JPS60246182A - Picture display device - Google Patents

Abstract

PURPOSE:To attain double density effect by changing a vertical focus independently of horizontal focus so as to apply loose vertical focus at non-interlacing and bury the space between horizontal lines in a pseudo way. CONSTITUTION:A vertical deflection signal is fed to the base of a transistor (Tr) Tr1 and a Tr2 amplifies the said signal. In order to change the vertical focus at interlacing and non-interlacing, a switch 50 is connected to a bias terminal B of the Tr2 and the switch 50 and resistors r8, r9, r10 change the bias voltage. When the vertical deflection signal VN+,N- in waveform diagram is a waveform at normal focusing (at interlacing), a mean value VFN of both signals is a focus voltage, and it is changed into a focus voltage VFN, as a waveform shown in broken lines at a non-interlacing so as not to change the deflection sensitivity of the signals VN+', VN-' while keeping the voltage difference of both the signals. Thus, the space between the horizontal lines is buried in a pseudo way at the non-interlacing.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention generates an electron beam for each division when a screen on a screen is vertically divided into a plurality of divisions, and generates an electron beam for each division. The present invention relates to an apparatus for displaying a plurality of lines by vertically deflecting a 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 have not been put into practical use. It has not yet been reached.

Therefore, in order to achieve a flat display device using electron beams, the present applicant filed Japanese Patent Application No. 56-20618 (
A novel display device was proposed in Japanese Patent Application Laid-Open No. 57-135590.

This method generates an electron beam for each section when the screen is vertically divided into multiple sections, and deflects each electron beam vertically for each section to generate multiple lines of radiation. , and displays a television image as a whole. First, a basic configuration example of an image display element used here will be described with reference to FIG. 1.

This display element includes, in order from the back to the front, a back electrode 1, a line cathode 2 as a beam source, and vertical focusing electrodes 3, 3'.
, a vertical deflection electrode 4, a beam flow control electrode 6, a horizontal focusing electrode 6, a horizontal deflection electrode T, a beam acceleration electrode 8, and a screen plate 9 are arranged, and these are made of flat glass pulp (not shown). The interior is housed in a vacuum.

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 (here, (Only four wires, 2i to 22 are shown) are provided. In this embodiment, it is assumed that 16 pieces are provided. Let's call them 2i~2yo. 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.

These line cathodes 2A to 2Y are heated so as to generate a thermionic electron beam by passing an electric current through them, and as will be described later, the electron beams are generated sequentially for a certain period of time starting from the line cathode 2I. controlled to emit. The back electrode 1 suppresses generation of electron beams from line cathodes 2 other than the line cathode 2 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 film of a conductive material adhered to the inner surface of the rear wall of the glass pulp. Further, instead of the back electrode 1 and the linear cathode 2, a planar electron beam emitting cathode may be used.

The vertical focusing electrode 3 is a conductive plate 11 having a horizontally long slit 1o facing each of the line cathodes 2i to 2yo, and takes out the electron beam emitted from the line cathode 2 through the slit 10, and vertically focus in a direction.

Electron beams for one horizontal line (360 pixels) are taken out at the same time.

In the figure, only one section in the horizontal direction is shown. The slit 1o may be provided with crosspieces at appropriate intervals in the middle, or it may be a row of through holes arranged horizontally at small intervals (intervals such that the slits almost touch each other). It may also be configured as a slit. The vertical focusing electrode 3' is also similar.

A plurality of vertical deflection electrodes 4 are arranged horizontally at intermediate positions of the slits 10, and conductors 13, 13' are provided on the upper and lower surfaces of the insulating substrate 12, respectively.
It consists of a set of A vertical deflection voltage is applied between the opposing conductors 13 and 13' to deflect the electron beam in the vertical direction. In this embodiment, one wire cathode 2 is formed by a pair of conductors 13 and 13'.
A blank electron beam is vertically deflected to a position corresponding to 16 lines.

The 16 vertical deflection electrodes 4 constitute 15 pairs of conductors corresponding to each of the 16 line cathodes 2, and the electron beams are deflected to draw 240 horizontal lines on the screen 9. do.

Next, the control electrodes 5 are composed of conductive plates 16 each having a vertically long slit 14, and a plurality of control electrodes 16 are arranged in parallel in the horizontal direction at predetermined intervals. In this embodiment, 180 conductive plates 15a to 16n for control electrodes are provided (only nine are shown in the figure). Each of the control electrodes 6 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 plates 15a to 15n for the control electrode 6 are
If 0 lines are provided, 360 picture elements can be displayed per horizontal line. In order to display images in color, each picture element is displayed with phosphors of three colors, R, G, and B, and each control electrode 5 has two picture elements of R, G, and B. Each video signal is added sequentially.

In addition, 180 sets of video signals for one rhino (one set has two pixels) are simultaneously applied to each of the 180 conductive plates 15a to 15n for the control electrode 5, and the video for one line is displayed at one time. Ru.

The horizontal focusing electrode 6 has a plurality of vertically long slits 1 (100 slits) facing the nozzle 14 of the control electrode 5.
The electron beam is composed of a conductive plate 17 having a conductive plate 17 having a conductive plate 17, and focuses electron beams for each picture element divided horizontally into a narrow electron beam.

The horizontal deflection electrode 7 is the same as above! J) A plurality of conductive plates 18 are arranged vertically on both sides of each of the conductive plates 18.
, 18', each electrode 18.18
A six-step horizontal deflection voltage is applied to the screen 9 to deflect the electron beam of each picture element in the horizontal direction.
Above, the two sets of R, G, and B phosphors are sequentially irradiated to emit light.

In this embodiment, the deflection range is two picture elements wide for each electron beam.

The acceleration electrode 8 is composed of a plurality of conductive plates 19 provided horizontally at the same position as the vertical deflection electrode 4.
The electron beam is accelerated to collide with the screen 9 with sufficient energy.

The screen 9 is constructed by applying a phosphor 20 that emits light when irradiated with an electron beam to the back surface of a glass plate 21, and adding a metal bank layer (not shown).

The phosphors 20 are provided with two pairs of phosphors of three colors, R2G and B, for each slit 14 of the control electrode 6, that is, for each horizontally divided electron beam. It is applied in vertical stripes.

In FIG. 1, the broken lines drawn on the screen 9 indicate divisions in the vertical direction that are displayed corresponding to each of the plurality of line cathodes 2, and the two-dot chain lines correspond to each of the plurality of control electrodes 6. Indicates the horizontal division displayed. As shown in the enlarged view in Fig. 2, one section partitioned by these two has two R, G, and B phosphors for two picture elements in the horizontal direction.
It has a width of 16 lines in the vertical direction.

The size of one section is, for example, 1 h in the horizontal direction and 9 h in the vertical direction.

Note that in FIG. 1, the length in the horizontal direction is greatly enlarged relative to the length in the vertical direction for clarity.

Furthermore, in this embodiment, only one pair of R, G, and H phosphors 2o are provided for one control electrode 5, that is, one electron beam, for two picture elements, but of course, one picture element The control electrode 5 may be provided with R, G, B for one picture element or three picture elements or more.
Video signals are applied sequentially, and horizontal deflection is performed in synchronization with the video signals.

Next, the basic configuration 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 22 is a circuit for applying a predetermined bias voltage (operating voltage) to each electrode of the display element. A DC voltage of v6 is applied to the horizontal focusing electrode 6, a DC voltage of 18 is applied to the accelerating electrode 8, and a DC voltage of v9 is applied to the screen 9.

Next, a composite video signal of a television signal is applied to the input terminal 23, and a synchronization separation circuit 24 separates and extracts a vertical synchronization signal V and a horizontal synchronization signal H.

The vertical deflection drive circuit 40 has a vertical deflection counter=25,
It is composed of a memory 27 for storing vertical deflection signals and a digital-to-analog converter 39 (hereinafter referred to as a DA converter). The input pulse of the vertical deflection drive circuit 40 is as follows:
A vertical synchronization signal V and a horizontal synchronization signal H shown in FIG. 4 are used. The vertical deflection counter 25 (8 bits) is reset by the vertical synchronizing signal V and counts the horizontal synchronizing signal H. This vertical deflection force raster 26 is calculated during an effective scanning period (in this case, 24
This count output is supplied to the address of the memory 27. The memory 27 outputs vertical deflection signal data (here, 10 bits) corresponding to each address, and the DA converter 39 outputs the data of the vertical deflection signal as shown in FIG.

V' is converted into a vertical deflection signal. In this circuit, 24O
There is a memory address for storing a vertical deflection signal corresponding to each line of H minutes, and by storing regular data in the memory every 1 eH minutes, 16 levels of vertical deflection signals can be obtained.

On the other hand, the line cathode drive circuit 26 uses the vertical synchronization signal V and the output of the vertical deflection counter 26 to create line cathode drive pulses [I to YO]. FIG. 5(a) shows the vertical synchronizing signal V, the horizontal synchronizing signal H, and the lower five of the vertical deflection counter 26.
Indicates focus relationship. FIG. 6(b) shows a method of creating line cathode drive pulses [A' to Y'] every 16H using these signals. In FIG. 6, LSB indicates the lowest bit, and (LSB+1) means the bit one higher than the LSB.

The first line cathode drive pulse [A'] can be created using an R-S flip-flop or the like using the vertical synchronization signal V and the output (LSB+4) of the vertical deflection counter 25. ' to Y'] can be obtained by using a shift register to transfer the line cathode drive pulse [A'] using the inverted version of the output (LSB+3) of the vertical deflection counter 25 as a clock. This drive pulse [A' to Yo'] is inverted and converted into a line cathode drive pulse [I to Yo], which has a low potential only during each pulse period and a high potential of about 20 volts during other periods, It is added to each line cathode 2-2.

Each line cathode 2i to 2yo is heated by a current flowing through it during the high potential of the driving pulse [i to yo].
The heated state is maintained so that electrons can be emitted during the low potential period of 1 to 2. As a result, 15 wire cathodes 2
From Y to Y, electrons are emitted only during the 1eH period when a low potential drive pulse [I to Y] is applied to each of them. During the period when a high potential is applied, the back electrode 1 and the vertical focusing electrode 3
Since the high potential applied to the linear cathodes 2i to 2yo is more positive than the potential at the position of the linear cathodes 2 determined by the bias voltage applied to the linear cathodes 2i to 2yo, No electrons are emitted from yo. Thus, in the line cathode 2, electrons are sequentially emitted from the upper line cathode 2a toward the lower line cathode 2y every 16H period during the effective vertical scanning period.

The emitted electrons are pushed forward by the back electrode 1, pass through the opposing slits 10 of the vertical focusing electrode 3, and are vertically focused to form a flat electron beam.

Next, the line cathode drive pulses [I to Y] and the vertical deflection signal v
, v' will be explained using FIG.

The vertical deflection signals v and v' are each line cathode pulse [I to Y]
During the 16H period, it changes by 1H and changes in 16 steps. The center voltage of both vertical deflection signals V and V' is v4.
They are trapped so that they change in opposite directions, such that ■ increases sequentially and V' decreases sequentially. These vertical deflection signals V and V' are applied to the electrodes 13 and 13' of the vertical deflection electrode 4, respectively, and as a result, the electron beams generated from the respective line cathodes 2I to 2Y are deflected in 16 steps in the vertical direction. As described above, one electron beam is deflected on the screen 9 so that a raster of 16 lines is sequentially drawn from the top at a rate of 1 line/minute.

As a result of the above, electron beams are emitted for each 16H period from the top of the 16 line cathodes 2I to 2Y, and each electron beam is sequentially emitted for one line from top to bottom within 15 sections in the vertical direction. As a result, the electron beam is vertically deflected one line at a time on the screen 9 from the first line at the top end to the 240th line at the bottom end, thereby drawing a raster of 240 lines in total.

The electron beam thus vertically deflected is horizontally divided into 180 sections by the control electrode 5 and the horizontal focusing electrode 6 and extracted. Figure 1 shows one of these categories. The amount of passage of this electron beam is controlled for each section by a control electrode 5, and is focused horizontally by a horizontal focusing electrode 6 into a single thin electron beam.
The light is deflected in six steps in the horizontal direction by the horizontal deflection means described below, and is sequentially irradiated onto the R, G, and B light bodies 20 corresponding to two picture elements on the screen 9. FIG. 2 shows the vertical and horizontal divisions. Control electrodes 6 15a to 15, respectively
The phosphors corresponding to n are R, G, and B for two picture elements, but for convenience of explanation, one picture element is R1°G1. B1 and the other R2
, G2. Let's call it B2.

Next, the horizontal deflection drive circuit 41 is composed of a horizontal deflection counter (11 bits), a memory 29 storing a horizontal deflection signal, and a DA converter 38. As shown in FIG. 7, the input pulses of the horizontal deflection drive circuit 41 are synchronized with the vertical synchronizing signal V and the horizontal synchronizing signal H, and a pulse 6H having a repetition frequency six times that of the horizontal synchronizing signal H is used.

The horizontal deflection counter 28 is reset by the vertical synchronizing signal V and counts the horizontal six-fold pulse 6H. This horizontal deflection counter 28 counts 6 times during 1H and 240H×6/H=1440 times during 1V, and this count output is supplied to the address of the memory 29. From the memory 29, horizontal deflection signal data (
Here, 8 bits) are output, and the D-A converter 38 outputs the
It is converted into horizontal deflection signals such as h and h' shown in FIG.

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 are generated in 1H period. A horizontal deflection signal can be obtained.

As shown in Figure 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 7, where h decreases sequentially and h' increases sequentially. As they progress, they change in opposite directions. These horizontal deflection signals h' are applied to horizontal deflection electrodes 18 and 18', respectively. As a result, each horizontally divided electron beam is transmitted to the R, G, B, R of the screen 9 during each horizontal period.
, G, B (R1, G1.B1.R2, G2. B2) are horizontally deflected so that the phosphors are sequentially irradiated with H/e. Thus, in the raster of each line, the electron beams are divided into R1, G1, . B1.
Each phosphor 2o of R2, G2°B2 is sequentially irradiated with light.

Therefore, the electron beam is set to R1, G for each horizontal section of each line.
1. B1. R2, G2. By modulating the B2 video signal, a color television image can be displayed on the screen 9.

Next, the modulation control portion of the electron beam will be explained.

First, the composite video signal applied to the television signal input terminal 23 is applied to the color demodulation circuit 3o, where the R-Y
and B-Y color difference signals are demodulated, the G-Y color difference signals are matrix-synthesized, and further, they are combined with the luminance signal Y to generate R, G, and H primary color signals (hereinafter R, G, and B (referred to as a video signal) is output. These R, G, and B video signals are processed by 180 sample and hold circuit sets 31a to 31.
There will be an error in addition to n. Each sample and hold circuit set 31a to 3
1n is for R1, G1, B1, R2, G2 respectively
for.

It has six sample and hold circuits for B2. Those sample and hold outputs are each held by memory set 3.
Added to 2a-32H.

On the other hand, the reference clock oscillator 33 is constituted by a PLL (phase locked loop) circuit, etc., and in this embodiment, the reference clock 6fsc is six times as large as the color subcarrier fsc.
and generates a reference clock 2f8C twice as large. The reference clock is controlled to always have a constant phase with respect to the horizontal synchronizing signal H. The reference clock 2fso is added to the deflection pulse generation circuit 42, and the horizontal synchronizing signal H 6
Double signal 6H and - every signal switching pulse r1. (1,
, bl, r2, q2゜q2. I am getting a B2 pulse. On the other hand, the reference clock 6f8C is applied to the sampling pulse generation circuit 34, where it is delayed by one clock period by a shift register, etc., so that the horizontal period (
The effective horizontal scanning period (approximately 50
1000 sampling pulses Ra1~
Bn2 are generated sequentially, and then one transfer pulse t is generated. This sampling pulse Ra1~Bn2
corresponds to each picture element when one line of the video to be displayed is divided into 360 picture elements in the horizontal direction, and its position is controlled to always be constant with respect to the horizontal synchronizing signal H.

These 1080 sampling pulses Ra1 to Bn2
are each 180 sample and hold circuit sets 31a~
31n, and thereby R1, G1 . B
1. R2, G2. Each B2 video signal is individually sampled and held.

The sample-held 180 pairs of R,,G1゜B
1. R2, G2. After the B2 video signal is sampled and held for one line, 180 sets of memo IJ 32 a~
32n, the signals are transferred all at once by a transfer pulse t, and held here for the next horizontal period. This retained R1.
G1. B, , R2, G2. The B2 signal is applied to switching circuits 35a-35n. The switching circuits 35 a to 35 n each have R1, G1 . B1
．． R2°G2. It is composed of a tri-state or analog gate having individual input terminals of B2 and a common output terminal that sequentially switches and outputs them.

The output of each switching circuit 35a-35n is applied to 180 sets of pulse width modulation (PWM) circuits 376-37n,
Here, the sample-held R1. G1. B1. R
2, G2. The reference pulse signal is pulse width modulated according to the magnitude of the B2 video signal and output. The repetition period of the reference pulse signal is the above signal switching pulse, Xr1+9
1 + b1 + "2192. It is desirable that the pulse width is sufficiently smaller than the pulse width of R2. For example, 1:10
~1:100 is used.

The outputs of the pulse width modulation circuits 3a to 37n are individually applied to the 180 single electric plates 15a to 15n of the control electrode 6 of the display element as control signals for modulating the electron beam. Each of the switching circuits 35a to 35n receives a switching pulse r1゜ql + bl + r2 +q2 + applied from the switching pulse generating circuit 3e.
Switching is controlled simultaneously by b2.

The switching pulse generation circuit 36 receives the signal switching pulse r1+91+b1 from the deflection pulse generation circuit 42 described above.
+r21q2+b2, each horizontal period is divided into 6, and each H/e switching circuit 35a
~35n, R1, G1 . B1. R2, G2゜B
The switching signal r1 is configured to time-divide and sequentially output each video signal of 2 and supply it to the pulse width modulation circuits 37a-37n
+q1 +b1 +r2+b2+92 is generated.

What should be noted here is that the switching circuit 35 a
-R1 at 35n. G11B1. R2, G2. B2
The horizontal deflection drive circuit 41 switches the supply of electron beams R1, G1 . B, , R2, G2. The horizontal deflection for switching the irradiation to the phosphor B2 is synchronously controlled so that it completely matches both the timing and the 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 G1. B, ,R2
, G2. B2 is similarly controlled, and R1, G, , B1 . R2, G2. B2 The light emission of each party light is caused by the R1, G1 . B1. R2, G2. Each picture element is controlled by the B2 video signal, and each picture element is displayed by emitting light according to the input video signal.

Such control is performed simultaneously for 180 sets of one line (2 picture elements each) to display an image of 360 picture elements for one line, and then sequentially for 240 minutes of lines starting from the upper line. One image will be displayed.

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.

By the way, as shown in FIGS. 8a and 8b, in a normal television signal, the vertical direction (VN) of the first field and the second field are
In the vertical deflection (VN') of the field, the horizontal lines are aligned vertically so as to be intercalated with each other. That is, between the horizontal lines H1, H2, ... R16 of the first field, the horizontal lines r, H2r, ... of the second field are formed.
...R16' starts scanning.

However, in signal equipment such as personal computers that do not have binary brightness changes (HIGH and LOW) and do not interlace, the horizontal lines H1 to H16
and the horizontal line H16' match, the number of horizontal lines becomes % of the normal number, and the screen becomes coarse in the vertical direction.

OBJECTS OF THE INVENTION The present invention aims to eliminate the above-mentioned drawbacks, and it is an object of the present invention to provide an image display device capable of producing a double-density effect using a non-interlaced signal generating device such as a personal computer.

Structure of the Invention Since the image display device according to the present invention can change the vertical focus independently of the horizontal focus, only the vertical focus voltage can be changed when receiving an interlace synchronization signal and when receiving a non-interlace synchronization signal.
When non-interlaced, the vertical focus is softened to pseudo-fill the space between each horizontal line to create a double-density effect.

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. 9 and 10. Figure 9 is an example of a circuit for changing the vertical focusing voltage applied to the vertical focusing electrode, and in the figure Tr1 is the base terminal A.
Tt2 is a transistor for amplifying the vertical deflection signal, r11'i is a collector load resistance, r2 is an emitter resistance, and Tr3 to Tr7 are
and r3 to r7 are transistors and resistors that constitute a low impedance output circuit. resistance r and resistance r6
The blade terminal C is pulled out from the connection point.

In the above configuration, a constant bias voltage is normally applied to the bias terminal EK of the transistor T r 2, which determines the DC level of its collector output. In order to change with time, a switch 6o is connected to the bias terminal B, and a bias resistor r81r91"10 is connected in series and inserted between the bias terminal B and the connecting point of the resistors r8 and r9 of the series circuit of 10. r9 and resistance r1
The fixed terminals of the switches 6o are each drawn out from the connection point of .degree., and the bias voltage value is changed by switching the switch 5o. Although Fig. 9 shows only one vertical deflection signal (V or v7 in Fig. 4), the voltage difference between the two vertical deflection signals is also adjusted so that the voltage difference between the two vertical deflection signals does not change. Switch.

In FIG. 1o, the vertical deflection signal vN+ is a solid line.

If vN- is the waveform during normal focus (interlaced), the average value vFN of both signals vN+ and ■N- is the focus voltage, and when it is non-interlaced, the vertical deflection signal vN+ is the waveform shown by the broken line. ' and vN-'
The difference voltage between both signals is set to 1 to avoid changing the deflection sensitivity of
Change the focus voltage with the switch so that it becomes low like ■FN'. As a result, when non-interlacing is performed, the space between each horizontal line is filled in a pseudo manner to produce a double density effect.

Effects of the Invention As described above, according to the present invention, by changing the vertical focus voltage between interlaced and non-interlaced times, and making the vertical focus softer during non-interlaced times, the scanning position of the electron beam does not change, but the pseudo It is possible to create a double-density effect and obtain an easy-to-read screen.

[Brief explanation of the drawing]

FIG. 1 is an exploded perspective view of an image display element used in an image display device according to an embodiment of the present invention, FIG. 2 is an enlarged view of the fluorescent surface of the image display element, and FIG. A block diagram of a drive circuit devised prior to the present invention for driving, FIG. 4, FIG. 6, FIG. 6, and FIG. 7 are waveform diagrams of various parts for explaining the operation of the drive circuit, respectively. Figure 8 is gear number 4, a diagram to explain the interlacing operation,
FIG. 9 is a circuit diagram of a main part of an image display device according to an embodiment of the present invention, and FIG. 10 is a waveform diagram for explaining the operation of the device. 2.2i~2yo...line cathode, 3,3'...
・Vertical focusing electrode, 4... Vertical deflection electrode, 5...
... Beam flow control electrode, 7 ... Horizontal deflection electrode, 9 ... Screen plate, 1o ... Slit, 2o ... Fluorescent material, 23 ... ...Input terminal, 24...Synchronization separation circuit, 26...Vertical deflection counter, 26...Line cathode drive circuit, 2.
... Memory, 28 ... Horizontal deflection counter, 29 ... Memory, 30 ... Color demodulation circuit, 31a to 31n ... Sample hold circuit,
32a to 32n...Memory, 33...Reference clock oscillator, 34...Sampling pulse generation circuit, 35a to 35n...Switching circuit, 36
...Switching pulse generation circuit, 37a to 37n.
...PWM circuit, 38 ...D/A converter, 3
9...D/A converter, 4o...Vertical deflection drive circuit, 41...Horizontal deflection drive circuit, 42...
・Deflection pulse generation circuit. Name of agent: Patent attorney Toshio Nakao and 1 other person 2nd
Figure 20 Figure 3 Figure 4 [-] Figure 7 Figure 81! lHノ

Claims (1)

[Claims] The screen surface is divided vertically and horizontally into a plurality of sections, and an electron beam is generated for each of the vertical sections, and the electron beam is deflected in the vertical and horizontal directions to display an image. The device is characterized in that the vertical focus voltage is switched between when receiving an interlace synchronization signal of the television signal used to create an image and when receiving a non-interlace synchronization signal, so that the vertical focus during non-interlace is made softer than that during interlace. image display device.