DE1285516B - Static convergence device for color television receivers with color picture display tubes - Google Patents

Description

1 2

The invention relates to a static convergence The color picture tube has three electron beam

Device for color television receivers with color picture guns R, G and B for the colors red, green and

display tubes, the three electron beam guns blue on. Each of the magnetic devices 2 is with

have and provided in the three pole pieces symmetrically around a static convergence magnet 3,

the picture tube axis are arranged. 5 There is also a special magnet 4 on the side

It is the object of the invention to provide known sta- for the color blue. For these parts are table convergence devices for color television - already the most diverse arrangements pre-receivers, in particular the magnet assemblies have been hit. Basically, the Vorfür works the setting of the static convergence to the following direction: The simplify by the convergence, the magnetic fields generated by the currently most io magnets 3 act on used color picture tubes are used, which have a convergence pole pieces 5 a. This will create a mask and three lateral fields arranged in the shape of a triangle in view of the electron beams Have electron beam guns, by which the electron beams radially

According to the invention, the static convergence can be pushed. The laterally arranged device designed such that a first 15 magnet 4 for the color blue is used exclusively magnet arrangement with a resulting magnet to move the electron beam for the color blue lateral axis in a perpendicular to the picture tube axis borrowed. F i g. 2 shows the observer pole pieces generated by the plane outside the neck of the picture tube opposite one of the electron beams and perpendicular to the image convergence process in the vicinity of the tube axis, and its resulting «° center point of the luminescent screen. The displacement of the magnet axis about an electron beam parallel to the picture tube axis is rotatable through the static convergence axis and that, with regard to the picture device, has the effect that the luminous points generated by the electron tube axis symmetrically to the first magnet arrangement rays are arranged along a straight line along a second magnet arrangement, lines move, each forming an angle with each other also perpendicular comparable to the picture tube axis ² 5 of 120 °. This is indicated by the three vectors r, g shiftable and their resulting magnetic axis and O ₁ . By means of the magnet 4, the electron beam for the color blue is also rotatable along an axis about an axis parallel to the picture tube axis. shifted straight line passing through the on the

The convergence device according to the invention has specified _{vector O 1} , vector b _{2 which is perpendicular}

a simplified structure and can therefore be cheaper. With conventional convergence devices

can be produced and adjusted more easily. are therefore used to join the three elec-

Further details, advantages and training electrons in the central area of the luminescent screen

According to the invention result from the following four magnets used. These magnets work

Description. In the drawing, the invention is a longitudinal displacement of the electron beams

for example, shows 35 straight lines each having a fixed direction.

F i g. 1 schematically shows a section through a her- The position of the generated by the electron beams

The conventional convergence device on color television luminous dots is given by four vectors. in the

recipients, the example explained above are the four vectors

Fig. 2 an explanation of the operation of the gates r, g, O ₁ and b ₂ .

static convergence device of Fig. 1 at in 40 Fig. 3 shows a static convergence according to the invention

Observe vergence device near the center of the luminescent screen. It provides a schematic approach

th, light generated by the electron beams sees the neck of the picture tube, the one in the vicinity

score, the screen is cut open and in the direction of

FIG. 3 is a view corresponding to FIG. 1 for viewing the electron beam guns. Inner explanation the mode of operation of the 45 half of the neck 6 of the color picture tube according to the invention is a Y-shaped Convergence device, shield? intended. In the

F i g. 4 is a vector diagram of the distribution of the shield 7 and the tubular wall of the neck 6 magnetic field around a space limited in a point in space, pole pieces 8, 8 'and 8 "are pre-arranged magnetic dipole, seen each bent from two electrodes

F i g. 5 is a view of the metal sheet formed in the vicinity of the luminous 5o, the opposite center point of the screen in the case of a device according to FIG. 3 lie. In the end of the neck 6 of the color picture tube are occurring convergence ratios of the luminous electron beam guns 9, 9 'and 9 "such sub-items of the electron beams when not applied, that the electrons emanating from them dynamic convergence correction, each radiate between the two electrodes

6 shows a view corresponding to FIG. 5, in which 55 of a pole piece pass through. Up to here is the beder Influence of the pole pieces on the electron beam writing device with that in known color guns is considered, picture tubes completely identical. According to the invention has

7a and 7b, partially in section, a plan view, now the convergence device, a pair of permanent views and an elevation view of a static convergence magnet. One of these is plate-shaped Device according to one embodiment of the invention. 60 first magnet 10 outside the neck 6 of the formation and tube arranged opposite the pole piece 8. Of the

F i g. 8 a and 8 b a partially cut-second magnet 11 is symmetrical to the first magnet 10

crack and an enlarged partial view of a static trisch arranged with the center of the neck 6

Convergence device serves as a point of symmetry according to another Aus. The magnets 10 and 11

embodiment of the invention. 65 lie in one to the axis of the neck 6 of the picture tube

Fig. 1 shows a conventional convergence perpendicular plane and are each on the ends

Device with three around the neck 1 of a color image of support rods 12 and 13 arranged. You can

tube arranged around magnetic devices 2. so in the plane perpendicular to the picture tube axis

3 4

to be turned around. Moving the support rod 12 and magnet 11 and also the effect of the static

13 in the direction perpendicular to the axis of the neck 6, such as the convergence magnet and the side magnet for

which is indicated in FIG. 3 by the arrows, so the color blue by a single magnet 10

move the magnets 10 and 11 on the neck 6 is achieved.

to or from him. In Fig. 3 is the pole piece 8 5 The calculations presented above were made with

of the electron beam gun 9 for the color blue, which help assuming that a simple one

Pole piece 8 'of the electron beam gun 9' for the magnetic dipole at one point of space

Color green and the pole piece 8 "of the electron is arranged. In the construction used in practice

Beam cannon 9 "for the color red. According to FIG. 3, however, the pole pieces 8, 8 'and 8"

The basic effect of the magnets 10 and io a great influence on the distribution of the magnet-11 is now based on FIG. 4 described. Zu- tischen field. By changing the position of the next one tries to find a vector H in a magnet 10 and 11, for example by arranging point P, which can be a distance r from the center of these magnets in front of or behind the electron point 0 of the plate-shaped permanent magnets, beam guns namely, change the shape of the ellipse of the first magnet 10 or the second 15, as in FIG. 6 at A, B, C and D magnet 11 is removed. Assume that this is stated. F i g. 6 shows the effect of the magnetic moment of magnets 10 and 11 M ist, magnet 10. The best position of magnet 10 is that, then the magnetic potential U is at point P at which the ellipse assumes a particularly favorable shape. In general, an ellipse becomes as shown in 1 (MP) 1 M cos Θ ^B0 F i g. 6, ß, shown form be particularly favorable because

^ ~ "7 3— ~ 7 '- I ' (1) Error in the manufacture of the electron beam

^4π Λ> ^r 4πμ ₀ r canons less in the lateral than in the radial

where Θ is the angle between the direction of the direction affect.

magnetic moment M and the direction of the practical embodiments of the vector r and μ _{0 is} the permeability. From this, 25 invention will be described. The shapes of the components H _{r of} the magnetic field H in the neck 6, the pole pieces 8, 8 'and 8 ", the electron direction of the vector r and as component Rq in beam guns 9, 9' and 9" and the shield 7 Direction Θ the following equations: remain the same as those already given by

"F i g. 3 were described. Plastic housing 14

H _r = _ - = -JL 2MmaV __ ^ ^ _{30 den except} h _a lb of the parts of the wall of the

dr 4πμ ₀ r ^s neck 6 provided that the pole pieces 8,8 'and 8 "

opposite. This creates two each other

^m ρ) opposite rooms. Within these two

4 7τμ ₀ r ³ spaces become U-shaped dynamic convergence

35 yokes 15 and 16 and also the disk-shaped ones. By eliminating Θ from equations (2), static convergence permanent magnets, namely and (3), are obtained as the location of the vector H of the magnets 10 and 11, which are rotated under the magnets 10 and 11 according to the invention brought. Since the dynamic convergence yokes 15

₂ and 16, however, not with the present invention

i = 1 (4) 40 have to do directly, they do not get any closer

(2Kf K ² described. The two disk-shaped magnets

wherein 10 and 11 are corrugated on their outer circumference,

_ 1 st so that they can easily be turned by hand

"" ^ _n 7 "~~ 3 'can. The magnets 10 and 11 are diametrical

^μ ° 45 magnetized. They are rotatable by support shafts 17

Equation (4) gives an ellipse whose major axis and 18 are held. The support shafts 17 and 18 are

is twice as large as its minor axis. An elec- tric plugged into support parts 19 and 20, respectively

electron beam at point P will therefore consist of two magnetically neutral plates depending on the

from the angle Θ an elliptical movement be arranged parallel to one another. The magnets

to write. If now such a movement at 5 ° 10 and 11 can be moved up and down,

a device according to FIG. 3 applied, L-shaped ferromagnetic plates 21 and 22 are attached

one has a convergence effect according to FIG. 5 received. the rear ends of the support parts 19 and 20

Dynamic convergence correction is not required. These ferromagnetic plates 21 and 21 are used, so the luminous points R, G and B in 22 are able to bridge the N and S poles of the per-dependence on the angle Θ from their position magnets and thus create a gap R, G and B moved away. The shielding effect is generated when the permanent luminous points R and G first come together at a point W as far as possible from the pole pieces. This can be achieved by moving away, ie when a convergence correction magnet 11 rotates and moves it up or down. for not required or only to a very limited extent - the closer the magnet 11 is to the neck of the dye 60 Hch. In Fig. 7 is a convergence plate 23 with a picture tube, the greater the displacement of the luminous points caused by it dynamic convergence devices 24. Then, further a purity magnet 25 and a deflection of the luminous point B is brought to the point W , yoke 26. The correction is made by rotation and by rotating the magnet 10 and moving it. On the up or down movement of the magnets 10 and 11 in this way, according to the invention, the effect that 65 is brought about.

in conventional devices by separate A further embodiment of the invention is

static convergence magnets for the colors red and now with reference to FIG. 8 a and 8 b. In

Green was achieved, through the effect of a single Fig. 8a, the shapes of the neck 6, the ab-

shielding 7, the pole pieces 8, 8 'and 8 "and the electron guns 9, 9' and 9" with the Hand of Fig. 3 parts described identical. Dynamic convergence yokes 15 and 16 correspond the convergence yokes of FIG. 6 and are not described in detail. The convergence yoke 15 is seated part of the wall of the neck 6 opposite the pole piece 8, and the convergence yoke 16 sits on the opposite side.

A permanent magnet 27 is arranged opposite the pole piece 8. Symmetrical to the permanent magnet 27 sits a permanent magnet 28, the axis of the neck of the picture tube as the axis of symmetry serves. The permanent magnets 27 and 28 are cylindrical and their axes are on that of the neck 6 perpendicular. Each cylinder is divided into two sections by a plane perpendicular to the neck divided, one of which is magnetized with N polarity and the other with S polarity. Support bars 29 and 30 are attached to the ends of permanent magnets 27 and 28, respectively. The permanent magnets 27 and 28 can be rotated by turntables 31 and 32 attached to the front ends of the support bars 29 and 30 seats.

The permanent magnets 27 and 28 are inserted in plastic holders 33 and 34. These are each tubular and otherwise designed as a right-angled parallelepiped. Here are the permanent magnets 27 and 28 in permanent contact with plate-shaped pieces of soft iron 35 and 36, which are parts of one of the Inner walls of the plastic holders 33 and 34, respectively. The permanent magnets 27 and 28 are rotated in constant contact with the soft iron pieces 35 and 36 moved. The plastic holders 33 and 34 are moves perpendicular to the axis of the neck 6. The permanent magnets 27 and 28 make this movement with.

The soft iron pieces 35 and 36 can be made of any magnetic material with little Residual magnetism exist.

In terms of its function, the embodiment according to FIG. 8 basically agrees with the embodiment according to FIG. 3. If, for example, the permanent magnets 27 and 28 are in such a way that their S poles are in Are in contact with the soft iron pieces 35 and 36, then the opposite parts of the Pieces of soft iron magnetized in S-polarity. This corresponds to the arrangement of the permanent magnets, namely the magnets 10 and 11 according to FIG. 3. Are the permanent magnets 27 and 28 so that the boundary line between their N and S poles is in contact with the soft iron pieces 35 and 36, respectively, then will these pieces of soft iron are not magnetized at all and there is no effect. In this case correspond the permanent magnets 27 and 28 the 90 ° rotated magnets 10 and 11 of Fig. 3, Es is therefore possible by suitable rotation of the permanent magnets 27 and 28, the same effect can be achieved, as in FIG. 3, by rotating the magnets 10 and 11.

In the device according to FIG. 8, the axes of rotation of the permanent magnets 27 and 28 are opposite the axes of rotation of Fig. 3 turned by 90 °. As a result, the permanent magnets 27 and 28 be rotated more easily.

If the soft iron pieces 35 and 36 are too wide, the N and S poles of the permanent magnets 27 become and 28 shorted through it. This results in decreased sensitivity. Are the soft iron pieces too narrow, the magnetic field becomes weak in the radial direction, resulting in a flat ellipse Has.

As described above, the "static convergence" and the "lateral shifting of the Electron beam for the color blue «can be brought about by only two magnets, while for it four magnets were required in the conventional devices.

Claims (6)

Patent claims: 1. Static convergence device for color television receivers with color display tubes, which have three electron guns and in which three pole pieces are symmetrical around the Picture tube axis are arranged, thereby characterized in that a first magnet arrangement (10,27) with a resulting magnet axis in a plane perpendicular to the picture tube axis outside the picture tube neck (6) one (8) of the pole pieces (8, 8 ', 8 ") is opposite and displaceable perpendicular to the picture tube axis and the resulting magnet axis is rotatable about an axis parallel to the picture tube axis and that symmetrically to the first magnet arrangement (10, 27) with respect to the picture tube axis second magnet arrangement (11, 28) is arranged, which is also displaceable perpendicular to the picture tube axis and its resulting magnetic axis also around an axis parallel to the picture tube Axis is rotatable. 2. Device according to claim 1, characterized in that the magnets (10, 11; 27, 28) the magnet assemblies are magnetized diametrically. 3. Apparatus according to claim 1 or 2, characterized in that two strip-like Magnet parts (35,36) are provided, their magnetization by the rotation of the two Magnets (27, 28) is variable and made of a magnetic material with low residual magnetism exist that the magnet parts (35, 36) are arranged perpendicular to the picture tube axis and together with the magnets (27, 28) perpendicular to the picture tube axis are movable and that constantly one end of the magnet parts (35, 36) with the magnet (27, 28) is in contact (Fig. 8). 4. Apparatus according to claim 3, characterized in that the two magnets (27, 28) are cylindrical, so that one half cylinder is magnetized as N-PoI and the other as S-PoI is that the cylinders are rotatable about their own axes and that each of the strip-like Magnet parts (35,36) with part of the outer surface of one of the cylindrical magnets (27, 28) is in contact. 5. Apparatus according to claim 1, characterized in that the magnets (10, 11) are disc-shaped are formed and magnetized diametrically and that they are each rotatable on support shafts (17, 18), which are inserted through guide rods (19, 20) made of magnetically neutral material are, by means of which the two magnets (10, 11) can be displaced in a plane perpendicular to the picture tube axis are (Fig. 7). 6. Apparatus according to claim 5, characterized in that for short-circuiting the N and S-PoIe of the magnets (10, 11) at the end of the guide rods (19, 20) Short-circuiting plates (21, 22) are provided. 1 sheet of drawings 809 648/1489