FI59182B - AVLAENKNINGSOK AVSETT ATT ANVAENDAS VID PAO SAMMA LINJE LIGGANDE ELEKTRONKANONER - Google Patents

Description

Ε3? * 1 Γβΐ / «x ^ ANNOUNCEMENT Cq ^ o0 JSTa lBJ (11) UTLÄGGININCSSKRIPT 1 8 2 ^" latent .-., - J del at 'V * ^ (51) Kv-lk-Wci.3 H 01 J 29/76 ENGLISH — FINLAND <M> Pttanttibaktmui - PttanttmSkitlfif 1 ^ / 73 (22) Hakwnltpllvt - An * ttknin {adi ((A. 01.73 (23) Alkuptivl — Glttljhvttdij 0U. 01.73 (41) Tulkit JulklMksant - BIWIt off 73 j * r «Kist« Hhallitut N «htivtk * lp * non i · moonLjulluiwn date— want- oeh ragliffttyral — n 7 amMcm uthgd och mUkriftm pubUond 27.02.81 (32) (33) (31) Pyy4 *** r «" O ·· »··» —8 «g« rd prloritat lit. 01.72 USA (US) 217768 (71) RCA Corporation, 30 Rockefeller Plaza, New York, NY 10022, USA (US) (72) William Henry Barkov , Pennsauken, New Jersey, Josef Gross, Princeton, New Jersey, USA. the invention is directed to deflection coil units for use in the same plane and in the field of e for electron beams.

In color image display systems, such as color television receivers, a cathode ray tube is commonly used as a display device. The color television picture tube includes a pattern of phosphor portions of different colors placed inside a transparent picture surface in the tube forming the viewing surface. Three phosphor parts of different colors, red, green and blue, are generally used and these are excited to shine by three electron beams provided by an electron gun apparatus placed in the neck at the other end of this tube. These beams are modulated with video signals and are scanned over the viewing surface to form a raster and thus reproduce the image transmitted by the television. In most cases, the electromagnetic deflection coil unit includes two pairs of horizontal deflectors 2 and 59182 and two pairs of vertical deflection coils, suitably powered by the sweep currents at the sweep speed of the lines and the image field.

The color television picture tube also includes a color selection structure, such as a shading mask or aperture network placed at a short distance from the phosphor portions, and this ensures that portions of the beam representing each color match only the corresponding colored phosphor portions. This situation is necessary to ensure color purity. In addition to this requirement for color purity, it is necessary that these three rays be applied to the viewing surface as they are swept over the raster.

Scattered focus in these rays appears as a harmful color edge phenomenon at the edges of objects in an image transmitted on a TV. The alignment is measurable as the difference between the ideally superimposed red, green, and blue lines in a cross pattern that is observed on the image surface when a suitable test mark is connected to the television receiver.

These electron beams are generally aligned in the center of the viewing surface using suitable static alignment devices in which the positions of the magnets relative to these three rays are adjusted to bend the rays so that they are aligned with the center of this image surface.

When these rays are deflected from the center of this image surface, they are directed to points not reaching the image surface, because this image surface is relatively planar and the rays tend to align with points on a spherical surface whose radius is not less than the distance from the beam deflection plane to the center of this image surface.

Scattered alignment may also be caused by aberrations in the deflection coil unit, such as astigmatism, which may have an uneven and detrimental effect on these aberrant beams in the deflection field of this deflection coil unit.

The scattering of these beams is generally corrected using dynamic alignment correctors placed around the neck of the picture tube, which include electromagnets powered by line and image field sweep waveforms to dynamically change the amount of alignment correction provided to these beams. Such hardware I am not complicated and expensive.

59182 A color television picture tube may use electronic road cannon equipment to develop three horizontal beams in the same plane and on the same segment, together with a picture surface containing phosphor portions placed on adjacent vertical strips. The advantages of a system using this type of picture tube are described in detail in another Finnish patent application No. 16/73 by A.M. Morrell et al., With the designation of the invention being "Self-Converging Color Television Display System" and in the second application No. 15/73 invented by Josef Gross and others with the designation of the invention as "Self-Aligning Color Display System". Systems using this type of picture tube may produce an image with satisfactory alignment with greatly simplified alignment equipment, provided that a suitable deflection coil unit is also used in this system.

It is an object of the present invention to provide an improved deflection coil unit for use in a color image display system using electron guns in the same plane and on the same segment.

The present invention provides a deflection coil unit for use in a color image display system in which an image tube includes an electron gun for generating a plurality of in-line beams that sweep to produce a raster on the image surface of a picture tube. the distribution is circumferential with respect to the vertical deflection axis and changes as a function of the angular distance of the conductors from said axis, and the conductor density of each vertical deflection coil varies between the vertical and horizontal axes to produce a barrel-shaped field This deflection coil unit is characterized in that in the quadrants I, II, III, IV defined by the vertical and horizontal axes, the combined density of the vertical and horizontal deflection windings and the generated pad and barrel-shaped fields are adapted to balance the misalignment of said three beams to the non-aligned three rays along the vertical and horizontal axes of the image surface so as to provide a substantial alignment of the three rays at each point on the image surface when the rays sweep to form a raster.

59182

In one embodiment, the deflection coil unit includes a pair of both vertical and horizontal deflection coils wound annularly around a magnetically soft core. The distribution of the rotational density of this winding, in this unit, is chosen so that the density of the kdhtim is distributed in its smallest range between 25 and 45 ° from the vertical deflection axis, measured in both quarters in this deflection coil unit.

In another embodiment, this unit includes a pair of both vertical and horizontal saddle-type windings. The winding density distribution of the winding in this unit is selected so that the density distribution of the conductors is at its smallest in the range of 25 to 45 ° as measured by each quarter of this unit from the vertical deflection axis.

Reference is now made to the accompanying drawings, in which Figure 1 is a partial view of a color image display system incorporating a deflection coil unit according to the present invention; under the influence of a field, Fig. 4 illustrates the distribution of windings at the rear of an annular deflection coil unit when this unit is suitable for use in the system of Fig. 1, Fig. 5 illustrates linear distribution of windings in one quarter of Fig. 4, Fig. 6 illustrates saddles is a cross-sectional view of the windings of Fig. 6, Fig. 8 is an electrical schematic view of the winding shown in Figs. 6 and 7; .

Figure 1 is a sectional view of a color image display system incorporating a deflection coil unit in accordance with the present invention. My color television picture tube 10 includes a glass dome 11 in a vacuum. The front of this dome 11 is an image surface and the end face 12 inside it is provided with a plurality of red, green and blue phosphor portions 13, 13a and 13b placed thereon. In this tube is placed an aperture bag 14 for phosphor lashes 59182, which includes a number of apertures 15. These apertures 15 are thus not aligned with the phosphor portions so as to shield the electron beams so that parts of the electron beams passing through the apertures 15 colored phosphorus. At the other end of this calculator hood 11 is an electron beam cannon structure 16 which provides three electron beams on the same segment and located in a horizontal plane.

Located outside and around the glass dome 11 is located along its expanded portion therein a deflection coil unit 17 according to the present invention suitable for receiving current from a suitable source of sweep currents, not shown, and providing a magnetic field deflecting electronic paths horizontally and vertically to form swept raster on image surface. The deflection plane C, i.e. the plane from which the deflected rays which appear to appear on the image surface appear to appear to be located midway between the longitudinal axis of this deflection coil unit at right angles thereto. A detailed description of this deflection coil unit 17 will be given in connection with Figures 4 and 6.

Located behind the deflection coil unit 17, the neck portion of this glass sheath 11 has a static alignment apparatus 18. This static alignment apparatus 18 includes magnets whose positions are adjustable to compensate for any error in beam alignment and to cause these beams to be directed to a specific point in the center of this image surface. the rays are not deflected. A suitable static apparatus for use with the electron gun assembly 16 on the same line is already known from application No. 13/73, filed January 4, 1973, by Robert L Barbin, entitled "Magnetic Beam Arrangement Arrangement". Behind this beam alignment apparatus 18 is located a beam cleaning device 19, which is a conventional structure in order to bring these rays into contact with their corresponding parts of the color phosphorus.

Figure 2 illustrates the net field deflections of the deflection caused by the deflection coil unit of Figure 1. Although the non-uniformities of the horizontal and vertical magnetic fields vary from point to point along the longitudinal axis of this tube, the predominant net field of deflection is as shown in Figure 2.

59182

The deflection field for bending these radii in the horizontal direction provided by the pair of horizontal deflection coils is illustrated by the solid lines in the flow 21 as they travel in the vertical direction. It should now be noted that this magnetic field is in the shape of a pincushion, and the flux lines are convex if viewed from the center of the pattern. This field of horizontal deflection induces negative horizontal isotropic astigmatism for these electron beams. Isotropic astigmatism acts along the axis of deflection. Negative astigmatism along the horizontal axis of deflection tends to align horizontal rays on the same segment. Correspondingly, positive astigmatism along the vertical axis of deflection tends to align horizontal rays on the same segment. Figures 2 also show the lines of flux 22 representing a magnetic deflection field which deflects the rays in the vertical direction and produces this field in pairs of vertical deflection coils in the deflection coil unit 17. It should now be noted that the vertical deflection field is generally barrel shaped and the flux lines are concave seen from the center. The field of vertical deflection produces a positive vertical isotropic astigmatism to these rays. The purpose of providing such a specific deflection field, which will now be described, will be shown in connection with Figure 3.

Figure 3 illustrates the pattern of electron beam alignment in the system of Figure 1 under the influence of the deflection field of Figure 2. Fig. 3a illustrates the relative positions of the green, red and blue rays 20a, 20b and 20c, respectively, as they enter the deflection plane (plane C in Fig. 1) in this deflection coil unit as viewed from the image surface end of the picture tube.

Figure 3b illustrates in exaggerated form the position of alignment for these rays at the corner of the scanned raster and along the vertical and horizontal deflection axes 25 and 26, respectively. It should be noted that each electron beam illuminates a plurality of phosphor portions with a given color simultaneously. These phosphorus moieties are, of course, separated from each other, but this is not shown. Figure 3b illustrates the alignment of all rays to different areas on this image surface.

7 59182

The rays of green, red, and blue are in the center of the raster. This center alignment is accomplished by aligning the rays provided by the structure of the electron gun apparatus 16 and the operation of the static alignment apparatus 18 as shown in Figure 1. Along the horizontal deflection axis 26 the green, red and blue rays are not shown under-aligned, it is said along the axis and that their order is the same as what it is radiating in the plane of deflection as shown in Fig. 3a. This situation exists at both ends of the raster along the horizontal axis 26. It must now be understood that the under-alignment of the rays at the extremes of this horizontal axis decreases as a function of the distance from the center of the raster at which point these rays are aligned. Under-alignment of the horizontal rays is achieved by the negative, horizontal isotropic astigmatism 11a of the deflection coil unit, a feature not illustrated in Figure 2.

At the extremes of the vertical axis 25 in Fig. 3b the red, green, and blue rays are shown over-aligned, it is said that the blue and green rays intersect at some point such that on the image surface the blue and green rays are on opposite sides of their position in the plane of deflection . This over-alignment of the rays along the vertical axis decreases as a function of the distance from the center of this raster at which point the rays are aligned. The alignment of these rays along the vertical axis is accomplished by positive, vertical, isotropic astigmatism as a property of this deflection coil unit, which property is illustrated in Figure 2.

It has now been found according to the present invention that by measuring the relative amounts of positive and negative astigmatism in the deflection coils, a deflection field can be produced that causes horizontal rays on the same segment to substantially apply at the corners of this raster as at all other raster points, as illustrated in Figure 3b. . Using the deflection coil unit of the present invention, the astigmatism features not described above can be used to align the rays at substantially all points of the raster without the need for dynamic alignment correction equipment.

59182

In an ideal segment, the focusing deflection coil unit has a negative horizontal isotropic astigmatism and a positive vertical isotropic astigmatism and is free of anisotropic angular astigmatism, i.e., trapezoidal distortion. This quality of astigmatism is necessary to maintain the alignment of three horizontal rays on the same segment along the horizontal and vertical axis of deflection. Alignment will be performed simultaneously at the corners of this raster and, ideally, will result in the alignment of the rays at all points in the raster. As a practical matter, it has been defined that this ideal sequence focusing situation can only be realized with CRTs with a diagonal measurement of the CRT of about 35 an (14 inches) or less. In the case of picture tubes with a larger dimension parallel to the image surface, the focusing situation for the same series is not feasible and the trapezoidal distortion situation described in connection with Figs. 3b is then a consequence. When such a trapezoidal distortion exists, according to the present invention, positive and negative astigmatism must be dimensioned between the vertical and horizontal deflection windings by correctly selecting the winding ratio of the conductors so that the trapezoidal distortion is balanced by the axial error and the essential alignment situation can be points.

Substantial targeting, as the phrase is used herein, means a situation of targeting that is commercially acceptable. It is common practice for television set manufacturers to set a side alignment threshold in the design definitions for a particular television set. It is always desirable to keep misalignment as close to zero as possible, but in practice manufacturing variations make a zero-scale diffuse alignment virtually impossible to achieve. The design setpoint set by one manufacturer is that the scattered alignment of the beams, measured at a distance of 1.25 cm from the edges of the scanned grid, should be less than 1.3 ran (50 mils) with a picture tube with a diameter of 38 ° cm (15 inches). The design limit of this structure is increased for larger viewing surface cases and is approximately 1.6 ran (62 thousandths of an inch) in a picture tube with a viewing direction of 59,582 82 cm (25 inches). In practice, the manufacturing variations described above, in particular variations with respect to the color picture tube and deflection coil unit, result in the alignment error being distributed when moving from one receiver to another. Many receivers have a much smaller error than the 1.3 nm design amount. On the other side can understand the others receivers made from the same batch of parts on the same production line to the large number hajakohdistuksen. In receivers that are actually sold in the store, there have been cases where the spread alignment error is even greater than 3.2 nm. As used herein, the term "substantial alignment" means the amount of stray alignment that is not greater than 3.2 nm. The scattered alignment of these rays can ideally be observed as the difference between the superimposed red, blue, and green lines in the cross-grid pattern in the lines displayed on the picture tube when a suitable test mark is connected to the television receiver.

Figure 4 illustrates the distribution of the winding at the rear of the annular deflection coil unit according to the present invention and is suitable for use in the system of Figure 1. Figure 4 illustrates a cross-section of the distribution of windings with a small diameter portion, i.e. at the rear, in this deflection coil unit. In this section, the deflection coil units are located on and between the conductors of the outer layer, i.e. the second layer. It is now to be understood that at the front end, i.e. the large diameter end in this deflection coil unit, the conductors form only a single layer, and the conductors in the latter layer are interleaved directly between adjacent layers in the first layer. The vertical conductors 31 and the horizontal conductors 32 are wound annularly around the ferrite core 30. Derivatives 31 and 32 are active conductors providing a deflection field. Some of the return conductors 31a and 32a are shown on the outer circumference of the core 30. It should now be noted that these return conductors also extend around the entire deflection coil unit. The distribution of the conductor windings in all quarters I, II, III, IV bounded by the vertical and horizontal deflection axes 33 and 34, respectively, is similar, resulting in a symmetrical winding distribution of the deflection coil unit in all quarters. The vertical and horizontal conductors are generally interleaved as illustrated to produce the desired magnetic field properties of 10,591,82.

Figure 5 illustrates linearly the distribution of windings in one quarter of the deflection coil unit from Figure 4. According to the present invention, the relevant amounts of positive and negative astigmatism, as described above, can be proportionally measured between horizontal and vertical windings. Measuring the ratio of astigmatism between the windings by selecting the distribution of conductors as described, as shown in Figures 4 and 5, implements a special balancing to scatter alignment, it is said to to the corners of the raster. According to the present invention, the distribution of the windings in the deflection coil unit, the astigmatism of which is dimensioned between these windings, as described above, is further selected to have a minimum conductor density distribution in the range of 25-45 ° measured from the vertical deflection axis 33. In a particular embodiment, the minimum the area of the density distribution of the conductors is located around a certain point located 31 ° from the vertical deflection axis 33. It has been determined that when the region of the smallest density distribution of conductors is placed in this region, there is a substantial alignment of the rays at the corners of this raster as well as along the axes. It should be noted that the range of the minimum density distribution of the conductors depends on the type of picture tube selected and generally does not extend over the entire range between 25 ° and 45 ° from the vertical axis of deflection. As a result of this balancing of astigmatism and the placement of the smallest conductor density distribution in the area described above, there is a raster swept by a deflection coil unit that aligns the beams at substantially all points without the need for complex dynamic alignment correction equipment.

Fig. 6 illustrates a saddle-type winding suitable for use in the deflection coil unit of Fig. 1. For most purposes, it is known that a deflection coil unit using saddle-type coils may replace a deflection coil unit using ring-shaped coils in the case of a color television picture tube. The principles of the present invention are also applicable to saddle-type coils, as well as annular deflection coils 11 59182. Figure 6 consists of a saddle-type coil 35 of active magnetic field generating side chokes 36 connected at the front of the deflection coil unit by end turns containing transverse conductors 37 and then connected together at the rear of this deflection coil unit by transverse end coils shown in Figure 6. in the representation, the side conductors as well as the front and rear turns form a winding window with no conductors. As is known in the art, a saddle-type winding machine can be stopped after a preselected number of turns have been wound around the anchor of this winding, so that this winding can be provided with an electrical outlet. Such side outlets 39 are illustrated in Figure 6.

Fig. 7 is a cross-sectional view of the coil 35 of Fig. 6. The window 40 of this coil is not partially illustrated in Fig. 7. The cross-sectional portion of this coil shows conductors T1 and T2 illustrating two different side outlets taken out of the coil during its winding. As illustrated, a corresponding point is located between the two side outlets on either side of the windings 31 degrees away from the vertical deflection axis 33.

Figure 8 is an electrical schematic diagram of the winding shown in Figures 6 and 7. It can be seen that some of the conductors between the side outputs T1 and T2 are electrically bypassed during the common connection of the side outputs of this winding. Thus, even if the conductors are actually in place in this winding, making it easier to maintain its shape, they are electrically disconnected from this winding. Thus, in the region located between the angles 25-45 ° as measured from the vertical deflection axis, this deflection coil unit has the density of the distribution of the conductors providing the active field at its subsets. Thus, a deflection coil unit using saddle-type windings may be selected in the distribution of windings to scale the astigmatism between its windings in the same manner as described above and to have the smallest density of conductors in the range of angles between 25-45 ° from the vertical axis. A deflection coil unit using saddle-type deflection coils with electrically bypassed turns is described in U.S. Patent No. 3,588,566. However, the saddle-type turns described in this

Claims (6)

12,591,82 which, according to the present invention, further provide the desired balance for positive and negative astigmatism and have the lowest density of conductor turns, since the transverse cross-sectional area in these windings is between 25-45 ° from the vertical deflection axis. In a deflection coil unit using saddle-type coils, a pair of oppositely located vertical deflection coils are located 90 ° from a pair of opposing horizontal deflection coils within the anchor core of this deflection coil unit. Thus, although the side outlets in the desired range are shown for only one of the four deflection windings used in this deflection coil unit, it is to be understood that the other three windings are respectively provided with side outlets so that the conductor distribution density in each coil is in its smallest range of 25-45 ° calculated from the vertical deflection axis of this deflection coil unit. A deflection coil unit for use in a color image display system, wherein the image tube (10) includes an electron gun (16) for generating a plurality of in-line rays (20a, 20b, 20c) of the same level which scan to produce a raster on the image surface (12) of the image tube. wherein the deflection coil unit has vertical deflection coils and horizontal deflection coils to deflect the beams vertically and horizontally and the distribution of the conductors (31, 32) of each coil is symmetrical with respect to the vertical deflection axis (33) and changes the angular distance 31) varies between the vertical and horizontal shafts (33, 34) to create a barrel-shaped field (22), and the conductor density (32) of each horizontal deflection coil varies between the horizontal and vertical shafts (34, 33) to create a cushion-shaped field ( 21), characterized in that in the quadrilaterals defined by the vertical and horizontal axes (33, 34) (I, II, III, IV) the combined density of the vertical and horizontal deflection windings (31, 32) and the generated pad and barrel shaped fields are adapted to balance the misalignment of said three beams (20a, 20b, 20c) in the vicinity of the corners 13 591 82 of the image surface (12) aligning said three rays along the vertical and horizontal axes (25, 26) of the image surface (12) so as to provide a substantial alignment of the three rays at each point on the image surface (12) when the rays sweep to form a raster. A deflection coil unit according to claim 1, characterized in that the distribution of the windings and the generated fields are proportional to each other so as to cause over-alignment of the rays in the vicinity of the vertical deflection axes and under-alignment of the rays in the vicinity of the horizontal deflection axis. Deflection coil unit according to claim 1 or 2, characterized in that said combined density decreases to its minimum amount in an angular range of 25-45 ° from the vertical deflection axis. A deflection coil unit according to claim 3, characterized in that said minimum amount is about 30 ° from the vertical deflection axis in each quadrant of the deflection coil unit. An embodiment of an alternating energy system, including an image (10) of an electronic channel (16) for the purpose of flirting and forming a line, and having a line with a ligand (20a, 20b, 20c), for example. sweeping producer and raster head bildrörets bildskärm (12), varvid avlänkningsoket uppvisar vertikala avlänkningsspolar och horisontala avlänkningsspolar för av-länkande av stralar vertikat och horizontally and ledningsfördelningen av varje Spole (31) variation of the function of the ledge (31, 32) from the axis of the axis, and of the ledge (31) of the shadow of the vertical spindle of the vertical and horizontal axes (33, 34), so as to form the upper (22) of the ledge (32) ) with a horizontal or vertical axis with a horizontal and vertical axis (34, 33), the upper part of the upper (21) alstras, tt a combination of vertical and horizontal spindle spacing (31, 32)