JPS60189848A - Plate-type cathode-ray tube - Google Patents

Abstract

PURPOSE:To improve the diameter of electron beam spots and reduce the deflection electric power synthesizing an image picture while causing the phosphor of the inner surface of a face plate and given areas of the luminous layer of a metal back layer to emit light in order by means of electron beams. CONSTITUTION:On the back surface of one or several linear hot cathodes 10 divided horizontally to the image screen, vertical scanning electrodes 12 are installed the number of which is at least the number of horizontal scanning lines. Then, vertically homogeneous electron beams produced by heating the linear hot cathodes 10 are turned on and off in order to scan the image screen from its top to the bottom. The electron beam produced from each linear hot cathode 10 is modulated by an image signal before a horizontal deflection is given to the modulated electron beam to cause a phosphor layer to emit light thereby synthesizing an image picture. As a result, the horizontal diameters of spots located at the same level become the same, thereby improviing the diameter of electron beam spots and reducing the deflection electric power.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a flat cathode ray tube used in color television receivers, computer terminal displays, and the like.

Conventional Structure and its Problems Conventionally, as a flat cathode ray tube, a structure as shown in FIG. 1 has been described in Japanese Unexamined Patent Publication No. 46-2619. That is, a fluorescent surface 2 is formed on the inner surface of the vacuum envelope 1, and a plurality of vertical deflection electrodes 3 which are elongated in the horizontal direction and divided by a predetermined pinch in the vertical direction are arranged parallel to and opposite to the fluorescent surface 2. The electron gun is elongated in the horizontal direction in the vertical scanning extension direction of the fluorescent surface 2, and has an electron gun for producing individual electron beams. The method of operation of a flat cathode ray tube having these structures is that thermionic electrons generated by heating the electron source 4 are extracted as electron beams 8 through openings provided in the grid electrode 5, and then individually beamed by the grid electrode 6. Modulation is performed on each beam. The modulation method is performed by electrically dividing individual apertures and applying individual beam modulation voltages to each electrode.

Next, each modulated electron beam passes through the aperture of the shield electrode 7, and then passes between the fluorescent surface 2 and the vertical deflection electrode 3 provided opposite the fluorescent surface 2, for example. Surface 2 and the vertical deflection plate go straight at the same potential (VD), then V
At the vertical deflection electrode to which a potential (V'o-cc) lower than D is applied, the electron beam is deflected toward the phosphor surface 2 under the influence of the electric field, causing the phosphor to emit light.

By sequentially performing these deflection operations on each of the vertical deflection electrodes, vertical scanning of the electron beam 8 can be performed, and a normal television image can be displayed on the fluorescent surface 2 by these operations.

However, in this flat cathode ray tube, the electron gun that generates the electron beam must generate electron beams corresponding to each picture element in the horizontal direction, and one picture element of a normal television image is Since the color pitch is about 0.1 to 0.2M, it is a big electrical and mechanical problem to generate an electron beam at these pitches and to individually modulate the electron beam. Even if these are possible, it is still necessary to keep the spot diameter of the electron beam and the accuracy of the incident position on the phosphor surface 2 constant for each beam in the electron beam traveling section from the electron gun section to the phosphor section. It is extremely difficult to do so. In addition, since the vertical deflection electrode 3 switches from the same potential as the fluorescent surface 2 to the potential at which it is not deflected, the switching operation is performed at a high voltage, and the deflection power is also quite large. Although flat cathode ray tubes have the advantage of being simple in structure, they have many problems in terms of performance and the like.

OBJECTS OF THE INVENTION The present invention relates to a new flat cathode ray tube that solves the problems of the flat cathode ray tube described above, and improves the electron beam spot diameter, reduces the deflection power, and improves the accuracy of the electron beam traveling position. The purpose is to improve the

Structure of the Invention The present invention provides vertical scanning divided electrodes for switching electron beams in the vertical direction within a vacuum envelope, which are elongated in the vertical direction of the screen, and are arranged in parallel at a predetermined pitch in the horizontal direction. Corresponding to these linear hot cathodes, there are a plurality of electrically divided modulation electrodes, a horizontal focusing electrode for obtaining horizontal beam focus, and a horizontal focusing electrode for horizontally deflecting the electron beam. It is composed of at least a light emitting section consisting of a plurality of horizontal deflection electrodes and a fluorescent material.

Description of examples Hereinafter, the present invention will be explained using examples.

Fig. 2 shows the structure of a flat cathode ray tube according to the first embodiment of the present invention.Actually, each electrode is housed in a vacuum envelope (glass container), but in the figure In order to make the internal electrodes clear, the vacuum envelope is omitted. However, a portion of the face portion that becomes the vacuum envelope is shown. Further, in order to clarify the horizontal and vertical directions of the screen on which nine characters, etc. are displayed, the horizontal direction (H) and vertical direction (V) are illustrated on the face plate portion. First, a plurality of linear hot cathodes 10 each having an oxide cathode formed on the surface of a tungsten wire are arranged independently at equal intervals in the horizontal direction, and are placed under appropriate tension in the vertical direction. The number of linear hot cathodes 1Q and the spacing between them are a design matter. For example, if the display area is 10 inches, the horizontal spacing between the linear hot cathodes 1Q and 20 lines in the horizontal direction is approximately 1o. The hot cathode 1o is approximately 160m vertically.
It is arranged with a length of . On the opposite side of the face plate 9 with the linear hot cathode 10 in between, there is an insulating support 11 that is equally pinched in the vertical direction (V) and electrically divided in close proximity to the linear hot cathode 1°. An elongated vertical scanning electrode 12 is arranged in the horizontal direction (H).

Since these vertical scanning electrodes 12 display normal TV images, they are formed as 490 independent electrodes in the vertical direction. Next, the linear hot cathode 1o and the face plate 9
Between the linear hot cathode 1 and the linear hot cathode 1
A planar first grid electrode 13 in which an aperture for focusing and accelerating the electron beam is formed is arranged in a portion corresponding to 0, and then an electric electrode is provided corresponding to each linear hot cathode 1o. A second modulating grid electrode 14 which is physically independent and has an electron beam passage hole is disposed, and a third grid electrode 15 having the same shape as the first grid electrode 13 is further disposed. Next, a horizontal deflection electrode 16 for applying a horizontal direction (H) deflection to the electron beam passing through the electron beam passing hole provided in each electrode 13, 14° 16 is inserted into the aperture of each electrode. The electron beam is placed opposite to the electron beam passing through the section and is electrically independent. Here, the horizontal deflection electrode 16 is provided with electrically independent metal films on both surfaces of a base such as an insulating support. Next, a layer 17 that emits light upon stimulation of an electron beam is formed on the inner surface of the faceplate 9 with a phosphor and a metal bank layer. When displaying black and white, it is sufficient to use one layer of phosphor, but when displaying power 2, the phosphors are sequentially arranged in the horizontal direction (H), such as grandson and green.

Formed as blue stripes or dots.

Next, let's look at how these flat cathode ray tubes operate.
This will be explained using FIG. FIG. 3 is a horizontal cross-sectional structural diagram of the flat plate type @ polar ray tube of the present invention shown in FIG. 2. The electrons generated by heating the linear hot cathode 1o are heated by the electric field applied to the vertical scanning electrode 12 provided on the back surface of the linear hot cathode 10 and the first grid electrode 13. The electron beam passes through the electron beam passage hole of the first grid electrode 13 provided opposite to the electron beam 10. In the figure, although the electron beam cannot actually be seen directly, the electron beam trajectory is indicated by 18 for ease of understanding. 1st
The electron beam that has passed through the opening of the grid electrode 13 is modulated (for example, ON/OFF operation) by the second modulation grid electrode 14 that is electrically divided corresponding to the linear hot cathode 1o. will be carried out. In fact, as described later, if used for color display, red, green, blue, red,
green.

The sequential modulation signals designated as blue... are applied. A modulation signal is applied to the electron beam generated by each linear hot cathode 1o, and a third grid electrode 15 having the same shape as the first grid electrode 13 provides a shielding effect and horizontal focusing. next,
A horizontal deflection electrode 16 is provided for each linear hot cathode 10 so as to face the electron beam, and a sawtooth or stepped horizontal deflection voltage is applied to the horizontal deflection electrode 16 through wirings 161 and 162. Each electron beam is horizontally deflected by a predetermined width. Each horizontally deflected electron beam is then electrically accelerated and stimulates the light emitting layer 17 formed on the vacuum inner surface of the face plate 9 to emit light. At this time, if you try to display color on the screen,
As mentioned above, each electron beam is horizontally deflected,
At a predetermined position for each color, the second modulation grid electrode 1
By applying a modulation signal corresponding to each color to 4, a color display image can be displayed.

Here, it has been described that the electron beam 18 generated from the linear hot cathode 1o is applied with a modulation signal, and is focused and deflected in the horizontal direction to cause a predetermined phosphor 1 to emit light. Also, it is necessary to switch the electron beam corresponding to the scanning line. As shown in FIG. 4, the method for switching the electron beam in the vertical direction is as shown in FIG. The image is electrically divided into 490 horizontal scanning line segments in the vertical direction (V) and arranged. The electrode may be formed by forming a conductive material such as a metal film or an oxide film on the insulator 11 using a method such as photoetching. May be processed. Next, a vertical scanning signal is applied to each of the divided vertical scanning electrodes 12 one by one. The applied signal gives ON/OFF operation to the electron beam generated from the linear hot cathode 10, and in the first field, the electron beam is turned ON only in the 1H section from the terminal 12A. signal, terminal 12C
A signal that turns on the electron beam only in the next 1H period is sequentially applied to every other vertical scanning electrode, and a signal that turns on the electron beam in the 1H period is applied to every other vertical scanning electrode. Then, when a signal is applied to the terminal 12X at the bottom of the screen and the scan ends, the first one field scan ends, and then the interlace operation starts and the vertical scan of the second field starts. In the second field, a signal is similarly applied from the terminal 12B to turn on the electron beam for only the 1H period every other field, and the electron beam is finally scanned to the lowest terminal 12Y, completing one frame operation.

As described above, a plurality of linear hot cathodes 10 are arranged in a vacuum container horizontally with respect to the screen, and the linear hot cathodes 10
A number of vertical scanning electrodes 12 corresponding to the number of horizontal scanning lines are disposed on the back surface of the linear hot cathode 10, perpendicular to the linear hot cathode 10, and the number of vertical scanning electrodes 12 corresponding to the horizontal scanning lines is A vertically uniform electron beam generated by heating the hot cathode 10 is sequentially turned ON and OFF, and these electron beams are transferred to individually divided modulation electrodes provided corresponding to the linear hot cathode 10. 14, the electron beam is modulated, and then focused and deflected in the horizontal direction, causing predetermined positions of the phosphor layer 17 to sequentially emit light, thereby displaying one image character etc. synthesized on the screen. The present invention provides a novel flat-plate cathode ray tube.

Next, a second embodiment of the present invention will be described using FIG. 6. FIG. 6 shows the structure of a flat cathode ray tube as in the first embodiment, and the vacuum envelope is omitted except for a part of the face. First, in order to clarify the direction of the display screen, the horizontal direction (H) and vertical direction (V) of the screen are clearly indicated on the face plate 18, which is a part of the vacuum envelope.

As for the internal structure, vertical scanning electrodes 2o for switching the electron beam in the vertical direction are electrically divided into the number of scanning lines in the vertical direction of the screen on an insulating support 19 starting from the rearmost part of the screen. Placed. The vertical scanning electrode 20 is a metal film, an oxide film, or the like made of a conductive material, and is formed by a photoetching method, a mask vapor deposition method, a screen printing method, or the like. Next, a plurality of linear hot cathodes 21 are arranged at predetermined intervals in the horizontal direction perpendicular to the vertical scanning electrodes 20 and at predetermined intervals from the vertical scanning electrodes 20. next,
A planar first grid electrode 22 having an electron beam passage hole and a similar second grid electrode 23 are arranged at a position facing the linear hot cathode 21 at a predetermined interval. Next, the horizontal deflection electrodes 24 are electrically divided and placed facing each other so as to sandwich the electron beam passage hole of the second grid electrode 23. Next, on the inner surface of the face plate 18,
A light-emitting layer 25 consisting of a phosphor and a metal back layer that emits light when stimulated by an electron beam is formed. The operating method of such a flat cathode ray tube is as shown in FIG.
7, the cathode is heated to about 700°C and brought into a state where it emits electrons. However, in reality, the counter electrode (first grid electrode 22) for extracting the electron beam
Since a negative voltage is applied to the cathode, the electron beam cannot pass through the beam passage hole of the counter electrode. A pulse generation modulation circuit 281 is connected to each linear hot cathode.
282 by applying a negative pulse voltage greater than the voltage of the opposing first grid electrode 22.
The grid electrode 22 becomes positive with respect to the cathode, an electron current flows, and an electron beam proportional to the pulse voltage can be obtained. At this time, the diodes 291 and 292 are in the opposite direction. Current no longer flows through the linear hot cathodes 211 and 212, and the potential difference between the two ends of each of the linear hot cathodes 211 and 212 becomes almost zero. Therefore, the linear hot cathodes The parts 211 and 212 have the same potential, and a uniform electron current can be obtained within the cathode. Here, as a pulse to be applied to the linear hot cathodes 211, 212, a pulse width modulation signal modulated by a video signal or the like is added, and for example, as shown in the opening of FIG. 6, the linear hot cathodes 211, 212 are heated. Sudame DC voltage and
If used for color display, red and green during one horizontal scanning period.

By adding blue, sequentially pulse width modulated signals, electron streams modulated with each video signal can be obtained.

Next, returning to FIG. 5, the electron beam generated by being modulated by the linear hot cathode 21 is transmitted through a vertical scanning beam provided close to the back surface of the linear hot cathode 21, as in the first embodiment. Electrode 2o
As a result, a pulse signal is applied to the vertically uniform electron beam generated by the linear hot cathode 21 so as to perform vertical scanning. Next, the electron beam generated from the linear hot cathode 21 is transmitted to the first grid electrode 22 and the second grid electrode.
Horizontal focusing is performed by the grid electrode 23 and the like, and horizontal deflection is performed by the horizontal deflection electrode 24. After acceleration, a predetermined position of the light emitting layer 26 formed on the inner surface of the face plate 18 is scanned. , combine them into one image. Here, of course, if the light-emitting layer 25 is a oak screen consisting of red, green, and blue phosphor stripes,
The electron beam is horizontally deflected to determine the position corresponding to each color,
Needless to say, the pulse width modulation signals applied to the linear hot cathode 21 must be matched.

As described above, in the second embodiment, each linear hot cathode 2
By applying a modulation signal such as an image to the linear hot cathode 21 for the electron beam generated from the electron beam, the modulation electrode provided corresponding to the linear hot cathode 21 explained in the first embodiment is omitted. Next, the configuration shown in FIG. 7 will be described as a third embodiment. In FIG. 7, 30 is a linear hot cathode, and 31 is a vertical scanning electrode formed on an insulating support 32. In FIG. Reference numeral 33 denotes a first grid electrode for extracting the electron beam, and a light emitting layer 36 made of a fluorescent material is formed on the inner surface of the face plate 34, and the light emitting layer 36 is connected to the first grid electrode 33 as in the first and second embodiments. An electrode for horizontally focusing the electron beam, a horizontal deflection electrode, etc. are actually inserted between the layer 35, but these are omitted in FIG. Next, these operations will be explained. First, an electron beam generated by heating the linear hot cathode 3o advances to the light-emitting layer 35 as an electron beam due to the potential given by the first grid electrode 33 and the vertical scanning electrode 31. At this time, as described above, a pulse signal is applied to the vertical scanning electrode 31 to turn on and off the electron beam so that scanning is performed sequentially from the top to the bottom of the screen.

In the first and second embodiments described above, it has been explained that scan electrodes of the current TV system are arranged, but here, % of -246 vertical scan electrodes are arranged.

Next, for example, if seven electron beams are now being generated at positions corresponding to ■2 in order, the first field is the vertical scanning electrodes of vl and V3, which are before and after the vertical scanning electrode of v2. By setting the potential relationship vl>■3 to the scanning electrode, the electron beam of 72 parts is slightly deflected to the side {1} as shown by the solid line 36a, causing the light emitting layer 36 to emit light. Next, in the second field, by setting the potential relationship vl<v3, the light emitting layer 36 is slightly deflected to the v3 side as shown by a dotted line 360, contrary to the first field, and causes the light emitting layer 36 to emit light. As described above, by performing these operations for each vertical scanning electrode, interlace operation of the 1st field and 2nd field becomes possible, and since the number of vertical scanning electrodes can be reduced to %, wiring is easy. Furthermore, it has the advantage of reducing the number of circuit components.

Next, a fourth embodiment of the present invention will be described using FIG. 8. Similar to FIG. 7, FIG. 8 is a side view of a flat cathode ray tube, with some electrodes other than those of the present invention being omitted. Vertical deflection plates 401 and 402 for vertically deflecting the electron beam are inserted between the linear hot cathode 39 and the face plate 42 serving as a vacuum envelope. The vertical scanning electrodes 38 disposed close to the insulating support 37 are electrically divided and installed in the vertical direction of the screen corresponding to the number of ends of the horizontal scanning lines. Vertical deflection electrode 40
1.402 is 2 for the vertical scanning electrode 38, respectively.
These two electrodes are made of planar metal and have crosspieces in the vertical direction at twice the pitch, and the two electrodes are arranged so that the crosspieces are out of phase by 180° in the vertical direction. Next, to explain how these configurations operate, vertically uniform electrons generated by heating the linear hot cathode 39 are transferred to a vertical The scanning electrode 38 applies a potential to generate an electron beam for only one horizontal scanning period, and the electron beam is sequentially switched (scanned) in the vertical direction using this potential. For example, although not shown, an electron beam 43B corresponding to the vertical scanning electrode 38B (which cannot be seen directly) is extracted to the face plate 42 side by a beam extraction electrode, and then is directed to the vertical deflection electrode 401. By .402, the most
The first field is slightly deflected in the vertical direction of the screen.

This deflection method can be carried out by creating a difference in the potential relationship applied to each electrode. For example, the voltage applied to each electrode is V2O3''40
2, the electron beam is bent toward the V4O2 side by setting V4O1>V4O2.

Next, the second field reverses these potential relationships (V4O
1〈■4゜2), the electron beam is bent toward the V4O1 side as shown by the dotted line. By these methods, the electron beams of the first field and the second field are
Each provides interlaced operation, allowing normal television scanning. Here, the same effect can be obtained by arranging vertical scanning electrodes 401 and 402 divided into two electrodes in a method using two electrodes in the electron beam traveling direction. In addition, the vertical deflection electrode is one piece, and it is configured to have crosspieces at the same pitch as the vertical scanning electrode,
This vertical scanning electrode is arranged with its center off-center, and even if the potential applied to this electrode is changed, the electron beam can be deflected in the vertical direction.

As described above, according to this method, since the vertical scanning electrodes 38 can be made % of the number of horizontal scanning lines, the number of connections with circuits and the number of circuit parts can be reduced, and power and cost can be reduced.

The present invention has been described above using examples, but the number of grid electrodes, the number of linear hot cathodes, the position of each electrode, etc. are design matters. For example, the horizontal deflection electrode is a plate-shaped electrode. Alternatively, it may be located between the first grid electrode and the second grid electrode.

Moreover, the number of linear hot cathodes may be one. In addition, the electron beam passing holes provided in each grid electrode may be in the form of a complete slit, and the holes L+11.1, which fit the vertical scanning electrodes,
Suntoha I! ! Note that the embodiments shown in FIGS. 7 and 8 have independent modulation electrodes as shown in FIG. 2, as well as independent modulation electrodes as shown in FIG. It can also be applied to a device in which modulation is performed by applying a modulation signal to a linear hot cathode.

Effects of the Invention The present invention provides a method in which a plurality of linear hot cathodes divided in the horizontal direction are arranged for one or a screen, and vertical scanning electrodes are arranged in the vertical direction on the back of the hot cathodes, corresponding to at least the horizontal scanning lines. death,
1. Supports vertical scanning with a vertically uniform electron beam generated by heating a linear hot cathode. ON, O
The FF is operated to scan from the bottom of the screen, and after modulating the electron beams emitted from each linear hot cathode with an image signal, it is deflected in the horizontal direction to cause the phosphor layer to emit light. , which is synthesized as a single image on a screen, and since a planar grid electrode with an opening for the electron beam and a horizontal deflection electrode are arranged corresponding to the linear hot cathode, the electron beam in the horizontal direction is The beam spot diameter becomes the same in the vertical direction of the screen, improving uniformity and improving color purity, color unevenness, etc.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing an example of a conventional flat cathode ray tube, FIG. 2 is a perspective view showing the structure of a flat cathode ray tube showing a first embodiment of the present invention, and FIG. 3 is the configuration of FIG. cross-sectional view, 4th
5 is a perspective view showing the structure of a flat cathode ray tube according to a second embodiment of the present invention; and FIG. 5 is a circuit diagram and a waveform Φ diagram showing the operation of the configuration shown in FIG. 5, FIG. 10.21.30.39... linear hot cathode, 11°19.32.37...・Insulating support, 12, 20° 31.38... Vertical scanning electrode, 13, 22.33
...First grid electrode, 14...Modulation grid electrode, 15.23...Third grid electrode,
16.24...Horizontal deflection electrode, 17,25,3
5.41...Light emitting layer, 27...Continuous power supply,
211,212... Line hot cathode, 281.28
2...Pulse generation modulation circuit, 29j, 292.
...Diode, 4o1゜402...Vertical deflection electrode. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Figure 3------ゝ9 Figure 4 lf t2g +---j i-------[-1 (2v -----------] L-++ −(
h tey ++ −−−−−−−−−−−−−−−−−：
L---Figure 5 Figure 6

Claims (1)

[Scope of Claims] (1) A single hot cathode or a plurality of linear hot cathodes that are independent in the horizontal direction and elongated in the vertical direction are disposed in the vacuum envelope so as to extend vertically parallel to the screen; On the back side of the linear hot cathode, electrically divided vertical scanning electrodes, the number of which corresponds to the number of horizontal scanning lines, are arranged perpendicular to the linear hot cathode, and vertical scanning electrodes are arranged across the linear hot cathode. On the opposite side, a planar grid electrode having an electron beam passing hole at a position facing the linear hot cathode, and electrodes for horizontally deflecting individual electron beams are arranged. A flat cathode ray tube characterized in that predetermined positions of a light emitting layer consisting of a phosphor formed on a metal back layer and a phosphor layer are made to sequentially emit light using an electron beam, and the emitted light is synthesized into a single image on a screen. (2) A method according to claim 1, which has a plurality of planar grid electrodes, and has an electron beam modulation electrode electrically independently arranged between the grid electrodes corresponding to the linear hot cathode. Flat cathode ray tube. (3) The light emitting layer formed on the inner surface of the face plate is
Consists of phosphor stripes or dots that emit red, green, and blue light.A horizontal deflection electrode deflects the electron beam in the horizontal direction to cause each phosphor to emit light, and also modulates the electron beam in accordance with each emitted color. 3. The flat cathode ray tube according to claim 2, wherein electron beam modulation signals of each color are applied to the electrodes. (4) A patent claim characterized in that a DC voltage for heating and a modulation signal whose pulse width is modulated by a video signal are sequentially applied to the linear hot cathode, and an electron beam corresponding to the modulation signal is extracted. A flat cathode ray tube according to item 1. (6) The vertical scanning electrodes are individually set at a potential such that the electron beams generated by heating the linear hot cathode are sequentially emitted toward the phosphor for one horizontal period in the vertical direction of the screen. 4. A flat cathode ray tube according to claim 1, wherein a voltage is applied to a vertical scanning electrode to perform frame scanning using an electron beam. (6) Set the number of divisions of vertical scanning electrodes as a percentage of horizontal scanning lines,
In the first field, a pulse signal that generates an electron beam for one horizontal period is applied to the n-th vertical scanning electrode, and the potential applied to the (nl )-th and (nl )-th vertical scanning electrodes is
(n+1)〉v(n-1), and in the next second field, the potential relationship is expressed as v(n+1)〈”(n-1).
By doing so, the electron beam generated by the n-th vertical scanning electrode is interlaced in the first field and the second field, and these operations are performed sequentially for each vertical scanning electrode. A flat cathode ray tube according to any one of claims 1 and 3. (7) For vertical scanning electrodes, the number of divisions is % of the horizontal scanning line.
It has a vertical deflection means for vertically deflecting each electron beam between the linear hot cathode and the face plate, and performs an interlace operation in the first field scan and the second field scan. A flat cathode ray tube according to any one of claims 1 and 3, characterized in that: