KR20000048174A - Color cathode­ray tube apparatus - Google Patents

Abstract

PURPOSE: A color cathode ray tube is provided to prevent a deterioration of focusing characteristics in case of either shortening the total length of the tube or flattening a screen. CONSTITUTION: A color cathode ray tube includes a deflection yoke(14) which is equipped outside a funnel(11) and generates a deflected magnetic field deflecting three electron beams(18B,18R,18G) in directions of first and second axes(H,V). The deflection yoke(14) reduces an unbalanced component of the magnetic field deteriorating a beam spot on a fluorescent screen(15) with respect to the deflected magnetic field in the direction of the first axis(H), and further, corrects image distortion and convergence with respect to the deflected magnetic field in the direction of the second axis(V). In particular, the color cathode ray tube further includes a convergence correcting coil disposed between a cathode of an electron gun(19) and a center of the deflection yoke(14). The convergence correcting coil makes a displacement of a pair of side beams(18B,18R) to become relatively distant from a center beam(18G).

Description

Color cathode ray tube device {COLOR CATHODEORRAY TUBE APPARATUS}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to color cathode ray tube devices such as TV cathode ray tubes, monitor cathode ray tubes, and the like. In particular, high quality TVs and high-resolution monitors have a color cathode ray that can prevent deterioration of focus characteristics even when the screen is flattened or shortened. Relates to a tube device.

In general, a color cathode ray tube device has a vacuum outer container in which a display portion is composed of a rectangular panel, a funnel connected to the panel, and a cylindrical neck connected to the small diameter end of the funnel. On the inner surface of the panel, a phosphor screen having a dot or stripe-like three-color phosphor layer emitting blue, green, or red light is provided. In addition, the shadow screen is opposed to the phosphor screen through a gap on the inner surface thereof, and the shadow mask is arranged in the panel. The shadow mask is formed with a plurality of holes through which an electron beam having a color discrimination function for landing the electron beam on the corresponding three-color phosphor layer and emitting the corresponding three-color phosphor layer. Moreover, the electron gun apparatus which emits three electron beams is accommodated in the neck. Also, a deflection yoke is attached to the neck so as to surround the outside of the small diameter portion of the funnel. The three electron beams emitted from the electron gun are deflected by a deflection magnetic field in which a deflection yoke is generated, and are directed to a phosphor screen through a shadow mask, and the phosphor screen is horizontally scanned at a high frequency period by an electron beam and is vertically scanned at a low frequency period. By doing so, a color image is displayed on the screen.

In such a color cathode ray tube device, it is necessary to satisfy the so-called convergence characteristic in which three electron beams are concentrated at about one point on the phosphor screen. In this convergence characteristic, in the early color cathode ray tube apparatus, the error in which three electron beams do not concentrate on one point, that is, the convergence error is decomposed into a plurality of error patterns derived from the geometric relationship between the three electron beams and the phosphor screen, and is deflected. A satisfactory convergence characteristic can be obtained by supplying a convergence correction current for correcting each error pattern to the converged yoke mounted on the neck side of the yoke. Therefore, in the early color cathode ray tube devices (so-called color cathode ray tube devices of the converged yoke correction type), a convergence correction current having a plurality of special waveforms applied to the deflection current is generated in the drive circuit, and the drive circuit generates a convergence yoke. It was necessary to supply the correction current.

However, in-line self-convergence type color cathode ray tube devices that do not require the supply of convergence correction current have emerged, and have been replaced by earlier convergence yoke correction type color cathode ray tube devices. . This inline self-convergence type color cathode ray tube device has an inline structure in which the electron gun device emits three electron beams in a row arranged by a center beam and a pair of side beams passing through the same horizontal plane. In this in-line device, the horizontal deflection magnetic field in which the deflection yoke is generated is formed in a pincushion type, and the vertical deflection magnetic field is formed in a barrel shape, and these non-uniform horizontal and vertical deflection magnetic fields do not require special correction means. Good convergence characteristics are realized throughout.

However, in this in-line self-convergence type color cathode ray tube apparatus, deformation of the deflected electron beam occurs due to non-uniformity of the deflection magnetic field, and in particular, beam spots around the screen are deformed to the horizontal length, which may cause deterioration or unevenness of the resolution.

However, in recent years, color cathode ray tube devices have been strongly required to improve resolution, large screen, shorten tube length due to wide-angle deflection, and flatten screen. Inline and self-convergence type color cathode ray tube devices that meet these demands require more stringent focus performance, requiring a strong non-uniform deflection magnetic field that concentrates three electron beams across the screen. Therefore, in such a color cathode ray tube apparatus, the beam spot formed around the screen is more strongly deformed. In addition, since the electron beam toward the periphery of the screen is incident on the phosphor screen at a large incident angle, deformation of the beam spot is further enhanced.

In the color cathode ray tube where PCM1 (Purity, Convergence, Magnet) is installed around the neck, three electron beams (3B, 3G, 3R) are concentrated at the center (O) of the phosphor screen (2) by adjusting this PCM1. do. However, in such a color cathode ray tube, as shown in FIG. 1, the path length of the three electron beams 3B, 3G, and 3R becomes long in the periphery P of the phosphor screen 2, resulting in a broken line. The pair of side beams 3B and 3R shown are overconverged so that they do not enter the point P. FIG.

To correct this overconvergence, as shown in Fig. 2A, when the horizontal deflection magnetic field 5H, in which the horizontal deflection coil 4H is generated, is pincushioned, the electron beam is deflected to the right from the electron gun apparatus toward the phosphor screen. Electron beams 3B, 3G and 3R are subjected to forces F HB, F HG and F HR from the horizontal deflection field 5H. This force (F HB, F HG, F HR) is

F HB〉 F HG〉 F HR

And the pair of side beams 3B and 3R are displaced in the direction away from the center beam 3G in the horizontal direction (H axis direction) by the forces F HB, F HG and F HR. . In other words, these forces F HB, F HG and F HR impart an underconvergence to the electron beam. Similarly, in order to correct overconvergence, as shown in Fig. 2B, when the vertical deflection field 5V in which the vertical deflection coil 4V is generated is formed in a barrel shape, a pair of side beams 3B are formed from the vertical deflection field 5V. , 3R) are applied to the force (F VB, F VR), the force ((F VB, F VR) includes a component that displaces the electron beam in a direction away from each other in the horizontal direction, the electron beam Thus, the degree of non-uniformity of these horizontal and vertical deflection magnetic fields 5H, 5V is adjusted so that the three electron beams 3B, 3G, 3R around the screen P as shown by the solid line in FIG. This is concentrated.

However, when the horizontal and vertical deflection magnetic fields 5H and 5V are set to the above non-uniform deflection magnetic field, the forces shown by arrows 6a and 6b in FIG. 3 act on the three electron beams 3B, 3G and 3R. Each of the electron beams 3B, 3G, and 3R is subjected to a lens action that diverges in the horizontal direction and focuses in the vertical direction (V-axis direction).

4 is a view for explaining the action of the lens formed by the electron gun and the deflecting magnetic field acting on the electron beam, the upper side of the tube axis (Z) shows the effect of the vertical direction applied to the electron beam, the lower side the action of the horizontal direction Indicates. 4, the broken line shows the trajectory of the electron beam 3 toward the center of the phosphor screen 2, and the solid line shows the trajectory of the electron beam 3 toward the periphery. The symbol DL is a lens formed by the deflection magnetic field, the symbol ML is a main lens focusing (focusing) the electron beam 3 formed between the electrodes of the electron gun, and the symbol QL is a lens of the main lens. It is an auxiliary lens that best fits the focus condition at each point on the phosphor screen 2 by using a voltage which is formed between the electrodes in the vicinity and dynamically varies. The auxiliary lens QL mainly compensates for image curvature aberration caused by the difference in the path length of the electron beam 3 and astigmatism caused by the lens DL. In the drawings, the difference in the path length is omitted for simplicity, and is shown as an astigmatism lens having a function of compensating the action of the lens DL in the periphery of the phosphor screen 2.

In such a lens system, since the lens DL and the auxiliary lens QL are not formed when the electron beam 3 is directed toward the center of the phosphor screen 2, the lens magnifications in the horizontal and vertical directions are the same and the lines 7 are on the line 7. A round water point is formed on the phosphor screen 2 to connect a round shop. However, the electron beam 3 directed toward the periphery of the phosphor screen 2 diverges in the vertical direction and in the horizontal direction by the lens DL at a position far away from the main lens ML in the direction of the phosphor screen 2. The action is imparted, and the astigmatism imparted to the electron beam imparted to the lens DL is compensated by the auxiliary lens QL formed in the vicinity of the main lens ML. For this reason, the magnification of the combined lens combining these lenses DL, QL and ML is reduced in the vertical direction, unlike the magnification of only the main lens ML, so that the vertical diameter of the beam spot on the phosphor screen 2 is reduced. The horizontal diameter of the beam spot on the phosphor screen 2 is increased. As a result, a shop deformed in the horizontal direction on the phosphor screen 2 is connected to the round point on the line 7.

This problem cannot be ignored as the flattening and / or high resolution of the screen has recently progressed. In particular, the radius of curvature of the panel, which is approximated by a drop in the neck (difference in position) along the tube axis between the center of the panel and the diagonal end, is more than twice the diagonal effective diameter of the phosphor screen, and the phosphor screen forms a curved surface. This problem has been one of the most important problems of focus characteristics since the color cathode ray tube device is realized in which the focus voltage is changed so that the top surface aberration and astigmatism caused by the deflection field are corrected at the front of the screen. It is.

A method for solving the deformation of the beam spot by the non-uniform deflection magnetic field as described above is disclosed in the following documents A, B, C and the like. These documents disclose a technique in which the horizontal and vertical deflection magnetic fields are equalized, and the overconvergence at the horizontal and vertical ends caused by the uniformity is corrected by the convergence correction means arranged on the neck side rather than the center of the deflection yoke.

Document A: “A NEW HIGH-RESOLUTION TRINITRON COLOR PICTURE FOR DISPLAY APPLICATION” IEEE TRANS.CONSUMER ELECTRON CE-26 PP466-471, 1980.

Document B: “THE SSC DEFLECTION YOKE FOR IN-LINE COLOR CRT'S” PROC.OF THE SID.VOL. 30/1, PP29-32, 1989.

Document C: “A NEW PICTURE TUBE SYSTEM WITH HOMOGENEOUS SPOT PERFORMANCE” PROC.OF JPN DISPLAY′89, PP458-461,1989.

The action of the lens imparted to the electron beam by the uniform deflection magnetic field and convergence correction means of these documents is shown in FIG. The upper side of the tube axis shows the vertical action applied to the electron beam, and the lower side shows the horizontal action. The broken line shows the center of the phosphor screen 2, and the solid line shows the trajectory of the electron beam 3 toward the periphery. In the lens system shown in FIG. 5, since the horizontal and vertical deflection magnetic fields are uniform magnetic fields, the lens DL generated by the deflection magnetic field of the conventional color cathode ray tube apparatus shown in FIG. 4 is not formed. The lens CL is formed to act on the electron beam to become the main lens ML, the auxiliary lens QL, and the lens CL by the convergence correction means.

The lens CL is characterized in accordance with the structure of the convergence correction means, but basically acts on the electron beam to generate astigmatism similar to the lens DL. For example, Document B discloses a structure for generating a magnetic field for correcting convergence. However, since a magnetic body forming a locally uniform magnetic field is used in a region to which the correction magnetic field is applied, the effect of astigmatism is eliminated. have. However, this lens CL is ideally formed near the auxiliary lens QL between the cathode of the electron gun and the center of the deflection yoke, and the distance between the auxiliary lens QL compared to the conventional lens DL. Is significantly smaller. Therefore, even if CL has astigmatism, the magnification of the combined lens combining the lenses ML, QL, and CL hardly changes. As a result, the horizontal deformation of the beam spot is improved, and the resolution and the like are improved.

Further, the conventional convergence correction means disclosed in the documents B and C is composed of a convergence correction coil and a current supply means for supplying the convergence correction coil with a parabolic shape correction current which varies in synchronization with horizontal and vertical deflections. In particular, the document B is provided with an electric circuit composed of a resistor, a capacitor, and the like on the deflection yoke and discloses a means for generating a parabolic shape correction current directly from the deflection current or the deflection voltage. However, if the parabolic shape correction current is to be generated directly on the deflection yoke, the simple circuit disclosed in this document makes it difficult to obtain an ideal waveform that is symmetrical and secondarily variable, and rather, the design of the deflection yoke is burdensome. There is a problem. Further, in the current supply means for supplying the correction current from the drive circuit side, there is a problem that the burden on the drive circuit side becomes large.

As described above, the color cathode ray tube device is currently configured in an inline type to emit three electron beams in a row arranged by a center beam and a side beam through which an electron gun passes on the same horizontal plane, and a horizontal deflection magnetic field generated by the deflection yoke is a pincushion type. The vertical deflection field is determined in a barrel shape, and an inline / sense convergence type color cathode ray tube device in which three electron beams in a row are deflected by these horizontal and vertical deflection fields is widely used. However, in this in-line self-convergence type color cathode ray tube device, there is a problem that deformation occurs in the beam spot due to a non-uniform deflection magnetic field, and in particular, the resolution deteriorates around the screen.

In addition, when the convergence correction means is provided, there is a problem that the burden of the current supply circuit for supplying the convergence correction current to the convergence correction coil, scattering of the convergence correction current waveform, and the like occur.

SUMMARY OF THE INVENTION An object of the present invention is to provide a color cathode ray tube device capable of obtaining a good beam spot with little deformation over the entire surface of the screen without causing any problem even if the entire length of the tube is shortened or the screen is flattened.

1 is a view for explaining the convergence of three electron beams at the center and corners of a phosphor screen of a conventional color cathode ray tube device;

2A is a view showing a horizontal deflection magnetic field in which a deflection yoke of a conventional color cathode ray tube device is generated;

2B is a view showing a vertical deflection magnetic field in which a deflection yoke of a conventional color cathode ray tube is generated;

3 is a view for explaining the force on the electron beam of the deflection magnetic field of the conventional color cathode ray tube device,

4 is a view for explaining the lens action of the deflection magnetic field on the electron beam of the conventional color cathode ray tube device;

5 is a view for explaining the lens action of the convergence correction means of the conventional color cathode ray tube device to the electron beam;

6 is a view showing the configuration of a color cathode ray tube device according to one embodiment of the present invention;

FIG. 7 illustrates a horizontal deflection magnetic field in which a deflection yoke of the color cathode ray tube device shown in FIG. 6 is generated;

FIG. 8 is a view showing image deformation occurring when the horizontal deflection magnetic field of the deflection yoke shown in FIG. 7 is weakened;

9 is a view for explaining a method of adjusting the convergence of three electron beams at the center and left and right ends of the phosphor screen of the color cathode ray tube device shown in FIG. 6;

10 is a view showing the shape of the beam spot of the color cathode ray tube device shown in FIG.

11 is a perspective view schematically showing a structure of a deflection yoke installed in a color cathode ray tube device as a convergence correction means according to a first embodiment of the present invention;

12 is a diagram showing the configuration of a current supply circuit for supplying current to a convergence correction coil, which is the convergence correction means shown in FIG. 11;

FIG. 13 is a diagram showing the configuration of a parabolic waveform voltage forming circuit for supplying a parabola waveform voltage to the current supply circuit shown in FIG. 12; FIG.

FIG. 14 is a diagram showing a configuration of a power supply unit supplying a DC voltage to the current supply circuit shown in FIG. 12;

15 is a cross-sectional view schematically showing the structure of a convergence correction coil installed in a deflection yoke according to a second embodiment of the present invention;

16 is a perspective view schematically showing the structure of a convergence correction coil according to a second embodiment of the present invention;

17A is a cross-sectional view schematically showing the structure of a convergence correction coil installed in a deflection yoke according to a third embodiment of the present invention;

17B is a diagram illustrating a circuit configuration of supplying current to the convergence correction coil shown in FIG. 17A.

* Explanation of symbols for the main parts of the drawings

10: Panel 11: Funnel

12: neck 13: small diameter

14: deflection yoke 15: phosphor screen

18B, 18R: pair of side beams 18C: center beam

19: electron gun 25: convergence correction means

36a, 36b, 36c, 36d: convergence correction coil 37: (convergence correction) current supply circuit

43: parabolic waveform voltage forming circuit 56: power supply

(1) According to the present invention

A rectangular panel having a first axis and a second axis that intersect the tube axis and are orthogonal to each other, and has a phosphor screen on the inner surface thereof, a funnel-shaped funnel connected to the panel, and a neck installed next to the small diameter end of the funnel; A vacuum appearance vessel having a flatness in which the radius of curvature of the panel is approximated twice the effective diameter of the phosphor screen based on the drop from the center of the panel to the neck side from the center of the tube to the diagonal end;

An inline electron gun having a cathode and a plurality of electrodes provided in the neck and emitting three electron beams in a row arrangement consisting of a center beam and a pair of side beams arranged in a first axis direction;

A deflection yoke mounted from the neck over the outside of the small diameter portion of the funnel and generating a deflection magnetic field that deflects three electron beams in the first and second axial directions, mainly on the phosphor screen for the first axial deflection magnetic field. A deflection yoke for reducing the non-uniform magnetic field deteriorating the beam spot and correcting image distortion and convergence in the direction along the first axis mainly away from the first axis for the deflection magnetic field in the second axis direction;

A convergence correction means for displacing a pair of side beams relatively away from the center beam relative to the center of the phosphor screen only in the direction along the first axis mainly from the cathode of the electron gun to the center of the deflection yoke. A color cathode ray tube device is provided.

(2) According to the present invention

A rectangular panel having a first axis and a second axis that intersect the tube axis and orthogonal to each other, having a phosphor screen on an inner surface thereof, a funnel-shaped funnel connected to the panel, and a neck connected to the small diameter end of the funnel; A vacuum appearance vessel having a flatness whose panel radius of curvature is approximated to the effective diameter of the panel at least two times the diagonal effective diameter of the phosphor screen based on the drop from the center of the panel to the neck side from the center of the tube to the diagonal end;

An inline electron gun having a cathode and a plurality of electrodes provided in the neck and emitting three electron beams in a row arrangement consisting of a center beam and a pair of side beams arranged in a first axis direction;

A deflection yoke mounted from the neck over the outer side of the small diameter portion of the funnel and generating a deflection magnetic field that deflects three electron beams in the first and second axial directions, wherein the deflection magnetic field in the first or second axis direction is the above-mentioned. Deflection yoke to reduce non-uniform magnetic field deterioration of the beam spot on the phosphor screen and

The center beam relative to the center of the phosphor screen relative to the center of the phosphor screen in a direction along at least one of the first and second axes between the cathode of the electron gun and the center of the deflection yoke; A convergence correcting means for displacing in a direction away from the data, wherein the convergence correcting means includes a coil for generating a convergence correction magnetic field and a current supply circuit for supplying a convergence correction current to the coil, the current supply circuit including at least the convergence correction means; There is provided a color cathode ray tube device having an amplification circuit portion for outputting a convergence correction current of the same waveform to the coil by an input voltage having the same waveform as a magnetic field, and having convergence correction means mounted on the color cathode ray tube device.

(3) According to the present invention, in the color cathode ray tube device according to (2), the electron gun includes an electrode forming a main lens, and the electrode is formed in at least one of the first axis and the second axis of the deflection yoke. A parabolic waveform voltage fluctuating in synchronization with a deflection is applied, and a color cathode ray tube device is provided in which the input voltage to the amplifying circuit portion is a voltage dedicated to the parabolic waveform voltage.

(4) According to the present invention, in the color cathode ray tube device according to (2), there is provided a color cathode ray tube device in which the input voltage to the amplifier circuit portion is a voltage obtained by smoothing the high frequency fluctuation component of the input voltage in the vertical return period.

(5) According to the present invention, in the color cathode ray tube device according to (2), the convergence correction means includes a voltage forming circuit portion which electrically forms an input voltage to the amplifying circuit portion from a deflection voltage or deflection current of the deflection yoke. There is provided a color cathode ray tube device, wherein the voltage forming circuit portion is mounted on the color cathode ray tube device.

(6) According to the present invention, in the color cathode ray tube device according to (2), the power supply unit further includes a power source for operating the amplification circuit portion by electrically processing the deflection voltage of the deflection yoke, and the power supply unit is mounted in the color cathode ray tube device. A color cathode ray tube device is provided.

(7) According to the present invention

A rectangular panel having a first axis and a second axis that intersect the tube axis and orthogonal to each other, having a phosphor screen on an inner surface thereof, a funnel-shaped funnel connected to the panel, and a neck connected to the small diameter end of the funnel; A vacuum appearance vessel having a flatness whose panel radius of curvature is approximated to the effective diameter of the panel at least two times the diagonal effective diameter of the phosphor screen based on the drop from the center of the panel to the neck side from the center of the tube to the diagonal end;

An inline electron gun having a cathode and a plurality of electrodes provided in the neck and emitting three electron beams in a row arrangement consisting of a center beam and a pair of side beams arranged in a first axis direction;

A deflection yoke mounted from the neck over the outer side of the small diameter portion of the funnel and generating a deflection magnetic field that deflects three electron beams in the first and second axial directions, wherein the deflection magnetic field in the first or second axis direction is the above-mentioned. Deflection yoke to reduce non-uniform magnetic field deterioration of the beam spot on the phosphor screen and

The center beam relative to the center of the phosphor screen relative to the center of the phosphor screen in a direction along at least one of the first and second axes between the cathode of the electron gun and the center of the deflection yoke; A convergence correcting means for displacing in a direction away from the apparatus, wherein the convergence correcting means comprises a coil for generating a convergence correction magnetic field and a current supply circuit for supplying a convergence correction current to the coil; There is provided a color cathode ray tube device having convergence correction means for performing convergence correction by differentially shifting the symmetry of convergence with respect to two axes.

(Example)

Hereinafter, a color cathode ray tube device according to an embodiment of the present invention with reference to the drawings.

6 schematically shows a basic structure of a color cathode ray tube device according to an embodiment of the present invention. This color cathode ray tube device comprises a vacuum outer container, and the vacuum outer container is a horizontal axis intersecting the tube axis (Z axis) and perpendicular to each other, that is, the first axis (H axis) and the vertical axis, that is, the second axis (V axis). Panel 10 having a rectangular shape, having a funnel-shaped funnel 11 connected to the panel 10, and a cylindrical neck 12 connected to the small diameter end of the funnel 11; ) Is a phosphor whose radius of curvature of the panel 10 perspectively approximated by a drop (distance difference along the tube axis) toward the neck 12 along the tube axis (Z axis) between the center of the panel 10 and the diagonal end is described later. It has a flatness determined to be more than twice the diagonal effective diameter of the screen. A deflection yoke 14 is mounted across the small diameter portion 13 of the funnel 11 on the side of the funnel 11 of the neck 12. On the inner surface of the panel 10, there is provided a phosphor screen 15 having a dot- or stripe-shaped three-color phosphor layer (stripe in the example shown) that emits blue, green, and red light. In addition, a shadow mask 17 is disposed to face each other with a gap between the phosphor screens 15, and the shadow mask allows a passage of an electron beam to the opposite surface to be landed on a corresponding phosphor layer. A plurality of electron beam through holes 16 having a plurality of holes are formed at a predetermined arrangement pitch. In the neck 12, an electron gun device that emits three electron beams 18B, 18G, and 18R arranged in a row consisting of a center beam 18G and a pair of side beams 18B and 18R passing through the same horizontal plane. 19) is arranged. Further, a PCM (purity convergence magnet) (not shown) is attached to the outside of the neck 12 as a rear portion of the deflection yoke 14.

The electron gun device 19 has three cathodes arranged in a line in the horizontal direction, three heaters for heating these cathodes, and a plurality of electrodes arranged in the phosphor screen 15 direction at the cathode. A main lens is formed which focuses three electron beams 18B, 18G, and 18R in a row arranged toward the screen by at least a plurality of electrodes, and changes in synchronization with the deflection of the deflection yoke 14. An auxiliary lens diverges in the vertical direction by focusing and focuses in the horizontal direction.

The deflection yoke 14 generates a horizontal deflection coil for generating a horizontal deflection magnetic field for deflecting three electron beams 18B, 18G, and 18R emitted from the electron gun device 19 in a horizontal direction and a vertical deflection magnetic field for deflecting in the vertical direction. It has a vertical deflection coil. As shown in FIG. 7, the horizontal deflection magnetic field 22H in which the horizontal deflection coils 21a and 21b are generated generates a substantially uniform magnetic field. By uniformizing the horizontal deflection field as described above, the vertical component of the horizontal deflection field that acts in the direction of disturbing the vertical deflection with respect to the electron beam directed toward the diagonal end of the phosphor screen is reduced as compared with the conventional pincushion type horizontal deflection field. As described above, the upper and lower ends of the screen 24 deform into a pincushion type. Therefore, in order to correct such pincushion-like image distortion, the deflection yoke 14 is provided with distortion correction means (not shown) made of one set of NS magnets, and the function of correcting this distortion is enhanced. On the other hand, the vertical deflection magnetic field in which the vertical deflection coils are generated is determined to be barrel-shaped, and the barrel-type magnetic field is strengthened, and the over-convergence at the upper and lower ends of the screen 24 due to the enhancement of the deformation correction function is the barrel type. It is compensated by underconvergence by the vertical deflection field.

That is, in the deflection meter of one embodiment of the present invention, pincushion-type image distortion is corrected in a state where convergence at the upper and lower ends of the screen 24 is satisfied.

In addition, in the color cathode ray tube device according to the embodiment of the present invention, three electron beams 18B, 18G, and 18R are disposed between the cathode of the electron gun 19 and the center of the deflection yoke 14. Magnetically or electrically operative to move (under convergence) the pair of side beams 18B, 18R away from the center beam 18G in the direction of the arrangement of the three electron beams 18B, 18G, 18R when directed toward the horizontal direction of the Convergence correction means (not shown) consisting of means is provided.

When the horizontal deflection magnetic field 22H in which the horizontal deflection coils 21a and 21b are generated as described above is a uniform magnetic field, three electron beams 18B, 18G, and 18R are generated from the horizontal deflection magnetic field 22H as shown in FIG. The forces received (F HB, F BG, F HR) are equal.

In the conventional color cathode ray tube apparatus, as shown by a broken line in FIG. 1, overconvergence is achieved at the left and right ends of the phosphor screen. However, in this embodiment, since the convergence correction means is provided, the phosphor screen 15 is shown in FIG. Forces F SB and F SR from the convergence correction means 25 are applied to the pair of side beams 18B and 18R at the left and right ends P of the to compensate for the over convergence caused by the horizontal deflection magnetic field being a uniform magnetic field. The three electron beams 18B, 18G, and 18R can be matched. However, at the center O of the phosphor screen 15, the convergence correction means 25 does not operate, and the three electron beams 18B, 18G, and 18R remain in agreement. Reference numeral 26 denotes PCM.

Therefore, if the color cathode ray tube device is constituted as described above, the horizontal deformation of the beam spot is alleviated and the resolution is improved at the left and right ends of the phosphor screen 15 by the horizontal deflection field 22H as in the prior art.

On the other hand, since the vertical deflection field is in a non-uniform state (although the barrel shape is strengthened), it is conceivable that the same operation as that described in Documents A, B, and C can be expected at the upper and lower ends of the phosphor screen 15, but the electron beam ( Since the angle of incidence around the phosphor screen 15 decreases with respect to the angle of incidence of the phosphor screen 15 of 18B, 18G, and 18R, the beam spot is deformed into a shape extending in the radial direction. Therefore, at the left and right ends of the phosphor screen 15, the influence of the non-uniform deflection magnetic field on the beam spot and the effect due to the smaller angle of incidence become intensified with each other, and the deformation of the beam spot becomes longer, but the upper and lower ends The effects are the directions in which they are compensated for. Therefore, the deformation of the beam spot is alleviated and the beam spots 28B, 28G, and 28R hardly deform at the upper and lower ends of the screen 24 as shown in FIG. On the contrary, in terms of the vertical deflection, there is a slight vertical deformation due to the strengthening of the deformation correction means having the opposite lens action from the barrel-type vertical deflection magnetic field.

In addition, if the color cathode ray tube device is constituted as described above, the convergence correction in the vertical axis direction is basically unnecessary. In this embodiment, the current supply circuit of the convergence correction means 25 is only in the horizontal axis direction, and the current supply circuit in the vertical axis direction is omitted.

In the above embodiment, the convergence correction means acting on the underconvergence at the left and right ends of the phosphor screen has been described. On the contrary, the convergence correction means may act on the overconvergence at the center of the phosphor screen. In other words, the convergence correction means may change the side beam in a direction away from the center beam when the three electron beams face the left and right ends relative to the case where the three electron beams are directed toward the center of the phosphor screen.

The horizontal deflection magnetic field is not limited to the non-uniform magnetic field, and the horizontal deflection magnetic field may be a weak pincushion type or barrel type by changing the correction amount of the convergence correction means. Thus, when the horizontal deflection field is non-uniform, for example, the horizontal deflection field is barrel-shaped, the beam spot deformed in the vertical direction by increasing the magnification of the combined lens at the left and right ends of the phosphor screen in the vertical direction and reducing it in the horizontal direction. It is also possible to compensate for the deformation of the beam spot due to the angle of incidence described above.

Fig. 11 shows a more specific knitted yoke according to an embodiment of the present invention provided with means for correcting convergence. The deflection yoke 14 shown in FIG. 11 includes a pair of vertical deflection coils 21a and 21b for deflecting the electron beam in the horizontal direction, a pair of left and right vertical deflection coils 30a and 30b for deflecting the electron beam in the vertical direction, and a magnetic material. It has a core 31. On the neck side (back side corresponding to the right side in the drawing) of the deflection yoke 14, a pair of commas wound around a magnetic core 33a, 33b having a shape in which both sides of the rod-shaped body extend at right angles. The free coils 34a and 34b are arranged so that the extended ends of the magnetic cores face each other. Further, on the phosphor screen side (all sides corresponding to the left side in the drawing) of the deflection yoke 14, a pair of rod-shaped NS magnets 35a and 35b are disposed above and below as a means for correcting the deformation given to the electron beam.

In this embodiment, coils 36a and 36b (convergence correction coils) are wound around the magnetic cores 33a and 33b of the pair of coma-free coils 34a and 34b as a means for correcting convergence. The convergence correction coils 36a and 36b are wound so that the polarity is inverted at four adjacent poles of the magnetic cores 33a and 33b, and the pair of side beams are caused by the quadrupole field generated by energization. It has the effect of overconverging or underconverging.

12 shows a convergence correction current supply circuit for supplying current to the coil as the convergence correction means. The convergence correction current supply circuit 37 includes a current output circuit section 37 for operating the convergence correction coil. The current output circuit section 37 includes an amplifying amplifier 38 and a feedback resistor 39. In addition to the supply part of the parabolic waveform voltage 40 which fluctuates with a deflection frequency, DC power supply 41a, 41b, and the earth 42, all are mounted in a color cathode ray tube apparatus.

The parabolic waveform voltage 40 generates a focus voltage which varies in synchronization with the deflection of the electron beam in a high-definition TV or a high-resolution monitor, and can use the focus voltage as the parabolic waveform voltage 40. In the current output circuit section 37, the convergence correction coil 36 (coils 36a and 36b) is arranged in series with the feedback resistor 39 between the amplifying amplifier 38 and the earth 42 to use the reference numeral "36". Is connected, and the convergence correction coil 36 side of the feedback resistor 39 is fed back to the amplifying amplifier 38. Therefore, when the parabolic waveform voltage 40 is input to the amplifying amplifier 38, the amplifying amplifier 38 operates to eliminate the difference between the voltage and the feedback voltage, and consequently the parabolic waveform voltage is supplied to the convergence correction coil 36. It operates to supply a current having the same waveform as 40.

Therefore, since the current output circuit unit only performs the operation of converting and outputting a current having the same shape by inputting the parabolic waveform voltage, the driving circuit side is the parabolic waveform voltage 40, which changes in synchronization with the deflection of the electron beam. It is only necessary to supply a dedicated focus voltage and supply DC power supplies 41a and 41b that can be used in combination with an existing DC power supply as a power source. In addition, compared with the conventional example in which the parabolic waveform current is directly formed on the deflection yoke, the parabolic waveform current close to the above can be obtained without applying any electrical burden to the voltage of the deflection meter.

In addition, although the amplification amplifier 38 is usually composed of a transistor or the like, various OP amplifiers capable of withstanding high frequency and high power have been commercially available in recent years, so that the size and cost of a circuit can be reduced by using this OP amplifier.

The current output circuit portion may cut the weakened portion of the parabolic waveform voltage 40 by using a diode or the like as the energy suppressing means and input the amplified amplifier 38. Since the weakened portion of the parabolic waveform voltage 40 is a portion that fluctuates at high frequency, the energy consumption of the amplifying amplifier 38 increases when the current waveform is followed by the voltage waveform. Therefore, the power consumption can be suppressed by cutting the portion where the parabolic waveform voltage 40 is weakened as described above and inputting the voltage of the smooth waveform, and the amplifying amplifier 38 can be constructed at low cost. In addition, since the parabolic waveform voltage 40 is weakened, since the horizontal retrace period is not displayed on the screen, there is no influence on the screen.

In addition, by inputting a superimposed DC voltage to the parabolic waveform voltage 40, it is possible to adjust the convergence of a pair of side beams in the horizontal direction over the entire screen and use it when the user adjusts the convergence.

As described above, the parabolic waveform voltage 40 having a horizontal deflection frequency can be formed from the horizontal deflection voltage or the horizontal deflection current on the deflection yoke without inputting the parabolic waveform voltage 40 from the outside. The parabolic waveform voltage forming circuit is shown in FIG. The parabolic waveform voltage forming circuit 43 has a circuit connected to the earth 42 through the capacitor 44 and the branching resistor 45 on the negative side of the horizontal deflection coils 21a and 21b. When such a circuit is provided, the serrated horizontal deflection current flowing through the horizontal deflection circuit is classified into the capacitor 44 through the dividing resistor 45 so that charges are accumulated, and the dividing resistor 45 discharges the accumulated electric charges. The parabolic waveform voltage 40 of the horizontal deflection frequency can be extracted from the side.

Even if the parabolic waveform voltage 40 is formed in this way, since the power related to the voltage-current conversion described above is supplied from an external DC power source, the deflection power is directly influenced or formed as in the conventional art of directly forming the parabolic waveform current. It does not cause a problem that disturbs the waveform of the parabolic waveform current.

In addition, the sawtooth voltage waveforms 48 are provided by resistors 46 and 47 for detecting the sawtooth voltage on the negative side of the horizontal deflection coils 21a and 21b, and the sawtooth-shaped horizontal deflection current flowing through the horizontal deflection circuit is classified. And a sawtooth voltage waveform 49 in which the voltage waveform 48 is inverted is formed, and the voltage waveforms 48 and 49 are appropriately divided by the variable resistor 50 to form a sawtooth voltage waveform. This is superimposed on the parabolic waveform voltage 40 and input to the amplifying amplifier 38 of the current output circuit portion. According to such a circuit, by adjusting the variable resistor 50, the convergence correction amount can be adjusted differentially at the left and right of the screen.

Similarly, by using the classifying resistor 45 as a variable resistor, the peak height of the parabolic waveform voltage can be adjusted, and the entire convergence correction amount can be adjusted.

As shown in Fig. 14, the AC component of the pulse-like horizontal deflection voltage is extracted from the negative side of the horizontal deflection coils 21a and 21b through the capacitor 52, and the resistors 53a and 53b and this resistance ( The DC power supply of the amplifying amplifier 38 of the amplifying amplifier 38 of the amplifying amplifier 38 of the amplifying amplifier 38 of the current output circuit part is connected by the diodes 54a and 54b and the capacitors 55a and 55b connected in series to the 53a and 53b, respectively. By supplying as 41a, 41b, this power supply part 56 can be provided on a deflection yoke, without supplying from an external DC power supply.

In this case, the electric power related to the above-described voltage-to-current conversion is also supplied from the power supply of the deflection meter, and the electric power related to the formation of the parabolic waveform current is shared with the deflection power, but no disturbance of the parabola waveform current occurs.

Therefore, the convergence correction coil is operated by this convergence correction current supply circuit, and the pincushion type of the horizontal deflection magnetic field of the deflection yoke is weakened, so that the convergence can be matched throughout the screen and the beam spot is spread over the entire surface of the phosphor screen. It is possible to improve the deformation of.

However, in this embodiment, when the pincushion type of the horizontal deflection magnetic field is weakened, the vertical component of the horizontal deflection magnetic field acting in the direction of disturbing the vertical deflection with respect to the electron beam facing the diagonal end of the phosphor screen is reduced, and the screen shown in Fig. 8 is reduced. Pincushion type deformation occurs at the upper and lower ends of (24). Therefore, in this embodiment, it is necessary to reinforce the magnetic force of the pair of NS magnets 35a and 35b shown in FIG. 11 and to reinforce the barrel type of the vertical deflection field. In this way, when the magnetic force of the pair of NS magnets is strengthened, the convergence of the side beams at the upper and lower ends of the phosphor screen acts as overconvergence. Further, when the barrel type of the vertical deflection field is strengthened, the vertical deflection field acts as underconvergence with respect to the electron beam. Accordingly, as the baller type of the NS magnet and the vertical deflection field is strengthened as described above, the deformation of the pincushion type at the upper and lower ends of the screen can be corrected while satisfying the convergence.

Therefore, by the above configuration, the convergence correction can be basically completed by the horizontal direction correction, thereby simplifying the configuration of the convergence correction means.

As a specific example, an inline self-convergence type color cathode ray tube device having a diagonal effective diameter of 46 cm and a curvature nearly three times as large as a diagonal effective diameter and having a maximum deflection angle of 100 DEG is used. It was calibrated at about 8 mm underconvergence at the left and right ends with respect to the center, and the pincushion type of the horizontal deflection magnetic field was weakened accordingly. As a result, the horizontal diameter / vertical diameter of the beam spot at the left and right ends of the phosphor screen could be improved from 0.35 to 0.55.

At the same time, it is possible to set the voltage varying dynamically to the required 600V at the left and right ends of the phosphor screen to 370V. This is because the astigmatism is also alleviated by the deformation improvement action of the beam spot. Further, by increasing the amount of convergence correction, the deformation of the beam spot can be further corrected in the longitudinal direction. In addition, the voltage fluctuating dynamically can also be finally reduced to a value necessary for correction of defocus due to image curvature aberration.

Further, in the above embodiment, since the convergence correction coil is wound around the core of the coma-free coil, the redundant component can be eliminated, and the convergence correction means can be compactly designed.

As for the convergence correction means, as shown in FIG. 15, the convergence correction coils 36a to 36b are provided on the four projections 58 protruding inward of the ring core 57, with the ferrite ring core 57 as a magnetic core. ) And a 4-pole magnetic field may be employed. In this case, four magnetic cores of the convergence correction coils 36a to 36b may be provided. However, considering the degree of freedom of the distribution of the coma-free coil serving as the combined winding, it is preferable to provide eight projections 58 as shown in the figure. Do. Specifically, the cross-sectional area of the projections 58 is 5mm x 5mm, and the convergence correction coils 36a to 36d are wound around the projections 58, so that the sensitivity of the orbital correction can be improved compared with the case where the magnetic cores made of silicon steel sheets are wound. Can be.

Such convergence correction means can increase the sensitivity of the convergence correction by increasing the cross-sectional area of the magnetic core, but inexpensive silicon steel sheet causes adverse effects such as heat generation or induction wave system caused by a horizontal deflection magnetic field that changes at high frequencies as the cross-sectional area increases. Therefore, it is effective to comprise with a high resistance material like ferrite as mentioned above.

Further, the convergence correction means is composed of four convergence correction coils 36a to 36d curved in an arc shape as shown in Fig. 16, and these four convergence correction coils 36a to 36d are deflected from the main lens of the electron gun. You may arrange | position so that the vacuum outer container to the center of a yoke may be enclosed. In such convergence correction means, by increasing the length of the magnetic path L, the convergence correction sensitivity can be improved. However, if the convergence correction coils 36a to 36d are too close to the phosphor screen side, the deformation of the beam spot, which is a conventional problem, cannot be improved. If the convergence correction coils 36a to 36d are too close to the cathode side, the trajectory of the electron beam passing through the main lens may be changed, and the beam spot may be degraded due to the spherical aberration of the lens. Therefore, ideally, the vicinity of the neck on which the deflection yoke is mounted is good.

Further, the convergence correction means is not limited to generating a four-pole magnetic field. For example, as shown in FIG. 17A, the convergence correction coil 36a is disposed on the left and right sides of the ring-shaped core 60 disposed on the neck side of the deflection yoke. 36b may be wound around the toroids, and the convergence correction coils 36a and 36b may be connected to the horizontal deflection coils 21a and 21b through the circuit shown in Fig. 17B. In this circuit, the load variable coils 63a and 63b connected to the horizontal deflection coils 21a and 21b are wound around the saturable core 62 self-biased by the magnets 61a and 61b. The condensation correction coils 36a and 36b are connected to the load variable coils 63a and 63b in parallel.

In this convergence correction means, when the horizontal deflection current flows, the load of one of the load variable coils 63a, 63b is increased and the load of the other is reduced by magnetic saturation. As a result, one magnetic field of the convergence correction coils 36a and 36b is larger than the other magnetic field at the left end of the phosphor screen, and at the right end, the magnetic field is differentially operated so that the magnitude of the magnetic field is reversed. Therefore, the convergence correction means has a configuration in which the differentially generated magnetic fields of the convergence correction coils 36a and 36b act strongly on the side beams on the side which are always deflected in the direction to assist the horizontal deflection, or the horizontal deflection Convergence of a pair of side beams can be corrected by having a structure which acts strongly with respect to the side beam on the opposite side to the side which is always deflected in the obstructing direction.

As described above, if the convergence correction means is provided between the cathode of the electron gun of the inline self-convergence-type color cathode ray tube used for high-definition television or a high-definition monitor and the center of the deflection yoke, the deformation of the beam spot is eliminated throughout the entire screen. It can be almost completely rounded. In addition, by separating the convergence correction current into a voltage / current change portion and a correction voltage generation portion, an ideal correction current waveform can be obtained and power consumption can be separated from the deflection power.

Claims (7)

A rectangular panel having a first axis and a second axis that intersect the tube axis and are orthogonal to each other, and has a phosphor screen on the inner surface thereof, a funnel-shaped funnel connected to the panel, and a neck installed next to the small diameter end of the funnel; A vacuum appearance vessel having a flatness in which the radius of curvature of the panel is approximated twice the effective diameter of the phosphor screen based on the drop from the center of the panel to the neck side from the center of the tube to the diagonal end; An inline electron gun having a cathode and a plurality of electrodes provided in the neck and emitting three electron beams in a row arrangement consisting of a center beam and a pair of side beams arranged in a first axis direction; A deflection yoke mounted from the neck over the outside of the small diameter portion of the funnel and generating a deflection magnetic field that deflects three electron beams in the first and second axial directions, mainly on the phosphor screen for the first axial deflection magnetic field. A deflection yoke for reducing the non-uniform magnetic field deteriorating the beam spot and correcting image distortion and convergence in the direction along the first axis mainly away from the first axis for the deflection magnetic field in the second axis direction; Between convergence correction means for displacing a pair of side beams relatively away from the center beam relative to the center of the phosphor screen only in a direction along the first axis between the cathode of the electron gun and the deflection yoke center; Color cathode ray tube device, characterized in that. A rectangular panel having a first axis and a second axis that intersect the tube axis and orthogonal to each other, having a phosphor screen on an inner surface thereof, a funnel-shaped funnel connected to the panel, and a neck connected to the small diameter end of the funnel; A vacuum appearance vessel having a flatness whose panel radius of curvature is approximated to the effective diameter of the panel at least two times the diagonal effective diameter of the phosphor screen based on the drop from the center of the panel to the neck side from the center of the tube to the diagonal end; An inline electron gun having a cathode and a plurality of electrodes provided in the neck and emitting three electron beams in a row arrangement consisting of a center beam and a pair of side beams arranged in a first axis direction; A deflection yoke mounted from the neck over the outer side of the small diameter portion of the funnel and generating a deflection magnetic field that deflects three electron beams in the first and second axial directions, wherein the deflection magnetic field in the first or second axis direction is the above-mentioned. Deflection yoke to reduce non-uniform magnetic field deterioration of the beam spot on the phosphor screen, and The center beam relative to the center of the phosphor screen relative to the center of the phosphor screen in a direction along at least one of the first and second axes between the cathode of the electron gun and the center of the deflection yoke; A convergence correcting means for displacing in a direction away from the data, wherein the convergence correcting means includes a coil for generating a convergence correction magnetic field and a current supply circuit for supplying a convergence correction current to the coil, the current supply circuit including at least the convergence correction means; A color cathode ray tube device comprising: an amplification circuit portion for outputting a convergence correction current of the same waveform to the coil by an input voltage having the same waveform as a magnetic field, and the amplification circuit portion including convergence correction means mounted on the color cathode ray tube device; . The method of claim 2, The electron gun includes an electrode forming a main lens, in which a parabolic waveform voltage which varies in synchronization with a deflection in at least one of the first and second axes of the deflection yoke is applied, and is input to the amplifying circuit section. A color cathode ray tube device, wherein the voltage is a voltage dedicated to the parabolic waveform voltage. The method of claim 2, A color cathode ray tube device, characterized in that the input voltage to the amplifying circuit portion is a voltage obtained by smoothing the high frequency fluctuation component of the input voltage in the vertical retrace period. The method of claim 2, The convergence correction means includes a voltage forming circuit portion for electrically forming an input voltage to the amplifying circuit portion from the deflection voltage or the deflection current of the deflection yoke, wherein the voltage forming circuit portion is mounted in the color cathode ray tube device. Color cathode ray tube device. The method of claim 2, A color cathode ray tube device, further comprising: a power supply portion for operating the amplification circuit portion by electrically processing the deflection voltage of the deflection yoke, wherein the power supply portion is mounted in the color cathode ray tube device. A rectangular panel having a first axis and a second axis that intersect the tube axis and orthogonal to each other, and having a mold-shaped screen on the inner surface thereof; a funnel-shaped funnel connected to the panel; And a vacuum appearance having a flatness in which the radius of curvature of the panel is approximated to the effective diameter of the diagonal of the phosphor screen more than twice the effective diameter of the phosphor screen based on the drop from the center of the panel to the neck side from the center to the diagonal end. Vessel, An inline electron gun having a cathode and a plurality of electrodes provided in the neck and emitting three electron beams in a row arrangement consisting of a center beam and a pair of side beams arranged in a first axis direction; A deflection yoke mounted from the neck over the outer side of the small diameter portion of the funnel and generating a deflection magnetic field that deflects three electron beams in the first and second axial directions, wherein the deflection magnetic field in the first or second axis direction is the above-mentioned. Deflection yoke to reduce non-uniform magnetic field deterioration of the beam spot on the phosphor screen, and The center beam relative to the center of the phosphor screen relative to the center of the phosphor screen in a direction along at least one of the first and second axes between the cathode of the electron gun and the center of the deflection yoke; A convergence correcting means for displacing in a direction away from the apparatus, wherein the convergence correcting means comprises a coil for generating a convergence correction magnetic field and a current supply circuit for supplying a convergence correction current to the coil; A color cathode ray tube device, characterized by comprising convergence correction means for performing convergence correction by differentially shifting the symmetry of convergence with respect to two axes.