HK1025662B - Video display deflection apparatus comprising a saddle shaped deflection winding having a winding space - Google Patents

Description

Video display deflection arrangement comprising a saddle shaped deflection winding with a winding space

Technical Field

The present invention relates to a deflection yoke for use in a color Cathode Ray Tube (CRT) of a video display device.

Background

CRTs that produce color images typically include an electron gun that emits three coplanar electron beams (R, G and B beams) to excite luminescent materials of a given primary color red, green, and blue, respectively, on a phosphor screen. The deflection yoke is mounted on the neck of the tube and generates deflection fields from its horizontal and vertical deflection coils or windings. In a conventional manner, a ring or core of ferromagnetic material surrounds the deflection coil.

To avoid a landing error of the electron beams, called a convergence error, the three electron beams generated are required to converge on the screen, otherwise a deviation in color reproduction occurs. To provide convergence it is known to use an astigmatic deflection field known as self-convergence. In a self-converging deflection coil, the field inhomogeneities, which are produced by the horizontal deflection coils and are delineated by the field lines, are generally pincushion-shaped in the front portion of the coil closer to the screen.

Due to the aspherical shape of the screen surface, a geometric distortion called pincushion distortion is locally generated. As the radius of curvature of the screen increases, the distortion of the image, known as north-south distortion at the top and bottom of the image and east-west distortion at the sides of the image, becomes larger.

Because the R and B beams pass through the deflection zone at a small angle relative to the longitudinal axis of the tube, they also undergo additional deflection relative to the deflection of the central G beam, thus producing coma. With regard to the horizontal deflection field, coma is usually corrected by generating a barrel-shaped horizontal deflection field in the beam entrance region or in the region of the deflection yoke behind the above-mentioned pincushion field for convergence error correction.

The green image is gradually shifted horizontally with respect to the midpoint between the red and blue images as the scan line goes from the center to the corners of the screen, exhibiting coma parabola distortion on the vertical lines at the sides of the images. If the shift is made toward the outside or side of the image, such coma parabola error is generally referred to as positive; such coma parabola error is generally referred to as negative if the shift is toward the inside or center of the image.

Horizontal trapezoid errors occur due to field astigmatism. When the displayed image is a rectangular test pattern, the error is displayed on the tube phosphor screen, for example, as shown in FIG. 6a, the blue image is rotated relative to the red image. Since the conductor constituting the horizontal deflection coil having the winding distribution selected to optimize other parameters (convergence error, geometric distortion, etc.), a high-order deflection field coefficient or harmonic wave causing a trapezoidal difference is generated, and thus a horizontal trapezoidal error occurs. The irregular quadrilateral difference may cause, for example, a tilt reversal of the blue image between 1H (1 o 'clock on the phosphor screen) and a point representing the corner of the image at 2H (2 o' clock on the phosphor screen), as shown in fig. 6 b.

It is customary to divide the deflection field along the longitudinal axis of the tube into three successive regions of action: the back or rear region closest to the electron gun, the middle region and the front region closest to the screen. Coma is corrected by controlling the field in the posterior region. The geometric errors are corrected by controlling the field in the front area. Convergence errors are corrected in the rear and middle regions and have minimal effect on convergence errors in the front region.

For example, in the prior art deflection system of fig. 2, permanent magnets 240, 241, 242 are disposed at the front of the deflection system to reduce geometric distortion. Other magnets 142 and field shapers are inserted between the horizontal and vertical deflection coils to locally modify the field to reduce coma, coma parabola error and convergence error.

When the screen has a large radius of curvature greater than 1R, for example, 1.5R or more, it becomes increasingly difficult to solve the beam landing error without using magnetic auxiliary components such as shunts or permanent magnets or the like.

It is desirable to reduce errors such as trapezoidal errors, coma parabola errors, coma or convergence errors by controlling the winding distribution of the deflection coils without using magnetic auxiliary components such as shunts or permanent magnets.

It is desirable to eliminate these auxiliary components because shunts or permanent magnets disadvantageously create heating problems in the system associated with higher horizontal frequencies, particularly when the horizontal frequency is 32kHz, or 64kHz or above. In a sense, these additional components also increase the unwanted deviations in the produced deflection system, thereby reducing the correction of trapezium errors, geometrical errors, coma parabola errors and convergence errors.

In the inventionContainer

A video display deflection apparatus embodying features of the invention, comprising:

a saddle-shaped horizontal deflection coil for generating a horizontal deflection field to scan the electron beam along a horizontal axis of a display screen of the cathode ray tube, the horizontal deflection coil includes a plurality of winding turns forming a pair of side portions, a front end turn portion adjacent the screen, and a rear end turn portion adjacent the tube electron gun, said side portions forming a winding window with no wire therebetween, the length dimension of the winding window being defined by the distance between said front end turn portion and said rear end turn portion, at least one of said side portions having a winding gap for correcting electron beam landing errors of trapezoidal shaped differences, the winding gaps constitute slots occupying an angular range selected between 30 degrees and 45 degrees and having a length dimension greater than half the length dimension of the winding window along the longitudinal axis;

a vertical deflection coil for scanning said electron beam along a vertical axis of said phosphor screen to form a raster; and

a magnetically permeable core, together with said horizontal and vertical deflection coils, forms a deflection yoke.

Advantageously, forming the window gap in an angular range between 30 degrees and 45 degrees reduces the above-mentioned trapezoid error. A reduction in the trapezoidal error can be obtained without using shunts or magnets in the system.

Drawings

FIG. 1 shows a deflection yoke mounted on a cathode ray tube in accordance with the inventive arrangements;

FIG. 2 shows a front exploded view of a deflection system according to the prior art;

FIG. 3 shows a cross-sectional view of a saddle coil formed at a coil mid-region configured in accordance with the present invention;

FIGS. 4a and 4b show side and top views, respectively, of a coil configured in accordance with the present invention;

FIGS. 5a and 5b show the effect of the variation of the coefficients of the horizontal deflection field distribution function along the tube principal axis Z and the winding windows and winding gaps formed in the coils produced by a coil configured in accordance with the present invention; and

fig. 6a and 6b show the electron beam landing errors of the trapezoids between the two types of red and blue images.

Detailed Description

As shown in fig. 1, the self-converging color display device comprises a Cathode Ray Tube (CRT) provided with an evacuated glass envelope 6 and a phosphor or light-emitting cell arrangement representing the three primary colors R, G and B disposed at the end of the envelope constituting a display screen 9. An electron gun 7 is arranged at the second end of the housing. For exciting the respective luminescent color unit, the set of electron guns 7 is arranged such that it generates three electron beams 12 which are horizontally aligned. The electron beam is caused to scan the phosphor screen surface by operation of the deflection system 1 mounted on the neck 8 of the tube. The deflection system 1 comprises a pair of horizontal deflection coils 3 and a pair of vertical deflection coils 4, which are isolated from each other by an isolator 2, and a magnetic core of ferromagnetic material 5 for enhancing the field on the electron beam path.

Fig. 4a and 4b show a side view and a top view, respectively, of one of the pairs of saddle-shaped horizontal coils or windings 3 according to an aspect of the present invention. Each winding turn is formed by a loop of wire. Each of the pairs of horizontal deflection coils 3 has a rear end turn portion 19 proximate to the electron gun 7 of fig. 1 and extending along the longitudinal or Z-axis. The front end turn portion 29 of fig. 4a and 4b, disposed proximate to the display screen 9 of fig. 1, is bent away from the Z-axis in a direction generally perpendicular to the Z-axis. It is preferable to manufacture each of the magnetic core 5 and the separator 2 in a single piece rather than in an assembly of two separate parts.

The wires of the front end turn portion 29 of the saddle coil 3 of fig. 4a and 4b are connected with the rear end turn portion 19 by side wire bundles 120, 120 along the Z-axis on one side of the X-axis and together constituting one side portion and side wire bundles 121, 121 on the other side of the X-axis together constituting the other side portion. The portions of the side strands 120, 120 and 121, 121 located close to the yoke-deflecting field beam exit region 23 form the front gaps 21, 21 and 21 "of fig. 4 a. The front gaps 21, 21 and 21' affect or change the current distribution harmonics to correct for geometrical distortion of the image such as north-south distortion, for example, formed on the screen. Likewise, the portions of the side wire bundles 120, 120 and 121, 121 that are located in the entrance area 25 of the deflection coil 3 form the rear gaps 22 and 22. The gaps 22 and 22 have a winding distribution selected to correct horizontal coma. The end turn portions 19 and 29 and the side wire bundles 120 and 121 define the main winding window 18.

The area along the longitudinal Z-axis of the end turn portion 29 defines a beam exit zone or region 23 of the coil 3. The region along the longitudinal Z-axis of the window 18 defines an intermediate zone or region 24. At one extreme, the window 18 extends from the Z-axis coordinate of the corner 17 where the side strands 120 and 121 are connected. The other extreme of the window 18 is defined by the portion 29. The area of the coil located in the rear behind the window 18 and including the rear end turns 19 is referred to as the beam entry region or area 25.

The side wire bundles 120 with the corners 60 include most of the wires at the corners. The other side wire bundle 120' forms the side boundary of the winding window 18.

Coma is corrected primarily in the posterior or entrance region 25. Geometric errors such as east-west and north-south distortions are corrected primarily in or near the exit zone 23. The influence on the convergence error is minimal in the exit zone 23 and the convergence error is mainly corrected in the intermediate zone 24 and the entrance zone 25.

Fig. 3 is a cross-sectional view of the saddle coil 3 in a plane where the intermediate zone 24 is parallel to XY. For reasons of symmetry, the figure shows only a cross section of one half of the coil. The half-coil includes strands 120, 120 of conductor 50. Each conductor position is represented by its radial angular position θ. The conductive line group 120 is disposed between zero degrees and θ L degrees, and the conductive line group 120 is disposed between θ 1 and θ 2.

Due to winding symmetry, the fourier series expansion of the ampere-turn density N (θ) of the coil can be written as:

n (θ) ═ a1 · cos (θ) + A3 · cos (3 θ) + a5 · cos (5 θ) +, a

Wherein:

(formula 2)

The magnetic field is represented by the following formula:

H＝A1/R+(A3/R³)·(X²-Y²)+(A5/R⁵)·(X⁴-6X²·Y²+Y⁴) +.. (equation 3)

Where R is the magnetic path radius of the ferrite core around the deflection coil. The term A1/R represents the zero-order coefficient or fundamental wave field component of the field distribution function, the term (A3/R)³)·(X²-Y²) Representing the second order coefficient of the point field distribution function at coordinates X and Y and related to the third harmonic of the winding distribution. Term (A5/R)⁵)(X⁴-6X²·Y²+Y⁴) Representing a fourth order coefficient or a fifth order harmonic of the field, etc.

The positive term a3 corresponds to the quadratic coefficient of the positive field on the axis that produces the pincushion field. In the case where current circulates in the same direction in all wires, N (θ) is generally positive, and if the wires are set between an angle of θ 0 degrees and an angle of θ 30 degrees, the term a3 is positive. This is because cos (3 θ) is positive. Significant positive quadratic coefficients of all positive fields and positive quartic coefficients of the fields can be introduced locally by arranging the conductor within a predetermined angular range.

In order to maintain convergence of the electron beams from the in-line electron gun, it is known to make the quadratic coefficient of the linear deflection field of the intermediate zone 24 positive. To this end, a majority of the wires of the side wire bundle 120 are maintained within a range of radial angular positions between 0 and 30 degrees, at least in a portion of the intermediate zone 24. However, since the method of controlling the convergence of the electron beam introduces a large coma parabola error, it is necessary to correct the coma parabola error as will be described later.

The saddle coils of fig. 4a and 4b may be wound with small sized copper wires covered with an electrical insulator and a thermosetting glue. The winding is performed in a winding machine which winds the saddle coil substantially in its final shape and introduces the gaps 21, 21 ", 22 in fig. 4a and 4b during the winding process. The shape and location of these gaps is determined by retractable pins in the winding head that limit the shape of these gaps by forming corners in each gap.

After winding, the respective saddle coil is held in a mould and also subjected to pressure in order to obtain the required mechanical dimensions. The current is passed through the wires in order to soften the thermosetting glue and then cooled again in order to bond the wires to each other and form a self-supporting saddle coil.

The location of the gap 21 "formed in the intermediate zone 24 is determined during the winding process by the pin located at position 60 of fig. 4a in the central region of the intermediate zone 24. The result is that a corner or corner portion is formed in the gap 21 "at location 60.

The pins cause, in a well-known manner, a sudden change in the winding distribution and the formation of corresponding corners in the winding gaps. On the side of position 60 in fig. 4a closer to the entrance area, the closer to the corner position 60, the greater the concentration of the wire. On the other hand, on the side of corner position 60 closer to the exit area, the degree of wire concentration decreases as the distance from position 60 increases. Thus, the wire concentration is locally greatest at location 60.

The location of the gap 26 formed in the back of the intermediate zone 24 is determined by the pin located at location 42 at the back of the intermediate zone 24 during the winding process. The result is the formation of a corner at the location 42 of the gap 26. Position 42 is located 56mm from the front of the coil for the Z axis, near the rear limit point or corner 17 of the main window 18. The rear end 17 defines the furthest coordinate of the window 18 in the Z-axis from the front of the coil. The corner 17 is located at a distance of 59mm from the front of the coil for the Z axis. The gap 26 extends between 47mm and 62mm from the front of the deflection coil along the Z axis.

The gaps 21 "and 26 are located in the side portions formed by the wire bundles 120 and 120. The pin at position 60 is near the center of the middle zone 24. The pin at position 42 is located towards the rear of the middle region of the corner 17.

Advantageously, the position 42 is selected within a range bounded by one end represented by the Z-axis coordinate of the corner 17 of the window 18 and the other end represented by the Z-axis coordinate spaced from the corner 17 by about 10% of the length of the intermediate zone 24. The length of intermediate zone 24 is equal to the difference between the Z-axis coordinate of the border of window 18 formed by end turn portion 29 and the Z-axis coordinate of corner 17 of window 18. Selecting the coordinates of position 42 within such a range of 10% of the length of the intermediate zone improves coma parabola correction. This also avoids the use of shunts or magnets.

For analytical purposes, the values of convergence error and coma were compared between a conventional or traditional first coil, in which the side wire bundles were arranged with a substantially constant radial density between 0 and 50 degrees, and an imaginary second coil, which was similar in some respects to the coils of fig. 4a and 4 b. In the second coil, 94% of the side wire bundles in a longitudinal position substantially in the middle of the middle area 24 are concentrated in a radial opening range between 0 and 31 degrees, which results in a transverse winding gap in the winding similar to the transverse winding gap 21 "of fig. 4 a. Further, comparing the convergence error value and the coma value of the conventional first coil, whose side wire bundles are arranged at a substantially constant radial density between 0 and 50 degrees, with the imaginary third coil. In the third coil, 49% of the side wire bundles located in a longitudinal position behind the intermediate zone 24 are concentrated near the entrance zone 25 and in a radial opening range between 0 and 33 degrees, resulting in a transverse winding gap in the winding similar to the transverse winding gap 26 of fig. 4 a.

The following table demonstrates the improvement in convergence error and coma error but degrades coma parabola error for the second and third coils relative to the conventional or conventional first coil. The coma parabola error increases from 0.44mm to 0.83mm in the second coil and from 0.44mm to 0.53mm in the third coil.

In the table below, coma (horizontal and vertical) and convergence errors are measured at nine points, typically representing one quadrant of the screen of the cathode ray tube. As noted, the two modified structures of the second and third coils change the coma parabola in opposite directions. This feature is best used in the configuration of fig. 4a and 4b to reduce the coma parabola error value to an acceptable value close to zero.

	Blue/red convergence	Coma aberration at the green level relative to the red/blue average	Coma parabola error
				No gaps 21 "and 26	0.40 0.54 3.180.20 1.76 9.210 1.89 9.80	0 1.07 3.440 1.13 3.420 1.10 3.00	0.44
With a gap 21 ″	0.42 0.41 1.220.19 0.89 4.240 0.97 5.74	0 0.71 1.890 0.77 2.450 0.80 2.72	-0.83
				With a gap 26	0.35 0.35 1.300.15 0.87 4.970 0.74 4.22	0 0.28 0.960 0.18 0.620 0.11 0.43	0.53

Advantageously, the position of the respective pins in relation to the gaps 21 "and 26 provides separate control parameters or degrees of freedom for correcting convergence and residual coma, while enabling minimizing coma parabola error values to acceptable values. Furthermore, the use of winding gaps 21 "in the intermediate region 24 and formed in the wiring harness 120 in combination with winding gaps formed in the region 25 provides the required variation along the Z-axis, which may be advantageous to avoid the use of shunts or magnets.

In the example of fig. 4a and 4b, the deflection system is mounted on an a68SF type tube having a screen of aspherical shape and a radius of curvature on the order of 3.5R at the horizontal edge. The total length of the horizontal coil 3 along the Z axis is equal to 81 mm. The horizontal coil has a front or beam exit region or zone 23 formed by end turn conductors 7mm long along the Z axis. The horizontal coil 3 has a middle section 24 of length 52mm, in which middle section 24 the window 18 of fig. 4b extends. The horizontal coil 3 has a back or rear coil wire 19 extending 22mm in length along the Z-axis. The wires at the back of the coil are wound such that they form bundles or groups which are partially separated from each other by a gap without wires.

Viewing the coil of fig. 4a and 4b along its symmetrical YZ plane, it can be seen that: during the winding process, the pins are inserted into the positions 60 and 42 as previously described, creating the gaps 21 "and 26 in the region 24. The pin at location 60 holds the wire bundle 120 at about 94% of the number of coil wires. The pin at position 60 is located at a distance of 27mm from the front of the coil and is located at an angular position in the XY plane of 31.5 degrees approximately in the center of the middle region 24. The pin at location 42 holds the wire bundle 45 of fig. 4a at about 49% of the number of coil wires. The pin at position 42 is placed 56mm from the front of the coil in an angular position equal to 33 degrees in the XY plane.

Most geometric errors are corrected by the wire configuration in the exit region 23. Coma is partially corrected by a winding gap formed in the rear-end turn portion 19 of the beam entrance area 25.

In the configuration of fig. 4a and 4b, the convergence error and residual coma are partially corrected by operation of the intermediate zone wire portion established by the pin at position 60 and by operation of the intermediate zone wire portion established by the pin at position 42. Each correction contributes in part to a reduction in convergence errors and coma.

Advantageously, the above-mentioned convergence error and coma correction cause the coma parabola error to vary in mutually opposite directions. Thus, advantageously, coma parabola error can be reduced to an acceptable magnitude.

Fig. 5a and 5b show the effect of the gaps 21 "and 26 on the coefficients of the zeroth and higher order components of the horizontal deflection field. In fig. 5a, the variation along the Z-axis of the zero-order component coefficient H0 of the field and the second and fourth-order component coefficients H2 and H4 of the field produced by the coil of fig. 4a and 4b is provided, as compared to the variation that occurs in a similar coil without gap 21 ". In fig. 5b, the variation along the Z axis of the zero-order component coefficient H0 of the field and the second and fourth-order component coefficients H2 and H4 of the field produced by the coil of fig. 4a and 4b is provided, as compared to the variation that occurs in a similar coil without the gap 26. As illustrated in fig. 5a and 5b, each gap 21 "and 26 positively increases the coefficients of the second and fourth order components in the active region without affecting the zero order component coefficient of the deflection field.

Depending on the size of the tube and the flatness of the screen, it may be desirable to create additional gaps in the central region of region 24 to achieve the desired correction. Also, by operation of the pins at positions 60 and 42, the percentage of wire remaining in the radial opening between 0 and 30 degrees and the Z position of the pins depends on the field shape generated by the shape of the selected wire in regions 23 and 25. Thus, for example, for a predetermined effect of beam convergence, it is useful to vary the quartic coefficient of the field by extending the gap 26 more or less in the back region 25, thereby varying the effect on coma and coma parabola errors.

The following table shows the values of convergence error, coma error and coma parabola error resulting from the operation of the coil structure of fig. 4a and 4 b. The values of convergence error, coma error and coma parabola error obtained are sufficiently low and, therefore, acceptable.

(value in mm)

Blue/red convergence	Coma at the green/red level	Coma parabola error
			0.40 0.19 0.490.17 0.28 0.650 0.14 0.93	0 0.03 0.110 -0.02 0.010 0.04 0.12	-0.01

The percentage of the relevant wire that is held below a certain angular position in the XY plane by the pin at position 42, the position of the pin at position 42 relative to the Z axis, and the angular position of the pin at position 42 may be varied according to the error range to be corrected. The size of the gap 26 may vary and, as in the case of fig. 4A and 4B, may also extend into the inlet region 25.

The conventional or conventional first coil, which is considered to be prior art, has a beam landing error with a trapezoidal shape difference, as shown in the following table. The following table provides the values of the irregular quadrilateral between the red and blue images of nine conventional spots on the tube phosphor screen.

0	0.24	-0.62
			0	0.26	0.3

0

0

0

The different errors of the trapezoids are shown in fig. 6 b. In fig. 6b, the following reference numerals apply: 70 for red, 71 for blue, 60 for trapezoid error at 1H (1 o 'clock on screen), and 61 for trapezoid error in the corner of point 2H (2 o' clock on screen).

In implementing the features of the invention, the errors of the trapezoidal differences are corrected by the gap 21 "without conductors. The gap 21 "extends into the intermediate zone 24 in the Z-axis direction for a length that is greater than half the length of the intermediate zone 24 along the Z-axis. The length of the intermediate zone is equal to the length of the window 18. In order to reduce the influence of the high-order field distribution coefficients causing the problem of the trapezoidal shape difference, the gap 21 "extends in a radial angular opening in the selected XY-plane between 30 degrees and 45 degrees. It has been found that a radial direction of 40 degrees is the optimum direction for such a tube to minimize the problem of trapezoidal differences, so that the gap 21 "is generally oriented in that direction over a portion of its length along the Z-axis. To account for winding limitations of the coil in the coil die, the gap 21 "extends along the Z-axis over a length 124 so that there is no wire in the radial angle opening including a 40 degree radial direction as shown in fig. 4 a. Length 124 is equal to about 75% of the length of intermediate zone 24 along the Z-axis.

Testing for red/blue trapezoid error showed a significant improvement in this case, bringing the trapezoid difference to an acceptable value. These values are given in the table below:

0	0.13	-0.18
			0	0.25	0.21
0	0	0

in a modification mode not shown, two gaps may be formed in the side wire harness disposed with respect to the Z-axis on the region near the corner 17 of the main window 18. These two gaps may extend locally into the regions 24 and 25. In order to reduce coma, coma parabola and convergence errors, it is possible to produce groups of wires whose number can be varied in a ratio that allows to vary the effect on the field and to obtain a better effect on the coefficients of the zero and higher order components of the deflection field.

And is not limited to the above-described embodiments. To reduce the residual convergence error, coma and vertical coma parabola error, the same principle of implementation of a saddle-shaped vertical deflection coil can also be used to vary the vertical deflection field.

Claims (7)

1. A video display deflection apparatus comprising:

a saddle-shaped horizontal deflection coil for generating a horizontal deflection field to scan the electron beam along a horizontal axis of a display screen of the cathode ray tube, the horizontal deflection coil includes a plurality of winding turns forming a pair of side portions, a front end turn portion adjacent the screen, and a rear end turn portion adjacent the tube electron gun, said side portions forming a winding window with no wire therebetween, the length dimension of the winding window being defined by the distance between said front end turn portion and said rear end turn portion, at least one of said side portions having a winding gap (21') for correcting electron beam landing errors of trapezoidal shape differences, the winding gaps constitute slots occupying an angular range selected between 30 degrees and 45 degrees and having a length dimension greater than half the length dimension of the winding window along the longitudinal axis;

a vertical deflection coil for scanning said electron beam along a vertical axis of said phosphor screen to form a raster; and

a magnetically permeable core, together with said horizontal and vertical deflection coils, forms a deflection yoke.

2. The deflection device of claim 1, wherein: the winding gap (21 ") has a corner at a coordinate in the longitudinal axis direction that is closer to a coordinate of the center of the winding window between the front end turn portion and the rear end turn portion than each of the front end and rear end turn portions.

3. The deflection device of claim 2, wherein: the winding gaps (21 ") extend in a longitudinal axis direction from coordinates of the front end turn portion (29) of the winding window (18) to coordinates of the longitudinal axis direction that are further from the phosphor screen than the winding window center coordinates.

4. The deflection device of claim 1, wherein: the one side portion has a lateral winding gap (26) with a corner portion thereof located at a position selected from a range of coordinates extending in the longitudinal axis direction between a coordinate in the longitudinal axis direction of a rear end of the winding window near the rear end turn portion and a coordinate in the longitudinal coordinate direction closer to the screen than the coordinate of the rear end, wherein the coordinate closer to the screen than the coordinate of the rear end is located from the window end coordinate by a distance equal to 10% of a longest longitudinal axis direction dimension of the window.

5. The deflection device of claim 4, wherein: the transverse winding gaps (26) extend in a longitudinal axis direction to a longitudinal axis direction coordinate that is further from the phosphor screen than a longitudinal axis direction coordinate of the winding window proximate the rear end turn portion.

6. The deflection device of claim 1, wherein: the side edge portion includes: a side wire bundle (120), the side wire bundle (120) having a corner (60) and including a majority of the wires of the one side portion; and another side wire bundle (120') forming a side boundary of the winding window.

7. The deflection device of claim 6, wherein: the portions of the wire bundle (120) forming the corners (60) are formed at radial angles ranging between 0 degrees and 30 degrees.