JPH0580869B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for driving a video display device such as a color television receiver.

Conventionally, as this type of image display device, a cathode ray tube of a type in which the entire display surface is scanned with an electron beam from a single electron gun is often used. However, this device requires a distance for deflecting the electron beam, and this distance is particularly undesirable in large devices, as this increases the depth of the device. In contrast, a display device is provided for each picture element, and images are displayed by driving each of these display devices according to the level of the portion corresponding to the video signal, but in this case, However, it is necessary to place a display device for each of approximately 300,000 picture elements and perform wiring for each, making the device extremely complex.

In view of these points, the present invention aims to provide a large and thin device with a simple configuration.

That is, in the present invention, a phosphor screen in which red, green, and blue phosphors and black guard bands are arranged parallel to each other and divided vertically and horizontally;
An image display having an electron gun provided facing each of the divided phosphor screens, and vertical deflection means and horizontal deflection means for deflecting the electron beam emitted from the electron gun in vertical and horizontal directions. A method for driving an apparatus, wherein the vertical deflection means and the horizontal deflection means are simultaneously driven over the entire phosphor screen,
Of these, the vertical deflection means is driven stepwise in a horizontal period, stores a video signal for at least one horizontal period, divides the stored video signal in accordance with the horizontal division, and stores the video signal for at least one horizontal period. The divided signals are simultaneously read out, and the read signals are respectively supplied to one row arranged in the horizontal direction within the electron gun. An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a perspective view showing the structure of an apparatus to which the present invention is applied, and FIGS. 2A to 2D are a horizontal sectional view, a vertical sectional view, and a partially removed plan view from the back and front, respectively. Note that these figures show only a portion. In these figures, 1 is a front glass, and this front glass 1 is provided with a phosphor described later. Further, 2 is a back glass. Between the glasses 1 and 2, electron guns and horizontal and vertical deflection means corresponding to the number of divisions of the fluorescent surface, which will be described later, are provided, corresponding to the positions of the divided fluorescent surface parts.

Here, the electron gun includes, from the back glass 2 side, a filament F and a first grid G ₁ for electronic modulation, a second grid G ₂ for an electron gate, and third to fifth grids G ₃ for electrical heating and focusing. Consists of G ₅ .

The first grid _G1 is made of a metal plate that extends in the vertical direction and has a horizontal section bent into a U-shape, and is provided with the opening side facing the back glass 2 side. This first grid G ₁ is arranged at equal intervals equal to the number of horizontal divisions [G ₁₁ , G ₁₂ ...]
be done. A vertically extending filament F is provided inside this first grid _G1 .

Further, the second grid G ₂ is extended horizontally,
It is made of a metal plate whose vertical cross section is bent into a U-shape, and is provided so that the opening side faces the front glass 1 side. This second grid G ₂ is arranged in the vertical direction at equal intervals equal to the number of divisions [G ₂₁ , G ₂₂ . . .]. Holes P 1 and P ₂ are provided at the center of the mutually opposing parts of the intersection of the first and second grids G ₁ and G ₂ , _respectively .
will be provided.

Each of the third to fifth grids G ₃ to _{G 5} is made of a single metal flat plate, and in each of them, at the positions corresponding to the holes P ₁ and P ₂ of the first and second grids G ₁ and G ₂ , Holes P ₃ to _{P 5} each having a predetermined size are provided. These holes P ₃ to _{P 5} are provided on an extension line connecting P ₁ and P ₂ , and when viewed from the front glass 1 side, the filament F is inserted through these holes P ₁ to _{P 5} .
will come to you.

Furthermore, in front of hole _P5 of this fifth grid _G5 ,
A vertical deflection electrode VD is provided. This electrode VD consists of two horizontally extended metal plates V ₁ ,
V ₂ , and these two metal plates V ₁ and V ₂ are provided in a figure-eight shape so as to open toward the front glass 1 side. The number of vertical deflection electrodes VD equal to the number of vertical divisions is provided, each corresponding to the hole _P5 of the fifth grid _G5 .

A horizontal deflection electrode is placed in front of this vertical deflection electrode VD.
HD will be provided. This electrode HD consists of two metal plates H ₁ and H ₂ each extending in the vertical direction, and these two metal plates H ₁ and H ₂ are arranged in a figure-eight shape so that they open toward the front glass 1 side. It will be done. The number of horizontal deflection electrodes HD equal to the number of horizontal divisions is provided, each corresponding to the hole _P5 of the fifth grid _G5 .

Therefore, in this device, the filament F is heated and the first grid _G1 or the filament F is heated.
By supplying a video signal to the second grid G2 and sequentially setting the second grid _G2 to a high potential at predetermined timings, an electron beam modulated by the video signal is generated in each period. This electron beam is accelerated and focused by the third to fifth grids _G3 to _G5 , deflected by deflection electrodes VD and HD, and projected onto a fluorescent surface provided on the front glass 1.

These electron guns and horizontal and vertical deflection means are arranged in a matrix, for example, 64 sets in the horizontal direction and 30 sets in the vertical direction, for a total of 1920 sets.

If the device shown in this figure is configured as a 40-inch video display device, the electron guns will be installed at a pitch of 1.25 cm horizontally and 2.0 cm vertically, and the overall width will be 80 cm and the height will be 80 cm. It can be configured with a length of 60cm and a depth of 7cm.

Furthermore, in this device, the video signal, the voltage of the second grid, and the horizontal and vertical deflection voltages are supplied as follows.

In FIG. 3, for example, an NTSC color television signal received and demodulated by the tuner 11 is a luminance signal,
Separation circuit 1 for chroma signal and horizontal and vertical synchronization signals
The separated luminance signal and chroma signal are supplied to the matrix circuit 13, and the three primary color signals of red, green, and blue are taken out. These three primary color signals are, for example, CCD14R, 14 of 630 stages.
G, 14B.

Further, a synchronizing signal from the separation circuit 12 is supplied to a pulse generation circuit 15 to form various timing pulses. In this generation circuit 15,
A clock pulse P _C having a timing obtained by dividing the video portion of one horizontal period by 640 is generated, and this clock pulse P _C is supplied to the clock terminals of the CCDs 14R, 14G, and 14B.

Furthermore, these CCD14R, 14G, 14B
Intermediate output terminals are derived from the respective input terminals and positions of every 10 stages from the input side, and these output terminals are combined with those from the same stage positions, and these are connected to three-input changeover switches 16 ₁ and 16 , respectively. ₂ ...16 ₆₄ is supplied.

In addition, a switching signal P _K having a frequency three times that of the clock pulse P _C is generated in the pulse generating circuit 15.
This switching signal _PK is supplied to the switches 16 ₁ to 16 ₆₄ , and the signals from the CCDs 14R, 14G, and 14B are sequentially taken out in a time-division manner.

Signals from these switches 16 ₁ to 16 ₆₄ are transmitted to CCDs 17 ₁ , 17 ₂ . . . 17 of 30 stages, respectively.
₆₄ supplied.

Furthermore, a high frequency clock pulse P _C ' having the same frequency as the switching signal P _K from the generation circuit 15 is applied to the CCD 17 ₁ to
The signals from the switches 16 ₁ to _{16 64 are} written to the CCDs 17 ₁ to 17 ₆₄ . Furthermore, a low frequency clock pulse _P''C with a frequency of 1/63 of the switching signal _PK from the generation circuit 15 is applied to the CCDs ₁₇₁ to 17.
The signals supplied to CCD ₆₄ and written to CCDs 17 ₁ to 17 ₆₄ are read out. The timing of writing and reading is such that, for example, for a video signal of one horizontal period as shown in FIG. 4A, writing is performed in the latter 1/64th period of the video portion as shown in FIG. 4B. 63/6 of the first half of the video part of the next horizontal period
Reading is performed during period 4 (see FIG. 4C).

The signals read from these CCDs _{17 1} to 17 ₆₄ are respectively transmitted to the first grids G ₁₁ , G ₁₂ . . .
…Supplied to G ₁₆₄ .

Furthermore, in the generation circuit 15, a video period of one vertical period (480 horizontal periods) is generated in synchronization with the horizontal synchronization signal.
A timing pulse Pt is formed by dividing the portion into 30, and this timing pulse is supplied to the 30-decimal counter 18. The gate pulse signals from each output terminal of this counter 18 are sent to the second grid.
G ₂₁ , G ₂₂ ...supplied to G ₂₃₀ .

Further, the horizontal synchronizing signal (see FIG. 5A) from the generation circuit 15 is supplied to the horizontal deflection circuit 19 to form sawtooth horizontal deflection signals as shown in FIG. 5B and C. is the horizontal deflection electrode H ₁ ,
Supplied with _H2 . Furthermore, the timing pulse Pt (see FIG. 6A) from the generation circuit 15 is supplied to the vertical deflection circuit 20 to form a sawtooth vertical deflection signal as shown in FIGS. 6B and C, and the horizontal deflection circuit Horizontal deflection signals as shown in FIG. 6 D and E from 19 are supplied to the vertical deflection circuit 20, and these signals are combined and change stepwise with horizontal synchronization as shown in FIG. 6 F and G. Vertical deflection signals are formed and these vertical deflection signals are connected to the vertical deflection electrodes V ₁ ,
Supplied to V ₂ . Further, the high voltage HV generated by the horizontal deflection circuit 19 is supplied to the third and fifth grids G ₃ and G ₅ , the holding and shielding plates Sp, Sq, and S _R , and the fluorescent surface.

Furthermore, in this device, the fluorescent surface is constructed as follows.

FIG. 7 shows a partially cutaway perspective view. In the figure, inside the front glass 1 are red P _R , green P _G , blue P _B
Three colored phosphors are arranged repeatedly in a vertical stripe pattern, and a black guard band _G is provided between each phosphor, and a blue phosphor _P and a red phosphor are arranged repeatedly in a vertical stripe pattern. The width of the guard zone G′ _u between the body P _R is the same as that of the other guard zone
Such a guard band G′ _u is made larger than the width of G _u
640 sets of three-color phosphor stripes P _R , P _G , P _B sandwiched between stripes are provided horizontally over substantially the entire surface of the front glass 1 .

This phosphor surface is divided into 10 sets of phosphor stripes, and each divided portion is arranged so that its center line faces each hole _P5 of the electron gun shown in FIG.

Furthermore, a partition plate S _p extending in the vertical direction is provided between the guard band G' _u corresponding to the boundary of every 10 sets of phosphor stripes and the horizontal deflection electrodes H ₁ and H ₂ (see Fig. 1).
will be provided.

Therefore, in this device, CCD17 ₁ to 17 ₆₄
Electron beams are emitted in response to signals from the phosphor, which are deflected horizontally and vertically and displayed on each divided portion of the fluorescent surface. and in this case
The CCDs 17 ₁ to 17 ₆₄ output signals corresponding to the fluorescent surface portions obtained by dividing the signal of the horizontal period, and these are processed simultaneously by each electron gun arranged in the horizontal direction, resulting in a unified signal as a whole. A horizontal scan line of the book is displayed. This is then vertically scanned, and when the vertical scanning with one electron gun is completed,
The next vertical stage electron gun is gated on,
This scanning is performed sequentially in the vertical direction to reproduce the received video signal.

The video signal received in this way is reproduced.According to the present invention, each electron gun is in charge of a narrow range of the divided fluorescent surface portion, so that the vertical and The horizontal deflection angle is small, the distance required for deflection is small, and the overall device depth is reduced.

In addition, the number of wiring lines is 64 video signal lines connected to the first grid _G1 , 30 signal lines from the counter 18 connected to the second grid _G2 , vertical deflection signal lines, horizontal deflection signal lines, Only a small number of around 100 high-voltage lines etc. are required, making the configuration extremely simple.

Furthermore, since a large number of electron guns are integrally formed, the structure is extremely simple and manufacturing is easy. This is especially true for the third to fifth grids _G3 to _G5 .
It is extremely easy to do this because all you have to do is drill holes _P3 to _P5 at desired positions on the metal plate.

Furthermore, since the vertical deflection signal is changed in a stepwise manner, the vertical positions of the starting and ending ends of horizontal scanning in each fluorescent surface portion are equal, and the horizontal scanning line is displayed on a single straight line. Therefore, horizontal seams are not noticeable and a good image can be obtained.

Furthermore, since the distance from the electron gun to the fluorescent surface is short, the spread of the diameter of the electron beam is small, making it possible to obtain a good image with high sharpness.

In addition, the horizontal scanning speed of each electron beam becomes 1/64, and the amount of beam irradiated to each phosphor increases by 64 times, so the amount of emitted electron beam may be reduced to 1/64. As a result, the electron beam can be made even narrower.

As described above, since the electron beam is thin and the scanning speed is slow, the electron beam can be landed on the phosphor very accurately. Therefore, without using conventional beam selection means such as a shadow mask, the beam modulation signal can be switched sequentially to red, green, and blue in time with the phosphor reaching it.
Three-color display can be performed using a so-called dot sequential method. This increases the irradiation efficiency of the electron beam, so the amount of emitted beam can be further reduced.
It is also possible to narrow the electron beam.

Furthermore, the overall shape of this device may be a shape in which two front portions of cathode ray tubes are glued together as shown in FIG. 8A, or one in which one is flat as shown in FIG. 8B. Furthermore, as shown in FIG. 8C, two flat plates may be arranged in parallel and sealed with other surrounding members. In the case of the shape C, since there is a risk that the center of the flat plate may be dented by external pressure, a part of the partition plate SP (see FIG. 1) may be made into a rigid body and supported as a support. The above-described device is enclosed in such a case.

In addition, each grid G ₁ ~ G ₅ and vertical and horizontal deflection electrodes
V ₁ , V ₂ , H ₁ , H _{2 ,} etc. may be formed integrally over the entire device, but may be divided as necessary for manufacturing reasons. This is because there is a risk that the position of the hole _P5 will shift due to thermal expansion, especially in a place like the fifth grid _G5 , which is irradiated with a large amount _of electron beams. to reduce the effect of thermal expansion.

Furthermore, as shown in Figure 1, each grid
Supports ST are provided at key points of G ₁ to _{G 5} to increase the rigidity of the device and to prevent the holes P ₁ to _{P 5} from shifting.

Furthermore, the vertical deflection electrodes V ₁ and V ₂ are not limited to the arrangement of two metal plates in a figure-eight shape as described above;
You can use a bent metal plate as shown in Figure 9B, combine two bent metal plates punched into an E-shape as shown in Figure 9B, or combine two bent metal plates as shown in Figure 9C. A large number of metal plates provided with holes of a predetermined size may be laminated. In the examples shown in these figures, the potential relationship between adjacent vertical deflection electrodes is reversed. Therefore, in every other vertical deflection, the deflection signal is reversely changed, and as a whole, the vertical deflection is performed using a deflection signal that changes in a triangular manner as shown in FIGS. 6H and 6J.

Further, FIG. 10 shows a specific example of the horizontal deflection electrodes H ₁ and H ₂ . Figure 10A uses two metal plates; the side facing the fluorescent surface of the metal plate is widened to form a figure eight shape, and one side of each electrode is connected with a conductive wire. be done. FIG. 10B shows a combination of two bent metal plates punched into a U-shape, and a conductive wire is connected to each metal plate. In FIG. 10C, a large number of metal plates each having a hole of a predetermined size are laminated, and every other metal plate is connected to each other, and a conductive wire is connected to each metal plate.

Further, FIG. 11 shows a filament drive circuit in the case where a video signal is directly supplied to the filament. In the figure, 30 is an input terminal to which a signal from, for example, a CCD ₁₇₁ is supplied, and this terminal 30 is connected to the base of a pnp type transistor 33 through transistors 31 and 32.
3 collector is grounded. Also transistor 3
2 is in the opposite direction through the diode 34 ₁ ...34 _o
connected to the base of the npn transistor 35;
The collector of this transistor 35 is the power supply terminal 36
connected to. A filament F ₁ is connected between the emitters of transistors 33 and 35.

Therefore, in this circuit, a constant voltage determined by the diodes 34 ₁ to 34 _o is supplied across the filament F ₁ , and the overall potential is changed in accordance with the signal supplied to the input terminal 30 .

This circuit is provided between each of the CCDs 17 ₁ to 17 ₆₄ and the filaments F ₁ to F ₆₄ , respectively.

In this way, a constant voltage for heating and a video signal are supplied to each filament.

Furthermore, in this device, since an electron gun and vertical and horizontal deflection means are provided for each fluorescent surface portion, display can be performed without using the entire surface if necessary. In other words, for example, if the screen aspect ratio is 1:
It is also possible to form a display device having a configuration of 2:2 and display an image using only the portion with an aspect ratio of 3:4. In this case, to switch from 1:2 to 3:4, no signal is supplied to the filament F and the first grid _G1 , which do not perform display.

Furthermore, the supply of video signals and vertical and horizontal deflection may be performed separately for each fluorescent surface portion.
In that case, each fluorescent surface section can be used as an independent display device, so it can be used as a so-called picture display.
Various special effects such as in-picture can be performed.

It is also easy to convert the number of horizontal scanning lines, for example from the Japanese-American standard system (525 lines) to the European standard system (625 lines), and further increase the precision to 1125 lines.

Thus, according to the present invention, it is possible to form and drive a large and thin video display device with an extremely simple configuration.

[Brief explanation of the drawing]

Fig. 1 is a perspective view of the essential parts of an example of a device to which the present invention is applied, Fig. 2 is a plan view seen from all sides, Fig. 3 is a block diagram of the signal system, and Figs. 4 to 11 are It is a figure for explanation. 1 is a front glass, 2 is a back glass, G ₁ to _{G 5} are grids, F is a filament, and VD and HD are deflection electrodes.

Claims (1)

[Claims] 1 Red, green, and blue phosphors and black guard bands are arranged parallel to each other, and a phosphor screen is divided vertically and horizontally, and an electron beam is provided opposite each of the divided phosphors. A method for driving an image display device having a gun, and vertical deflection means and horizontal deflection means for deflecting an electron beam emitted from the electron gun in vertical and horizontal directions, the method comprising: a vertical deflection means and a horizontal deflection means; The vertical deflection means is driven simultaneously over the entire phosphor screen, and the vertical deflection means is driven stepwise in a horizontal period, and stores a video signal for at least one horizontal period, and stores the video signal for at least one horizontal period. It is characterized in that the divided signals are divided corresponding to the horizontal division, the divided signals are simultaneously read out, and the read signals are respectively supplied to one row arranged in the horizontal direction in the electron gun. A method of driving a video display device.