CN1260583A

CN1260583A - Colour cathode-ray tube apparatus

Info

Publication number: CN1260583A
Application number: CN 99115984
Authority: CN
Inventors: 佐野雄一; 横田昌広; 伊吹裕昭; 森英男
Original assignee: Toshiba Corp
Current assignee: Toshiba Corp
Priority date: 1998-12-16
Filing date: 1999-12-16
Publication date: 2000-07-19
Also published as: KR20000048174A; WO2000036628A1; JP2001043815A; TW442821B

Abstract

A cathode-ray tube device comprising a deflection yoke 14 for reducing the nonuniform magnetic field component of the deflection magnetic field along a first axis which degrades the beam spot on a phosphor screen 15 and correcting the picture distortion and convergence deviating from the first axis and caused along the first axis by means of the deflection magnetic field along a second axis, and convergence correcting means 25 for shifting a pair of side beams 18B, 18R away from a center beam relatively at the peripheral part of the phosphor screen 15 only along the first axis in the course of the travel of the beams from the cathodes of electron guns to the center of the deflection yoke, whereby a good beam spot of less distortion can be formed over the screen.

Description

Color cathode-ray tube apparatus

The present invention relates to be used for television set braun tube, be used for the color cathode-ray tube apparatus of the braun tube etc. of monitor, the depth of picture planarization or shortening pipe is particularly related in high-quality television set and high-resolution monitor etc., even also can prevent the color cathode-ray tube apparatus of focus characteristics deterioration.

In general, color cathode-ray tube apparatus has vacuum casting, and this vacuum casting is that the screen dish of rectangle, the cone that is connected with this screen dish are formed with the neck cylindraceous that is connected with the small-caliber end of this cone by the display part.On the inner surface of this screen dish, configuration has the phosphor screen of the tri-color phosphor layer of the point-like of blue, green, the ruddiness of emission or strip.In addition, in this phosphor screen, the surface is upward relative with shadow mask by the gap within it, and this shadow mask is configured in the screen dish.On this shadow mask, form a plurality of holes by electron beam, this beam bombardment on the tri-color phosphor layer of correspondence, have make corresponding tri-color phosphor layer luminous select the look function.In addition, in neck, pack into and launch the electron gun arrangements of three-beam electron-beam.And, the deflection system outside the small-bore part from neck around cone is installed.Have again, be deflected the magnetic deflection field deflection that system produces from the three-beam electron-beam of above-mentioned electron gun emission, by directive phosphor screen behind the shadow mask, by this electron beam by the high frequency period horizontal sweep simultaneously by this phosphor screen of low-frequency cycle property vertical scanning, so on screen color image display.

In such color cathode-ray tube apparatus, make three-beam electron-beam focus on more roughly going up on the phosphor screen, must satisfy so-called convergence characteristics.For this convergence characteristics, in the color cathode-ray tube apparatus in early days, error on not focusing on three-beam electron-beam a bit, be that convergence errors resolves into a plurality of error figures according to three-beam electron-beam and the derivation of fluoroscopic geometrical relationship, in the convergence yoke that is installed in deflection system neck side, supply is used to proofread and correct the convergence correction electric current of each error figure, the convergence characteristics that acquisition should be satisfied.Therefore, in the color cathode-ray tube apparatus in early days (so-called convergence yoke correction type color cathode-ray tube apparatus), except that deflection current, also producing in drive circuit has the convergence correction electric current of a plurality of special waveforms, and must supply with correcting current to convergence yoke from this drive circuit.

But, the in-line self-convergent system color cathode-ray tube apparatus of convergence correction electric current has appearred not needing to supply with at present, and this device is replacing early stage convergence yoke correction type color cathode-ray tube apparatus.The electron gun arrangements of this in-line self-convergent system color cathode-ray tube apparatus has the in-line structure that be listed as the three-beam electron-beam of arrangement center electron beam and an opposite side electron beam is made of of emission by same horizontal plane.In this in-line device, the horizontal deflection magnetic field that deflection system produces forms pincushion, and that vertical deflection magnetic field forms is barrel-shaped, utilizes these level heterogeneous and vertical deflection magnetic fields, special correcting unit needn't be set, just can realize convergence characteristics good on the whole image.

But, in the color cathode-ray tube apparatus of this in-line self-convergent system, because of magnetic deflection field reason heterogeneous, in the electron beam that is deflected, produce distortion, especially the electron-beam point around the picture is flattened with growing crosswise, and definition reduces, or the danger that produces ripple is arranged.

, in recent years in color cathode-ray tube apparatus, be accompanied by promote clearness, big pictureization and wide angle deflection, the complanation of pipe total length and picture is shortened in strong request.In fully satisfying the in-line self-convergent system color cathode-ray tube apparatus of this requirement,, the strong non-homogeneous magnetic deflection field that three-beam electron-beam focuses on the whole image of making must be arranged owing to must possess stricter focus characteristics.Therefore, in such color cathode-ray tube apparatus, the electron-beam point that forms around the picture is earth deformation more.And, on phosphor screen, press big incidence angle incident owing to point to the electron beam of picture periphery, so more help the distortion of electron-beam point.

PCM1 (colour purity convergence magnet) on the neck outside is arranged in the neck color cathode-ray tube apparatus on every side, utilizes the adjustment of this PCM1, focus on three-beam electron-

beam

3B, 3G, 3R at phosphor screen 2 center O places.But in this color cathode-ray tube apparatus, as shown in Figure 1, on the periphery P of phosphor screen 2, the path of three-beam electron-

beam

3B, 3G, 3R is elongated, its result, and an opposite side electron beam 3B, 3R shown in dotted line are incident on the P by over convergence.

In order to proofread and correct this over convergence, shown in Fig. 2 A, if the horizontal deflection magnetic field 5H that horizontal deflection coil 4H is produced forms pincushion, observe from electron gun so, when electron beam directive phosphor screen during towards right side deflection, three-beam electron-

beam

3B, 3G, 3R are subjected to the effect from the power FHB of horizontal deflection magnetic field 5H, FHG, FHR.These power FHB, FHG, FHR exist

FHB(FHG(FHR

Relation, utilize this power FHB, FHG, FHR, the direction displacement that an opposite side electron beam 3B, 3R are relatively departed from from center electron beam 3G along continuous straight runs (H direction of principal axis).In other words, this power FHB, FHG, FHR produce the effect of under convergence to electron beam.Similarly, in order to proofread and correct over convergence, shown in Fig. 2 B, if the vertical deflection magnetic field 5V that frame deflector coil 4V is produced forms barrel-shaped, by this vertical deflection magnetic field 5V one opposite side electron beam 3B, 3R are produced power FVB, FVR so, this power FVB, FVR comprise make electron beam along mutually away from the composition of the direction displacement of horizontal direction, on electron beam, produce the under convergence effect.Therefore, adjust the non-uniform degree of these horizontal deflection magnetic fields 5H and vertical deflection magnetic field 5V, shown in solid line among Fig. 1, like that, three-beam electron-

beam

3B, 3G, 3R are focused on.

But, if horizontal deflection magnetic field 5H and vertical deflection magnetic field 5V are set at non-homogeneous magnetic deflection field as described above, can occur the effect of the power shown in arrow 6a, the 6b among Fig. 3 so on three-beam electron-

beam

3B, 3G, 3R, each

electron beam

3B, 3G, 3R can be subjected to dispersing in the horizontal direction and the lensing that go up to focus in vertical direction (V direction of principal axis).

Fig. 4 is the figure of explanation electron gun that above-mentioned electron beam is worked and the lensing that formed by magnetic deflection field, and at tubular axis (Z axle) upside, the effect that expression produces vertical direction to electron beam at downside, is represented the effect of horizontal direction.In Fig. 4, dotted line is represented the track towards the electron beam 3 at phosphor screen 2 centers, and solid line is represented the track towards the electron beam 3 of periphery.In addition, label DL is the lens that formed by above-mentioned magnetic deflection field, label ML is the main lens of the focused beam 3 that forms between the electrode of electron gun, and label QL is the attachment lens that makes focused condition the best of each point on the phosphor screen 2 at the voltage that utilizes dynamic change that forms between near the electrode the above-mentioned main lens.This attachment lens QL mainly contains the crooked aberration of the face that resembles that compensation produces because of the path length difference of electron beam 3 and the effect of non-some aberration producing because of lens DL, but in the drawings in order to simplify, omit path length difference, be illustrated in the non-point image aplanat that phosphor screen 2 peripheries have offset lens DL effect.

In such lens combination, at electron beam 3 during towards phosphor screen 2 central owing to do not form lens DL and attachment lens QL, thus the lens multiplying power of level and vertical direction equate, form circular object point on the line 7, on phosphor screen 2, connect circular image point.But, on the electron beam 3 of the periphery of phosphor screen 2, utilization is positioned at from main lens ML to phosphor screen the lens DL of the position that large-spacing is arranged on 2 directions, produce the effect that focuses in vertical direction and disperse on the horizontal direction, in addition, near the attachment lens QL that utilization forms main lens ML compensates the non-some aberration that produces on electron beam with lens DL.Therefore, only the multiplying power with main lens ML is different to make up the multiplying power of compound lens of these lens DL, QL, ML, dwindle in vertical direction, the vertical direction diameter of the electron-beam point on the phosphor screen 2 is reduced, increase in the horizontal direction, the horizontal direction diameter of the electron-beam point on the phosphor screen 2 is increased.Its result for the circular object point on the line 7, becomes the image point that flattens on the horizontal direction that connects on the phosphor screen 2.

Such problem is along with complanation that advances picture in recent years and high definition change into problem for not ignoring.Particularly according to the drop (alternate position spike) of the tubular axis between edge screen disk center and the diagonal angle end to the neck side, the tortuous rate radius of the screen of approximate circle reaches more than the twice of fluoroscopic diagonal angle effective diameter, and, for the focused condition of non-some aberration making correction constitute the crooked aberration of the face that resembles that curved surface produces because of phosphor screen and produce because of magnetic deflection field etc. reaches best on whole image, since realizing making the color cathode-ray tube apparatus of focus voltage change, this problem becomes a most important problem of focus characteristics.

In following document A, B, C etc., disclosed the method that solves the electron-beam point distortion that produces because of above-mentioned non-homogeneous magnetic deflection field.In these documents, disclosed level and vertical deflection magnetic field homogenizing, utilize than the convergence correction unit of the more close neck side configuration in the center of deflection system and proofread and correct because of the level of this homogenizing generation and the over convergence technology of vertical end.

Document A: " A NEW HIGH-RESOLUTION TRINITRON COLOR PICTUREFOR DISPLAY APPLICATION " IEEE TRANS.CONSUMER ELECTRON CE-26pp466 (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 HOMOGENEOUSSPOT PERFORMANCE " PROC.OF JPN DISPLAY, 89, pp458 (461,1989.

Fig. 5 represents by uniform magnetic deflection field and convergence correction unit in these documents the lensing of electron beam generation.At the tubular axis upside effect of the vertical direction that electron beam is produced is shown, in addition,, the effect of horizontal direction is shown at downside.Dotted line is represented the track towards the electron beam 3 at phosphor screen 2 centers, and solid line is represented the track towards the electron beam 3 of periphery.In lens combination shown in Figure 5, because level and vertical deflection magnetic field are uniform magnetic fields, so in color cathode-ray tube apparatus in the past shown in Figure 4, do not form the lens DL that produces by magnetic deflection field, replace this lens, utilize the convergence correction unit to form lens CL, the lens that electron beam is worked have main lens ML and attachment lens QL to reach the lens CL that is produced by the convergence correction unit.

Said lens CL is by its characteristic of structures shape of convergence correction unit, but the same with lens DL basically, resembles to produce the non-some aberration electron beam generation effect.For example, in document B, disclosed the structure that produces correct convergence magnetic field, but, do not had the effect of non-some aberration by using the magnetic that in its magnetic field for correcting zone, can form local uniform magnetic field.But these lens CL is formed on negative electrode from electron gun between the center of deflection system, is formed near the attachment lens QL more satisfactoryly, compare with in the past lens DL, and the distance between the attachment lens QL reduces significantly.Therefore, even non-some aberration effect arranged on CL, but the multiplying power of the compound lens of compound lens ML, QL, CL roughly do not change, and the result makes the flattening of the horizontal direction of electron-beam point improve raisings such as definition.

In addition, the electric current supply unit of the parabolic shape correcting current that changes synchronously by the convergence correction coil with to this convergence correction coil supply and level and vertical deflection of the unit of convergence correction in the past that discloses of document B, C constitutes.Especially in document B, disclosed the circuit that resistance and capacitor etc. are formed has been set on deflection system, utilized deflection current or deflecting voltage directly to produce the unit of parabolic shape correcting current.But, if on deflection system, directly produce such parabolic shape correcting current, in the disclosed such simple circuit of the document, be difficult to provide the ideal waveform of symmetry and secondary change so, in the design of deflection system, there is the problem of burden.In addition, supplying with the electric current supply unit of correcting current, existing the burden of drive circuit side to become big problem from the drive circuit side.

As mentioned above, in color cathode-ray tube apparatus, at present, electron gun is constituted the in-line structure of the three-beam electron-beam of emission one row configuration, this three-beam electron-beam is made up of a center electron beam and an opposite side electron beam by same horizontal plane, the horizontal deflection magnetic field that deflection system is produced is defined as pincushion, vertical deflection magnetic field is defined as barrel-shaped, utilizes in-line self-convergent system color cathode-ray tube apparatus that these levels and vertical deflection magnetic field make three-beam electron-beam deflection by extensive practicability.But, in this in-line self-convergent system color cathode-ray tube apparatus, exist because of non-homogeneous magnetic deflection field makes electron-beam point to produce distortion, particularly on the picture periphery, make the problem of definition deterioration.

And, under the situation that is provided with the convergence correction unit, exist current supply circuit to produce problems such as burden and generation convergence correction current waveform confusion to its convergence correction coil supply convergence correction electric current.

Even the object of the present invention is to provide the total length shortening of propulsion tube or the complanation of picture, do not cause the derivation problem yet, on whole image, can obtain the not color cathode-ray tube apparatus of the good electron-beam point of distortion.

(1) according to the present invention, color cathode-ray tube apparatus is provided, this color cathode-ray tube apparatus comprises:

Vacuum casting, by have intersect with tubular axis and orthogonal first with second and its inner surface is provided with fluoroscopic rectangular-shaped screen dish, the funnelform cone that is connected with the screen dish constitutes with the neck that is connected with the small-bore part end of this cone, being that the screen inner surface of benchmark has the tortuous rate radius of the screen of approximate circle is defined as flatness more than the phosphor screen diagonal angle effective diameter twice from the screen drop towards the neck side of disk center along tubular axis to the diagonal angle end

In line gun is arranged in the neck, and negative electrode and a plurality of electrode are arranged, the three-beam electron-beam that emission one row are arranged, and this three-beam electron-beam is made up of the center electron beam and the opposite side electron beam that with first direction of principal axis serve as the arrangement axle,

Deflection system, be installed in the outside of neck to the small-bore part of cone, make the deflection system of three-beam electron-beam as generation to the magnetic deflection field of first and the second direction of principal axis deflection, for the first axial magnetic deflection field, the main non-uniform magnetic-field composition that makes electron-beam point deterioration on the phosphor screen that reduces, for the second axial magnetic deflection field, main proofread and correct leave first along the first axial anamorphose and convergence and

The convergence correction unit, from the negative electrode of electron gun between the center of deflection system, mainly only along on first direction of principal axis,, make opposite side electron beam displacement relatively on away from the direction of center electron beam at its peripheral part with respect to the phosphor screen center.

(2) according to the present invention, color cathode-ray tube apparatus is provided, this color cathode-ray tube apparatus comprises:

Deflection system, be installed in the outside of neck to the small-bore part of cone, generation makes the magnetic deflection field of three-beam electron-beam along first and the second direction of principal axis deflection, the non-uniform magnetic-field composition that first or the second axial magnetic deflection field reduce to make electron-beam point deterioration on the described phosphor screen and

The convergence correction unit, from the negative electrode of electron gun between the center of deflection system, at peripheral part with respect to the phosphor screen center along at least one direction of described first and second, make opposite side electron beam displacement relatively on away from the direction of center electron beam, this convergence correction unit comprises coil that produces convergence correction magnetic field and current supply circuit from the convergence correction electric current to this coil that supply with, this current supply circuit has utilization with the input voltage of above-mentioned convergence correction magnetic field same waveform as the convergence correction electric current of same waveform as to be exported to the amplification circuits of described coil at least, and this amplification circuits is installed on the color cathode-ray tube apparatus.

(3) according to the present invention, color cathode-ray tube apparatus is provided, in (2) described color cathode-ray tube apparatus, electron gun comprises the electrode that forms main lens, on this electrode, apply along the parabolic shape waveform voltage of the synchronous change of first of deflection system and second at least one direction deflection, and the input voltage of amplification circuits is the voltage of described parabolic shape waveform voltage of migrating.

(4) according to the present invention, color cathode-ray tube apparatus is provided, in (2) described color cathode-ray tube apparatus, the input voltage of amplification circuits is the voltage of the high frequency change part of input voltage during the level and smooth vertical retrace line.

(5) according to the present invention, color cathode-ray tube apparatus is provided, in (2) described color cathode-ray tube apparatus, described convergence correction unit comprises according to the deflecting voltage of deflection system or deflection current forms voltage forming circuit part to the input voltage of amplification circuits that on circuit this voltage forming circuit partly is installed on the color cathode-ray tube apparatus.

(6) according to the present invention, color cathode-ray tube apparatus is provided, in (2) described color cathode-ray tube apparatus, also be included in the power unit that the deflecting voltage of handling deflection system on the circuit makes amplification circuits work, this power unit is installed on the color cathode-ray tube apparatus.

(7) according to the present invention, color cathode-ray tube apparatus is provided, this color cathode-ray tube apparatus comprises:

The convergence correction unit, from the negative electrode of electron gun between the center of deflection system, at peripheral part with respect to the phosphor screen center along at least one direction of described first and second, make opposite side electron beam displacement relatively on away from the direction of center electron beam, this convergence correction unit comprises the coil that produces convergence correction magnetic field and supplies with the current supply circuit of convergence correction electric current to this coil that this current supply circuit comes convergence correction with respect to described second convergence symmetry by move the position differentially.

Fig. 1 is the figure that illustrates that the three-beam electron-beam in the phosphor screen center of color cathode-ray tube apparatus in the past and bight is assembled.

Fig. 2 A is the figure of the horizontal deflection magnetic field of representing that the deflection system of color cathode-ray tube apparatus in the past produces.

Fig. 2 B is the figure of the vertical deflection magnetic field of representing that the deflection system of color cathode-ray tube apparatus in the past produces.

Fig. 3 illustrates the figure of the magnetic deflection field of color cathode-ray tube apparatus in the past to the active force of electron beam generation.

Fig. 4 illustrates the figure of the magnetic deflection field of color cathode-ray tube apparatus in the past to the lensing of the generation of electron beam.

Fig. 5 illustrates the figure of the convergence correction unit of color cathode-ray tube apparatus in the past to the lensing of electron beam generation.

Fig. 6 is the structure chart of the color cathode-ray tube apparatus of expression the present invention one example.

Fig. 7 is the figure of the horizontal deflection magnetic field that produces of the deflection system of expression color cathode-ray tube apparatus shown in Figure 6.

Fig. 8 is the die down figure of the picture distortion that produces under the situation of the horizontal deflection magnetic field that is illustrated in deflection system shown in Figure 7.

Fig. 9 be explanation color cathode-ray tube apparatus shown in Figure 6 the phosphor screen center and about the figure of convergence method of adjustment of three-beam electron-beam of end.

Figure 10 is the figure of the electron-beam point shape of expression color cathode-ray tube apparatus shown in Figure 6.

Figure 11 is a perspective view of schematically representing to be arranged on as the convergence correction unit of first embodiment of the invention the deflection system structure in the color cathode-ray tube apparatus.

Figure 12 is the figure of expression to the current supply circuit structure of the convergence correction coil supplying electric current of convergence correction unit shown in Figure 11.

Figure 13 is the parabolic waveform voltage forming circuit of parabolic waveform voltage is supplied with in expression to a current supply circuit shown in Figure 12 structure chart.

Figure 14 is the power unit of direct voltage is supplied with in expression to a current supply circuit shown in Figure 12 structure chart.

Figure 15 is a profile of schematically representing the convergence correction loop construction that is provided with in the deflection system of second embodiment of the invention.

Figure 16 is a perspective view of schematically representing the convergence correction loop construction of second embodiment of the invention.

Figure 17 A is a profile of schematically representing the convergence correction loop construction that is provided with in the deflection system of third embodiment of the invention.

Figure 17 B is the circuit structure diagram of expression to the convergence correction coil supplying electric current shown in Figure 17 A.

Below, with reference to the color cathode-ray tube apparatus of the description of drawings embodiment of the invention.

Schematically represent the essential structure of the color cathode-ray tube apparatus of one embodiment of the invention among Fig. 6.In this color cathode-ray tube apparatus, is furnished with vacuum casting, vacuum casting by have intersect with tubular axis (Z axle) and orthogonal trunnion axis promptly first (H axle) and vertical axis are the rectangular-shaped screen dish 10 of second (V axle), funnelform cone 11 that is connected with this screen dish 10 and the neck cylindraceous that is connected with the small-caliber end of this cone 11 12 constitute, according between the center of screen dish 10 and the diagonal angle end along the drop (along the range difference of tubular axis) of tubular axis (Z axle) to neck 12 sides, the flatness of determining that the fluoroscopic diagonal angle effective diameter twice that screen dish 10 has the radius of curvature of the screen dish 10 of approximate circle to illustrate in the back is above.Small-bore part 13 from cone 11 sides of this neck 12 to cone is installed deflection system 14.On the inner surface of screen dish 10, be provided with have that emission is blue, green, the phosphor screen 15 of the tri-color phosphor layer (illustrated example is a strip) of the point-like of ruddiness or strip.In addition, the opposed shadow mask 17 in free gap between configuration and this phosphor screen 15, in this shadow mask, by predetermined configuration section apart from forming a plurality of electron beam through-holes 16, these a plurality of electron beam through-holes 16 have the electron beam that allows its opposed faces by and the what is called of shielding on the luminescent coating of correspondence select the look function.In addition, in neck 12, the three-beam electron-beam 183 of emission one row configuration, the electron gun arrangements 19 of 18G, 18R are set, this three-beam electron-beam is made up of center electron beam 18G and an opposite side electron beam 18B, the 18R by same horizontal plane.And, on the outside of the neck 12 at above-mentioned deflection system 14 rear portions, PCM (colour purity convergence magnet) (not shown) is installed.

Above-mentioned electron gun arrangements 19 has three negative electrodes of a row configuration in the horizontal direction, heats three heated filaments of these negative electrodes and a plurality of electrodes that dispose to phosphor screen 15 directions from negative electrode.Utilize this a plurality of electrodes, form to make at least and focus on main lens on the screen from three-beam electron-

beam

18B, 18G, the 18R of a row configuration of cathode emission, in addition, by applying and the synchronous voltage that changes of the deflection of deflection system 14, form and disperse the attachment lens that focuses in the horizontal direction in vertical direction.

Deflection system 14 has horizontal deflection coil and frame deflector coil, horizontal deflection coil produces three-beam electron-beam 18B, the 18G make from electron gun arrangements 19 emissions, the 18R horizontal deflection magnetic field of upper deflecting in the horizontal direction, and frame deflector coil produces the vertical deflection magnetic field that makes its deflection in vertical direction.As shown in Figure 7, the horizontal deflection magnetic field 22H of its horizontal deflection coil 21a, 21b generation produces roughly magnetic field uniformly.If make such horizontal deflection magnetic field even, compare with pincushion horizontal deflection magnetic field in the past so, for electron beam towards phosphor screen diagonal angle end, the vertical composition of the horizontal deflection magnetic field that works on the direction that hinders vertical deflection reduces, as shown in Figure 8, the upper and lower side of picture 24 is deformed into pincushion.Therefore,, in deflection system 14, be provided with the distortion correcting unit (not shown) that one group of NS magnet constitutes, and strengthen the function of proofreading and correct this distortion in order to proofread and correct this pincushion anamorphose.On the other hand, for the vertical deflection magnetic field that frame deflector coil produces, be defined as barrel-shapedly, strengthen this barrel field, the under convergence that produces with this barrel-shaped vertical deflection magnetic field compensates because of strengthening the over convergence of above-mentioned distortion calibration function at the upper and lower side of picture 24.

In other words, in the deflection system of one embodiment of the invention, come the correct for both pincushion anamorphose by the convergence of satisfying picture 24 upper and lower sides.

And, in the color cathode-ray tube apparatus of one embodiment of the invention, from the negative electrode of above-mentioned electron gun 19 between the center of deflection system 14, three-beam electron-

beam

18B, 18G, 18R are provided with the convergence correction unit (not shown) that is made of magnetic cell or electric unit that an opposite

side electron beam

18B, 18R are moved like that away from center electron beam 18G (under convergence) in the orientation of three-beam electron-

beam

18B, 18G, 18R when the horizontal direction periphery of phosphor screen 15.

As mentioned above, as shown in Figure 7, if the horizontal deflection magnetic field 22H that horizontal deflection coil 21a, 21b produce is a uniform magnetic field, this horizontal deflection magnetic field 22H power FHB, FHG, FHR of imposing on three-beam electron-

beam

18B, 18G, 18R equates so.In color cathode-ray tube apparatus in the past, as shown in phantom in Figure 1, end becomes over convergence about fluoroscopic, and in this example, as shown in Figure 9, owing to be provided with the convergence correction unit, thus from power FSB, the FSR of convergence correction unit 25 act on phosphor screen 15 about on an opposite side electron beam 18B, the 18R at end P place, compensation is the over convergence of uniform magnetic field generation because of horizontal deflection magnetic field.But in the center O of phosphor screen 15, convergence correction unit 25 is inoperative, and three-beam electron-

beam

18B, 18G, 18R are still consistent.Have, symbol 26 is PCM again.

Therefore, if constitute color cathode-ray tube apparatus as described above, end about phosphor screen 15 is identical with conventional art so, and because of the horizontal flattening of the homogenizing electron-beam point of horizontal deflection magnetic field 22H relaxes, definition improves.

On the other hand, because vertical deflection magnetic field still is non-homogeneous (it is barrel-shaped to strengthen this certainly) magnetic field, so upper and lower side at phosphor screen 15, can think the effect identical that do not have with the technology of document A, B, C, but incidence angle to phosphor screen 15 for

electron beam

18B, 18G, 18R, because its incidence angle of periphery at phosphor screen 15 diminishes, so electron-beam point is deformed into the shape of extension on transmit direction.Therefore, the diminish influence that produces of influence that end about phosphor screen 15, magnetic deflection field heterogeneous produce electron-beam point and incidence angle becomes the direction of mutual reinforcement, and the distortion of electron-beam point increases, and at upper and lower side, both influences become the direction of mutual compensation.Therefore, the distortion of electron-beam point is alleviated, and at the upper and lower side of as shown in figure 10 picture 24, electron-beam point 28B, 28G, 28R be not distortion basically.Certainly relevant with vertical deflection, barrel-shaped vertical deflection magnetic field is because of the reinforcement of distortion correcting unit with opposite lensing, and slightly vertically flattening on the contrary becomes.

In addition, if constitute color cathode-ray tube apparatus as described above, do not need the convergence correction of vertical axis so basically.In this example, the current supply circuit of convergence correction unit 25 is only arranged on horizontal axis, omit the current supply circuit of vertical axis.

Have again, in the above-described embodiments, be illustrated, but on the contrary, this convergence correction unit also can play the over convergence effect at fluoroscopic center for the convergence correction unit of about phosphor screen, having held the under convergence effect.In other words, with respect near the situation the phosphor screen center, three-beam electron-beam relatively towards about the end situation under, the convergence correction unit also can make electron beam become on the direction away from center electron beam.

In addition, horizontal deflection magnetic field is not limited to uniform magnetic field, by changing the correcting value of convergence correction unit, also can form weak pincushion and barrel-shaped to horizontal deflection magnetic field.If make such horizontal deflection magnetic field become non-uniform magnetic-field, it is barrel-shaped that horizontal deflection magnetic field is become, increase the compound lens multiplying power of holding about phosphor screen so in vertical direction, dwindle the compound lens multiplying power of holding about phosphor screen in the horizontal direction, electron-beam point can be flattened in vertical direction, the distortion of the electron-beam point that produces because of above-mentioned incidence angle can also be compensated.

Figure 11 represents to be provided with the deflection system more specifically of the embodiment of the invention of correct convergence unit.Deflection system 14 shown in Figure 11 has makes electron beam a pair of horizontal deflection coil 21a, the 21b up and down of upper deflecting in the horizontal direction, makes pair of right and left frame deflector coil 30a, 30b and the magnetic magnetic core 31 of electron beam deflection in vertical direction.On the neck side (rear portion side suitable) of this deflection system 14 with right side on the drawing, dispose a pair of on magnetic core 33a, the 33b of the shape that has its right angle, claval both sides to extend the coil 34a, the 34b that do not have commatic aberration of coiling coil (not shown), wherein the elongated end of magnetic core 33a, 33b is opposed mutually.In addition, on the fluorescence screen side (toe lateral suitable with the drawing upper left side) of deflection system 14, a pair of bar-shaped NS magnet 35a, 35b are configured to proofread and correct the unit that results from the distortion in the electron beam up and down for they.

And, in the present embodiment, on above-mentioned a pair of magnetic core 33a, the 33b that does not have commatic aberration coil 34a, a 34b, reel as coil 36a, the 36b (convergence correction coil) of correct convergence unit.This convergence correction coil 36a, 36b reel at adjacent quadrant Semi-polarity on the contrary by four magnetic poles that the fore-end that makes magnetic core 33a, 33b produces, and the quadripolar magnetic field by energising produces has the effect that makes an opposite side electron beam over convergence or under convergence.

Figure 12 represents the convergence correction current supply circuit as the coil supplying electric current of convergence correction unit.This convergence correction current supply circuit 37 comprises the current output circuit part 37 that makes the convergence correction coil motion, this current output circuit part 37 is made of amplifier 38 and feedback resistance 39, and supply part, DC power supply 41a, 41b and the ground wire 42 etc. of the parabolic waveform voltage 40 that changes simultaneously with horizontal deflection frequency all are installed on the color cathode-ray tube apparatus.Parabolic waveform voltage 40 when Hi-Vision machine or high-resolution monitor, because of producing and the synchronous focus voltage that changes of the deflection of electron beam, then can use this focus voltage as parabolic waveform voltage 40.In this current output circuit part 37, between amplifier 38 and ground wire 42, be connected the convergence correction coil 36 of connecting and (reduce coil 36a, 36b with feedback resistance 39, and represent with symbol 36), convergence correction coil 36 1 sides of feedback resistance 39 feed back to amplifier 38.Therefore, if on amplifier 38 input parabolic waveform voltage 40, the poor of its voltage and feedback voltage eliminated in amplifier work so, the result supplies with action with parabolic waveform voltage 40 same waveform as electric currents to convergence correction coil 36.

Therefore, because such current output circuit is only changed the action of output because of the same shape electric current of the input generation of parabolic shape waveform voltage, so the drive circuit side divert as parabolic waveform voltage 40 that supply with the electron beam deflecting original focus voltages of change synchronously, and can only supply with as power supply can with DC power supply 41a, the 41b of original DC power supply dual-purpose.In addition, compare, on the voltage of deflection system, do not strengthen all electric power burdens, can obtain near desirable parabolic waveform electric current with the example in the past that on deflection system, directly forms the parabolic waveform electric current.

Have, above-mentioned amplifier 38 is made of transistor etc. usually again, but owing to can purchase anti-high frequency, high-power various OP amplifiers (operational amplifier) in market recently, so, can suppress the scale and the cost of circuit by adopting these OP amplifiers.

In addition, such current output circuit part suppresses the unit as energy, uses diode etc., utilizes the sharp-pointed part of excision parabolic waveform voltage 40, also can input to amplifier 38.Because the sharp-pointed part of this parabolic waveform voltage 40 is the parts by the high frequency change, so when making current waveform follow voltage waveform, the energy consumption of amplifier 38 increases.Therefore, by excising the sharp-pointed part of above-mentioned parabolic waveform voltage 40, the voltage of input smooth waveform can suppress consumed power, and can constitute amplifier 38 at an easy rate.Have again, because the sharp-pointed part of parabolic waveform voltage 40 appears on the picture not during the reveal competence return line, so do not influence picture.

In addition, if on parabolic waveform voltage 40 overlapping input direct voltage, can adjust the convergence of an opposite side electron beam of horizontal direction on the whole image so, the user can utilize when adjust assembling.

In addition, as mentioned above,, on deflection system, from horizontal deflection voltage or horizontal yoke current, also can form the parabolic waveform voltage 40 of horizontal deflection frequency even do not import parabolic waveform voltage 40 from the outside.Figure 13 represents its parabolic waveform voltage forming circuit.This parabolic waveform voltage forming circuit 43 has the circuit that is connected with ground wire 42 by capacitor 44 and shunt resistance 45 on the negative side of horizontal deflection coil 21a, 21b.If be provided with such circuit, the jagged horizontal yoke current that flows in horizontal deflecting circuit is diverted in the capacitor 44 by shunt resistance 45 so, the savings electric charge, by the discharge of this savings electric charge, can take out the parabolic waveform voltage 40 of horizontal deflection frequency from shunt resistance 45 sides.

Even form such parabolic waveform voltage 40, because electric power from the above-mentioned voltage-to-current converting system of the direct-current power supply of outside, so directly form parabolic waveform voltage, can not cause to resemble influences deflection power the conventional art, makes the problem of waveform confusion of the parabolic waveform electric current of formation simultaneously.

In addition, negative side at horizontal deflection coil 21a, 21b is provided with the resistance 46,47 that detects zigzag voltage, by making the jagged horizontal yoke current shunting of flowing through horizontal deflecting circuit, form the zigzag voltage waveform 49 of zigzag voltage waveform 48 and reverse this voltage waveform 48, utilize variable resistor 50 suitably to cut apart above-mentioned voltage waveform 48,49, form jagged voltage waveform, it is overlapped on the above-mentioned parabolic waveform voltage 40, be input in the amplifier 38 of current output circuit part.According to such circuit,, can adjust the differential convergence correction amount in the picture left and right sides by adjusting variable resistor 50.

In addition, similarly, be variable resistor, can adjust the amplitude of parabolic waveform voltage, can adjust whole convergence correction amount by making shunt resistance 45.

In addition, as shown in figure 14, extract the alternating component of the horizontal deflection voltage of pulse type by capacitor 52 from the negative side of horizontal deflection coil 21a, 21b, diode 54a, the 54b and capacitor 55a, the 55b that utilize resistance 53a, 53b and be connected in series respectively with these resistance 53a, 53b, DC power supply 41a, 41b as current output circuit part amplifier 38 supplies with the positive part of the alternating component of horizontal deflection voltage or negative part, can not need from the supply of external dc power, this power unit 56 is arranged on the deflection system.

In this case, because the power of above-mentioned voltage-to-current conversion is also supplied with from the power supply of deflection system, form relevant power so on deflection power, can share, and can not cause the confusion of parabolic waveform electric current with the parabolic waveform electric current.

Therefore, utilize such convergence correction current supply circuit to make the convergence correction coil motion, the pincushion of the horizontal deflection magnetic field by making deflection system weakens simultaneously, can make the convergence unanimity on the whole image, and can improve the distortion of electron-beam point on the whole phosphor screen.

But, in the present embodiment, if the pincushion of horizontal deflection magnetic field weakens, so for electron beam towards phosphor screen diagonal angle end, the vertical component of the horizontal deflection magnetic field that acts on the direction that hinders vertical deflection reduces, in the upper and lower side generation pincushion distortion of picture shown in Figure 8 24.Therefore, in the present embodiment, when strengthening one group of NS magnet 35a shown in Figure 11,35b magnetic force, be necessary to strengthen the barrel-shaped of vertical deflection magnetic field.If strengthen the magnetic force of a pair of like this NS magnet, the convergence to the side electron beam of phosphor screen upper and lower side plays the over convergence effect so.In addition, if the barrel-shaped of vertical deflection magnetic field is reinforced, vertical deflection magnetic field does up the under convergence effect to electronics so.Therefore, as mentioned above, improve and strengthen the barrel-shaped of NS magnet and vertical deflection magnetic field, satisfying the pincushion distortion that to proofread and correct the picture upper and lower side under the state of assembling.

Therefore, utilize structure as described above, can only finish the correction of convergence basically, can simplify the structure of convergence correction unit with the correction of horizontal direction.

As concrete example, using diagonal angle effective diameter 46cm, curvature probably to be the screen dish of 3 times of diagonal angle effective diameters, maximum deflection angle is 100.The color cathode-ray tube apparatus of in-line self-convergent system in, utilize above-mentioned convergence correction unit, end carries out about relatively 8mm under convergence correction about with respect to the phosphor screen center, and weakens the pincushion of other parts horizontal deflection magnetic field.Its result can be improved to 0.55 to the horizontal diameter/perpendicular diameter of the electron-beam point of end about fluoroscopic from original 0.35.

Simultaneously, about fluoroscopic, hold, can become 370V to the dynamic change voltage that must reach 600V originally.This is the cause that non-some aberration is also relaxed because of the distortion improvement effect by above-mentioned electron-beam point.And, increase by making the convergence correction amount, can also be in the distortion of longitudinal direction colonel positron beam point.In addition, the voltage of dynamic change finally can be reduced to the value that defocuses the last necessity of correction because of resembling the crooked aberration of face.

Have again, in the above-described embodiments, the convergence correction coil is wound on structure on the magnetic core that does not have the commatic aberration coil,, can design the convergence correction unit compactly so can eliminate unnecessary structure member owing to have.

In addition, as shown in figure 15, in the convergence correction unit, also can adopt toroidal core 57 with ferrite system as magnetic core, coiling convergence correction coil 36a on four interior side-prominent juts 58 of this toroidal core 57 (36d, the structure of generation quadripolar magnetic field.In this case, (magnetic core of 36d preferably has four, if but the degree of freedom that does not have the commatic aberration coil distribution that consideration is reeled simultaneously as shown in the figure, expects to be provided with eight left and right sides juts 58 as convergence correction coil 36a.Specifically, the area of section of jut 58 is that (5mm, (36d compares with the situation on the magnetic core of the silicon steel sheet system of being wound on 5mm, can improve the sensitivity of orbit correction by coiling convergence correction coil 36a in this jut 58.

The sensitivity that such convergence correction unit can improve convergence correction by the area of section that increases magnetic core, but use low-cost silicon steel sheet, the area of section is big more, is easy to generate harmful effects such as heating that the horizontal deflection magnetic field because of high frequency change produces and induction field more.Therefore, it is effective constituting the convergence correction unit with the such highly-resistant material of above-mentioned ferrite.

And, as shown in figure 16, (36d constitutes, also can (36d disposes like that by main lens to the vacuum casting between the deflection system center that surrounds from electron gun these four convergence correction coil 36a by bending to four circular-arc convergence correction coil 36a in the convergence correction unit.In such convergence correction unit,, convergence correction sensitivity is improved by making length of magnetic path L lengthening.But, if (36d so just can not improve as the distortion of the electron-beam point of problem points in the past not near fluorescence screen side convergence correction coil 36a.In addition, if (36d near cathode side, does not make the orbit transfer by the electron beam of main lens to convergence correction coil 36a so, might produce the deterioration of electron-beam point because of the spherical aberration of lens.Therefore, ideal situation is preferably installed the neck of deflection system.

And, the convergence correction unit is not limited to produce the situation of quadripolar magnetic field, for example, as shown in figure 17, about the ring-shaped core 60 that is configured in deflection system neck side, convergence correction coil 36a, 36b toroidal are reeled, and these convergence correction coils 36a, 36b also can be connected with horizontal deflection coil 21a, 21b by the circuit shown in Figure 17 B.This circuit has such structure, on the magnetic bias saturable magnetic core 62 that produces by magnet 61a, 61b, the variable load coil 63a, the 63b that reel and be connected with horizontal deflection coil 21a, 21b on the direction of mutual compensating field connect convergence correction coil 36a, 36b on these variable load coils 63a, the 63b that is connected in parallel.

In this convergence correction unit, if flow horizontal yoke current, a load because of magnetic saturation variable load coil 63a, 63b increases so, and another load reduces.Thus, at fluoroscopic left end, one of them magnetic field of convergence correction coil 36a, 36b becomes bigger than another magnetic field, in the reversally differential action of the big I in its magnetic field of right-hand member.Therefore, structure is used helping on the direction of horizontal deflection side electron beam to common deflection side to constitute to pretend in the magnetic field of this convergence correction unit by above-mentioned convergence correction coil 36a, the differential generation of 36b, or formation is used structure to pretending with the side electron beam formation of common deflection side opposition side on the direction that hinders horizontal deflection, can proofread and correct the convergence of an opposite side electron beam.

As mentioned above, from the gun cathode of the in-line self-convergent system color cathode-ray tube apparatus that high-quality television set and high-resolution monitor etc., uses between the center of deflection system, if be provided with the convergence correction unit, all do not have the distortion of electron-beam point so on the whole image, can reach approximate proper circle.In addition, by the convergence correction current separation being become voltage/current conversion portion and correction voltage generation part, can obtain desirable correcting current, and can from deflection power, isolate consumed power.

Claims

1. color cathode-ray tube apparatus comprises:

Deflection system, be installed in the outside of neck to the small-bore part of cone, make the deflection system of three-beam electron-beam as generation along the magnetic deflection field of first and the second direction of principal axis deflection, for the first axial magnetic deflection field, the main non-uniform magnetic-field composition that makes electron-beam point deterioration on the phosphor screen that reduces, for the second axial magnetic deflection field, main proofread and correct leave first along the first axial anamorphose and convergence and

The convergence correction unit, from the negative electrode of electron gun between the center of deflection system, main only along the first axial peripheral part with respect to the phosphor screen center, make opposite side electron beam displacement relatively on away from the direction of center electron beam.

2. color cathode-ray tube apparatus comprises:

3. color cathode-ray tube apparatus as claimed in claim 2, electron gun comprises the electrode that forms main lens, on this electrode, apply parabolic shape waveform voltage, and the input voltage of amplification circuits is the voltage of described parabolic shape waveform voltage of migrating to the synchronous change of first of deflection system and second at least one direction deflection.

4. color cathode-ray tube apparatus as claimed in claim 2, the input voltage of amplification circuits are the voltage of the high frequency change part of input voltage during the level and smooth vertical retrace line.

5. color cathode-ray tube apparatus as claimed in claim 2, described convergence correction unit comprises according to the deflecting voltage of deflection system or deflection current circuit and forms voltage forming circuit part to the input voltage of amplification circuits that this voltage forming circuit partly is installed on the color cathode-ray tube apparatus.

6. color cathode-ray tube apparatus as claimed in claim 2 also is included in the power unit that the deflecting voltage of handling deflection system on the circuit makes amplification circuits work, and this power unit is installed on the color cathode-ray tube apparatus.

7. color cathode-ray tube apparatus comprises: