radius of curvature

The present invention relates to a panel of a cathode ray tube, and in particular, the inner curvature of the panel is designed to be suitable for the curvature of a shadow mask implemented in the form of a super arc to reduce the amount of dominance due to thermal expansion of the shadow mask. It relates to a panel of cathode ray tube.

1 is a side cross-sectional view showing the structure of a general color cathode ray tube.

A common color cathode ray tube is a front glass called a panel (1), and a rear glass called a funnel (2) are combined to form a vacuum outer container, the inside of which is a fluorescent surface (4) that serves as a predetermined light emission. An electron beam 6 for emitting a plurality of phosphors applied to the fluorescent surface 4, an electron gun from which the electron beam 6 is emitted, and a shadow for selecting colors such that the electron beam 6 emits a predetermined phosphor; It consists of a mask 3 and a frame 7 supporting it.

The color cathode ray tube is formed of the fluorescent surface formed on the inner surface of the panel 1 by the anode voltage applied to the cathode ray tube from the electron gun embedded in the neck portion of the funnel 2. 4), the electron beam 6 is deflected up, down, left, and right by the deflection yoke 5 before reaching the fluorescent surface 4 to realize an image.

Therefore, the shadow mask 3 needs to be designed with an accurate curvature in order to realize an image, and the curvature of the inner surface of the panel 1 is primarily considered as such curvature design condition.

2 is a diagram illustrating a typical cathode ray tube panel.

The panel 1 has a curved inner and outer surface, and a radius of curvature Rop of the outer surface of the panel and a radius of curvature Rip of the inner surface of the panel 1 are formed to satisfy a relationship of Rop > Rip to withstand the vacuum in the cathode ray tube. In addition, since the curvature radii Rop and Rip have an inverse relationship with each curvature, the curvature of the inner surface of the panel 1 is relatively larger than the outer curvature.

Since the geometrical characteristics of the panel 1 and the shadow mask 3 must coincide in order to substantially realize an image, the inner curvature of the panel 1 is considered as an important factor for determining the curvature of the shadow mask 3. The curvature of the shadow mask 3 determined here is closely related to the structural strength and heat deformation characteristics of the shadow mask 3.

3 is a graph showing the radius of curvature of the panel according to the prior art, Figure 4 is a distribution diagram showing the luminance distribution of the panel according to the prior art.

The panel according to the prior art is formed by the inner curvature and the outer curvature developed by a constant equation, so that when the outer curvature radius or the unfolding formula is constant and the inner curvature radius becomes small, the thickness increases at the end of the effective screen of the panel. There is a disadvantage in that the brightness uniformity (B / U) is reduced.

In addition, in forming the shadow mask, a portion of the sphere (sphere) is formed so that the curvature is larger toward the periphery than the arc (arc) applied to the curvature form of a super arc more effective for thermal expansion If it is to be formed as a problem that the design is inappropriate.

The present invention has been made to solve the above-mentioned problems of the prior art, the inner curvature of the panel is designed to be suitable for the curvature of the shadow mask implemented in the super arc shape, to reduce the amount of dominance due to thermal expansion of the shadow mask In addition, an object of the present invention is to provide a panel for a cathode ray tube which is formed to improve brightness uniformity.

The panel of the cathode ray tube according to the present invention for solving the above problems includes a substantially planar outer surface and an inner surface having a predetermined curvature, and on a panel of the cathode ray tube in which a shadow mask in which a plurality of electron beam passing holes are formed is located at the rear. The panel may satisfy a range of 80% to 90% of a transmittance (TMbu) at a point 30 mm inward from an effective screen end and a transmittance (TMcorner) of the effective screen end.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

5 is a graph showing the radius of curvature of the panel according to the invention, Figure 6 is a distribution diagram showing the luminance distribution of the panel according to the invention.

The panel of the cathode ray tube according to the present invention is a part corresponding to a screen on which image information is converted into final visual information, and includes a substantially flat outer surface and an inner surface having a predetermined curvature.                     

In this case, the panel has a transmittance (TMbu) of 30mm away from the end of the effective screen in which the image appears in the range of 80% to 90% compared to the transmittance (TMcorner) of the end of the effective screen, the following [ Equation 1].
80% ≤ TMbu / TMcorner≤ 90%

The geometry of the panel may be expressed based on three coordinate axes, namely, long axis (X axis), short axis (Y axis), and diagonal axis (D axis) on a two-dimensional plane with the center of the panel as an origin.
Here, the long axis (X axis) represents the left and right sides of the panel's horizontal axis, that is, the center of the panel, and the short axis (Y axis) is perpendicular to the long axis (X axis) of the panel's vertical axis, that is, the center of the panel. The lower and lower axes are shown, and the diagonal axis (D axis) represents the diagonal axis between the long axis (X axis) and the short axis (Y axis).

At this time, the curvature structure of the panel can be described as a whole by expressing on the basis of the long axis (X axis), short axis (Y axis) and the diagonal axis (D axis).

That is, if the distance from the center to the end of the effective screen is 1 based on the X axis, the panel has a thickness Tcx of the center in the X-axis direction and a thickness of a point 3/4 away from the center ( The ratio of Tx) preferably satisfies the range of 100% to 130%. That is, the thickness Tx at a point 3/4 away from the center may be 1 to 1.3 times the thickness Tcx of the center.

In addition, when the distance from the center to the end of the effective screen is 1 with respect to the Y axis, the panel is located at a thickness Tcy of the center in the Y-axis direction and a point 3/4 away from the center. It is preferable that the ratio of the thickness Ty satisfies the range of 100% to 120%. That is, the thickness Ty of a point 3/4 away from the center may be 1 to 1.3 times the thickness Tcy of the center.

When the distance from the center portion to the end of the effective screen is 1 based on the diagonal axis, the panel has a thickness Tcd of the center portion and a thickness of a point 3/4 away from the center portion. It is preferable that the ratio of Td) satisfies the range of 110% to 160%. That is, the thickness Td at a point 3/4 away from the center may be 1 to 1.6 times the thickness Tcd of the center.

Therefore, the panel of the cathode ray tube according to the present invention is configured as described above, in the panel according to the prior art, the luminance distribution at the panel periphery is more than the decrease in luminance uniformity that appears as the thickness of the panel periphery increases. Become uniform.

Therefore, the panel of the cathode ray tube according to the present invention configured as described above is curvature for the X-axis, Y-axis, diagonal axis toward the periphery of the panel compared to the radius of curvature (Rx1, Ry1, Rd1) of the panel according to the prior art Since the radius Rx2, Ry2, and Rd2 increases, the luminance distribution at the panel periphery becomes more uniform, and thus the luminance uniformity of the panel according to the prior art is reduced. It becomes possible.

As described above, the panel of the cathode ray tube according to the present invention has been described with reference to the illustrated drawings, but the present invention is not limited by the embodiments and drawings disclosed herein, and may be applied within the scope of the technical idea. .

The panel of the cathode ray tube according to the present invention configured as described above is formed with a certain relation such that the inner curvature is suitable for the curvature of the shadow mast implemented in the super arc shape, thereby reducing the amount of doming due to thermal expansion of the shadow mask. In addition, the brightness uniformity is improved to increase the reliability and competitiveness of the product.

Claims (4)

In the panel of the cathode ray tube including the outer surface and the inner surface having a predetermined curvature, the shadow mask in which a plurality of electron beam through-holes are formed is located in the rear, The panel is a cathode ray tube, characterized in that the transmittance (TMbu) at the point 30mm inward from the effective screen end and the transmittance (TMcorner) of the effective screen end satisfies the following relationship. 80% ≤ TMcorner / TMbu ≤ 90% The method of claim 1, When the panel has a distance from the center to the end of the effective screen on the basis of the X axis with the center as the origin, the thickness (Tcx) of the center in the X axis direction and the thickness of a point 3/4 away from the center A panel of a cathode ray tube, wherein (Tx) satisfies the following relationship. 100% ≤ Tx / Tcx ≤ 130% 3. The method of claim 2, When the panel has a distance from the center to the end of the effective screen as 1 based on the Y axis with the center as the origin, the thickness (Tcy) of the center in the Y axis direction and the thickness of a point 3/4 away from the center A panel of a cathode ray tube, wherein (Ty) satisfies the following relationship. 100% ≤ Ty / Tcy ≤ 120% The method of claim 3, When the panel has a distance from the center to the end of the effective screen on the basis of the diagonal axis having the center as the origin, the panel has a thickness Tcd of the center in the diagonal direction and a point 3/4 away from the center. A panel of a cathode ray tube, wherein the thickness Td satisfies the following relational expression. 110% ≤ Td / Tcd ≤ 160%

Images