JP2001289623A - Method and element for electronic beam position detection and cathode-ray tube - Google Patents

Abstract

PROBLEM TO BE SOLVED: To perform more accurate position detection by an electron beam position detecting method which is applied to a cathode-ray tube, etc. SOLUTION: A position detecting element 121 is composed of >=2 electrodes 13a and 13b which are insulated from each other, and signals based upon beam currents generated when an electron beam spot 18 impinges on the electrodes 13a and 13b are detected to detect the position of the electron beam spot 18.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electron beam position detecting method applied to, for example, a cathode ray tube, an electron beam position detecting element, and a cathode ray tube.

[0002]

2. Description of the Related Art In general, a color cathode ray tube has a structure in which the length in the depth direction increases as the image display area increases. Also, an increase in the depth causes an increase in the electron optical magnification of the electron gun, and an increase in the image display area causes a decrease in the energy density of the electron beam on the image display area. For these reasons, it is difficult to realize high brightness and high resolution in large tubes.

[0003] A small image area as described in JP-A-11-31467 is synthesized with one of the cathode ray tubes which solve the problem of reduction in depth, high brightness and high resolution, and the whole image is formed in a large image area. There is a multi-neck cathode ray tube for drawing.

In the cathode ray tube of this type, it is important to join images between small image areas when synthesizing the small image areas. In order to perform accurate bonding, it is necessary to detect the position of the electron beam spot on the phosphor screen during electron beam scanning and feed back the position information to correct the deflection signal and the video signal.

As a method of detecting an electron beam spot position, there is a method of applying a phosphor and obtaining a signal by a photodetector (Japanese Patent Laid-Open No. 10-2839).
No. 47).

[0006]

In this optical position detection method, a color selection mechanism such as an aperture grill,
A phosphor is applied on the back side of the shadow mask or on the boundary of the small image area where there is no video signal, and the position information of the electron beam spot is obtained from the application pattern of the phosphor. In this case, in order to detect simultaneous light emission from a plurality of places, not only a plurality of photodetectors are required, but also a partition must be provided so that light emission from the phosphor does not leak to other regions. In addition, in order to obtain electron beam spot position information from a plurality of light emitting locations with one photodetector, it is necessary to completely shift the light emitting timing.

In the above case, the accuracy of image joining is insufficient, and it is difficult to follow the higher the scanning frequency in order to obtain electron beam spot information from the light emission cycle. It becomes impossible to display the entire image.

The present invention has been made in view of the above circumstances, and provides an electron beam position detecting method capable of detecting the position of an electron beam spot with higher accuracy. The present invention provides an electron beam position detecting element that can be used in such an electron beam position detecting method. SUMMARY OF THE INVENTION The present invention provides a cathode ray tube capable of detecting a position of an electron beam spot with higher accuracy and obtaining a high-quality image.

[0009]

An electron beam position detecting method according to the present invention has a position detecting element composed of two or more electrodes insulated from each other, and an electron beam spot is obtained by hitting the electrodes. The position of the electron beam spot is detected by detecting a signal based on the beam current.

According to the electron beam position detecting method of the present invention, the electron beam hits the position detecting element composed of two or more electrodes, and the beam current is directly detected therefrom. The spot position is accurately detected.

An electron beam position detecting element according to the present invention comprises:
It is composed of two or more electrodes insulated from each other, and the position of the electron beam spot is electrically detected by hitting the electrode with the electron beam spot.

According to the electron beam position detecting element of the present invention, when an electron beam spot hits two or more electrodes,
Thus, the beam current is directly detected, and the position of the electron beam spot is electrically detected by a signal obtained from the beam current.

A cathode ray tube according to the present invention has a position detecting element composed of two or more electrodes insulated from each other,
The position detecting element is configured to electrically detect the position of the electron beam spot.

According to the cathode ray tube of the present invention, the beam current is directly detected by the position detecting element, and the position of the electron beam spot is accurately detected by a signal obtained from the beam current. Therefore, a high quality image can be obtained.

A cathode ray tube according to the present invention comprises a plurality of electron sources,
For example, a cathode ray tube that draws a large image by combining small image regions using an electron gun, or draws a large image by partially overlapping and combining small image regions, and a boundary portion between the small image regions. A position detection element composed of two or more electrodes insulated from each other, and by using this position detection element, the position of the image in the vertical and horizontal directions is adjusted so that a large image is displayed properly. It is configured to be corrected.

In the present invention, the position of the image in the horizontal and vertical directions is corrected by the position detecting elements arranged corresponding to the boundaries between the small image areas, and the display of the large image is optimized.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An electron beam position detecting method according to the present invention has a position detecting element composed of two or more electrodes insulated from each other, and a beam current obtained when an electron beam spot strikes the electrodes. To detect the position of the electron beam spot. According to the present invention, the position of the electron beam spot can be detected from the area ratio of the electron beam spot hitting each electrode of the position detecting element or the beam current ratio.

An electron beam position detecting element according to the present invention comprises:
It comprises two or more electrodes that are insulated from each other, and the position of the electron beam spot is electrically detected by hitting the electrode with the electron beam spot. According to the present invention, the position of the electron beam spot can be detected from the area ratio of the electron beam spot hitting each electrode or the beam current ratio.

A cathode ray tube according to the present invention has a position detecting element composed of two or more electrodes insulated from each other,
The position detecting element is configured to electrically detect the position of the electron beam spot. In the present invention, the area ratio of the electron beam spot hitting each electrode of the position detecting element,
Alternatively, the configuration can be such that the position of the electron beam spot is detected from the beam current ratio.

The cathode ray tube according to the present invention comprises a plurality of electron sources,
For example, a cathode ray tube that draws a large image by synthesizing a small image area using an electron gun, and a position detection element composed of two or more electrodes that are insulated from each other is arranged at a boundary between the small image areas. Then, the position of the image in the vertical and horizontal directions is corrected using this position detecting element so that a large image is properly displayed.

The cathode ray tube according to the present invention comprises a plurality of electron sources,
For example, a cathode ray tube that draws a large image by partially overlapping and combining small image regions using an electron gun, and includes two or more insulated electrodes at a boundary between the small image regions. The vertical and horizontal image positions are corrected so that a large image can be displayed properly by arranging the determined position detecting elements.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

The cathode ray tube according to the embodiment is shown in FIGS.
As shown in FIG. 2 as an example, a color for drawing a large image
This is a case where the present invention is applied to the cathode ray tube 10. This color cathode ray
The tube 10 comprises a panel 1 forming a large image area and this panel
And the funnel 2 joined to the funnel 2
Small image area that is joined and divided into multiple, in this example, nine
8 [8₁, 8_Two, 8_Three, 8_Four, 8_Five, 8₆, 8₇,
8 ₈, 8₉Nine necks 3 [3₁, 3_Two,
3_Three, 3_Four, 3_Five, 3₆, 3₇, 3₈, 3₉]
Each neck 3 has an electron gun 5 [5₁, 5 _Two,
5_Three, 5_Four, 5_Five, 5₆, 5₇, 5₈, 5₉] Is arranged
At the same time as facing the color phosphor screen 6 on the inner surface of the panel 1.
Sorting mechanism 11, such as aperture grill, shadow mass
A large image is arranged by combining a plurality of small image areas 8.
The whole image is drawn in the image area 9. 7
Indicates a deflection yoke. In this case, it is not shown
The color selection mechanism 11, for example, the aperture grill,
Has a large number of slit-shaped beam transmission holes suspended over it
The electrode plate for color selection has slit-shaped beam transmission holes on the screen.
It is arranged to extend in the vertical direction.

In this embodiment, the color cathode ray tube 1
0, a position detecting element 12 for directly and electrically detecting a beam current of an electron beam at a peripheral portion of a large image region without a video signal or at a boundary portion of a small image region 8 to detect an electron beam spot position, an example Are arranged in the arrangement pattern shown in FIG.

FIG. 3 is a schematic diagram for understanding the location of the position detecting element 12. A hatched portion 51 is an effective area that is a small image area, and 52 is an ineffective area (an area without a video signal). The arrangement pattern of the position detection elements 12 is not limited to the above example, and various patterns can be considered. For example, one position detection element 12 can be shared between small image areas.

As will be described later, the position detecting element 12 is made of a metal plate or a conductive film which is insulated from each other.
It has one or more electrodes.

FIG. 6 shows an example of the position detecting element 12.
Position detection element 12 ₁ of this embodiment, two metal plates, for example rectangular metal plate 13 [13a, 13b] and so part mutually overlapping, and so as to be electrically insulated from each other,
In this example, the resistance elements 16 [16a, 16b] are connected to the middles of the conductors 15 [15a, 15b] connected to the metal plates 13a, 13b, respectively, via an insulator 14 such as a ceramic support. It is composed. In this case, electron beams and secondary electrons are prevented from hitting the resistance elements 16a and 16b and the conductors 15a and 15b.

[0028] With this position detection element 12 ₁ above the electron beam spot 18 traverses the metal plate 13a, the electron beam 21 impinging on 13b is detected as a direct current, resistive element 1
6a and 16b, the electron beam spot 18
Is extracted as voltage pulses Pa and Pb. When the electron beam 21 strikes both of the metal plates 13a and 13b at the same time, a current proportional to the number of colliding electrons flows through each of the metal plates 13a and 13b. That is, voltage pulses Pa and Pb having magnitudes proportional to the number of colliding electrons are generated. The current density of the electron beam spot 18 is uniform, α% of the electron beam spot 18 is on the metal plate 13a, and (100−α)%
Is on the metal plate 13b, the ratio between the magnitudes of the voltage pulses Pa and Pb transmitted through the conductors 15a and 15b is α / (100−α).

Even if the current density of the electron beam spot 18 is not uniform, the same electron source (the so-called electron gun 5)
If the spot of the electron beam applied to the same point from the position always keeps the same shape, the correction is made to intersect with the boundary in the y direction, that is, the boundary line formed by overlapping the two metal plates 13a and 13b ( For example, a spot position in a direction (for example, orthogonal) can be accurately specified. When currents of exactly the same value flow from the metal plates 13a and 13b, the center of the brightness of the electron beam spot 18 is on the boundary between the two metal plates 13a and 13b in the y direction. Therefore, the location where the luminance peaks is not necessarily located on the boundary between the two metal plates 13a and 13b.

The position detection element 12 _1, the aperture grill, shadow mask, partial video signal is not the electron source side of the color selection mechanism 11 and other such, where the original a peripheral portion of the large image region not irradiated with the electron beam, In the example of FIG. 1, it can be installed at a boundary portion of a small image region, a peripheral portion of a large image region, a so-called ineffective region, by bridging or the like.

[0031] The mounting portion of the position detecting element 12 _1, regularly electron beam to be irradiated. For example, when the power is turned on, it is performed every few minutes, tens of minutes, or every several hours. Further, the position detecting element 12 ₁ is obtained with respect to the vertical direction of the whole image in the y-axis of FIG. 6, by installing it to have a certain angle, vertical electron beam spot, the positional information in the horizontal direction be able to.

The arrangement of the position detecting element 12 _1, as shown in FIG. 7, larger in consideration of the relative position between the electron source (I),
(II) and (III). For example, in FIG. 7A, the position detecting element 12 ₁ of the left edge of the screen, as shown in the pattern (I), the metal plate 13a is disposed to overlap the right portion of the metal plate 13b. Position detection element 12 ₁ of the right edge of the screen, as shown in the pattern (III), the metal plate 13a is disposed so as to overlap the left part on the metal plate 13b. Position detection element 12 ₁ of the center of the screen as shown in the pattern (II), the metal plate 13 is arranged in the same manner as the pattern (I) or pattern (III).

Then, by dividing into three patterns,
The electron beam 21 can be prevented from hitting the side surface of the metal plate 13a. Pattern (I), the position detection element 12 ₁ of the left edge of the screen and right edge of the screen shown in (III), respectively become the side surface of the metal plate 13a is in the shadow of electron beam 21, it does not strike the electron beam 21 on its side surface. On the other hand, the position detecting element 12 _{1 at the} center of the screen is configured to tilt the metal plate 13a or both the metal plates 13a and 13b with respect to the electron beam 21 as shown in a pattern (II ₁ ) in FIG. Or, as shown in pattern (II ₂ ):
There is a method of bending the metal plate 13a. With this configuration, the electron beam does not hit the side surface of the metal plate 13a.

According to the color cathode-ray tube 10 according to the present embodiment described above, by arranging the position detection element 12 ₁ formed of a metal plate 13a, from 13b, when scanning of the electron beam, with the position detecting element 12 ₁ The obtained electron beam spot position information, that is, the position information of the electron beam spot 18 obtained from the area ratio of the electron beam hitting the metal plates 13a and 13b or the ratio of the beam current is sent to the deflecting unit (so-called deflection yoke) 7. The deflection signal and the video signal to the electron gun section 5 are fed back to eliminate the image shift, the generation of the gap, and the unintended overlap when the small image areas 8 are joined.

Therefore, a plurality of small image areas 8 can be joined with high accuracy. Such a color cathode ray tube 1
0 indicates that the depth is short and a high-luminance image is obtained, and the distance from the electron gun 5 to the phosphor screen 6 is short, so that a high-resolution image with good focus can be obtained.

As in the conventional method, at least one
Since not detect a spot position from the period of the signal by the line scanning, if you know the approximate location, the electron beam 2 only on the position detecting element 12 ₁ as represented in Figure 6
The positional relationship between the video signal and the actual beam spot can also be obtained by irradiating 1 for a certain period of time, and by feeding it back, it is possible to eliminate the deviation of the image from other nearby small image areas. In addition, accurate position detection is possible even during a high-definition image display even if the scanning frequency is large.

FIG. 8 shows an example of installation of the position detecting element 12. In this example, a crosslinked body 24 having a step 23 is provided at a position where the position detecting element 12 is to be installed, and the crosslinked body 24 is provided.
The position detecting element 12 is configured by supporting the two metal plates 13a and 13b so as to be insulated from each other by using the step 23. Between the metal plates 13a, 13b and the crosslinked body 24,
An insulator is interposed to insulate each other. For example, it can be realized by forming an insulating coating film 25 on the surface of the crosslinked body 24.

Further, the electron beam 21 is applied to the metal plate 13a,
In order to irradiate only the position 13b, for example, a shielding plate 27 having an opening 26 can be provided so as to face the position detecting element 12. The shape of the opening 26 of the shielding plate 27 is not only rectangular, but also circular, elliptical, rhombic, parallelogram,
Various shapes such as polygons are conceivable.

When an aperture grill is used as the color selection mechanism 11, for example, the position detecting element 12 can be installed as shown in FIG. Aperture grill 11
Although the detailed description is omitted, a pair of opposing support members 3
There is provided a frame-like frame 35 including a pair of elasticity imparting members 33 and 34 extending between the support members 31 and 32. The support members 31 and 32 extend in one direction between the support members 31 and 32. A mask material having a large number of slit-shaped electron beam transmitting holes (not shown), that is, a color selecting electrode thin plate 36 is stretched.

On the electron source side of the aperture grill 11, the bridge 24 having the position detecting element 12 is supported by the supporting members 31 and 32 of the frame 35 so that the peripheral portion of the large image area and the boundary of the small image area. Place on the part.
Further, the shielding plate 27 can also be disposed so as to be supported by the support members 31 and 32.

FIG. 10 shows another example of the position detecting element 12. Position detecting element 12 ₂ of the present embodiment, two metal plates, for example rectangular metal plate 13 [13a, 13b] and so part mutually overlapping, and so as to be electrically insulated from each other, the present embodiment In this embodiment, the metal plate 13a and the metal plate 13b are arranged via an insulator 14 such as a ceramic support, and the resistance elements (R
₁ ) The conductor 20a is connected via the conductor 19a, the conductor 20b is drawn out from the metal plate 13b, and a resistance element (R ₂ ) 19b is connected to the middle of the conductor 20b.

[0042] According to the position detection element 12 _2, when there is no temporal variation in luminance of the electron beam, it is possible to obtain position information of the electron beam spot 18 as the magnitude of voltage (voltage pulse Pc). For example, the resistance value R ₁ of the resistance element 19a is 2R (Ω), the resistance value R ₂ of the resistance element 19b is R (Ω), and the beam current by the electron beam is a constant value I.
Assuming that (A), when 100% of the electrons in the electron beam hit the metal plate 13a, the detected voltage is V = 3IR, and when 50% hits the metal plate 13a and 50% hits the metal plate 13b, V = 3IR. = 2IR, and when 100% hits the metal plate 13b, V = IR. FIG. 11 is a graph showing this relationship. The position detection element 12 ₂ may be used in place of the position detection element 12 ₁ described above.

In the position detecting elements 12 ₁ and 12 ₂ shown in FIGS. 6 and 10, two metal plates are used, but the number is not limited to two. It is also possible to configure the position detecting element using two or more metal plates. The conductive film is not limited to a metal plate, but may be a substrate formed with a required conductive film such as a metal-plated substrate.

FIGS. 12A to 12E show other examples of the position detecting element 12 having an electrode pattern different from those of FIGS. 6 and 10, respectively. Each example is a diagram viewed from a plane. FIG.
The four electrodes 401, 402, 403, 404 is an example in which the position detection element 12 ₃ are arranged in shape of field. FIG. 12B combines two electrodes 405 and 406,
As an L-shape to each other, an example in which the position detection element 12 ₄ arranged in a rectangular shape as a whole. FIG. 12C
Is a square in which the vertex of the isosceles triangle of the electrode 407 is located at the center so that one electrode 407 has an isosceles triangle and the other electrode 408 has the remaining shape. an example in which the position detection element 12 ₅ are arranged in the shape. FIG. 12D shows two electrodes 4
09 and 410 are combined so as to form a comb-tooth shape, and are arranged in a rectangular shape as a whole, and the position detecting element 12 _{6 is formed.}
This is an example of the configuration. FIG. 12E shows two electrodes 412,
413, in combination such that the serrated each other, an example in which the position detection element 12 ₇ are arranged in a square shape as a whole. Each of the electrodes shown in FIGS.
They are not in contact with each other and are electrically insulated.

In the above example, the present invention is applied to the color cathode ray tube 10 which combines a plurality of small image areas 8 and draws the whole image in the large image area 9. However, the present invention requires the position information of the electron beam spot. To other cathode ray tubes, image display devices, and other devices.

The method for detecting the position of an electron beam using the position detecting element 12 of the present invention is suitable for application to a device including a cathode ray tube and an image display device which needs to detect the position of an electron beam spot.

In the present invention, the position detecting element 12 described above is used.
Since the electron beam spot position is detected, for example, as shown in FIG.
As shown in FIG.₁And small image area 8_TwoBetween
Electron beam spot 18₁And electron beam spot 18_Two
, Ie, the electron beam spot 18₁And 18
_TwoIf the luminance center positions of
Brightness center of electron beam spot, for example, small image area 8_Two
Electron beam spot 18_TwoBased on the luminance center position of
And small image area 8₁Electron beam spot 18 ₁Brightness
Adjust the center position, that is, move the small image area up and down, left and right
Combines images with other small image areas that are close to each other
can do. In this case, the electron beam 1
8₁, 18_TwoFor a predetermined period, for example, a few seconds.
The deflection yoke can be controlled and adjusted between
You.

FIG. 14 shows that a vertical displacement between the small image areas 8 ₁ and 8 ₂ is detected by the position detecting element 12, and the detection signal is fed back to, for example, a deflection yoke to correct the electron beam scanning, thereby obtaining a large image. Here is an example in which is displayed properly. 14A is small image regions 8 adjacent in the horizontal direction ₁ and 8 ₂
Are vertically shifted at the image area boundary 60. Incidentally, reference numeral 61 denotes one pixel. In this example, the position detecting elements 12 are arranged across the image area boundary 60. For example, the electron beam 21 that scans _one small image area 81 irradiates the metal plate 13a of the position detecting element 12 with, for example, 44% of the beam spot area, and the metal plate 13b receives the remaining 56%. is irradiated, electron beam 21 for scanning the other of the small image area _82, the metal plate 1 of the position detection element 12
It is assumed that, for example, 95% of the beam spot area is irradiated to 3a, and the remaining 5% is irradiated to the metal plate 13b.

In this case, the small image area 8₁Scanning electron
Small image area 8 based on the beam position₁Location check
The detection signal detected by the output element 12 and the small image area 8_Twoso
Difference signal from the detection signal detected by the position detection element 12
Is the small image area 8_TwoDeflection yaw with side beam deflection
Feedback to the small image area 8 _Two
The electron beam that scans the small image area 8 is corrected._TwoIs small
14B, and moves downward without any misalignment as shown in FIG. 14B.
It is displayed as an appropriate large image.

The color cathode ray tube 10 shown in FIG.
Small image areas 8 where electron beams from each electron gun 5 are adjacent to each other
Scan to the small image area boundary without overlapping
This is an example in which a large image is drawn.

FIGS. 4 and 5 show another embodiment of the color cathode ray tube of the present invention. FIG. 4 shows a schematic configuration of a color cathode ray tube, and FIG. 5 is an enlarged view of a main part thereof. The color cathode ray tube 70 according to the present embodiment includes a panel 1 forming a large image area, a funnel 2 joined to the panel 1 and a plurality of
In this example, the small image area 8 divided into nine [8 ₁ , 8 ₂ ,
8 _3, 8 _4, 8 _5, 8 _6, 8 _{7, 8} 8, 9 corresponding to 8 _9] one neck 3 [3 _1, 3 _{2, 3} 3, 3 _4, 3 _5, 3
_6, 3 _7, 3 _8, 3 _9] and has a tubular body 4 made from an electron gun 5 [5 ₁ each neck 3, 5 _2, 5 _3, 5 _{4, 5} 5, 5
₆ , 5 ₇ , 5 ₈ , 5 ₉ ], and a color selection mechanism 11, for example, an aperture grill, a shadow mask, etc., for the color fluorescent screen 6 on the inner surface of the panel 1.
Reference numeral 7 denotes a deflection yoke. In this case, although not shown, the color selection mechanism 11, for example, an aperture grill, has a plurality of slit-shaped beam transmission holes stretched on a frame. It is arranged to extend in the horizontal direction. In the present example, in particular, a plurality of small image regions 8 are combined so as to partially overlap between the small image regions 8 adjacent to each other, and the entire image is drawn in the large image region.

That is, as shown in FIG.
Is scanned so as to partially overlap the adjacent small image area 8. The region A is a region where scanning of the electron beam 21 partially overlaps at a boundary between adjacent small image regions. Then, in the present embodiment, the position detection element 12 is disposed at the periphery of the large image area where there is no video signal on the electron gun side of the color selection mechanism 11 and at the boundary between the small image areas 8 as described above. In this color cathode ray tube 70 as well, the position detection element 12 can correct the horizontal and vertical displacement of the image between the small image areas 8 and display an appropriate large image in the same manner as described above. In this case, the electron beams overlap in the region A of FIG. When the electron beam is deflected further, the electron beam
It hits the shielding plate 71 and does not hit the phosphor screen 6 (FIG. 5A).
reference). The electron beams 21 and 22 are stopped for a predetermined period, for example, a few seconds, on the position detecting element 12 according to the present invention which is set in a region where the electron beam does not hit the phosphor screen even when deflected, and the deflection yoke is controlled and adjusted during this period. can do. In region A the electron beam scanning overlap, the brightness 72 ₁ of the electron beam that scans the small image area _81, and the luminance 72 ₄ decreases gradually in the electron beam scanning the small image area 8 _4, resulting in two The total brightness by the electron beam is made to be constant at any position (see FIG. 5B).

[0053]

According to the electron beam position detecting method of the present invention, the position of the electron beam spot can be electrically detected by the position detecting element with high accuracy. When detecting the position of the electron beam spot from the area ratio of the electron beam spot hitting each electrode of the position detection element or the beam current ratio, detection can be performed at the boundary position between the electrodes, and the detection of the electron beam spot position with higher accuracy Becomes possible.

According to the electron beam position detecting element according to the present invention, the electron beam spot position can be electrically detected with high accuracy. When detecting the position of the electron beam spot from the area ratio of the electron beam spot hitting each electrode of the position detection element or the beam current ratio, detection can be performed at the boundary position between the electrodes, and the detection of the electron beam spot position with higher accuracy Becomes possible.

According to the cathode ray tube of the present invention, the position of the electron beam spot can be electrically detected with high accuracy, and a high-quality and high-resolution image can be obtained. When detecting the position of the electron beam spot from the area ratio of the electron beam spot hitting each electrode of the position detection element or the beam current ratio, detection can be performed at the boundary position between the electrodes, and the electron beam spot position is detected more accurately can do.

When the cathode ray tube according to the present invention is applied to a cathode ray tube which draws a large image by synthesizing a plurality of small image regions by using a plurality of electron guns, the position detecting element can be used to set boundaries between the small image regions. It is possible to join the images with high accuracy in the portions, shorten the depth of the cathode ray tube, and display a high-luminance, high-resolution whole image.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a color cathode ray tube according to an embodiment of the present invention.

FIG. 2 is a front view of the color cathode ray tube of FIG.

FIG. 3 is a configuration diagram showing an example of the arrangement of position detection elements in the color cathode ray tube of FIG. 1;

FIG. 4 is a configuration diagram of a color cathode ray tube according to another embodiment of the present invention.

FIG. 5A is an enlarged view of a main part of the color cathode ray tube of FIG. 4; FIG. 13 is an explanatory diagram of luminance in a region A;

FIG. 6 is a configuration diagram illustrating an example of a position detecting element of the position detecting element according to the present invention.

FIG. 7 is an explanatory diagram showing an example of the arrangement of electrodes of the position detecting element in consideration of the electron beam incident direction. B It is explanatory drawing which shows the example of a different arrangement | positioning of the electrode of a position detection element in the case of FIG. 6A (II).

FIG. 8 is a perspective view illustrating an example of installation of a position detection element.

FIG. 9 is a configuration diagram illustrating an example in which a position detection element is provided on a color selection electrode.

FIG. 10 is a configuration diagram showing another example of the position detection element according to the present invention.

FIG. 11 is a graph used to describe the operation of the position detection element in FIG.

12A to 12E are plan views showing other examples of the electrode pattern of the position detection element according to the present invention.

FIG. 13 is an operation explanatory diagram for explaining the present invention;

FIG. 14 is an explanatory diagram for correcting a positional shift between small image areas A and B.

[Explanation of symbols]

1 ... panel, 2 ... funnel 3 ... neck, 5 [5 ₁ to 5 _9], 6 ... phosphor screen, 7 ... deflection yoke, 8 [8 _{1-8 9],} ..Small image areas, 9 ...
Large image area, 10: color cathode ray tube, 11: color selection mechanism, 12 [12 ₁ , 12 ₂ , 12 ₃ , 12 ₄ , 1
2 ₅ , 12 ₆ , 12 ₇ ] ··· Position detecting element, 13 [1
3a, 13b] ... metal plate, 14 ... insulator, 15
[15a, 15b], 20 [20a, 20b] ... conductor, 16 [16a, 16b], 19 [19a, 19b]
... resistor element, 18, 18 ₂ , 18 ₂ ... electron beam spot, 21 ... electron beam, 24 ... cross-linked body, 25 ... insulating coating film, 26 ... opening,
27 shield

Claims (8)

[Claims] An electron beam spot detecting a signal based on a beam current obtained when the electron beam spot strikes the electrode to detect a position of the electron beam spot; An electron beam position detection method comprising detecting a position. 2. The electron beam position detecting method according to claim 1, wherein the position of the electron beam spot is detected from an area ratio of an electron beam spot hitting each electrode of the position detecting element or a beam current ratio. . 3. An electron device comprising two or more electrodes that are insulated from each other, and configured to electrically detect an electron beam spot position by irradiating the electrode with an electron beam spot. Beam position detecting element. 4. The electron beam position detecting element according to claim 3, wherein a position of the electron beam spot is detected from an area ratio of the electron beam spot hitting each of the electrodes or a beam current ratio. 5. A cathode ray tube having a position detecting element composed of two or more electrodes insulated from each other, wherein the position detecting element electrically detects the position of an electron beam spot. 6. The cathode ray tube according to claim 5, wherein a position of the electron beam spot is detected from an area ratio of an electron beam spot hitting each electrode of the position detecting element or a beam current ratio. 7. A cathode ray tube which draws a large image by synthesizing a small image region using a plurality of electron sources, comprising a plurality of electrodes insulated from each other at a boundary between the small image regions. A cathode ray tube, wherein a position detection element is arranged, and the position of the image in the vertical and horizontal directions is corrected using the position detection element so that the large image is properly displayed. 8. A cathode ray tube that draws a large image by using a plurality of electron sources and partially overlaps and combines small image regions, wherein the cathode ray tube is insulated from each other at boundaries between the small image regions. A position detection element composed of two or more electrodes is arranged, and the position of the image in the vertical and horizontal directions is corrected using the position detection element so that the large image is displayed properly. And a cathode ray tube.