KR20010095591A - Electronic Gun of Cathode-Ray Tube - Google Patents

Abstract

PURPOSE: A CRT electron gun is provided to lengthen useful life of the electron gun and improve voltage withstanding characteristics by preventing collision of electrons. CONSTITUTION: A CRT electron gun(40) comprises a cathode(41) having a heater and which emits electrons; a plurality of grid electrodes(42-1 to 42-6) for controlling the volume of the electron emission, and accelerating and focusing operation for the emitted electrons; a plurality of insulating support members(bead glass)(45) installed at upper and lower ends of the grid electrode, and which maintains constant spacing between grid electrodes; and a connector(49) for applying the voltage applied from an external stem pin to the relevant electrode. The insulating support member has a protruded portion(46), and the connector is installed at the surface of the protruded portion. Thus, the connector is prevented from touching electrodes.

Description

Electronic Gun of Cathode Ray Tube {Electronic Gun of Cathode-Ray Tube}

BACKGROUND OF THE INVENTION Field of the Invention The present invention relates to an electron gun for a cathode ray tube, and in particular, to extend a portion of a rectangular bead glass (hereinafter referred to as an "insulation support body") supporting each electrode of the electron gun, and to apply a voltage application connector on an extended part surface. The present invention relates to an insulating support for an electron gun which can prevent a discharge and a touch phenomenon between a connector and each electrode.

1 is a side view showing a cross section of a general color cathode ray tube, in which red, green, and blue phosphors are coated on an inner surface of a panel 10 to form a fluorescent surface, and an electron gun in a neck portion 50 behind the panel 10. The funnel 30 in which 40 is sealed is fused by glass to maintain a high vacuum of about 10 ⁻⁷ Torr.

The shadow mask 60, which serves as color screening of the electron beam scanned by the electron gun 40, is fixed to the support frame 70 at a portion proximate to the fluorescent surface 20 of the inner surface of the panel.

In addition, a deflection yoke 80 is provided at the interface between the funnel 30 and the neck 50 to deflect the electron beam scanned by the electron gun 40 to the entire fluorescent surface, and an electron beam is provided on the outer surface of the neck 50. Magnets 90 of 2, 4 and 6 poles are provided to correct the trajectory of the trajectory so as to strike the predetermined phosphor.

The electron gun 40 that emits the electron beam in the cathode ray tube configured as described above is provided with a cathode 41 that emits the electron beam as the voltage is applied as shown in FIG. The first electrode 42-1 for controlling, the second electrode 42-2 which is installed in proximity to the first electrode and accelerates the emitted electron beam, and the shear focusing lens which is installed in proximity to the second electrode Third and fourth electrodes 42-3 and 42-4 to be formed, and fifth and sixth electrodes 42-5 'and 42-5, which are provided to be close to the fourth electrode to form a capacitive focusing lens. 42-6 and a shield cup 43 fixed to the sixth electrode 42-6 to shield an external electric field and a magnetic field, which are mutually spaced apart by an insulating support 45. Keeping up.

Each electrode is supplied with a different voltage through a connector 49 connected via a stem pin 48 fixed to the stem 47. The stem 47 is sealed to the neck portion 50.

Accordingly, when the electron gun is supplied with power from the stem pin 48 to the heater in the cathode 41 constituting the triode, and the heater generates heat, hot electrons are emitted from the electron emission material applied to the tip of the cathode 41.

The emitted electrons are accelerated and focused while passing through the plurality of grid electrodes 42-1 to 42-6, pass through a shadow mask 60 that performs color screening, and then collide with the fluorescent surface 20 to emit phosphors. The screen is reproduced.

In this case, in order to reproduce the image, the electron beam must be sequentially scanned over the entire area of the screen. For this purpose, a self-focusing deflection yoke 80 using a non-uniform magnetic field is applied.

3 illustrates the lens characteristics of a general deflection yoke, and the distribution of the magnetic field generated by the deflection yoke 80 using the self-focusing type can be explained by dividing into two and four pole components. Acts to deflect the electron beam in the horizontal and vertical directions, and the four-pole component, i.e., the lens of the deflection yoke 80, focuses the electron beam in the vertical direction and diverges in the horizontal direction. The beam is focused at a shorter distance, causing a halo phenomenon in which the vertical direction rises convexly on the screen, resulting in deterioration of image quality.

FIG. 4 illustrates the lens characteristics of the electron gun and the deflection yoke in order to compensate the lens characteristics of the deflection yoke 80 of FIG. 3. In order to solve the problem shown in FIG. It is possible to cause the electron beams in the horizontal and vertical directions to be simultaneously focused at one point by offsetting the quadrupole component generated by the self-focused deflection yoke 80 generated at 40).

That is, in order to form a quadrupole lens, as shown in FIG. 2, the fifth electrode 42-5 of the electron gun is divided into two parts by the first focusing electrode 42-5 ′ and the second focusing electrode 42-5 ″. The above problem is solved by applying a low voltage to the first focusing electrode 42-5 'and a high voltage to the second focusing electrode 42-5 ", thereby generating a potential difference between the dynamic four-pole electrodes to form a four-pole lens. It becomes possible.

However, due to the difference in the electron beam travel distance between the center of the screen and the periphery, the electron beam is still focused in front of the screen, causing a hollow phenomenon.

Therefore, in order to solve this problem, when the electron beam is deflected to the periphery of the screen, a dynamic voltage (variable voltage) of a parabola waveform synchronized with the deflection frequency is applied to the second focusing electrode 42-5 " By adjusting the focal length of the beam by reducing the intensity, a method of solving the above problems is mainly employed.

FIG. 5 shows a grid electrode and an insulator support portion of an electron gun according to the prior art, and FIG. 5A is a plan view and FIG. 5B is a side view.

Here, when the dynamic voltage of the parabolic waveform, which is the variable voltage, is applied to the second focusing electrode 42-5 ″ of the fifth electrode 42-5 through the connector 49, the connector 49 supports the electron gun. To pass through the outside of each grid electrode (42-1 to 42-5 ') inserted into the insulating support 45.

At this time, the flexible connector 49 is deformed due to the high temperature heat during the manufacturing process of the cathode ray tube, so that a touch phenomenon occurs because the outer edge of each electrode to which different voltages are applied and its distance are sufficiently close to each other. This is a cause of lowering the breakdown voltage characteristic, which is a discharge phenomenon in, and the electron beam focusing characteristic of the electron gun.

In addition, Korean Patent Publication No. 97-30017 discloses a so-called knocking method that removes foreign substances on electrodes by electrolytically polishing each electrode and applying high pressure to the electrode through a multi-step process to improve the breakdown voltage characteristics of the cathode ray tube. This method can improve the withstand voltage characteristics by instantaneously removing foreign matters inside the cathode ray tube, but it is easier to discharge the electric field from the electropolished electrode, which is caused by strays caused by foreign matters that may be generated during operation of the cathode ray tube. It is not a measure to fundamentally solve the discharge problem caused by the shape of electron gun.

Accordingly, an object of the present invention is to expand a portion of a rectangular glass shaped bead that supports each electrode of the electron gun to form an insulated protrusion, and to install a connector for voltage application on the top of the insulated protrusion, thereby providing a connector and each electrode. It is to provide a cathode ray tube electron gun that can prevent the discharge and touch phenomenon of the liver to enhance the life and withstand voltage characteristics and electron beam focusing characteristics of the electron gun.

Technical means of the present invention for achieving the above object is a cathode having a predetermined heater to emit electrons, a plurality of grid electrodes for controlling the radiation amount, acceleration and focus of the electrons, and the image of the plurality of grid electrodes An electron gun having a plurality of insulating supports installed at the bottom to hold and couple each electrode at a predetermined interval, and a connector for applying a voltage applied from an external stem pin to the corresponding electrode, wherein the projecting portion is formed on one side of the insulating support. It is characterized in that the installation and mounting or attaching the connector on the surface of the protrusion.

1 is a side view showing a cross section of a general color cathode ray tube,

2 is a plan view showing the structure of a general electron gun,

3 shows lens characteristics of a general deflection yoke.

4 illustrates lens characteristics of a general electron gun and a deflection yoke,

5 shows a grid electrode and an insulator support portion of the electron gun according to the prior art, FIG. 5A is a plan view, and FIG. 5B is a side view,

FIG. 6 shows a partial structure of an electron gun according to the present invention. FIG. 6A is a plan view, and FIG. 6B is a side view.

7 is a view showing the shape of the insulating support according to an embodiment of the present invention, Figure 7a is a plan view, Figure 7b is a side view.

Explanation of symbols on the main parts of the drawings

40: electron gun 41: cathode

42-1 to 42-6: grid electrodes 43: shield cup

45: glass bead 46: protrusion

47: stem 48: stem pin

49: connector

Hereinafter, the present invention will be described in more detail with reference to the accompanying drawings.

FIG. 6 shows a partial structure of an electron gun according to the present invention. FIG. 6A is a plan view, FIG. 6B is a side view, and the same view shows a plurality of grid electrodes 42-1 to 42-6 and an insulating support 45. And a connector 49.

The plurality of grid electrodes 42-1 to 42-6 are provided in proximity to a predetermined cathode 41 to control the amount of radiation of the electron beam emitted from the cathode, and to the first electrode. A second electrode 42-2 which is installed in close proximity to accelerate the emitted electron beam, and third and fourth electrodes 42-3 and 42-4 which are installed in proximity to the second electrode to form a shear focusing lens; And fifth and sixth electrodes 42-5 and 42-6 which are provided in close proximity to the fourth electrode to form the electrostatic focusing lens, which are grid electrodes 42-1 to 42-6. It is installed while maintaining a constant distance from each other by the insulating support 45 of the insulating material installed on the upper and lower ends of the).

That is, upper and lower edge portions of each of the electrodes 42-1 to 42-6 are embedded in the insulating support 45 provided at the upper and lower ends thereof, and are fixed while maintaining a constant distance between the electrodes.

In addition, a protrusion 46 of the same material is formed on one side of the insulating support 45 to connect the stem pin 48 shown in FIG. 2 to the voltage application connector 49 for connecting the grid electrode. By being seated or attached to the upper end, discharge and touch phenomenon between the connector 49 and the electrodes 42-1 to 42-5 'can be more reliably prevented.

7 is a view showing the shape of the insulating support according to an embodiment of the present invention, Figure 7a is a plan view, Figure 7b is a side view, the same figure is the insulating support 45, the protrusion 46 and the connector 49. Is shown.

As shown in FIG. 7, a protruding portion 46 is formed on one side of the insulating support 45 to be integrally formed with the same material as the insulating support 45, and the connector 49 is installed to pass through the upper surface of the protruding portion.

The protrusion 49 is formed in a substantially rectangular shape extending horizontally along the direction of the tube axis Z, and the thickness of the protrusion 49 is thinner than that of the insulating support 45.

In addition, the dimension of each part with respect to the protrusion part 46 is prescribed | regulated as following Table 1.

Protrusion of Insulation Support part size A 0.5 to 4.5 mm B 0.5 to 2.0 mm C 14-20 mm

Here, when the dimension A of the width of the protrusion 46 is 4.5 mm or more, contact with the inner wall of the neck occurs, and the dimension of B, the thickness of the protrusion, is 0.5 mm or less, or the length of C, the length of the protrusion in the direction of the tube axis Z. Is more than 20 mm, cracking is likely to occur, and at least the length C of the protrusion is larger than the distance from the end of the cathode 41 side of the insulating support 45 to the first electrode 42-1.

In addition, the insulating support 45 is installed at the upper and lower ends of the grid electrode, respectively, as shown in Figure 6, the protrusion 46 is most preferably formed on the cathode side of the upper insulating support of the upper and lower insulating support 45. .

As described above, the insulating protrusions 46 are formed on one side of the insulating support 45 and the connector 49 for applying voltage is installed on the upper end of the protrusions 46 to install the connector 49 and each electrode 42. The unstable field emission at -1 to 42-6) causes the electrons to collide with the micromolecules that may be present inside the cathode ray tube, resulting in ionization, and the cations and electrons generated by the ionization collide with another molecule. By repeating the process such as four electrons can be prevented the phenomenon of avalanche that can occur.

In addition, the inside of the cathode ray tube is almost insulated in a high vacuum state of about 10 ^-7 Torr, but the higher the number of collision electrons, the lower the breakdown voltage caused by the avalanche, and so-called stray phenomenon occurs in the cathode ray tube. This reduces the lifespan and withstand voltage characteristics of the cathode ray tube due to the damage of the cathode surface and the electron beam focusing characteristics of the electron gun, which can also be prevented.

Therefore, in the present invention, it is possible to reduce the lifespan, the withstand voltage characteristics, and the electron beam focusing characteristics due to the damage of the cathode surface by the discharge in the cathode ray tube.

Although specific embodiments of the present invention have been described and illustrated above, the present invention may be variously modified and implemented by those skilled in the art, such as forming the connector attachment protrusions on the upper and lower insulating supports, respectively, or on both sides of the insulating support. It is self-evident.

Such modified embodiments should not be individually understood from the technical spirit or the prospect of the present invention, and such modified embodiments should fall within the appended claims of the present invention.

Accordingly, in the present invention, an insulating protrusion is formed at one end of the insulating support so that an insulating film can be inserted between the connector to which the variable voltage is applied and the outer surface of each electrode inserted into the insulating support to support the electron gun, and the protrusion is formed on the surface thereof. By installing a connector for applying a dynamic voltage in the connector, it is possible to prevent collision of induced electrons due to touch phenomenon of the connector and each electrode and unstable field emission from the connector and each electrode, thereby improving the lifetime and withstand voltage characteristics of the electron gun. .

Claims (5)

A cathode provided with a predetermined heater to emit electrons, a plurality of grid electrodes for controlling the radiation amount, acceleration, and focus of the electrons, and upper and lower ends of the plurality of grid electrodes to maintain each electrode at a predetermined interval; In the electron gun having a plurality of insulating support to be coupled and a connector for applying a voltage applied from the external stem pin to the electrode, An electron gun for a cathode ray tube, characterized in that a protrusion is formed on one side of the insulating support and the connector is provided on the surface of the protrusion. The method of claim 1, The protrusion, An electron gun for cathode ray tubes, the width of which is 0.5 to 4.5 mm, the thickness of 0.5 to 2 mm, and the length of the tube axis direction is approximately 14 to 20 mm. The method of claim 1, The protrusion, Electron gun for cathode ray tube, characterized in that the substantially rectangular shape extending horizontally toward the grid electrode from the cathode side of the end of the insulating support. The method of claim 1, The protrusion, Electron gun for cathode ray tube, characterized in that installed on the side of the upper insulating support of the plurality of insulating support. The method of claim 1, The protrusion, Electron gun for cathode ray tube, characterized in that made of the same insulating material as the material of the insulating support.