JPH0456416B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a cathode ray tube (CRT) for use in oscilloscopes, storage oscilloscopes, etc.
More specifically, the present invention relates to a deflection magnifying electron lens for a cathode ray tube.

[Conventional technology and its problems]

Placing a cylindrical deflection magnifying electron lens between the deflection system and the screen is known, for example, as disclosed in Japanese Patent Application Laid-Open No.
Publication No. 134531, Japanese Patent Publication No. 60-65436, Japanese Patent Publication No. 1986-65436
It is disclosed in Publication No. 60-23939 and the like. The first deflection-magnifying electron lens disclosed in JP-A-59-134531 includes two cylindrical electrodes constituting a quadrupole lens, and further has a slot lens at the entrance of the quadrupole lens and an aperture lens at the exit. Therefore, the structure of this deflection magnifying lens is very complicated, and the usable effective diameter of the lens is small.

On the other hand, the deflection magnifying electron lenses disclosed in Japanese Patent Application Laid-open Nos. 60-65436 and 60-23939 include a quadrupole lens consisting of electrodes with a rectangular cross section, and have a relatively simple structure. However, a specific method for producing an electron lens with high sensitivity and short overall length is not disclosed.

Therefore, the present applicant disclosed a highly sensitive polarizing magnifying lens with a relatively simple structure in Japanese Patent Application No. 88732/1983. The deflection magnifying electron lens disclosed herein is composed of a combination of two cylindrical electrodes, and has a space surrounded by a pair of surfaces of the first cylindrical electrode and a pair of surfaces of the second cylindrical electrode. . The paired surfaces of the first cylindrical electrodes have long tongues that surround the space.

By the way, even greater deflection magnification (deflection sensitivity)
may be required. SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a deflection magnifying lens that can obtain a large deflection magnification ratio with a simple configuration.

[Means for solving problems]

To achieve the above object, the present invention will be described with reference to the reference numerals in the drawings showing the embodiments. a second deflection system for deflecting the electron beam in a second direction perpendicular to the first direction; a screen for impacting the electron beam emitted from the electron gun; and a screen for impacting the electron beam emitted from the electron gun; at least a deflection magnifying electron lens disposed between the means and the screen, the deflection magnifying electron lens comprising first and second cylindrical electrodes 18, 19 coaxially arranged; The first cylindrical electrode 18 has an x-
A first pair of surfaces 2 arranged symmetrically around the z-plane
1 and 22, and a second pair of surfaces 23 and 24 arranged symmetrically about the yz plane, and the second cylindrical electrode 19 has a second pair of surfaces 23 and 24 arranged symmetrically about the xz plane. a third pair of surfaces 27, 28, and a fourth pair of surfaces 29, 30 arranged symmetrically about the yz plane; A pair of tongue-like parts 25 and 26 protruding from each other are provided, and the fourth tongue part 25 and 26 are provided on both sides of the opposing space of the pair of tongue-like parts 25 and 26.
The first and second cylindrical electrodes 18 and 19 are arranged such that the pair of surfaces 29 and 30 are located, and the traveling direction of the electron beam deflected in the first direction by the first deflection system is The first and second cylindrical electrodes 1
The quadrupole lens composed of 8 and 19 produces an effect of inverting and expanding the deflection, and
A potential is applied to the first and second cylindrical electrodes 18 and 19 so that the electron beam deflected in the second direction by the deflection system is deflected and expanded by the quadrupole lens. In a cathode ray tube provided with potential applying means, the tongue-like portions 25 and 26 extend in the x-axis direction in the xz plane.
The protrusions 41 and 42, which protrude in the direction of narrowing the opposing distance between the tongues 2 and 42 and which are opposed to each other, are
5 and 26, and the projections 41 and 42 strengthen deflection expansion in the x-axis direction and the y-axis direction.

[Effect]

A strong quadrupole lens is formed near the protrusions 41 and 42 provided on the pair of tongues 25 and 26 of the present invention, so that the deflection magnification can be easily increased.

[First Embodiment] Next, a CRT of an oscilloscope according to a first embodiment of the present invention will be described. CRT shown in Figure 1
includes an electron gun 5 consisting of a cathode 2, a control grid 3 and an anode 4 in an evacuated tube 1. The path of the electron beam emitted from the electron gun 5 includes an aberration correction electron lens 6, first and second quadrupole lenses 7, 8, a vertical deflection system 9, a third quadrupole lens 10, a horizontal deflection system 11, Polarizing magnifying lenses 12 according to the present invention are sequentially arranged. The fluorescent screen 13 is constructed by coating a face plate 14 with a fluorescent substance 15 and providing a conductive layer 16 thereon. A rear acceleration electrode 17 is provided on the inner wall of the funnel portion 1a of the tube body 1, and this rear acceleration electrode 17 is connected to the conductive layer 16 of the fluorescent screen 13.

The deflection magnifying lens 12 according to the present invention consists of first and second cylindrical electrodes 18, 19, the first cylindrical electrode 18 is connected to the ground, and the second cylindrical electrode 1
9 is arranged so as to be slightly surrounded by the rear acceleration electrode 17, and is connected to the rear acceleration electrode 17 by a conductive wire 20.

The cathode 2 of this CRT has a DC voltage of -2kV, for example, and the control grid 3 has a DC voltage of 0.
Low to about 100V, e.g. -2.1kV, anode 4
is 0V (ground potential), aberration correction electronic lens 3
5 has a positive and negative voltage of -50 to +50V, the first, second and third quadrupole lenses 7, 8 and 10 have positive and negative voltages of 0 to 400V, and the rear accelerating electrode 17 has a +14kV, the deflection magnifying electron lens 12 according to the present invention. The first cylindrical electrode 1 of
8 is 0V (ground potential), second cylindrical electrode 19
The same +14 kV as that applied to the rear acceleration electrode 17 is applied to the electrode.

The structure and operation of the CRT other than the deflection magnifying electron lens 12 are the same as those of known CRTs, and the electron beam emitted from the cathode 2 is transmitted to the control grid 3.
After the amount thereof is controlled, it passes through the anode 4 and the aberration correction electronic lens 6 and enters the first quadrupole lens 7. The first quadrupole lens 7 is now horizontally (second
If x is the direction (direction of Dissipate. The second quadrupole lens 8 diverges the electron beam in the xz plane and focuses it in the yz plane. The third quadrupole lens 10 directs the electron beam to
It is focused in the z plane and diverged in the yz plane. The vertical deflection system 9 deflects the beam in the vertical (y) direction in response to the vertical deflection signal (observation signal) supplied thereto, and the horizontal deflection system 11 deflects the beam in the vertical (y) direction in response to the ramp voltage supplied from the sweep circuit. Deflect the beam in the horizontal (x) direction.

The deflection magnifying electron lens 12 according to the invention focuses the electron beam in the yz plane and diverges it in the xz plane. An electron beam that enters this deflection and expansion electron lens 12 with deflection angles in the x and y directions is deflected and expanded in both the x and y directions. The second cylindrical electrode 19, to which the same high voltage as the latter-stage accelerating electrode 17 is applied, accelerates electrons and increases the brightness of the image on the screen. Note that the beam that is vertically deflected and enters the deflection magnifying lens 12 is subjected to a strong focusing action, and its traveling direction is reversed.

Next, the deflection magnifying lens 12 according to the first embodiment of the present invention will be explained in more detail with reference to FIGS. 2 to 10. As is clear from FIG. 3, the first cylindrical electrode 18 has a first pair of surfaces 21 and 22 and a second
consists of a pair of planes 23 and 24, an x-z plane and a y
- They are each formed symmetrically about the z plane. Second
The lengths of the pair of surfaces 23 and 24 are the lengths of the first pair of surfaces 21 and 24, respectively.
Since it is significantly shorter than 22, the four sides 21, 22, 2
3 and 34, a pair of tongue-like portions 25 and 26 are formed that protrude in the screen direction beyond the second pair of surfaces 23 and 24. The pair of tongues 25, 26 have two edges 25a, 25b, 26a, 26b that are parallel to each other and extend linearly in the screen direction. Tip portion 25 of a pair of tongue-like portions 25 and 26
c and 26c are curved lines appropriate for correcting pattern distortion, and are slightly arched and concave toward the cathode side, as is clear from FIG. The edges of the cutout portions 23a and 24a of the second pair of surfaces 23 and 24, that is, the edges 23a and 24a on the screen side, are also made into appropriate curves to correct pattern distortion, and in this example, as is clear from FIG. It is concave in an arch shape towards. First and second pair of surfaces 2
1, 22, 23, and 24 are convex toward the tube axis in order to obtain a field that approximates an ideal hyperbolic equipotential field, as is clear from FIGS. 2, 3, and 6. It is formed into a quadratic curved surface (hyperbolic surface). Note that the first pair of surfaces 21 and 22 are x-
The second pair of surfaces 23, which are arranged along the z-plane,
24 is arranged along the yz plane.

The pair of tongues 25 and 26 have protrusions 41 and 42 that extend in the x direction in a band shape and protrude in the tube axis direction. The protrusions 41 and 42 face each other and are provided near the tips 25c and 26c of the tongues 25 and 26. Note that each of the protrusions 41 and 42 is formed by pressing so that a recess is formed on the outer surface of each of the tongues 25 and 26.

As is clear from FIG. 2, the second cylindrical electrode 19 has a third pair of surfaces 27 and 28 and a fourth pair of surfaces 2.
9 and 30, formed symmetrically with respect to the x-z plane and the y-z plane, respectively, and arranged so as to surround at least one pair of tongues 25 and 26 of the first cylindrical electrode 18. . The third pair of surfaces 27, 28 are x
− arranged along the z plane, and the fourth pair of planes 2
9 and 30 are arranged along the yz plane, and both surfaces are formed into quadratic curved surfaces (bihedral surfaces) convex toward the tube axis.

As is clear from FIGS. 4 and 5, the width W ₁ of the first pair of surfaces 21 and 22 is the same as that of the second pair of surfaces 23 and
24, and the width W ₃ of the third pair of surfaces 27, ₂₈ is somewhat narrower than the width W ₄ of the fourth pair of surfaces 29, 30. second pair of surfaces 23,
The width W ₂ of 24 is the width W ₃ of the third pair of surfaces 27 and 28.
approximately equal to. Therefore, the first pair of surfaces 21, 22, ie the pair of tongues 25, 2 on the y-axis in FIG.
6 and the fourth pair of surfaces 2 on the x-axis.
The facing distances of 9 and 30 are approximately equal.

In order to obtain an ideal hyperbolic equipotential field as shown by equipotential lines 31 in FIG. 6, W ₂ = W ₃
It is desirable that W ₂ −0.2≦W ₃ <W ₂ +
If W ₂ and W ₃ are determined to satisfy 0.2W ₂ , then
It has been confirmed that a near-ideal quadrupole lens field can be obtained. Considering the electric discharge between the first cylindrical electrode 18 and the second cylindrical electrode 19, W ₄ −
It is desirable to satisfy W ₂ > 6 mm, W ₃ - W ₁ ≧ 6 mm, and in this example, W ₁ = 16 mm, W ₂ = 20 mm,
W ₃ = 24mm, W ₄ = 28mm. Each side 2
1, 22, 23, 24, 27, 28, 29, 30
The curves are determined in such a way that an equipotential field of a rectangular hyperbola x ² −y ² =a ² is obtained in the space of the tongues 25, 26.

Tips 25c, 26 of the pair of tongues 25, 26
The shape of c is related to pattern distortion; if it is concave in an arch shape toward the cathode side, the emission line parallel to the x-z plane tends to have barrel distortion, and if it projects in an arch shape toward the screen side, , there is a tendency for pink tension distortion. In addition, the tip portions 25c, 2
As the arch-shaped depression of 6c becomes larger, x
Directional deflection straightness increases. If the amount of recesses at the tips 25c and 26c of the deflection magnifying lens having the structure of this example is set appropriately, the emission line parallel to the x-z plane will be distortion-free, and if the recess is made deeper, the line parallel to the x-z plane will become undistorted. Barrel distortion occurs in the emission line. Further, as the recesses of the tip portions 25c and 26c become deeper, the directness of deflection in the x direction increases.
Note that the shapes of the tips 25c and 26c slightly affect the emission lines parallel to the y-z plane, but this influence is much smaller than the shapes of the ends 23a and 24a of the second pair of surfaces 23 and 24. small.

It is desirable that the ends 23a, 24a of the second pair of surfaces 23, 24 on the screen side are arched and recessed toward the cathode side. These ends 23a, 24a
The shape affects the pattern distortion of emission lines parallel to the yz plane and the polarization straightness in the x and y directions. If the depth of the depressions at the ends 23a and 24a is kept constant, and the curve of the depressions is varied into a parabola, a hyperbola, a y ⁿ curve, etc., and the curvature at the center of the depression is increased, a curve parallel to the y-z plane can be created. The shape of the emission line changes in the barrel direction, and the deflection straightness in the x and y directions increases. Also, the end 2
If the depth of the depression is increased without changing the types of curves 3a and 24a, the emission line parallel to the y-z plane changes in the barrel direction, and the deflection linearity in the x and y directions increases. .

From the center of the tips 25c, 26c of the tongues 25, 26 to the ends 23a, 2 of the second pair of surfaces 23, 24
4a in the axial direction to the _center , and the linearly extending edges 25a of the tongues 25, 26,
The heights L ₁ of the quadrupole lenses 25b, 26a, and 26b are related to the strength of the quadrupole lens, and as it becomes longer, both the concave lens effect in the x direction and the convex lens effect in the y direction become stronger, and the deflection sensitivity improves. However, the length _L1 affects the deflection directness in the y direction, and as _L1 becomes shorter, the deflection directness in the y direction increases, and as it becomes longer, it contracts, so it must be set to an appropriate value. Must be. According to experiments, the second pair of surfaces 2 are
x to the center of the ends 23a, 24a of 3, 24
It has been confirmed that when the axial distance L ₃ is preferably within the range of W ₂ ±0.2W ₂ , the deflection straightness in the y direction is improved.

As is clear from the above, in this deflection magnifying lens, if the length of the tongues 25, 26 is changed, the deflection straightness in the y direction changes, and the shape of the tips 25c, 26c of the tongues 25, 26 changes. If you let it, x-z
The shape of the emission line parallel to the surface and the deflection straightness in the x direction change, and the end portions 23a of the second pair of surfaces 23 and 24,
By changing the shape of 24a, the shape of the bright line parallel to the yz plane changes. Note that the ends 23a, 24
Although the deflection straightness in the x direction also changes due to the change in the shape of a, this is extremely small compared to the change in the deflection straightness in the x direction due to changes in the tongues 25 and 26. Further, the change in the deflection straightness in the y direction due to the change in the shape of the end portions 23a, 24a is
It can be corrected by changing the length _L1 . Therefore, if one of the shape of the emission line parallel to the x-z plane and the polarization straightness in the x direction can be changed without significantly affecting the other, the x-z
The shape of the bright line parallel to the plane and the bright line parallel to the yz plane, and the polarization straightness in the x and y directions can all be set optimally. In the deflection magnifying lens of this example, as W ₂ /W ₁ increases, x
Since the deflection straightness in the x direction is reduced without significantly changing the shape of the emission line parallel to the −z plane, the above-mentioned best setting can be achieved by adjusting W ₂ /W ₁ .

The length of the second cylindrical electrode 19, that is, from the tip of the first pair of tongues 25c, 26c to the second cylindrical electrode 19.
As the distance to the screen side edges 27a, 28a of
The shapes of the emission lines parallel to the z-plane both change in the barrel direction, and the deflection straightness in the x and y directions is both extended.
Further, the third pair of surfaces 27 of the second cylindrical electrode 19,
When the screen-side ends 27a and 28a of 28 are arched curves protruding toward the screen, the shapes of the bright lines parallel to the x-z plane and the y-z plane both change in the barrel direction. , and the deflection straightness in the x and y directions is extended. Also, end 27
If a and 28a are made into an arch shape concave toward the cathode, the characteristics will be opposite to those obtained when they are made to protrude toward the screen.

In this example, the voltage of the rear accelerating electrode 17 and the second cylindrical electrode 19 is 14 kV (16 kV with respect to the cathode).
However, as this voltage is increased, the lens effect becomes stronger and the deflection sensitivity in the x and y directions improves. Also, at this time, the deflection straightness in the x direction and the y direction is contracted, and the bright line parallel to the xz plane changes to the barrel direction, and the bright line parallel to the yz plane changes to the pink tension direction.

As shown in FIG. 7, the beam 32 is deflected in the horizontal direction (x direction) and is incident on the first cylindrical electrode 18.
is deflected and expanded in the horizontal direction by a concave lens action determined by the distribution of equipotential lines 33 in the xz plane.

As shown in FIG. 8, the beam 34a is deflected in the vertical direction (y direction) and is incident on the first cylindrical electrode 18.
or 34b is focused by a convex lens action determined by the distribution of equipotential lines 35 in the y-z plane;
Its traveling direction is reversed so that it crosses the xz plane, and the beam is deflected and magnified. In this deflection magnifying lens, the beams 34a and 34b intersect the xz plane within the space in which the pair of tongues 25 and 26 face each other. Such a lens effect can be obtained by increasing the length L ₁ of the tongues 25 and 26. Beams 34a, 34
If the intersection of b with the xz plane is within the space where the tongues 25 and 26 face each other, there is a focusing effect even after the intersection, and this focusing effect increases as the amount of deflection in the y direction increases. Therefore, the effect of reducing the deflection straightness in the y direction is produced. Therefore, by adjusting the lengths of the tongues 25 and 26, the directness of the deflection in the y direction can be improved.

As shown in FIG. 6, the opposing spaces between the tongues 25 and 26 include a pair of tongues 25 and 26 with 0V (2kV to the cathode) and a +14kV (to the cathode)
16kV) and a second pair of surfaces 29, 30. And a pair of tongue-shaped parts 2 on the y-axis
The mutual spacing between the surfaces 5 and 26 is equal to the mutual spacing between the pair of surfaces 29 and 30 on the x-axis. Therefore, an ideal quadrupole lens field is formed as shown by equipotential lines 31. Therefore, the effective utilization area, that is, the pore diameter ratio increases. In this example, the ratio W _y /W ₂ between the lens effective area W _y and W ₂ in the y-axis direction is 0.85, x
The ratio of the axial lens effective area W _x to W ₁ is W _x /W ₁
0.5, each of which is significantly larger than a conventional polarizing magnifying lens.

When the tongues 25 and 26 are provided with the protrusions 41 and 42 facing each other, as shown in FIG.
Equipotential lines 35 are formed that are narrowed between 1 and 42 and widen on the cathode side, making it possible to obtain a strong quadrupole lens. Therefore, the deflection sensitivity in the y direction is
2.7V/cm, and the deflection sensitivity in the x direction is 1.8V/cm.

Depending on the geometry and position of the protrusions 41, 42, the deflection magnification (sensitivity) and the amount of deflection straightness distortion (pincussion or barrel pattern distortion) vary. End 23 of second pair of surfaces 23, 24
The distance L ₂ from the center of a, 24a to the center of protrusions 41, 42 is such that the beam deflected in the y direction
The point intersecting the −z plane is determined to be located near the center of the protrusions 41 and 42 in the z direction. in this way
By determining L ₂ and increasing the amount of protrusion, that is, the height T, of the protrusions 41 and 42, the quadrupole lens effect becomes stronger, and a large deflection magnification ratio can be obtained in both the x and y directions. Note that, in general, as L ₂ becomes shorter, the deflection directness in the y direction increases, and as L 2 becomes shorter, it contracts. As the height T of the protrusions 41 and 42 increases, the horizontal bright line pattern changes in the barrel direction, the vertical bright line pattern also changes in the pink tension direction, and the deflection straightness in the x direction increases. Such changes include L ₂ , the length of the protrusion 41 X ₁ , and the protrusion 41
This can be adjusted by changing the pattern of the edges 43, 44 extending in the x-axis direction, ie, D ₁ , D ₂ in FIGS. 9 and 10.

In addition, in this CRT, the distortion of the deflection straightness in the x direction and the y direction can be made less than 3% on a tube surface of 10×8 cm.

[Second Embodiment] Next, the second embodiment of the present invention shown in FIGS.
The deflection magnifying lens 12a according to the embodiment will be explained. However, in this embodiment and other embodiments described below, parts that are substantially the same as those in FIGS. 1 to 10 are given the same reference numerals, and their explanations will be omitted.

The first cylindrical electrode 18 of the deflection magnifying lens 12a shown in FIG. 11 has substantially the same structure as that shown in FIGS. 2 and 3, and has the same function. The second cylindrical electrode 19 of FIG. 1 is substantially identical in function to that designated by the same reference numeral in FIG.
9 and 30 have a second pair of tongues 36 and 37 arranged in series with the first cylindrical electrode 18. That is, the first cylindrical electrode 18 and the second cylindrical electrode 19 are placed opposite to each other with the gap 38 in between. The second tongues 36 and 37 are arranged on an extension plane of the second pair of surfaces 23 and 24 of the first cylindrical electrode 18 and form the first pair of tongues 25 and 26. It is formed to compensate for the notches in the second pair of surfaces 23 and 24 caused by this. Therefore, the first
a pair of tongues 25, 26 and a second pair of tongues 3;
A space surrounded by 6 and 37 is created as shown in FIG. This deflection magnifying lens 12a is x-
formed symmetrically around the z-plane and the y-z plane, respectively,
In addition, W ₁ , W ₂ in FIGS. 13 and 14,
Since W ₃ and W ₄ are set equal, the first
The electric field field in the space surrounded by the second pair of tongues 25, 26, 36, and 37 becomes an ideal quadrupole lens field as shown in FIG. 6, and the same effect as in the first embodiment is obtained. can get. Of course, the effects of the protrusions 41 and 42 can also be obtained in the same manner as in the first embodiment.

[Third Embodiment] FIGS. 15 to 20 show a deflection magnifying lens 12b according to a third embodiment of the present invention. The deflection magnifying lens 12b shown here is similar to each cylindrical electrode 18, 1 of the deflection magnifying lens 12 shown in FIGS. 1 to 10.
9 each side 21, 22, 23, 24, 27, 28,
29 and 30 are made flat. In this way, even if the surface is flat, the length L ₁ of the tongue-shaped parts 25, 26 shown in FIGS. 17 to 19, the widths W ₁ , W ₂ of each part,
If W ₃ and W ₄ are set almost the same as in the first embodiment, a near-ideal quadrupole will be created in the space surrounded by the pair of tongues 25 and 26 and the pair of surfaces 29 and 30 shown in FIG. A lens field can be obtained, and almost the same effects as in the first embodiment can be obtained.

[Fourth Embodiment] FIGS. 21 and 22 show a deflection magnifying lens 12c according to a fourth embodiment of the present invention. This deflection magnifying lens 12c is similar to the deflection magnifying lens 12a shown in FIG.
Each surface is made flat, and each surface 21, 22, 23, 24 of the first and second cylindrical electrode 18, and each surface 27, 28, 29 of the second cylindrical electrode 19,
30 is considered to be a flat surface. Since the other points are the same as the embodiment shown in FIG. 11, almost the same effects can be obtained.

[Fifth Embodiment] The protrusions 41 and 42 in the deflection magnifying lens 12d of the fifth embodiment shown in FIGS. 23 to 27 are formed by bending the tips of the pair of tongues 25 and 26 in the tube axis direction. It is formed by. These bent protrusions 41 and 42 also have the same function as in the first to fourth embodiments, and the quadrupole lens becomes strong in this vicinity, and the protrusions 41 and 42 are large in both the x and y directions.
Deflection magnification rate, by changing the geometric pattern of
Deflection directness changes. As shown in FIGS. 26 and 27, the length of the bent protrusions 41 and 42 in the x-axis direction is X ₁ , the width of the central curved portion 45 is X ₂ , and the protrusion from the x-z plane that coincides with the tube axis 41, ₄₂ , the distance from the x-z plane to the end of the central curved part 45 is _Y2 , and the distance from the x-z plane to the end of the bent protrusions 41, 42 is Y. ₃ , the tongue-shaped parts 25, 26 from the x-z plane
When the distance to Y is the distance between the center of the screen-side ends 23a and 24a of the second pair of surfaces 23 and 24 and the bent protrusions 41 and 42 (the depth of the notch), L The position where the beam deflected in the y direction intersects the x-z plane is the bending protrusion 4.
1 and 42 and the value of Y ₁ is made small, the quadrupole lens near the bent protrusions 41 and 42 becomes stronger. Generally, as L becomes shorter, the deflection straightness in the y direction increases, and as L becomes longer, it contracts. The increase in the deflection magnification ratio (increase in the quadrupole lens strength) is mainly caused by the decrease in the value of Y ₁ . As Y ₁ becomes smaller, the deflection directness in the y direction contracts, and the deflection directness in the x direction also contracts. Further, the horizontal bright line pattern changes in the barrel direction, and the vertical bright line pattern changes in the pink tension direction. These can be adjusted by changing the L, Y ₂ , Y ₃ , X ₁ and the type of curve (ellipse, hyperbola, etc.) at the tips of the bent protrusions 41 and 42 . The shapes of the tips of the bent protrusions 41 and 42 can be varied in various ways, as shown in FIGS. 26 and 27. The tip shapes in Figures 26 and 27 are 1 to 3.
It is a combination of two curved lines or straight lines, and is symmetrical. The configuration of the fifth embodiment other than the protrusions 41 and 42 is the same as the deflection magnifying lens 12b of the third embodiment shown in FIGS. 15 to 20.

[Sixth Embodiment] A deflection magnifying lens 12e of a sixth embodiment shown in FIG. 28 has a pair of tongue-like portions 25, 26 with bent protrusions 41, 42 at their tips. The structure other than the bent protrusions 41 and 42 is the 21st
This is the same as the deflection magnifying lens 12c of the fourth embodiment shown in FIGS.

[Modified example]

The present invention is not limited to the above-described embodiments, but can be modified, for example, as follows.

(1) As a modification of FIG. 28, the deflection magnifying lens 12f may be configured as shown in FIG. 29. In this deflection magnifying lens 12f, in order to adjust pattern distortion, the pattern of the notch on the side surface 23 of the first cylindrical electrode 18, that is, the pattern of the screen side end 23a, is a combination of a plurality of quadratic curves. Tongue-shaped portion 3 on the side surface of the second cylindrical electrode 19
6 patterns are formed so as to follow the screen side end portion 23a. The surfaces corresponding to the side surfaces 24 and 30 in FIG. 28 that are not shown in the drawings are also
It is formed the same as the side surfaces 23 and 29 in FIG. In FIG. 29, the protruding portion 41 is formed by a bent portion, but instead, the protruding portion may be provided on the opposite side by a recessed portion formed by a brace as shown in FIG. 21. In addition, the second
9, the tongues 25, 26 are shown on the second pair of surfaces 2.
3 and 24 protrude toward the screen.

(2) As shown in FIG. 30, the pattern of the end portions 23a, 29a of the side surfaces 23, 29 of the deflection magnifying lens 12g may be a combination of curved lines and straight lines. Third
Although the protrusions 41 and 42 are formed by bending in FIG. 0, they may be formed as shown in FIG.

(3) Polarizing magnifying lens 1 of the first embodiment shown in FIGS. 2 to 10 and the second embodiment shown in FIGS. 11 to 14
The protruding portions 41 and 42 of 2 and 12a may be formed by bending portions as in the fifth embodiment shown in FIG. 23 or the sixth embodiment shown in FIG. 28. In other words, the polarizing magnifying lens 1 of the fifth and sixth embodiments
2d, 12e first to fourth pair of surfaces 21 to 2
4, 27 to 30 may be curved so as to protrude in the tube axis direction.

(4) It is also applicable to a CRT having a configuration in which some or all of the quadrupole lenses 7, 8, and 10 shown in FIG. 1 are omitted.

(6) The protrusions 41 and 42 of each embodiment are
26, and this is made of a member different from the tongue part 2.
5, 26 may be electrically and mechanically coupled.

(6) The second cylindrical electrode 19 may be configured to apply a different voltage to that applied to the second acceleration electrode 17.

(7) In FIGS. 2 and 11, the entire surfaces of the first and second cylindrical electrodes 18 and 19 are bent into a hyperbolic shape, but the central portions that intersect the y-z plane and the x-z plane It is also possible to add curvature to only the corners and make the vicinity of the corners flat. Further, the angle of each electrode 18, 19 may be rounded. Further, the cross-sectional shape of each surface may be a curve such as a circle, an ellipse, or a parabola.

(8) It is also applicable to a storage tube that targets the screen 13. Therefore, in the present invention, the screen also includes the target.

〔Effect of the invention〕

As is clear from the above, according to the present invention, with a relatively simple structure of providing a protrusion on the tongue-shaped portion,
Deflection sensitivity can be increased.

[Brief explanation of drawings]

FIG. 1 shows a CRT according to the first embodiment of the present invention.
2 is a perspective view showing the deflection magnifying lens of the first embodiment, FIG. 3 is a perspective view showing the first cylindrical electrode of FIG. 2, and FIG. 4 is a perspective view of the first cylindrical electrode of FIG. FIG. 5 is a side view of the deflection magnifying lens shown in FIG. 2, FIG. 6 is a sectional view taken along the - line in FIG.
Figure 7 is a cross-sectional view taken along the line - in Figure 5 and a diagram showing the beam trajectory, Figure 8 is a diagram showing a cross-sectional view taken along the line - in Figure 4 and the beam trajectory, and Figures 9 and 10 are patterns of protrusions. 11 is a perspective view showing the deflection magnifying lens of the second embodiment. FIG. 12 is a sectional view of a portion corresponding to line XII-XII in FIG. 13.
Figure 3 is a plan view of the deflection magnifying lens in Figure 11;
Figure 4 is a side view of the deflection magnifying lens in Figure 11;
5 is a perspective view showing the deflection magnifying lens of the third embodiment, FIG. 16 is a perspective view showing the first cylindrical electrode of FIG. 15, and FIG. 17 is a front view of the deflection magnifying lens of FIG. 15. , FIG. 18 is a plan view of the deflection magnifying lens in FIG. 15, FIG. 19 is a side view of the deflection magnifying lens in FIG. FIG. 22 is a sectional view of the tongue-shaped portion of the deflection magnifying lens of FIG. 21; FIG. 23 is a perspective view of the deflection magnifying lens of the fifth embodiment; 24 is a perspective view showing the first cylindrical electrode in FIG. 23;
The figures are a side view of the first cylindrical electrode in Fig. 23 and a side view of the first cylindrical electrode in Fig. 26.
27 and 27 are diagrams showing the deformation of the protrusion by the portion corresponding to the - line in FIG. 25, FIG. 28 is a perspective view showing the deflection magnifying lens of the sixth embodiment, and FIGS. FIG. 30 is a side view showing a modified example of a deflection magnifying lens. 18... First cylindrical electrode, 19... Second cylindrical electrode, 21, 22... First pair of surfaces, 23, 24... Second pair of surfaces, 25, 26... Tongue-shaped portion, 27, 28...
Third pair of surfaces, 29, 30...Fourth pair of surfaces, 4
1, 42...Protrusion.

Claims (1)

[Claims] 1. An electron gun, a first deflection system that deflects an electron beam emitted from the electron gun in a first direction, and a second deflection system that deflects the electron beam in a second direction orthogonal to the first direction. a second deflection system that deflects the deflection means;
It comprises at least a screen that impacts the electron beam emitted from the electron gun, and a deflection magnification electron lens disposed between the deflection means and the screen, the deflection magnification electron lens being coaxially arranged. The first cylindrical electrode 18 is configured such that the first direction is the y-axis, the second direction is the x-axis, and the electrons in the non-deflected state are When the traveling direction of the beam is the z-axis, x-z
a first pair of surfaces 21 arranged symmetrically around the surface;
22, and a second symmetrically arranged around the y-z plane.
The second cylindrical electrode 19 has a third pair of surfaces 27, 28 arranged symmetrically about the x-z plane, and a y-z plane.
a fourth pair of surfaces 29 arranged symmetrically about the z-plane;
30, a pair of tongues 25 and 26 are provided on the first pair of surfaces 21 and 22 that protrude in the screen direction, and the tongues 25 and 26 are provided on both sides of a space where the pair of tongues 25 and 26 face each other. The first and second cylindrical electrodes 18 and 19 are arranged so that the fourth pair of surfaces 29 and 30 are located, and the electron beam deflected in the first direction by the first deflection system is The direction of movement is reversed by the quadrupole lens constituted by the first and second cylindrical electrodes 18 and 19 to produce an effect of expanding the deflection, and the second direction is caused by the second deflection system. A cathode ray tube is provided with potential applying means for applying a potential to the first and second cylindrical electrodes 18 and 19 so as to cause the electron beam swung to be deflected and expanded by the quadrupole lens. In the x-z plane, the protrusions 41 and 42, which extend in the x-axis direction, protrude in a direction that narrows the opposing distance between the pair of tongues 25 and 26, and are opposed to each other, are connected to the pair of tongues 25, 26, A cathode ray tube characterized in that the projections 41 and 42 are provided in a part of the tube 26 to strengthen the deflection and amplification effect in the x-axis direction and the y-axis direction. 2. The method according to claim 1, wherein the second cylindrical electrode 19 is arranged to surround at least one pair of tongues 25 and 26 of the first cylindrical electrode 18. cathode ray tube. 3. The fourth pair of surfaces 29, 30 include a pair of tongues 36, 37 that protrude toward the electron gun, and the first pair of surfaces 21, 22 have a pair of tongues 2.
The fourth pair of surfaces 2 are located on both sides of the opposing spaces 5 and 26.
2. A cathode ray tube according to claim 1, characterized in that nine and thirty pairs of tongue-shaped portions are arranged. 4. The cathode ray tube according to claim 1, 2, or 3, wherein the protrusions 41, 42 are protrusions provided in a band shape extending in the x-axis direction. 5 The protruding portions 41 and 42 are connected to the pair of tongue-like portions 2.
The cathode ray tube according to claim 1, 2 or 3, wherein the cathode ray tube is a bent portion provided at the tip of the cathode ray tube.