JPS613580A - Picture display device - Google Patents

Abstract

PURPOSE:To keep the initial beam orbit at all times to a beam orbit change due to change in the lapse of time by adding a conductive wire detecting the state of an electron beam orbit near both ends of through-holes of a focus electrode. CONSTITUTION:Four conductive wires are added near the upper and lower ends of the through-hole arranged in plurality in the horizontal direction of the vertical focus electrode and outputs of the wires A1, B1, A2 and B2 are sampled by sampling circuits 52-55. The sampled signal is subject to DC level shift by level shift circuits 56-59, A/D-converted by A/D converters 60-63 and stored in an initial memory 64 as an initial value data. Thus data becomes the basic data to be compared with the data in the lapse of time and a vertical deflection signal is changed by reading the data in the alpse of time to a microcomputer 69 and the signal is corrected by applying feedback to the memory 27.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention generates an electron beam for each division when a screen is vertically divided into a plurality of divisions, and generates an electron beam for each division. The present invention relates to a device that displays a plurality of lines by vertically deflecting an electron beam to display a television image as a whole.

Conventional configurations and their problems Traditionally, cathode ray tubes have been mainly used as display elements for displaying color television images, but conventional cathode ray tubes are extremely long and thin compared to the screen size. It was impossible to create a shaped television receiver. In addition, although EL display elements, plasma display devices, liquid crystal display elements, etc. have recently been developed as flat display elements, all of them are insufficient in terms of performance such as brightness, contrast, and color display, and are not suitable for practical use. It has not yet reached the point where it has been standardized.

Therefore, in order to achieve a flat display device using electron beams, the present applicant proposed a new display device in Japanese Patent Application No. 56-20618 (Japanese Unexamined Patent Publication No. 57'-185590). .

This method generates an electron beam for each section when the screen is divided vertically into multiple sections, and deflects each electron beam vertically for each section to create multiple lines. The television image is displayed as a whole.

First, a basic configuration example of the image display confectionery used here will be explained with reference to FIG. This display element includes, from the back to the front, a back electrode (1), a line cathode (2) as a beam source, and a vertical focusing electrode (3) (37').

Vertical deflection electrode (4), beam flow control electrode (5), horizontal focusing electrode (6), horizontal deflection electrode (7), beam acceleration electrode (
8) and a screen plate (9) are arranged to form an M configuration, and these are housed in the evacuated interior of a flat glass bulb (not shown). A line cathode (2) serving as a beam source is stretched horizontally so as to generate an electron beam distributed linearly in the horizontal direction, and a plurality of line cathodes (2) are arranged vertically at appropriate intervals. Book (in the figure (
Only four of them (2a) to (2d) are shown) are provided. In this embodiment, it is assumed that 15 pieces are provided.

Let them be (2a) to (2o).

These wire cathodes (2) are constructed by coating the surface of a tungsten wire with a diameter of 10 to 20 μΦ with an oxide cathode material for thermionic emission. And these line cathodes (2
a) to (2o) are heated so as to generate a thermionic electron beam when a current is passed through them, and as described later, the electron beams are emitted sequentially for a certain period of time starting from the line cathode (2a). controlled by.

The back electrode (1) suppresses the generation of electron beams from other line cathodes other than the line cathode that is controlled to emit electron beams for a certain period of time, and directs the generated electron beams only in the forward direction. It has the effect of pushing out.

This back electrode (1) may be formed by a coating of electrically conductive material applied to the inner surface of the rear wall of the glass bulb.

Moreover, a planar electron beam emitting cathode may be used instead of these back electrodes (υ) and the linear cathode (2).

The vertical focusing electrode (3) is a conductive plate (b) having a horizontally long slit (a) facing each of the line cathodes (2a) to (2o), and it collects the electron beam emitted from the line cathode (2). is taken out through the slit and focused vertically. Electron beams for one horizontal line (86° picture elements) are taken out at the same time. In the figure, only one section in the horizontal direction is shown. slit o
Q may be provided with crosspieces at appropriate intervals in the middle, or may be a row of many through holes arranged at small intervals in the horizontal direction (I!l@ between almost touching). It may be configured substantially as a slit. The vertical focusing electrode (3y is also similar).

A plurality of vertical deflection electrodes (4) are arranged horizontally at intermediate positions between the above-mentioned slits 9/g αq, and conductor axes are provided on the upper and lower surfaces of the insulating substrate (b), respectively. It is made up of the following: Then, a vertical deflection voltage is applied between the opposing conductors o3(2)',
Deflect the electron beam vertically.

In this embodiment, the electron beam from one line shadow @ (2) is deflected vertically to a position corresponding to 16 lines by a pair of conductors UK. and 16 vertical deflection electrodes (4)
1 corresponding to each of the 16 line cathodes (2) by
Five pairs of conductors are constructed and ultimately deflect the electron beam to draw 240 horizontal lines on the screen (9).

Next, the control electrodes (5) are composed of conductive plates (A) each having a long slit a in the vertical direction, and a plurality of them are arranged in parallel in the horizontal direction at a predetermined interval. In the example, 180 conductive plates for control electrodes (15-1) ~
(15-n) is provided. (Only 9 lines are shown in the figure). Each of the control electrodes (5) separates and extracts the electron beam into two picture elements in the horizontal direction, and controls the amount of electron beam passing therethrough in accordance with a video signal for displaying each picture element. Therefore, the conductive plate (1) for the control electrode (5)
If 18080 pieces of 5-1) to (15-n) are installed, horizontal 194
It can display 860 picture elements per 2 minutes. In addition, in order to display images in color, each picture element must be displayed with 8 colors of phosphors: R, G, and H.
RG and B video signals for two picture elements are sequentially added to the . In addition, 180 control type tM (5) conductive plates (15
-1) to (15-n) each has one line worth of
Eighty sets of video signals (two picture elements per set) are applied simultaneously, and one line of video is displayed at one time.

The horizontal focusing electrode (6) is composed of a conductive plate Qη having a plurality of vertically long (up to 180) slits facing opposite to the slit α◆ of the control pole 111c (5), and is divided in the horizontal direction. The electron beams for each picture element are focused horizontally into a narrow electron beam.

The horizontal deflection electrode (7) is composed of a plurality of conductive plates (G) 011 arranged vertically on both sides of the slit αQ, and each electrode (G) has six levels of horizontal deflection. A voltage is applied to horizontally deflect the electron beam for each pixel, and the screen (9)
Above, the two sets of R and QB phosphors are sequentially irradiated to emit light. In this embodiment, the deflection range is two picture elements wide for each electron beam.

The accelerating electrode (8) is composed of a plurality of conductive plates αI arranged horizontally at the same position as the vertical deflection electrode (4), and it screens the electron beam with sufficient energy (
9) Accelerate so that it collides with

The screen (9) has a phosphor gradient coated on the back side of the glass plate (2) that emits light when irradiated with an electron beam, and
A metal back layer (not shown) is added to form the structure. one slit α (on the phosphor) of the control electrode (5)
In other words, two pairs of eight-color phosphors, R, G, and B, are provided for each electron beam divided in the horizontal direction, and are applied in stripes in the vertical direction. There is. The broken lines drawn on the screen (9) in FIG.
5) shows the horizontal divisions displayed corresponding to each of the items.

As shown in the enlarged view in Figure 2, one section partitioned by these two has R, G, and B phosphors for two pixels in the horizontal direction, and 16 lines in the vertical direction. It has a width of The size of one section is, for example, 1 mm in the horizontal direction and 9 mm in the vertical direction.

Note that in FIG. 1] ζ, the length in the horizontal direction is greatly expanded relative to the vertical direction for ease of understanding.

In addition, in this embodiment, one control electrode (5), i.e. one
For the electron beam of the book, the R, G, H phosphors) are 2
Although only one pair for each picture element is provided, it is of course possible to provide one pair for one picture element or more than B picture elements, in which case the control electrode (5) has one pair for one picture element or for three or more picture elements. R, G, and B video signals are sequentially applied, and horizontal deflection is performed in synchronization with the R, G, and B video signals.

Next, the basic configuration and waveforms of each part of a drive circuit for displaying television images on this display element will be explained with reference to FIG. First, a driving portion for irradiating the screen (9) with an electron beam to emit raster light will be described.

The power supply circuit So applies a predetermined bias voltage to each electrode of the display element.
A circuit for applying operating voltage] -■1 to the back electrode (1), Vs to the vertical focusing electrode (3) C3f,
A DC voltage of vs, v6 is applied to the horizontal focusing electrode (6), vs is applied to the acceleration electrode (8), and vs is applied to the screen (9).

Next, a composite video signal of a television signal is applied to the input terminal (), and a vertical synchronizing signal V and a horizontal synchronizing signal +3H are separated and extracted by a synchronizing separation circuit -.

The superposed deflection drive circuit is composed of a vertical deflection counter (2), a memory for storing vertical deflection signals), and a digital-to-analog converter (hereinafter referred to as a DA converter). As input pulses to the superposed deflection drive circuit, a vertical synchronizing signal V and a horizontal synchronizing signal @H shown in FIG. 4 are used. The vertical deflection counter @ (8 bits) is reset by the duplex synchronization signal @V and counts the horizontal synchronization signal H. This severe deflection counter (2) counts the effective scanning period (in this case, a period of 24OH) excluding the vertical retrace period of the vertical period, and this count output is supplied to the address in the memory. Ru. The vertical deflection signal data (in this case, 10 bits) corresponding to each address is output from the memory) and is output to the D-A converter) as shown in Figure 4 (Figure 8 (b).
) is converted into a vertical deflection signal of V, υ′ shown in (D). In this circuit, there are memory addresses for storing vertical deflection signals corresponding to each line for 249H, and 16
By storing regular data in the memory every H minutes, a 16-step vertical deflection signal can be obtained.

On the other hand, the line cathode drive circuit (e) uses the vertical synchronization signal V and the output of the vertical deflection counter (c) to generate the line cathode drive pulse a.
~Create 0. FIG. 5(a) shows the relationship between the vertical synchronizing signal (2), the horizontal synchronizing signal (H), and the lower five bits of the vertical wound counter (2). FIG. 5(b) shows a method of creating line cathode drive pulses a' to 0' every 16H using these signals. In Figure 5, LSB indicates the lowest bit, (
LSB+1) means the bit one higher than the LSB.

The first line cathode drive pulse a' is generated using the vertical synchronizing signal V and the output CLSB+4) of the vertical deflection counter.
The line cathode drive pulses b' to θ' can be generated using a flip-flop or the like, and the line cathode drive pulses a' are output from the vertical deflection counter (2) (L) using a shift register.
This can be achieved by transferring the inverted version of SB +8) as a clock. This drive pulse a'~
0' is inverted and converted into line cathode drive pulses a to 0, which have a low potential only during each pulse period and a high potential of about 20 volts during other periods (Fig. 8(b) E),
It is added to each line cathode (2a) to (2o).

Each line cathode (2a) to (2o) is heated by passing a current during the high potential period of the drive pulses a to 0, and is heated so that electrons can be emitted during the low potential period of the drive pulses a to 0. “state is maintained.” This results in 15 line cathodes (2a
) to (20) respectively generate low potential drive pulses a to
Electrons are emitted only during the 16H period when 0' is added.

During periods when a high potential is applied, the line cathode (2a ) to (20) is more positive, so no electrons are emitted from the line cathodes (2a) to (20).・□Thus, in the line cathode (2), electrons are sequentially emitted from the upper line cathode (2a) to the lower line cathode (2o) for each 16H period during the effective vertical scanning period.

The emitted electrons are pushed forward by the back electrode (υ) and are pushed forward by the opposing slit αQ of the vertical focusing electrode (3).
The beam passes through the beam and is vertically focused into a flat electron beam.

Next, the line cathode drive pulse a% O and the vertical deflection signal 1)
The relationship with mu' will be explained using FIG. The vertical deflection signals t+, t+' are 16 of each line cathode pulse a~0.
During the H period, the IH value changes in 16 steps.

Vertical deflection value? Both iv and V' have a center voltage of V4, and are configured to change in opposite directions so that V increases sequentially and V' decreases sequentially. These vertical deflection values +3v and V' are respectively the vertical deflection electrode (4)
As a result, the electron beams generated from the respective line cathodes (2a) to (2o) are vertically deflected in 16 steps, and as mentioned earlier, the electron beams are applied to the screen (to) and V'. 9) Above, one electron beam is deflected so that a raster of 16 lines is sequentially drawn by 1942 minutes from the top.

As a result of the above, electron beams are emitted for each 16H period starting from the top of the 15 line cathodes (2a) to (2o),
Each electron beam is deflected one line at a time from top to bottom within 15 sections in the vertical direction, so that on the screen (9), from the first line at the top to the second line at the bottom.
The electron beam is vertically deflected one line at a time up to the 40th line, and a total of 240 raster lines are drawn.

The vertically deflected electron beam is sent to the control electrode (5).
It is divided into 180 sections in the horizontal direction by a horizontal focusing electrode (6) and taken out. In Figure 1, one of them
The classification is shown. The passage of this electron beam is controlled for each section by a control electrode (5), and horizontally focused by a horizontal focusing electrode (6) into a single narrow electron beam. The light is deflected in six steps in the direction, and is sequentially irradiated onto each of the R, G, and B phosphors for two picture elements on the screen (9). Second
The figure shows vertical and horizontal divisions. Control electrode (
The phosphors corresponding to (15-1) to (15-n) in 5) are R, G, and B for two picture elements, but for convenience of explanation, one picture element is represented by R1*cl.

Let Bl be R2, G2e and B2.

Next, in terms of the horizontal deflection drive circuit, the horizontal deflection counter @
(11 bits), memory that stores horizontal deflection signals■
, D-A converter). As shown in FIG. 7, input pulses to the horizontal deflection drive circuit are synchronized with the vertical synchronizing signal V and the horizontal synchronizing signal @H, and pulses 6H having a repetition frequency six times that of the horizontal synchronizing signal H are used. The horizontal deflection counter) is reset by the vertical synchronizing signal V and counts the horizontal six times pulse 6H. This horizontal deflection counter) is 6 times during IH, 240H x 6 during 1
/) (=14. Counts 40 times, and this count output is supplied to the address of the memory wire. The memory wire outputs horizontal deflection signal data (here, 8 bits) according to the address, and the D-A , 9 Kankiso, Figure 7 (Figure 8 (
b) Converted to a horizontal deflection signal as shown in C) and h'. This circuit has memory addresses for storing horizontal deflection signals corresponding to each of 6 x 240 lines, and by storing 6 pieces of regular data for each line in the memory, 6 step waves can be generated during the IH period. One horizontal deflection signal can be obtained.

As shown in Fig. 7, this horizontal deflection signal is a pair of horizontal deflection signals and h' that change in 6 steps, both of which have a center voltage of Vy, where h decreases sequentially and h' increases sequentially. They change in opposite directions as they move forward. These horizontal deflection signals h' are applied to electrodes (to) and (to)' of the horizontal deflection electrode (7), respectively. As a result, each horizontally segmented electron beam has a screen (
9) R, G, B, R, Ge B (R1 and Gl.

It is horizontally deflected so that the phosphors of Ble R2# G2 e B2 ) are sequentially irradiated with H/6. Thus, in each line raster, the electron beam is transmitted for each of the 1jllO sections in the horizontal direction such that T<1. Glp Bll R
2, G2s Each phosphor (to) of Bg is sequentially irradiated.

Therefore, the electron beam is R1* for each horizontal section of each line.
A color television image can be displayed on the screen (9) by modulating the video signals of Gl, Bll R11m G21 B2.

Next, the modulation control portion of the electron beam will be explained. First, the composite video signal applied to the television signal input terminal 4 is applied to the color demodulation circuit 2, where the R-
The Y and B-Y color difference signals are demodulated, the G-Y color difference signals are matrix-synthesized, and they are further combined with the luminance signal Y to form the R, G, and B primary color signals @ (hereinafter R, G.
A signal (referred to as a B signal) is output. Those R, G, B
Each video signal is processed by 180 sample and hold circuits (81-
1) to (al-n). Each sample hold circuit (81-1) to (81-n) is for RI and G
It has six sample and hold circuits for I, SBI, sR2, and G2, %B2.

These sample and hold outputs are stored in memory (
82-1) to (82-n).

On the other hand, the reference clock oscillator (to) is composed of a PLL (phase-locked loop) circuit, etc., and in this example, the reference clock 6 fs, which is six times the color subcarrier ho, is used.
c and twice the reference clock 2fBc. The reference clock is controlled to always have a constant phase with respect to the horizontal synchronous signal +jH.

The reference clock 2ch 8c is added to the deflection pulse generating circuit), and a signal 6H, which is six times the horizontal synchronizing signal H, and a daily signal switching pulse r41g1. b1. r21g2. The reference clock 6, fsc, is added to the sampling pulse generation circuit system, where it is input to a shift register and delayed by one clock cycle. , 108 during the effective horizontal scanning period (approximately 50 μsec) of the horizontal period (635 μ5 ec).
0 sampling pulses R11”+I1.BN, R1
2"+21B+2"2+, G2+, B21'R22"G
22"22~R11, Gyll, Bnl, R12"
kll and B12 (FIG. 3(b) A) are generated in sequence, and after that, one transfer pulse t is generated. This sampling pulse RII~Bn2 is one of the images to be displayed.
This corresponds to each picture element when a line is divided into 360 picture elements in the horizontal direction, and its position is controlled so that it is always constant with respect to the horizontal synchronizing signal H.

These iogo sampling pulses RII~Bn
2 are each 180 sets of sample hold times jl&(3
1-1) R1e cll Bl * R1 * Gt s for each 2 picture elements when the image is divided into 180 parts
Each B2 video signal is individually sampled and held. The sample-held 180 pairs R,,G
l, B1. The video signal of R2゜Gl I Bg is 1942
180 sets of memory (82
-1) to (82-n) are transferred all at once by a transfer pulse t, and held here for the next horizontal period. This retained R1゜cl * Bt # R2e cz #
The signals of B, , are sent to the switching circuits (85-1) to (85-1).
5-n). Switching circuit (85-1)
~(85-n) are each R1*clt Bl
It is composed of a tri-state or analog gate having individual input terminals for eRl*c and IB2 and a common output terminal for sequentially switching and outputting them.

The output of each switching circuit (85-1) to (85-n) is 180 sets of pulse width modulation (PWM) circuits (87-1)
~CAT-n), where the sample-held R1. G□e Bl * R2m G2 e B
The reference pulse signal is pulse width modulated according to the magnitude of the two video signals and is output. The repetition period of the reference pulse signal is the above signal switching pulse rx *-g□t 1) x
*re* It is desirable that the pulse width is sufficiently smaller than the gasb2 pulse width, for example, 1:lO~l
: About 100 are used.

The outputs of the pulse width modulation circuits (87-1) to (87-n) are used as control signals for modulating the electron beam to the 180 conductive plates (15-1) to the control electrode (5) of the display element.
(15-n) respectively. Each switching circuit (85-1) to <B5-n) receives a switching pulse 'l o gl m')l*r! applied from the switching pulse generating circuit (to). s gas B2
Switching is controlled at the same time by The switching pulse generating circuit So is the aforementioned deflection pulse generating circuit Uj! - Signal switching pulse r1 m gs * bt e r2 m
It is controlled by gs * bg, and each horizontal period is divided into 6, and each switching circuit (85-1) is divided into H/6.
~(85-n), R1°G1. B1. R2@G
2@B, are time-divided and sequentially output, and a switching signal r1mg1*b1*r2mgz*bw is generated to be supplied to the pulse width modulation circuits (87-1) to (87-n).

What should be noted here is that the switching circuit (85-1
) ~(85-n) R1 m Gl # Bl
m R=Electron beam R1*Gt by IGRe Bjl video signal supply switching and horizontal deflection drive circuit
I Ble R1mG! e The irradiation switching to the phosphor 82 and the horizontal deflection are synchronously controlled so that they completely match both in timing and order. As a result, when the electron beam is irradiating the R1 phosphor, the irradiation amount of the electron beam is controlled by the R1 video signal, and the
(y+, B2 are controlled in the same way, so that each picture element's R1, G1.
, e B2 are controlled by the video signals, and each picture element is displayed by emitting light according to the input video signal. Such control is performed simultaneously for 180 sets of 1 line (2 picture elements each) to display an image of 860 picture elements for 1 line, and is sequentially performed for 240 minutes of lines starting from the upper line to display the screen ( 9) One image will be displayed above.

The above operations are performed on one input television signal.
This is repeated for each field, and as a result, a moving television image is displayed on the screen (9) in the same way as a normal television receiver.

In the above configuration, due to changes in vertical deflection output over time, etc.
The initially set position of the beam changes, and the screen lacks uniformity, making it extremely difficult to see.

Purpose of the Invention The present invention provides an image display device that can maintain the initial high image quality by detecting changes in the beam position over time as described above and always keeping the beam at the initially set beam position. The purpose is to

Components of the Invention The present invention adds conductive wires near both sides of the through-hole of the focusing electrode to detect the state of the electron beam trajectory in such an image display device, and detects the initial state with respect to the beam trajectory displacement due to changes over time. By compensating for this, it is possible to always maintain the initial beam trajectory.

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. 8th
In the figure, <31 (4) indicates the vertical focusing electrode and the vertical deflection electrode as shown in Figure 1, and as shown in Figure 8 (A).
is a view seen from the electron source toward the screen, Figure 8 (B
> is its side view. In the figure, four wires indicated by AI, Bl, 82, and A2 correspond to one electron source, and the upper end of the vertical focusing electrode (3f has a plurality of through holes arranged in a horizontal direction). The conductive wires are placed near the top and bottom edges, and may be installed in pairs of 4 wires for each electron source, or 4 pairs may be installed for each electron source in the entire panel. It may be installed.

FIG. 9 shows the trajectory of the electron beam when viewed from the side. It passes through the range of the solid line when displaying a normal image, and the inner wire B1. It passes inside A2. However, during the blanking period of vertical synchronization, the electron source and vertical deflection signal are adjusted so that the electron source and the vertical deflection signal pass through a trajectory that hits the wires B1 and B2 as shown by broken lines in the figure. Look at this! ! This is shown in Figure 10 (C). In this example, Figure 48(b)
An example is shown in which the eighth electron beam source is turned on as shown in FIG. The beam flow control electrode (6) is signal-modulated to apply a cutoff pulse as shown in FIG. 10(d) so that the phosphor screen does not emit light during the vertical blanking period. And wire AI, Bl and 82. The detection pulse for A2 is the deflection waveform during the blanking period (Fig. 10 (C
This is a pulse signal synchronized with the beginning and end of )), and this is used as a sampling pulse (see Fig. 11). In the initial state, the vertical deflection signal during the blanking period is varied and adjusted so that the wires B1 and B2 are irradiated with the maximum electron beam. The detection output at this time is 11
As shown in FIG. 10(f), the value is shifted in the negative direction from the normal value.

FIG. 11 shows a specific circuit of the embodiment. In FIG. 11, wires AI, Bl, B2 . The output of A2 is sampled by the sampling circuit using a detection pulse, the DC level shift is performed by the level shift circuit, A/D conversion is performed by the A/D converter, and the data is stored in the initial memory. Store it as initial value data. This value becomes the initial value, and is the basic data when comparing with time-lapse data.

The data for the next blanking period are sequentially stored in the detection output memory and compared with the initial value data by the microcomputer. The correlation between this comparative data and the actual electron beam trajectory is shown in FIG. 12 and Table 1.

In Table 1, L means that the data in the detection output memory ~- became lower than the initial value data in the initial value memory, H means that it became higher, [ means that it should not have been lower (
(equal to or higher) respectively.

In the case of Table 1 ■, when the electron beam trajectory i1s1 is physically shifted upward, the detected output data becomes higher as the wire AIJJII child beam approaches, the comparison value becomes L, and the wire A2 The electron beam moves away (thereby, the detection output data does not become high, and the comparison value becomes 1-taL. Also, the comparison value data becomes H for the wires Bl and B!!).

Case (2) is a case where the superposition deflection sensitivity becomes large and the amplitude becomes large.

Case 1 of (2) is the opposite of case (2), and is a case where the electron beam is entirely shifted downward.

Case (2) Contrary to case (2), this is a case where the sensitivity becomes small and the amplitude becomes small.

In the above four cases, a microcomputer is used to change the distortion direct direction signal so that it is in the opposite direction, and feedback is applied to the memory gradient to correct it.

Effects of the Invention According to the present invention, by detecting the vertical deviation of the electron beam (due to changes in the circuit or structure) and feeding it back, the vertical landing bit is always constant and a uniform raster is created. Thus, it is possible to eliminate deterioration over time as an image display device.

[Brief explanation of the drawings] Figure 1 is a structural diagram inside the panel, Figure 2 is a diagram showing unit pixels on the screen surface, Figure 8 is a block diagram of the drive circuit and waveform diagrams of each part, and Figure 4 is a diagram showing the unit pixels on the screen surface. The relationship between the vertical deflection electrode and the synchronization signal, Figure 5 is the timing chart of the counter, and Figure 6 is the timing chart of the counter.
Figure 7 is a relationship diagram of drive output pulses, Figure 7 is a relationship diagram between horizontal deflection signals and synchronization signals, Figure 8 is a structural diagram of main parts showing an embodiment of the present invention, and Figure 9 is an electron beam trajectory diagram. , FIG. 10 is a waveform correlation diagram, FIG. 11 is a circuit diagram of the present invention, and FIG. 12 is an electron beam trajectory diagram corresponding to the table showing feedback logic.

Claims (1)

[Claims] 1. A screen coated with a phosphor that emits light when irradiated with an electron beam; an electron beam source that generates an electron beam for each vertical section of the screen divided into a plurality of vertical sections; a horizontal separating means for separating the electron beam generated by the electron beam source into each of the plurality of horizontal divisions of the screen on the screen and irradiating the electron beam onto the screen; a beam flow control electrode that controls the amount of electron beam irradiated onto the screen to control the amount of light emitted from each pixel on the screen; The device has a focusing electrode that controls the size of light emitted by the electron beam on the phosphor surface and a back electrode that controls the amount of electron beam generated, and detects the state of the electron beam trajectory near both sides of the through hole of the focusing electrode. An image display device that maintains the initial beam trajectory by adding a conductive wire to compensate for changes in the beam trajectory due to changes over time.