KR20050025036A - Color Cathode-Ray Tube - Google Patents

Abstract

PURPOSE: A color cathode ray tube is provided to reduce vacuum stress in the cathode ray tube and improve resistance against impact by optimizing the configuration of the panel and the funnel of the cathode ray tube. CONSTITUTION: A color cathode ray tube comprises a panel having an inner surface on which a phosphor screen is formed; a funnel sealed to the panel; an electron gun mounted in a neck portion of the funnel so as to emit electron beams to the phosphor screen; a deflection yoke mounted in a yoke portion of the funnel so as to deflect electron beams; a shadow mask spaced apart from the phosphor screen; and a frame for supporting and fixing the shadow mask. The value obtained from the expression CFT/SET is 1.04 or lower, wherein CFT is the thickness of the panel at a deflection center axis defined by the axis extended from the center axis of the electron gun to the front surface of the panel, and SET is the thickness of the skirt of the panel.

Description

Color Cathode Tube {Color Cathode-Ray Tube}

The present invention relates to a color cathode ray tube, and more particularly, to a color cathode ray tube in which stress caused by internal vacuum pressure of the cathode ray tube is reduced by optimizing the structure of the panel and the funnel.

1 shows a schematic view of a typical colored cathode ray tube. As shown, a fluorescent screen 4 of R, G, and B is applied to the inner surface, and a panel 1 having an explosion-proof means fixed to the front surface thereof, a funnel 2 fused to the rear end of the panel; , An electron gun inserted into the neck portion 13 of the funnel to radiate the electron beam 6, a deflection yoke 5 for deflecting the electron beam 6, and an electron beam 6 mounted at regular intervals inside the panel. A shadow mask 3 having a plurality of holes formed therethrough, a main frame 7 and a subframe 8 fixedly supporting the shadow mask 3 at regular intervals from an inner surface of the panel, and connecting the frame and the panel. Consists of a corner spring (9) to support, an inner shield (10) shielding the cathode ray tube to be less influenced by external geomagnetism, and a reinforcement band (12) installed around the side of the panel to prevent external impact. And a magnet (11) for modifying the trajectory so that the electron beam hits a predetermined phosphor accurately is attached to the rear surface of the deflection yoke.

The manufacturing process of the color cathode ray tube having such a structure is largely divided into a pre-process and a post-process. The former process is a process of applying a fluorescent surface to the inner surface of the panel, and the post process is made up of the following several processes. First, a panel in which a fluorescent surface is applied and a mask assembly embedded therein and a funnel coated with frit on the seal surface are bonded to each other in a high temperature furnace process, and then an electron gun is applied to the inner surface of the neck portion of the funnel in an encapsulation process. After insertion, the inside of the cathode ray tube is made into a vacuum state through an exhaust process and then sealed. When the cathode ray tube is in a vacuum state, the panel and the funnel are subjected to high tensile and compressive stresses. Therefore, the cathode ray tube is completed by a reinforcing process in which a reinforcing band is attached to disperse high stress applied to the front surface of the panel after the exhaust process.

Figure 2 schematically shows the distribution of stress applied to the panel and the funnel glass after the vacuum evacuation process of the cathode ray tube manufacturing process, the dotted line shows the compressive stress, the solid line shows the tensile stress. In general, when the glass is impacted from the outside, cracks are generated. In this case, the tensile stress applied to the glass surface not only accelerates the progress of the crack, but also may cause the glass to be stiffened if the glass is severely strong. In contrast, the compressive stress serves to prevent the crack from further developing. That is, as shown in FIG. 2, the center portion of the panel after the cathode ray tube exhaust process is relatively stress resistant due to the compressive stress, but the tensile stress is generated at the corner portion and the seal line portion of the panel, so that even a slight impact is easily broken.

Moreover, in recent years, as the cathode ray tube is digitized and slimmed, stress is severely generated by the internal vacuum of the cathode ray tube. That is, as the cathode ray tube is slimmer, the internal vacuum degree is maintained in the same state, and the volume of the cathode ray tube is reduced, so that stress caused by vacuum in the glass is greatly generated. In addition, in order to reduce the power consumption of the deflection yoke, the cathode ray tube made of the yoke portion of the funnel in a rectangular shape has a problem in that the funnel shape is structurally weak and high tensile stress is formed on the glass, thereby easily breaking in the thermal process.

On the other hand, heat treatment during fabrication to stably lower the high tensile stress of the funnel glass may form a compressive stress to increase the impact resistance on the glass surface. However, such a process not only increases the price but also has a disadvantage in that the manufacturing process is difficult.

An object of the present invention is to provide a color cathode ray tube that can effectively reduce the stress and secure impact resistance by optimizing the structure of the panel and the funnel of the cathode ray tube.

The color cathode ray tube of the present invention includes a panel having a phosphor screen on an inner surface thereof, a funnel sealed in a vacuum state on the panel, an electron gun mounted to a neck portion of the funnel to emit an electron beam toward the phosphor screen, and the funnel And a deflection yoke mounted to the yoke of the deflection yoke, a shadow mask disposed at a predetermined interval with respect to the phosphor screen on the inner surface of the panel to serve as color screening, and a frame for fixing and supporting the shadow mask. When the thickness of the panel in the deflection central axis defined as the axis extending from the center of the electron gun to the front of the panel is called CFT, the thickness of the skirt of the panel is called SET, and the overall height in the direction of the center axis of the panel is OAH. , CFT / SET is characterized in that it satisfies 1.04 or less.

According to a feature of the invention, the tensile stress (hereinafter referred to as 'vacuum stress') of the panel of the present invention is referred to as the thickness at the deflection central axis of the panel is called CFT, the thickness of the skirt of the panel is called SET, When the overall height of the central axis in the direction is OAH, it is greatly reduced compared to the conventional panel vacuum stress in the following equation CFT / SET ≤ 1.04. That is, the high vacuum stress of the cathode ray tube is very sensitive to cracks and breakage due to external impact, so in the case of the panel, the thickness CFT in the deflection central axis of the panel, the thickness SET of the skirt of the panel, and the overall height in the central axis direction of the panel By optimizing the structure of OAH, stress can be effectively reduced and impact resistance can be obtained.

Hereinafter, with reference to the accompanying drawings, a specific embodiment according to the present invention will be described.

<Example>

3 is a cross-sectional view for explaining the structure of the cathode ray tube panel of the present invention.

As shown in Fig. 3, when the thickness at the deflection center axis of the panel of the present invention is a, the thickness at the corners is b, and the b / a value is the wedge ratio, the wedge ratio is 1.5 or more, and the vacuum is increased. The stress can be reduced and the impact resistance can be improved at the same time.

As shown in FIG. 3, in the cathode ray tube panel of the present invention, the thickness at the deflection central axis is called CFT, the thickness of the panel skirt is called SET, and the overall height in the central axis direction of the panel is called OAH.

Table 1 shows the vacuum stress of the cathode ray tube panel while changing the CFT, OAH, and SET as compared with the panel vacuum stress of the conventional cathode ray tube.

location Species Invention One One 2 3 4 5 CFT 12.5 10.5 10.5 10.5 10.5 12.5 OAH 110 90 90 90 100 110 SET 11.4 13 14 16 11.4 12 CFT / SET 1.10 0.81 0.75 0.66 0.92 1.04 OAH / SET 9.65 6.92 6.43 5.63 8.77 9.17 Vacuum stress (panel) 30.5 MPa 16.8 MPa 14.0 MPa 13.6 MPa 14.6 MPa 15.7 MPa

As shown in Table 1, it can be seen that the vacuum stress is significantly lower than the conventional case when the CFT / SET value satisfies the formula CFT / SET ≤ 1.04. Therefore, when the value of CFT / SET is set to 1.04 or less, a cathode ray tube with improved vacuum stress can be obtained than in the conventional case.

In addition, as a modified embodiment of the present invention, in contrast to limiting the range of CFT / SET values as described above, when the formula OAH / SET ≤ 9.2 is further satisfied, the vacuum stress of the cathode ray tube panel of the present invention is a conventional cathode ray. It can be significantly reduced compared to the vacuum stress of the tube panel. 4 is a schematic diagram analyzing the vacuum stress and deflection angle of the cathode ray tube according to the present invention. As can be seen from Figures 4a and 4b, when optimizing the structure of the CFT, SET, OAH, the vacuum stress is effectively reduced correspondingly.

Figure 5 is a cross-sectional view showing a funnel yoke portion used in the color cathode ray tube according to an embodiment of the present invention.

As shown in FIG. 5, the shape of the yoke portion of the funnel has a rectangular shape whose vertical cross section is not round. Using a rectangular yoke can reduce the power consumption of the deflection yoke during cathode ray tube operation.

In addition, all the above embodiments can be applied to a color cathode ray tube in which the outer surface of the panel is substantially flat as it is, and the same effect can be obtained in a so-called flat color cathode ray tube in which such treatment is performed.

As described above, the present invention optimizes the structure of the panel and the funnel of the wide angle and slim type cathode ray tube to reduce the vacuum stress inside the cathode ray tube and at the same time ensure the impact resistance of the cathode ray tube so that it is not easily damaged by external impact. There is.

1 is a schematic view of a typical colored cathode ray tube.

FIG. 2 is a diagram schematically illustrating a distribution of stress applied to a panel and a funnel glass after a vacuum evacuation process during fabrication of a cathode ray tube. FIG.

3 is a cross-sectional view for explaining the structure of a cathode ray tube panel of the present invention.

Figure 4 is a schematic diagram analyzing the vacuum stress and deflection angle of the cathode ray tube according to the present invention.

Figure 5 is a cross-sectional view showing a funnel yoke portion used in the color cathode ray tube according to an embodiment of the present invention.

***** Explanation of symbols for the main parts of the drawing *****

1: panel 2: funnel

3: shadow mask 4: fluorescent surface

5: deflection yoke 6: electron beam

7: main frame 8: sub-frame

9: spring 10: inner shield

11: magnet 12: reinforcement band

13: neck

Claims (5)

A panel having a phosphor screen on an inner surface, a funnel sealed in a vacuum state to the panel, an electron gun mounted on a neck portion of the funnel to emit an electron beam toward the phosphor screen, and an electron beam mounted on a yoke portion of the funnel In the color cathode ray tube comprising a deflection yoke for deflecting, a shadow mask disposed at a predetermined interval with respect to the phosphor screen on the inner surface of the panel to serve as color screening, and a frame for fixing and supporting the shadow mask. The thickness of the panel in the deflection central axis defined as the axis in which the central axis of the electron gun extends to the front surface of the panel is referred to as CFT, The thickness of the skirt of the panel is called SET, A color cathode ray tube, characterized in that CFT / SET satisfies 1.04 or less. The method of claim 1, In the cross section of the panel, the thickness at the deflection center axis is a, the thickness at the corners is b, and the b / a value is called a wedge ratio. Color cathode ray tube, characterized in that the wedge ratio is 1.5 or more. The method of claim 1, When the overall height in the central axis direction of the panel is called OAH, The color cathode ray tube which satisfy | fills OAH / SET 1.04 or less. The method of claim 1, The funnel is a color cathode ray tube, characterized in that the vertical cross section of the yoke portion is rectangular. The method of claim 1, Color cathode ray tube, characterized in that the outer surface of the panel is substantially flat.