JPH02158040A - Flat plate type display device - Google Patents

Abstract

PURPOSE:To improve the utilizing efficiency of electron beams by providing a plurality of modulating electrodes divided in the longitudinal direction to a plurality of linear cathodes laid at a determined pitch. CONSTITUTION:Electrons generated from a linear cathode is passed through the electron beam passing holes of a face electrode 4 as electron beams 9 by an electric field applied to the face electrode 4 and deflected horizontally by a horizontal deflecting electrode 5, and makes a light emitting part 7 luminous over a determined range to form a picture plane. At this time, the following voltage is applied to a-d of each modulating electrode 2. When the number of electron beams (the number of cathodes) is A, the image insertion time T of an image signal in a horizontal scanning period (1H) is divided to T/A, the time axis of the image signal in the divided individual period is increased A times and extended to T hours, and the resulting signal is applied to each corresponding modulating electrode (for example, 2-a). In the following 1H period, the signal is applied to the electrode 2 in the state where each electron beam is deflected in the vertical direction by a vertical deflecting electrode 6, and after then on, this is repeated.

Description

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

2. Description of the Related Art Recently, thin display devices have been widely used in the field of displaying images, characters, and the like.

An example of these thin display devices is a flat picture tube.

The present applicant previously proposed a flat picture tube in Japanese Patent Laid-Open No. 189848/1989 and Japanese Patent Laid-open No. 193242/1986.

The configuration will be explained below with reference to FIG. In reality, each electrode is built in a glass container, which is a vacuum envelope, but the vacuum envelope is omitted in the figure except for a part to make the internal electrodes clear. Also,
In order to clarify the horizontal and vertical directions of the screen on which images, characters, etc. are displayed, a horizontal direction H and a vertical direction (■) are illustrated on the face plate portion. Vertically long linear cathode 10
A plurality of wire cathodes 101 are arranged independently at equal intervals, and an oxide cathode is formed on the surface of a tungsten wire. The number of linear cathodes 101 and the spacing between them are arbitrary. For example, if the display screen size is 10 inches, the spacing between the linear cathodes 101 is 10 mm, and 20 linear cathodes 101 are arranged vertically at about 160 mm. arranged in length. A face plate portion 102, which is a screen portion separated from the linear cathode 101, and a vertical scanning electrode 103 close to the linear cathode 101 are arranged so as to sandwich the linear cathode 101 therebetween. The vertical scanning electrodes 103 are elongated in the horizontal direction, and are electrically divided and supported on an insulating support 104 at equal pitches. These vertical scanning electrodes 103 are formed as independent electrodes having the same number of horizontal scanning lines in the vertical direction (approximately 480 in the NTSC system) if, for example, a normal television image is to be displayed. Note that the number of vertical scanning electrodes 103 may be 1/n of the number of horizontal scanning lines.

Between the linear cathode 101 and the face plate 102, one grid electrode (
105, second grid electrode (hereinafter referred to as G2 electrode) 106, third grid electrode (hereinafter referred to as G1 electrode) 106, third grid electrode (hereinafter referred to as G2 electrode)
A fourth grid electrode (hereinafter referred to as G4 electrode) 107 and a fourth grid electrode (hereinafter referred to as G4 electrode) 108 are arranged. The number of electrodes is a design matter and is not limited to the number. Each of the electrodes from the G electrode 105 to the G4 electrode 108 has an opening in a portion corresponding to the linear card 101 through which the electron beam passes. The GI electrode 105 is electrically divided into individual linear cathodes 101, and beam modulation for each linear cathode 101 is performed by applying individual electrode video signals. G from G2 electrode 106
The four electrodes 108 are planar electrodes for extracting the electron beam or optimizing the beam diameter in the horizontal and vertical directions. G4 electrode 108
A horizontal deflection electrode 113A is provided between the face plate 102 and the face plate 102.
, 113B, and 113C are arranged symmetrically with respect to the straight axis of the electron beam from each linear cathode 101 and at the same intervals as the linear cathode spacing. Each horizontal deflection electrode 113A
, 113B, and 113C form a conductive film on the surface of the insulating support 114 by plating, vacuum deposition, or the like. Horizontal deflection electrodes 113A, 113B, 113
An optimum DC voltage for optimizing the horizontal spot diameter of each electron beam and a deflection voltage for horizontally deflecting each electron beam are applied to each of the electron beams C. face plate 10
A light emitting layer consisting of a phosphor 115 and a metal back electrode 116 is formed on the inner surface of 2. The phosphor 115 sequentially emits light (R), green (G), and blue (B) in the horizontal direction during color display.
) as stripes or dots.

Next, the operation of the flat picture tube described above will be explained. First, a current is passed through the linear cathode 101 to heat it, and the G
Approximately the same voltage as the linear cathode is applied to one electrode 105 and one vertical scanning electrode (l horizontal scanning lines). At this time, the electron beam advances from the linear cathode 101 toward the G1 electrode 105 and the G2 electrode 106, and the potential of the linear cathode 101 is adjusted so that the electron beam passes through the opening provided in each electrode 105 and 106. Voltage higher than (
100 to 500 cm) is applied to the G2 electrode 106.

Here, the electron beam can be controlled and modulated by applying a potential to the electrode 105 that is more negative than the potential of the linear cathode 101. The electron beam passing through the aperture of the G2 electrode 106 is transferred to the G3 electrode 107 and the G4 electrode 108.
, horizontal deflection type i 113A facing across the electron beam
, 113 B, and 113 C, and a predetermined voltage is applied to these electrodes so that the electron beam diameter becomes a small spot on the fluorescent screen. Here, the horizontal deflection electrode 113A
, 113B, and 113C, individual DC voltages are applied to obtain the best spot diameter, and at the same time, a deflection voltage such as a sawtooth wave, a step wave, or a triangular wave with a horizontal scanning period is simultaneously superimposed, and each electron The beam is horizontally deflected with a predetermined width. The deflected electron beam passes through the phosphor 115
to form a luminescent image on the screen. At this time, in order to obtain a color image, etc., when each electron beam horizontally scans the phosphor 1.15 as described above, each color is applied to the G and electrodes corresponding to the phosphor on which the electron beam is incident. Just apply a modulation signal. Further, vertical scanning in this method is performed by using a vertical scanning electrode 10 provided on the back surface of the linear cathode 101.
3, one horizontal scanning period (I
Only in H), vertical scanning can be performed by applying a potential that generates an electron beam on the phosphor 115 side.

Problems to be Solved by the Invention However, in the above configuration, the efficiency of utilizing the electron beam generated from the linear cathode is poor. That is, the electron beams generated from the linear cathodes 101 arranged in parallel at a predetermined pitch in the horizontal direction are successively switched by the vertical scanning electrodes 103 from the top to the bottom of the screen. Therefore, each electron beam at each intersection of each vertical scanning electrode 103 and the linear cathode 101 moves toward the phosphor 115 side for only one horizontal scanning period in one vertical scanning period, so that the electron beam moves toward the phosphor 115 side. Assuming that the number of scanning lines is approximately 240, each electron beam generated from each of the above-mentioned intersections will occupy 1/24th of the area constituting one screen.
An electron beam is generated toward the phosphor 115 only during the time 0. As the utilization efficiency of these electron beams deteriorates, a large amount of electron beam current is required at each of the above-mentioned intersections, which causes problems such as an increase in the load on the linear cathode and an enlargement of the electron beam spot diameter. Become.

SUMMARY OF THE INVENTION In view of the problems of the conventional devices described above, an object of the present invention is to provide a flat panel display device with high electron beam utilization efficiency.

Means for Solving the Problems In the present invention, at least a plurality of linear cathodes are provided in a vacuum envelope at a predetermined pitch, and each of the linear cathodes is electrically connected to a plurality of electrodes in the length direction thereof. A flat panel display that is provided with divided modulation electrodes, an electrode that deflects an electron beam generated from the intersection of the linear cathode and the modulation electrode with a predetermined width, and a light emitting section that includes a phosphor. It is a device.

Function The present invention uses a vertical scanning electrode provided at the rear of a linear cathode as a modulation electrode that is electrically divided into a plurality of parts for each linear cathode as well as in the length direction of the same linear cathode. A signal for modulating the electron beams is applied simultaneously to the electron beams, and the electron beams are controlled at the same time. After that, each electron beam is deflected horizontally and vertically to cause the phosphors to emit light, and to This constitutes one screen.

In this way, the utilization efficiency of the electron beam current generated from the linear cathode is improved, making it possible to reduce the electron beam current per spot, thereby reducing the load on the linear cathode, and reducing the electron beam current. It is possible to reduce the beam spot diameter.

Embodiments Hereinafter, embodiments of the present invention will be described based on the drawings.

FIG. 1 is an overall perspective view of a flat panel display device according to an embodiment of the present invention.

In FIG. 1, the vacuum envelope 8 is omitted except for a part to make the internal components clear.

1 is an insulating support such as a glass plate, and 2 is a modulation electrode provided on the insulating support l. A plurality of linear cathodes 3 are arranged with a predetermined distance from the modulation electrode 2 and stretched by springs (not shown) at a predetermined pitch. Next, a predetermined distance is maintained from the linear cathode 3 side between the vacuum envelope 8 made of anode glass provided with the light emitting part 7 made of phosphor and the linear cathode 3 described above. A planar electrode 4, a horizontal deflection electrode 5, and a vertical deflection electrode 6 are provided.

An insulating support 1 made of a glass plate or the like is electrically divided at a predetermined pitch in the horizontal (H) direction of the screen in correspondence with the linear cathodes 3, and a plurality of linear cathodes 3 are electrically divided in the length direction of the linear cathodes 3. A modulation electrode 2 is provided which is divided into four parts (in the figure). The modulation electrode 2 may be provided by forming a pattern on the conductive film by mask vapor deposition, screen printing, photoetching, or the like. A linear cathode 3 is arranged opposite to the modulation electrode 2 at a predetermined interval. The linear cathode 3 is a metal wire such as tungsten coated with an oxide cathode, and is stretched at a predetermined pitch in the H direction and in the vertical (V) direction with springs (not shown) at both ends. Deploy. Further, between the linear cathode 3 and a vacuum envelope 8 provided with a light emitting section 7 made of phosphor, an electron beam for passing the electron beam is provided at least at a position facing the linear cathode 2. Each electrode having a passage hole is arranged. Each of these electrodes transmits electrons from the linear cathode 3 to the light emitting section 7 from the linear cathode 3 side.
A planar electrode 4 for drawing out the electron beams to the side, a comb-shaped horizontal electrode 5 horizontally divided into two for deflecting each electron beam simultaneously in the horizontal direction, and a comb-shaped horizontal electrode 5 for deflecting each electron beam simultaneously in the vertical direction. A comb-shaped vertical deflection electrode 6 that is divided into two in the vertical direction is arranged for this purpose. These electrodes are adhered to each other at a portion other than the electron beam passage hole with a predetermined spacing between them, and are arranged so that the positional accuracy of each electrode is maintained.

Next, the operation of this flat panel display device will be explained using FIG. 2.

FIG. 2 shows an electron beam traveling through an electron beam passing hole provided in the planar electrode 4 by an electric field applied to the planar electrode 4, as shown as a vertical line 9 of the flat panel display device shown in FIG. Although not shown, the electron beam 9 is
are deflected horizontally to a predetermined width, and then vertically deflected by a vertical deflection electrode 6, so that each electron beam receives a predetermined range in the horizontal and vertical directions on the light emitting section 7. The light emitting unit 7 is caused to emit light to form - number of screens. At this time, the following voltage is applied to the illumination of each modulation electrode 2. As shown in Fig. 3, if the number of electron beams in the horizontal direction (that is, the number of cathodes) is A, then the video insertion time T of the video signal 10 in a certain horizontal scanning period (IH) is divided into T/A. , the time axis of the video signal of each divided period is multiplied by A and extended to time T, and this signal 11
is applied to each corresponding modulation electrode (in the illustrated case, the 2-A column). In this way, an image over the entire IH is displayed, and during the next IH period, each electron beam is deflected vertically at a predetermined interval by the vertical deflection electrode 6, and the above-mentioned signal is transmitted to the modulation electrode. 2, repeat these operations within the vertical deflection range, and perform these operations simultaneously on the 2- to 2-row columns of the modulation electrodes to form one screen on the light emitting unit 7. can do.

Although the present invention has been described above using examples, the present invention is not limited thereto. The number of divisions of the modulation electrode does not have to be four as shown in FIG.

Further, the signal applied to the modulation signal may be a pulse width modulation signal. Furthermore, the number of electrodes provided between the light emitting section 7 and the linear cathode 3 is not limited, and may be of a configuration other than that of the present invention. Further, although the linear cathode 3 has been described as being stretched in the vertical direction with respect to the screen, there is no problem if it is stretched in the horizontal direction with respect to the screen. Furthermore, if a phosphor consisting of red, green, and blue light emitters is used in the light emitting part 7,
Color display is possible. In addition, although the explanation has been made by providing the modulation electrode 2 behind the linear cathode 3, there is no problem in providing it between the linear cathode 3 and the light emitting section 7, and in that case, the modulation electrode 2 It is sufficient to provide an electron beam passage hole.

Effects of the Invention As described above, according to the present invention, for a plurality of linear cathodes stretched with a predetermined pinch, each of the plurality of linear cathodes is divided at a predetermined pitch in the length direction of the linear cathode. By providing a modulation electrode, it becomes possible to simultaneously control multiple electron beams in the length direction of the linear cathode to cause the phosphor to emit light. The electron beam utilization efficiency in the length direction is improved, and the luminance of light emission is improved accordingly. Furthermore, if the brightness is kept the same, the electron beam current value per spot can be reduced, the spot diameter can be correspondingly reduced, and high resolution can be achieved.

[Brief explanation of the drawing]

FIG. 1 is an overall perspective view of a flat panel display device according to an embodiment of the present invention, FIG. 2 is a sectional view taken in the direction of FIG. FIG. 4, which is a diagram of modulation signals applied to the modulation electrodes in the same embodiment, is an overall perspective view of a conventional flat panel display device. 1...Insulating support body, 2...Modulating electrode,
3... Linear cathode, 4... Planar electrode, 5... Horizontal deflection electrode, 6... Vertical deflection electrode, 7... - Light emitting part, 8... Vacuum envelope. Name of agent: Patent attorney Shigetaka Awano (1 person) / Hakusho (1 person)

Claims (3)

[Claims] (1) At least a plurality of linear cathodes are provided at a predetermined pitch in a vacuum envelope, and a modulation electrode electrically divided into a plurality of parts is provided for each linear cathode in its length direction. A flat panel display device comprising: a deflection electrode that deflects an electron beam generated from the intersection of the linear cathode and the modulation electrode in a predetermined field; and a light emitting section having a phosphor. (2) The flat panel display device according to claim 1, wherein the deflection electrode is an electrode that deflects in both the horizontal and vertical directions. (3) The electron beam generated from the intersection of the linear cathode and the modulation electrode is modulated by each modulation electrode at the same time, and then the light emitting section is caused to emit light all at once. 1) The flat panel display device described above.