JPS61250934A - Inner resistor of cathode-ray tube - Google Patents

Abstract

PURPOSE:To prevent variation of resistance due to adhesion of evaporated metal by providing a resistor layer on one face of ceramic substrate then covering with non-porous first insulation film while providing non-porous second insulation film on the other face of the substrate. CONSTITUTION:A high voltage electrode terminal 2, a convergence electrode terminal 3 and an earth electrode terminal 4 are arranged on the surface 1a of a ceramic substrate 1 then a voltage dividing resistor layer 5 composed of resistor layers 5a-5c in zigzag pattern is arranged between them. The upper face of said layer 5 is covered with non-porous insulation film 6 composed of lead glass paste. Insulation film 20 composed of lead glass paste is provided at the necessary position on the rear face 1b to form an inner resistor to be assembled in the cathode-ray tube together with an electron gun structure. Consequently, the vapored metal to be produced through the inter-electrode discharge will adhere onto the insulation film 20 thus to eliminate influence onto the voltage division resistor layer 5.

Description

[Detailed description of the invention] The present invention will be explained in the following order.

A. Field of industrial application B. Overview of the invention C. Prior art D. Problem to be solved by the invention E. Means for solving the problem F. Effect G. Example c-i First example (Fig. 1, Figure 2) G-2 2nd
Example (Figure 3) G-3 Third Example (Figure 4) G-4 Comparative test results G-5 Additional effects (Figure 5) Effects of the invention A Industrial application field book The present invention relates to a built-in resistor that is incorporated together with an electron gun assembly into a tube such as a color cathode ray tube.

B. Summary of the Invention The present invention provides a built-in cathode ray tube equipped with a ceramic substrate that is incorporated together with an electron gun assembly into the tube body of the cathode ray tube and supplies the electron gun assembly with a voltage obtained by dividing the anode voltage of the cathode ray tube. In a resistor, in addition to a non-porous insulating film that covers a resistor layer formed on a ceramic substrate, a first surface of the ceramic substrate on which a resistor layer is formed and a first
By depositing a non-porous additional insulating coating on at least one of the second surfaces facing the surface of This prevents evaporated metal, which is caused by the generation of a flow of water and adheres to the ceramic substrate, from penetrating into the resistor layer, thereby suppressing changes in the resistance value of the resistor layer.

C. Prior Art Conventionally, in color cathode ray tubes and the like used in color television receivers, in addition to the anode voltage, high voltages are required to be supplied to, for example, convergence electrodes and focus electrodes.

In such a case, it has been proposed to incorporate a resistor for voltage division into the tube together with the electron gun structure as a built-in resistor, thereby dividing the anode voltage to obtain the respective high voltages. As an example of the conventional built-in resistor used, those shown in FIGS. 6 and 7 are known.

FIG. 6 shows the conventional built-in resistor 7 seen through from above the insulating coating forming the outer surface, and FIG. 7 shows the entire side view of the conventional built-in resistor 7.

In the built-in resistor 7 shown in FIGS. 6 and 7, a terminal portion is formed by depositing a conductive layer on a ceramic substrate 1, that is, a high voltage electrode terminal 2 to which a high voltage is supplied.
．． A convergence electrode terminal (hereinafter referred to as CV electrode terminal) 3 and a ground electrode terminal 4 from which a high voltage for the convergence electrode, that is, a convergence voltage can be obtained, and a ground electrode terminal 4 are provided, and between the CV electrode terminal 3 and the ground electrode terminal 4, , a resistor layer 5a having a zigzag pattern having a required resistance value, a resistor layer 5b having the same required resistance value between the high voltage electrode terminal 2 and the CV electrode terminal 3; A resistor layer 5c for fine adjustment is deposited between the layers 5a and 5b and the CV electrode terminal 3, respectively, to form a voltage dividing resistor layer 5. And in the shaded area in Figure 6,
An insulating coating 6 made of lead glass or the like is applied to cover the voltage dividing resistor layer 5. The fine adjustment resistor layer 5c is provided so that the resistance value of the resistors H5a and 5b between each terminal can be adjusted by removing a part of it in the manufacturing process of the built-in resistor 7. ing.

FIG. 8 shows a state in which the built-in resistor 7 having such a configuration is incorporated into a color cathode ray tube. Here, an electron gun assembly 9 is disposed within the neck portion a of the tube body 8, and this electron gun assembly 9 has a first grid electrode Gl and a second grid electrode in common for the three cathodes K. G2. Third grid electrode G3. Fourth grid electrode G4 and fifth grid electrode G
5 are sequentially arranged on the same axis. and,
Convergence means 10 is arranged downstream of the fifth grid electrode G5. Each electrode G1. G2゜G3. G
4. G5 and the convergence means 10 are mechanically connected by a beep ink crow 11 while maintaining a predetermined positional relationship with each other, and the third grid electrode G3 and the fifth grid electrode G5 are connected to each other by a conductive wire 13. electrically connected. Further, the convergence means 1o is electrically connected to the fifth grid electrode G5 via the conductive plate 14, and the inner deflection electrode plates 10a and 10 facing each other are electrically connected to the fifth grid electrode G5 via the conductive plate 14.
b, and outer deflection electrode plates 1°C and 10d disposed on the outside facing the electrode plates 10a and 10b.

A built-in resistor 7 as shown in FIGS. 6 and 7 is attached to such an electron gun assembly 9, and the high voltage electrode terminal 2 of this built-in resistor 7 is connected to the fifth grid electrode G.
5 and the electrically conductive attachment is connected via a piece 12. A graphite conductive film 15 extending to the inner wall of the neck portion 8a is adhered to the inner wall of the funnel portion 8b of the tube body 8, and a high-pressure supply button, that is, an anode button (not shown) provided on the funnel portion 8b. Anode voltage is supplied through. The conductive plate 14 is provided with a conductive spring 16, and when the conductive spring 16 comes into contact with the graphite conductive H15, the fifth grid electrode 05. Third grid electrode G3. Convergence means 1
An anode voltage is supplied to the inner deflection electrode plates 10a and 10b of 0 and the high voltage electrode terminal 2 of the built-in resistor 7.

CV@pole terminal 3 of built-in resistor 7 is conductive mounted on piece 17
The outer deflection electrode plate 1 of the convergence means 10 via
0c and 10d, and the convergence voltage obtained at the CV electrode terminal 3 by dividing the anode voltage by the resistor layers 5a and 5b is connected to the outer deflection electrode plates 10c and 10d.
supplied to

Further, the ground electrode terminal 4 of the built-in resistor 7 is connected to a ground electrode terminal pin 19 embedded through the stem 18 at the base of the neck lip 83 of the tube body 8, and the ground electrode terminal 4 is connected directly or via an external adjustment resistor. Grounded.

In this way, the built-in resistor 7, which is incorporated together with the electron gun assembly 9 in the tube body 8 of the color cathode ray tube, controls the external deflection of the convergence means 10 through the C electrode terminal 3 during the actual operation of the color cathode ray tube. In order to make the convergence voltage supplied to the electrode plates 10C and 10d stable and have a predetermined voltage value, changes in the resistance values of the resistor layers 5a and 5b of the voltage dividing resistor layer 5 are minimized. It is hoped that this will be done.

D Problems to be Solved by the Invention As described above, the neck portion a of the tube body 8 of a color cathode ray tube constructed as shown in FIGS. 6 and 7 and as shown in FIG. The built-in resistor 7 installed and incorporated in the electron gun structure 9 is connected to the tube body 8 of the color cathode ray tube.
Inside, the ceramic substrate 1 is arranged to face each grid electrode of the electron gun assembly 9. and,
The built-in resistor 7 in the tube body 8 of the color cathode ray tube is connected to the discharge that occurs between the grid electrodes of the electron gun assembly 9, or from the low voltage electrode side to the high voltage electrode, which is called a stray, during actual operation of the color cathode ray tube. Evaporated metals (iron, nickel, chromium) generated when the metal material such as stainless steel that forms each grid electrode is cooled due to the continuous flow of emitted electrons to the side, etc.
It is assumed that it is attached to the surface covered with I6 and without C, that is, the surface opposite to the surface on which the voltage dividing resistor layer 5 is formed. The metal adhered to one surface of the ceramic substrate 1 of the built-in resistor 7 in this way penetrates into the inner surface of the ceramic substrate 1 (because it is porous) and penetrates into the other surface of the ceramic substrate 1. reaches the partial voltage resistor layer 5 formed thereon, and as a result, the inner M
The problem with the resistor 7 is that it causes a change in the resistance value of the voltage-dividing resistor layer 5 .

In view of these points, the present invention has a structure in which a resistor layer having a predetermined pattern is formed on a ceramic substrate and this resistor layer is covered with an insulating film, so that electrons can be transferred into the body of a cathode ray tube. It is assumed that the cathode ray tube is installed together with the gun assembly, and when the cathode ray tube is in actual operation, the discharge generated between the electrodes of the electron gun assembly, or the adhesion of evaporated metal from each electrode of the electron gun assembly due to stray etc. An object of the present invention is to provide a built-in resistor for a cathode ray tube, which can effectively suppress a change in the resistance value of a resistor layer formed on a ceramic substrate even when the above occurs.

E. Means for Solving the Problems In order to achieve the above-mentioned object, the built-in resistor of a cathode ray tube according to the present invention includes a ceramic substrate and a non-conductive material adhered to at least one of the opposing surfaces of the ceramic substrate. A resistor formed in a predetermined pattern between a porous first insulating film and a plurality of electrode terminals arranged on one or the other of the facing surfaces of the ceramic substrate or on the first insulating film. and a non-porous second insulating coating disposed on a ceramic substrate to cover the resistor layer.

The built-in resistor of the cathode ray tube according to the present invention configured as described above is used by being incorporated into the cathode ray tube together with the electron gun assembly, and when the cathode ray tube is in operation, the resistor between the electrodes of the electron gun assembly is If evaporated metal is deposited from each electrode of the electron gun assembly due to discharge or stray generated in the The coating, together with a non-porous second insulating coating disposed on the ceramic substrate to cover the resistor layer, allows the deposited metal to penetrate inside the ceramic substrate towards the resistor layer or from the ceramic substrate. It plays a role in preventing contamination into the resistor layer formed thereon.

For this reason, when the built-in resistor of the cathode ray tube according to the present invention is incorporated and used together with the cathode ray tube 6 and the electron gun assembly, it is possible to prevent the electron gun assembly from being damaged due to discharge or stray occurring between the electrodes of the electron gun assembly. Even if evaporated metal adheres from each electrode, etc., it can prevent the adhering metal from entering the resistor layer, and as a result, it can minimize changes in the resistance value of the resistor layer. becomes.

G Example G-1 First Example (Figures 1 and 2) Figure 1 shows the back side of an example of the built-in resistor of the cathode ray tube according to the present invention, and Figure 2 shows the back side of an example of the built-in resistor of the cathode ray tube according to the present invention. A cross section according to n-ng is shown in FIG. This example has a part configured similarly to the built-in resistor 7 shown in FIGS. 6 and 7, and the first
In FIGS. 6 and 7, parts corresponding to those shown in FIGS. 6 and 7 are designated by the same reference numerals as in FIGS. 6 and 7, and detailed explanations thereof will be omitted. be done.

In the example shown in FIGS. 1 and 2, the ceramic substrate 1 is, for example, a 98% alumina plate, and a high-voltage electrode terminal 2 and a CV electrode terminal 3 are disposed on one of the opposing surfaces la. and a ground electrode terminal 4,
Further, between the CV electrode terminal 3 and the earth electrode terminal 4, a resistor layer 5a formed in a zigzag pattern having a required resistance value is provided, and between the high voltage electrode terminal 2 and the CV electrode terminal 3, a resistor layer 5a is provided as required. The resistor layer 5b has a resistance value of .

Further, fine adjustment resistor layers 5c are arranged between the resistor layers 5a and 5b and the CV electrode terminal 3, respectively, to form a voltage dividing resistor layer 5. An insulating coating 6 is provided on the surface la side of the ceramic substrate 1, which covers the voltage dividing resistor layer 5 and exposes the high voltage electrode terminal 2, the CV electrode terminal 3, and the earth electrode terminal 4. 6 is a non-porous layer formed by firing lead glass paste, for example.

In this way, the front side of the built-in resistor according to this example is configured.

And on the back side of the built-in resistor according to this example,
Surface '1 of ceramic substrate 1 on which voltage dividing resistor layer 5 is formed
An insulating coating 2° is applied to the surface 1b opposite to a. This insulating coating 2o is an insulating coating 6 provided on the surface 1a.
Similarly, it is composed of a non-porous layer formed by firing lead glass paste, for example. In the process of forming such a non-porous layer, the material such as lead glass paste that forms this non-porous layer is a porous ceramic material.
.

It is preferable that the ceramic substrate 1 penetrates into the interior of the ceramic substrate 1 from the surface 1b and acts so as to cause the ceramic substrate 1 to lose its porosity in that area. Further, in this example, the area to which the insulating coating 2o is adhered to the surface 1b corresponds to, for example, the range in which the zigzag pattern of the resistor layer 5a disposed on the surface la extends, and such area is The built-in resistor according to this example, as shown in FIG.
When installed in the same manner as the built-in resistor 7 described above,
This includes the position from the position corresponding to the first grid electrode G1 to the position corresponding to the middle part of the fifth grid electrode G5.

The built-in resistor shown in FIGS. 1 and 2 having such a configuration can be used, for example, in an electron gun in the neck part a of the tube body 8 of a color cathode ray tube as shown in FIG. An insulating coating 6 is attached to the structure 9 with the same arrangement and connection relationship as the built-in resistor 7 described above, and covers the voltage dividing resistor layer 5 formed on the ceramic substrate l.
It is assembled into the tube body 8 of the color cathode ray tube so as to face the inner wall surface of the tube a, and when the color cathode ray tube is in operation,
As in the case of the built-in resistor 7, the convergence voltage obtained by dividing the anode voltage supplied to the high voltage electrode terminal 2 by the voltage dividing resistor layer 5 is deflected to the outside of the convergence means 10 through the C electrode terminal 3. It shall be supplied to the electrodes '[10c and 10d.

In this way, when the built-in resistor shown in FIGS. 1 and 2 is installed and incorporated in the electron gun assembly 9 within the neck portion a of the tube body 8 of the color cathode ray tube shown in FIG. , its back side, that is, its ceramic base It1i1
The surface lb side of the electron gun assembly 9 is arranged to face each grid electrode of the electron gun assembly 9.

For this reason, during actual operation of the color cathode ray tube, evaporated metal is generated when the metal material such as stainless steel forming each grid electrode evaporates due to discharge or stray that occurs between each grid electrode of the electron gun assembly 9. (iron, nickel, chromium, etc.) is assumed to adhere to the surface lb side of the ceramic substrate 1. In such a case, the deposition of evaporated metal from each grid electrode of the electron gun assembly 9 is limited to the area from the position corresponding to the first grid electrode G1 to the position corresponding to the middle part of the fifth grid electrode G5, that is, to the ceramic substrate. 1
It occurs in the area where the insulating coating 20 is deposited on the surface 1b, and hardly occurs in other parts.

Therefore, the evaporated metal is deposited on the surface 1b of the ceramic substrate 1 on the surface of the insulating coating 20.

In this case, like the insulating coating 6, the insulating coating 20 is a non-porous layer, so the metal attached to its surface cannot penetrate into its interior. That is, the metal attached to the surface lb side of the ceramic substrate 1 is removed from the insulating coating 20.
As a result, penetration into the interior of the ceramic substrate 1 is prevented, and therefore, reaching the voltage dividing resistor layer 5 formed on the side 1a of the ceramic substrate 1 is prevented. Therefore, even if evaporated metal is deposited on the lb side of the ceramic substrate 10, the resistance value of the voltage dividing resistor layer 5 hardly changes due to this.

Note that when the insulating coating 20 is provided on the surface 1b of the ceramic substrate 1, unlike the above-mentioned example, the insulating coating 20 may be made to cover substantially the entire surface 1b, and the insulating coating 20 may be provided on the surface 1b of the ceramic substrate 1.
Whether 0 is provided in a selected area of the surface 1b as in the above example or provided on substantially the entire surface of the surface 1b may be arbitrarily selected by taking into consideration the effects and advantages in manufacturing. .

G-2 Second Embodiment (FIG. 3) FIG. 3 shows another example of the built-in resistor of a cathode ray tube according to the present invention, with a cross section corresponding to the cross section shown in FIG. 2. In FIG. 3, parts corresponding to those shown in FIG. 2 are designated with the same reference numerals as in FIG.
Duplicate explanations about them will be omitted.

In this example, the insulating coating 20 is replaced with the insulating coating 20 in the example shown in FIGS. 1 and 2 above.
An insulated wave W#30 corresponding to
a, covering almost the entire surface thereof. A high voltage electrode terminal 2, a CV electrode terminal 3, and a ground electrode terminal 4 are provided on an insulating coating 30 deposited on the surface 1a of the ceramic substrate 1. A resistor layer 5a having a zigzag pattern having a required resistance value is provided between the high voltage electrode terminal 2 and the CV electrode terminal 3, and a resistor layer 5b having the same required resistance value is provided between the high voltage electrode terminal 2 and the CV electrode terminal 3. Further, fine adjustment resistor layers 5c are arranged between the resistor layers 5a and 5b and the CV electrode terminal 3, respectively, to form a voltage dividing resistor layer 5. Moreover, on the insulating coating 30,
An insulating coating 6 is provided that covers the voltage dividing resistor layer 5 and exposes the high voltage electrode terminal 2, the CV electrode terminal 3, and the earth electrode terminal 4.

This insulating coating 30 is also composed of a non-porous layer formed by firing lead glass paste, for example. however,
In this example, after the insulating coating 30 is formed on the surface la of the ceramic substrate 1, each electrode terminal 2.
3 and 4, the voltage-dividing resistor layer 5, and the insulating coating 6 will be formed by firing, so the material such as lead glass paste used for forming the insulating coating 30 should be selected from each electrode terminal 2.3. A material having a softening temperature at which it does not soften when forming the resistor layer 5 and the insulation film 6 by firing is selected.

In this example, in the same way as the example shown in FIGS. 1 and 2, for example, the electron gun assembly 9 in the neck portion a of the tube body 8 of a color cathode ray tube as shown in FIG. installed and used. In this case, during actual operation of the color cathode ray tube, evaporated metal is generated when the metal material forming each grid electrode evaporates due to discharge or stray that occurs between each grid electrode of the electron gun assembly 9. , and the attached metal penetrates into the inside of the ceramic substrate 1 from the surface 1b, but the metal that has penetrated into the inside of the ceramic substrate 1 is coated on the surface 1a of the ceramic substrate 1. In other words, the metal that has penetrated into the ceramic substrate 1 cannot pass through the insulating film 30 that has been applied.
Therefore, even if evaporated metal is deposited on the surface lb side of the ceramic substrate 1, the resistance value of the partial voltage resistance layer 5 hardly changes due to it.

G-3 Third Embodiment (FIG. 4) FIG. 4 shows still another example of the built-in resistor of a cathode ray tube according to the present invention, with a cross section corresponding to the cross section shown in FIG. 3. In FIG. 4, parts corresponding to the parts shown in FIG. 3 are designated by the same reference numerals as in FIG. 3, and redundant explanation thereof will be omitted.

This example includes the insulating coating 20 in the example shown in FIG. 3 described above, and the example shown in FIGS.
This corresponds to a case in which the ceramic substrate 1 is expanded and adhered to substantially the entire surface 1b of the ceramic substrate 1.

And, in this example as well, in the same way as each side described above, for example,
It is used by being attached to an electron gun assembly 9 within a neck portion a of a tube body 8 of a color cathode ray tube as shown in FIG. In this case, during the actual operation of the color cathode ray tube, the discharge generated between each grid electrode of the electron gun structure 9,
Alternatively, the metal material forming each grid electrode may evaporate due to stray, and the surface lb of the ceramic substrate 1
Regarding the prevention of the influence of evaporated metal adhering to the side on the partial voltage resistor layer 5, the example shown in FIGS. 1 and 2 and the example shown in FIG.
This will have the same effect as the example shown in the figure.

G-4 comparative test results Here, the example shown in FIGS. 1 and 2 (first example), the example shown in FIG. 3 (second example), and the example shown in FIGS. Conventional built-in resistor shown in Figure 7 (conventional example)
A plurality of samples were taken as test samples for each of the above, and a certain amount of metal was deposited using a sputtering method on certain parts of the respective ceramic bases IIN and 1 where the partial voltage resistor layer 5 was not placed. After applying a high voltage of 34 kV to the high voltage electrode terminal 2 and conducting a running test for 5000 hours, the resistance value of the voltage dividing resistor layer 5 before being subjected to the running test was set as Rb, and the resistance value before being subjected to the running test was set as Rb. The resistance value after is set as Ra, 1Rb-Ra
The results of determining the resistance value change/ΔR expressed as I/Rb/100”ΔR were as follows.

Maximum value of ΔR Minimum value Average value of ΔR Conventional example 15% 0.5% 4% First example 1.5% 0% 0.5% Second
Example 1.6% 0% 0.6%In addition, during such a comparative test, the thickness of the insulating coatings 20 and 30 provided in the first example and the second example, respectively, was 25%.
It was taken as μm.

From the results of such comparative tests, it is clear that the built-in resistor of the cathode ray tube according to the present invention has an extremely excellent effect in preventing the influence of metal attached to the surface of the ceramic substrate 1 on the voltage dividing resistor layer 5. is understood.

G-5 Additional Effects (Fig. 5) In addition, in a color cathode ray tube as shown in Fig. 8, for example, if there are sharp protrusions on each part of the electron gun assembly 9, it may be difficult to use the color cathode ray tube in actual use. This will result in an undesired electrical discharge. Therefore, in the manufacturing process, the electron gun assembly 9
For areas where electrical discharge is likely to occur, such as sharp protrusions, by melting and molding with electrical discharge in advance,
Knocking treatment is performed for the purpose of stabilizing the operation of the finished product during actual use. In such a knocking treatment process, for example, a high voltage (knocking voltage) that is two to three times higher than that during actual operation of the color cathode ray tube is applied to the third grid electrode G3. The voltage is applied to the fifth grid electrode G5 and the high voltage electrode terminal 2 of the built-in resistor, and the voltage is applied to the first grid electrode G5. The second and fourth grid electrodes Gl, G2, and G4 are grounded. During this knocking process,
The surface of the insulating film 6 covering the voltage-dividing resistor layer 5 of the built-in resistor is charged to a relatively high potential except for a part,
A larger potential difference will be applied to this insulating coating 6, especially near the third grid electrode G3, compared to during actual operation.

Therefore, a potential difference exceeding the withstand voltage of the insulating coating 6 is applied to the built-in resistor near the third grid electrode G3 of the electron gun assembly 9, causing insulation deterioration or dielectric breakdown of the insulating coating 6, and as a result, There is a possibility that the resistance value of the voltage dividing resistor layer 5 may change.

The built-in resistor of the cathode ray tube according to the present invention described above also exhibits an excellent effect in suppressing changes in the resistance value of the voltage dividing resistor layer caused in connection with the knocking treatment of the cathode ray tube. has been experimentally confirmed.

For example, the results of a comparative test using a plurality of examples shown in FIGS. 1 and 2 and a plurality of conventional built-in resistors as shown in FIGS. 6 and 7 as test samples, respectively. was as shown in FIG. In FIG. 5, the vertical axis is the resistance value Rnb of the voltage dividing resistor layer 5 before being subjected to the knocking process, and the resistance value after being subjected to the knocking process is Rna, 1Rnb-Rna l/Rnb・100= shows the resistance value change obtained as ΔR・KΔR, and the circles indicate the results of the example test samples shown in Figures 1 and 2.
Further, the Δ marks indicate the results of test samples of conventional built-in resistors. The knocking voltage supply conditions to the high-voltage electrode terminal 2 of each built-in resistor during the knocking process are as follows: First, a DC voltage of 60 kV is applied for 2 milliseconds at a cycle of 20 milliseconds for 1 minute, and then To,
A period of applying a DC voltage of 50 kV for 1 second at a cycle of 2 seconds was continued for 4 minutes, and then a period of 60 'kV was applied again.
A period in which a DC voltage of V was applied for 2 milliseconds at a cycle of 20 milliseconds was continued for 1 minute.

The results of this comparative test show that the resistance value change, KΔR, of each of the seven test samples of the conventional built-in resistor, indicated by the Δ symbol, is distributed in the range of 1.3 to 4.2%, and the average was approximately 2.7 percent, whereas the resistance value change/KΔR of each of the 10 test samples shown in Figures 1 and 2, indicated by the Q mark, was almost zero, including zero is 0
．． It shows that the value converged to 4% or less and the average was about 0.18%. From this, the built-in resistor of the cathode ray tube according to the present invention is effective in the knocking treatment of the cathode ray tube. It is understood that the resulting change in resistance value of the voltage-dividing resistor layer can be effectively suppressed.

Effects of the Invention H As is clear from the above explanation, the built-in resistor of the cathode ray tube according to the present invention has a resistor layer having a predetermined pattern formed on a ceramic substrate, and this resistor layer is covered with an insulating film. The cathode ray tube is designed to have a configuration in which it is installed together with the electron gun assembly in the tube body of the cathode ray tube, and furthermore, during actual operation of the cathode ray tube, there is no risk of discharge or stray occurring between the electrodes of the electron gun assembly. Even if evaporated metal from the electrodes of the electron gun assembly adheres to the ceramic substrate, the non-porous insulating coating applied to at least one of the facing surfaces of the ceramic substrate prevents the adhered metal from sticking to the ceramic substrate. The resistor formed on the ceramic substrate is prevented from penetrating inside the ceramic substrate toward the voltage-dividing resistor layer, or from entering the resistor layer formed on it from within the ceramic substrate. Changes in the resistance value of the layer can be effectively suppressed.

Therefore, when the built-in resistor of the cathode ray tube according to the present invention is used to supply a convergence voltage formed by dividing the anode voltage to the convergence means provided in the color cathode ray tube, it is extremely stable. A state is obtained in which a convergence operation is performed.

[Brief explanation of drawings]

FIG. 1 is a back view showing an example of the built-in resistor of a cathode ray tube according to the present invention, FIG. 2 is a sectional view taken along the line ■-■ in FIG. 1, and FIGS. 3 and 4 are respectively according to the present invention. A cross-sectional view showing another example of a built-in resistor of a cathode ray tube, FIG. 5 is a diagram for explaining the function and effect of the built-in resistor of a cathode ray tube according to the present invention, and FIGS. 6 and 7 are diagrams showing a conventional one. FIG. 8 is a plan view and a side view showing the built-in resistor of the cathode ray tube of FIG. In the figure, 1 is a ceramic substrate, 2 is a high voltage electrode terminal, 3 is a convergence electrode terminal, 4 is a ground electrode terminal, 5 is a voltage dividing resistor layer, 9 is an electron gun structure, and 6° 20 and 30 are insulating coatings. . XX cross-sectional view 2nd cross-sectional view of shot 1 Figure 3 A diagram showing comparative test results Figure 5

Claims (1)

[Claims] A ceramic substrate; and a non-porous first insulating coating deposited on at least one of a first surface and a second surface opposite the first surface of the ceramic substrate. and a resistor layer formed in a predetermined pattern between a plurality of electrode terminals arranged on the first or second surface of the ceramic substrate or on the first insulating film, and the ceramic substrate. and a non-porous second insulating film provided to cover the resistor layer.