JPH01117244A - Cathode-ray tube device - Google Patents

Abstract

PURPOSE:To save power consumption and improve a resolution by forming a linear cathod via the coverage of a coil-shaped heater with a direct thermion emission material and positioning the lengthwise direction thereof along the vertical direction of a fluorescent plane. CONSTITUTION:A heater wire 21 of extremely small thermal capacity is so wound in the form of a coil as to be compact and clear of each other. A direct thermion emission material 23 is bonded to the coil part and a cathode 24 is thereby formed together with terminal pins 26a and 26b. The cathode 24 has high resistance and small thermal capacity at the coil-shaped part thereof. The cathode 24, therefore, reaches the required temperature with small electric power and in addition, coil density does not change at the time of heating the cathode 24. Consequently, the cathode 24 comes to have a uniform temperature and operate stably. The cathode 24 is so positioned as to have the length- wise direction thereof perpendicular to a fluorescent plane. As a result, a horizontal resolution becomes good and as the feeling of a vertical resolution is normally weaker than a horizontal resolution, the resolution is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a cathode ray tube device having an electron gun having a linear cathode and a fluorescent surface formed with a phosphor layer. Cathode
The aim is to reduce the power consumption of the cathode ray tube device by improving this, and to increase the resolution of the screen by improving the positional relationship of the cathode with respect to the fluorescent surface.

Generally, a directly heated cathode is used as a low power consumption cathode used in a cathode ray tube device. Figures 1 to 3 show an example of the cathode structure, which has a central opening (1).
Annular platform of ceramic insulating support (2) with! (
3) A ribbon-shaped heater (4) with a relatively small coefficient of thermal expansion is placed on top.
) is stretched, and in the center of the heater (4), a base metal (5) of, for example, nickel and a metal oxide (e.g. (Ba, Ca, Sr) 0s) (6
) is deposited on both ends of the heater (4), and a pair of lead terminal pins ( 10a)
and (10b), the base metal (5) is heated by energization of the heater (4), and thermionic electrons are emitted from the oxide (6).

However, in such a cathode assembly (11), the base metal (5) is welded onto the heater (4), so there is a limit to low power consumption, and the ceramic annular base (3) Since the heater (4) is in contact with the cathode, variations in contact cause a difference in so-called cathode temperature, which tends to cause variations in life. Furthermore, the distance d between the cathode and the first grid (control grid) in the electron gun increases due to the slow rise of thermionic radiation, the tendency of the heater (4) to break, and the thermal expansion of the heater (4). 1 changes, and the cutoff changes.

In view of the above-mentioned points, the present invention eliminates the above-mentioned drawbacks and provides a cathode ray tube device which is particularly equipped with a cathode of ultra-low power consumption and also has good resolution.

Hereinafter, one embodiment of a cathode ray tube device according to the present invention will be described with reference to the drawings.

4 and 5 show a directly heated cathode applied to the present invention. This directly heated cathode (24) is made by winding the heater wire (21), which has an extremely small heat capacity, into a coil shape in the necessary portions tightly and without contacting each other, and the coil aB (
22) directly thermionic emitting substances, such as (Ba,
Ca, 5r) 0. The metal oxide (23) is deposited by electrodeposition or spraying. In this case, the heater wire (21) is made of a material that acts as a reducing agent for the oxide (23) and has high high-temperature strength, high specific resistance, and low coefficient of thermal expansion, such as tungsten (W). It is possible to use a heater wire.

As shown in FIGS. 6 and 7, both ends of the heater wire (21) of this cathode (24) are connected to ceramic insulating supports (
A so-called cathode structure (27) is formed by electrically and mechanically fixing the pair of lead terminal pins (26a) and (2611) planted on the terminals (25) by crimping, caulking, welding, etc.
Configure. (37) is an opening for degassing provided in the center of the insulating support (25).

Note that the heater wire (21) of the cathode (24) is connected to the terminal pin (2
6a) and (26b), for example, as shown in FIG.
6b) Form a split groove (28) in the center of the upper end surface, insert the heater wire (21) of this split i1i (28), and connect the cathode (
It is also possible to perform positioning in step 24) and caulk and secure in this state. When the cathode (24) is placed in the first grid (control grid) of the electron gun as described later, the cathode (24) may be slightly shifted in the elongated direction, but it may be shifted in the lateral direction perpendicular to this. This is undesirable because it causes a positional shift between the beam transmission hole of the first grid and the beam transmission hole of the first grid. The configuration shown in FIG. 8 reliably solves this problem. In addition, when fixing by welding, there is a desire that variations in welding resistance often cause variations in resistance (direction) and variations in the current flowing through the heater wire (21).

For this reason, as shown in Fig. 9, the heater wire (21) is pressed against the end surfaces of the terminal pins (26a) and (26b), and the heater wire (21) is connected to an inorganic material (29) such as frit glass. ) and the terminal pins (26a) (26b) can also be fixed together. Furthermore, the terminal pins (26a) and (26b) are not provided, and the 10th
As shown in the figure, a pair of protrusions (30a) and (30b) are integrally provided on a ceramic insulating support (25), and nickel, for example, is sintered on the side surfaces of the protrusions (30a) and (30b). to form a metallized layer (31), electrically connect the heater wire (21) of the cathode (24) in this metallized layer (31), and connect the convex portion (3
0a) and (30b) with inorganic adhesive (3
In step 2), the cathode structure can be constructed by performing mechanical coupling.

The present invention, as shown in FIGS. 11 and 12, incorporates the cathode structure (27) into the first grid, that is, the control grid (G1) constituting the electron gun. ) are arranged with a ceramic spacer (33) in between so that the desired spacing dot is maintained, and the retainer (34)
Fix it with. (G2) is a second grid, that is, an acceleration grating, which is disposed opposite to the first grid (G,) with a ceramic spacer (35) in between. Each grid is arranged like a gun. (hl) and (h2) are the first grid (
G1) and the electron beam transmission hole provided in the second grid (G2).

Next, an example of the dimensions of this electron gun will be shown. As for the cathode (24) (see Figure 4), a tungsten heater! (2
The diameter d of 1) is 10μ, the pitch P of the coil I (22) is 15μ, the diameter d2 of the coil part (22) is 50μ,
The length Sl of the coil R<22> is 0.75 mm, the length S2 of the part to which the oxide (23) is adhered is 1.0 mm, and the diameter d3 of the part to which the oxide (23) is adhered is 60 to 70 μ. . Also, the lead terminal pins (26a) and (26b) in Figure 7
The distance S3 between them is 1.5 mm.

Lead terminal vinyl/ (26a) (26b) diameter d4
is Q, 3mm.

Furthermore, in FIG. 11, the distance d01 between the cathode (24) and the first grid (Gl) is 0. Q5mm, distance d1 between the first grid (G1) and the second grid (G2)
2 is Q, 1 mm, and the diameter d of the beam transmission hole (hl) and (h2).

is 0.2 mm, and the grid plate thickness t is 0.05 mm.
It is.

In the present invention, the cathode (24) is particularly arranged so that the elongated direction of the cathode (24) runs along the perpendicular direction of the phosphor surface on which the phosphor layer is formed.

According to the above-mentioned configuration, when looking at the cathode (24), the base metal is omitted and the heater wire (21) itself is made of oxide (24).
At the same time, it serves as the reducing agent in step 3), and at the same time, the heat capacity of the heater wire (21) itself is very small, and only the necessary part coated with the oxide (23) is wound into a coil shape, resulting in high resistance. , the time required for local heating to reach the temperature required for thermionic emission is extremely short. Furthermore, since the cathode has a very small heat capacity, the power consumption of the cathode is significantly reduced. According to experiments, in the case of the present invention (above example of implementation dimensions), power consumption is -0.0 at Er=0.40V and If=24mA.
096W, whereas in the conventional case shown in Fig. 1, it is E.
f=0.60V.

When I f =300 mA, the power consumption was 0.18 W, and it was confirmed that the cathode power consumption in the present invention was about 1/15 of the conventional power consumption.

In addition, since the oxide-coated part of the heater wire (21) is wound into a coil shape and the resistance value increases, the lead terminal pin (26a)
) and (26b) can now be ignored, and since the coil density does not change when the cathode (24) is heated, the cathode temperature becomes uniform, and the temperature of the thermionic emissive material (23) increases. The phenomenon of peeling off from the heater wire is also prevented, and variations in lifespan are also reduced.

Since the spacing S3 between the lead terminal pins (26a) and (26b) is narrowed to 1.5 mm, the total length of the heater wire is shortened, and the wire portions at both ends are connected to the terminal pins (26a).
and (26b), the cathode (24) can be easily connected to the terminal pins (26a) and (26b).
), the cathode (24) can be securely fixed to the terminal pins (26a) and (26tl), and there is little deformation of the heater wire during installation of the cathode (24) or due to thermal expansion. Cutoff does not change.

In addition, when this cathode (24) draws a current of only about 6 to 7 μA to the fluorescent surface of the cathode ray tube, the working area (36) of the cathode is extremely small as shown in FIG. There is no problem even if the cathode is cylindrical.

In addition, in the past, it took 2.5 to 3.0 seconds for a stable image to appear after turning on the switch, but with the present invention, it takes less than 1 second, for example, 0.1 to 0.2 seconds. A stable image is obtained, and an instantaneous stable image is obtained similarly to the so-called preheat type.

Also, from the perspective of the arrangement of the cathode (24), the spot shape of the electron beam from the cylindrical cathode (24) is basically a circular spot, but the working area is designed to increase the current flow. Even if the spot shape becomes vertically long when expanded, since the cathode (24) is arranged with its longitudinal direction perpendicular to the fluorescent surface as described above, the resolution in the horizontal direction is good. In other words, resolution is usually weaker in the vertical direction than in the horizontal direction, so if the beam is vertically elongated with respect to the screen, the resolution will increase. At the same time, if the beam is vertically long, the raster will not be noticeable.

As described above, according to the present invention, a cathode with low power consumption can be obtained with a simple structure, and accordingly, the power consumption of a cathode ray tube device can be further reduced. By arranging them along the vertical direction, high resolution of the screen can be achieved.

[Brief explanation of the drawing]

FIG. 1 is a plan view showing an example of a conventional cathode structure, FIG. 2 is a side view thereof, FIG. 3 is a sectional view taken along line A-A in FIG. 1, and FIG. 4 is a longitudinal section showing the cathode of the present invention. 5 is a cross-sectional view thereof, and FIG. 6 is a plan view showing an example of the cathode structure of the present invention.
FIG. 7 is a side view thereof, FIGS. 8 and 9 are perspective views showing an example of how to attach the cathode to the lead terminal pin, respectively, and FIG. 10 is a perspective view showing another example of the cathode structure of the present invention. , FIG. 11 is a sectional view of essential parts showing an example of the electron gun of the present invention, FIG. 12 is a sectional view taken from the 90° direction of FIG. 11, and FIG. 13 is a perspective view of a cathode used for explaining the present invention. It is. (21) is the heater wire, (22) is the coiled part, (23)
is a thermionic emitting material, (G1) is a control grid, and (G2) is an acceleration grid. Agent Paige Ito
Hide Matsukuma Mori A-'''! Figure 1 Figure 2 Figure 3 Figure 11 Figure 12 Figure 13 Figure 4 Figure 5 26 Ward◆ Figure 8 Figure 7・i Figure 8 Figure 9 Figure 10

Claims (1)

[Claims] A cathode ray tube device having an electron gun having a linear cathode and a fluorescent surface formed with a phosphor layer, characterized in that the longitudinal direction of the linear cathode is along a direction perpendicular to the fluorescent surface. A cathode ray tube device.