JP3141983B2 - Deflection device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a deflection device mounted on a color cathode ray tube having an in-line array of electron guns.

[0002]

2. Description of the Related Art In recent years, a color cathode-ray tube having an in-line array of electron guns has an in-line surface for three electron beams in an in-line array, and a non-uniform pin for a horizontal deflection magnetic field perpendicular thereto. It is well known that a self-convergence type deflection device is installed and used to obtain a convergence of three electron beams by generating a cushion magnetic field and a barrel magnetic field for a vertical deflection magnetic field parallel thereto. It is a fact.

On the other hand, as the horizontal deflection frequency becomes higher, the non-uniformity of the deflection magnetic field causes the center beam (G) and the side beams (R, B) of the three electron beams to move between them. A coma-free type deflecting device that is configured to be able to correct the generated convergence shift, so-called coma aberration, on the deflecting device side is often used.

[0004] In general, a coma-free type deflecting device has a coma correction coil formed by winding a pair of U-shaped cores or E-shaped cores around legs, symmetrically in the left-right or up-down direction at the rear of the deflecting device. By disposing a vertical deflection current through the coma correction coil, coma aberration (so-called VCR) in which the center beam G is shifted in the vertical direction with respect to the side beams R and B on the vertical axis as shown in FIG. Then, it is configured to obtain a normal pattern as shown in FIG.

The distortion generated in the self-convergence type deflecting device is standard for patterns a and b as shown in FIG. Then, the left and right raster distortion as shown by the pattern a could be corrected by providing a correction mechanism on the deflection circuit side combined with the deflection device.

However, the vertical raster distortion as shown by the pattern b has to be as close to 0% as possible on the deflecting device side.

On the other hand, as the resolution of the color cathode ray tube is increased, the screen is enlarged and flattened (FS), and a deflecting device with further improved convergence characteristics and raster distortion characteristics is strongly demanded. In a convergence type deflection device or a coma-free type deflection device, the characteristics of the deflection device itself can be improved to some extent by various means.

[0008]

However, even if it is possible to obtain a deflecting device having a considerably improved characteristic, the deflecting device and the color cathode ray tube are assembled as a set for practical use. It is inevitable that unbalance will occur in the vertical and horizontal raster distortion.
There has been a problem that the characteristics of the deflecting device are rather deteriorated by the use of the TC. This is because color cathode ray tubes and deflectors have variations in characteristics at the time of manufacture.
This is because these variations cause misconvergence during TC conversion.

That is, for example, when the characteristics at the time of manufacturing a color cathode ray tube vary and the mechanical center of the electron gun and the center of the deflecting magnetic field are displaced from each other, FIGS.
A convergence error occurs as shown in (b) 1, 2, 3, and 4. Therefore, in order to correct the misconvergence, a swing operation of adjusting the convergence by swinging the screen side of the deflecting device up and down and left and right has been performed. Correction was possible by matching the mechanical center of the electron gun inside the color cathode ray tube with the center of the magnetic field of the deflecting device. Also, convergence errors indicated by 1, 2, and 3 can be arbitrarily corrected by a relatively simple correction method.

However, when the head is swung up and down, FIG.
Upper and lower trapezoidal distortions as shown in FIGS. 7A and 7B, and left and right trapezoidal distortions as shown in FIGS. Here, the upper and lower trapezoidal distortions shown in FIGS. 8A and 8B can be arbitrarily corrected by a correction mechanism provided on the circuit side of the ITC set, so that there is no comparative problem. However, FIG.
It is extremely difficult to correct left and right trapezoidal distortions as shown in FIG. 2B because the correction mechanism is not on the circuit side of the ITC set and the upper and lower trapezoidal distortions are originally as close as possible to 0%.

On the other hand, the convergence error shown at 4 in FIG. 9 (b) is a phenomenon in which the electron beam R (B) is shifted in the vertical direction outward or inward with respect to the electron beam B (R) on the vertical axis. In general, this is called a V tilt, and the cause is a deviation between the mechanical center of the electron gun and the center of the deflection magnetic field as described above. If the cause is on the color cathode ray tube side, as shown in FIG. 4, the mechanical center of the electron gun shifts in the left-right direction, so that the mechanical center of the electron gun coincides with the center of the deflection magnetic field. Disappears. If the cause is on the deflection device side and the core and the vertical deflection coil are shifted left and right, the center of the deflection magnetic field is shifted from the normal position as shown in FIG. Had an imbalance.

Conventionally, the convergence error caused by the displacement between the mechanical center of the electron gun and the center of the deflecting magnetic field is conventionally corrected by the swinging operation of the deflecting device or connected to both ends of a pair of right and left vertical deflecting coils. The correction has been made by changing the resistance value of the damping resistor and changing the vertical deflection current flowing through the left and right vertical deflection coils. However, even if the convergence error caused by the displacement between the mechanical center of the electron gun and the center of the deflecting magnetic field is corrected by the above-described correction method, the trapezoidal distortion shown in FIGS. 7A and 7B is reversed. In addition to this, it is extremely difficult to correct only the left and right trapezoidal distortion alone. The reason for this is that in both the swinging operation and the adjustment method for changing the vertical deflection current flowing in the left and right vertical deflection coils, the left and right strengths of the vertical deflection magnetic field with respect to the beam are unbalanced. This is because left and right trapezoidal distortion is caused.

As described above, in the conventional deflecting device, the swinging operation is very effective in terms of convergence correction. However, in terms of correcting the left and right trapezoidal distortion, the swinging operation has rather become a factor of deteriorating the characteristics. Therefore, it has been extremely difficult to satisfy the convergence and to correct the right and left raster distortions so as not to be unbalanced.

An object of the present invention is to solve the above-mentioned difficulties by simple means, and to achieve convergence and convergence caused by ITC.
It is an object of the present invention to provide a deflecting device capable of correcting an error and correcting left and right trapezoidal distortion caused by a swing operation of the deflecting device.

[0015]

A deflecting device comprising at least a pair of upper and lower clad horizontal deflection coils and a pair of left and right clad vertical deflection coils and mounted on a color cathode ray tube having an inline array of electron guns. , Upper leg portions 2L, 2R and middle leg portions 3L, 3 of a pair of E-shaped cores 1 and 1A.
R and lower legs 4L and 4R, respectively.
L, 2R and the lower leg portions 4L, 4R, a pincushion-type magnetic field in the same direction as the vertical deflection magnetic field is applied to the intermediate leg portions 3L, 3R.
Coma correction coils 6L and 6R wound so as to generate a barrel-type magnetic field in the direction opposite to the vertical deflection magnetic field are connected in series, and a pair of left and right vertical deflection coils 5L and 5L connected in series are connected.
5R, 5L, 5R connected in series and connected symmetrically to the rear of the deflection device, and connected in series.
Is connected in parallel with a variable resistor VR1 for changing the current flowing in each of the left and right vertical deflection coils 5L and 5R, and the correction coils 6L and 6R connected in series change the current flowing in the left and right correction coils 6L and 6R. Variable resistor VR
2 are connected in parallel to correct the left and right trapezoidal distortion and the convergence error at the same time.

[0016]

The current flowing in the left and right vertical deflection coils 5L and 5R is changed by the variable resistor VR1 connected in parallel to the pair of club type vertical deflection coils 5L and 5R, so that the right and left trapezoidal distortion caused by the center deviation of the vertical deflection magnetic field is reduced. Will be corrected. The convergence on the vertical axis, which is worsened by changing the current flowing through the left and right vertical deflection coils 5L and 5R, is caused by the coma correction coils 6L and 6R wound on the E-shaped cores 4 and 4A by the variable resistor VR2. Is corrected by changing the current flowing through the rectifier, and the left and right trapezoidal distortion is corrected without adversely affecting the convergence characteristics as a whole.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings. FIG. 1 is an explanatory diagram showing the configuration of a coma correction coil used in the deflection device according to the present invention, and FIG. 2 is a circuit diagram showing the configuration of the deflection device according to the present invention. In the figure, reference numerals 5L and 5R denote a pair of left and right club-type vertical deflection coils, and damping resistors R3 and R are connected to the vertical deflection coils 5L and 5R connected in series.
4 and a series circuit of the variable resistor VR1 are connected in parallel. This variable resistor VR1 is composed of left and right vertical deflection coils 5
This is a variable resistor for changing the vertical deflection current flowing through L and 5R. 1, 1A is a pair of left and right E-shaped cores, each of which has upper legs 2L, 2R and middle legs 3L, 3L.
Coil 2LC, 2R on R and lower leg 4L, 4R
C, 3LC, 3RC, 4LC, and 4RC are wound to form a pair of left and right frame correction coils 6L and 6R. The left and right frame correction coils 6L and 6R are connected in series.
A series circuit of damping resistors R1, R2 and a variable resistor VR2 is connected in parallel to the series-connected coma correction coils 6L, 6R. The variable resistor VR2 is a variable resistor for changing the vertical deflection current flowing through the left and right frame correction coils 6L and 6R.

The pair of frame correction coils 6L, 6L
As shown in FIG. 3, the coil of each leg constituting the R, a barrel type magnetic field indicated by a dotted line in the direction opposite to the vertical deflection magnetic field between the middle legs 3L and 3R, and the upper legs 2L and 2R It is wound between the lower leg portions 4L and 4R so as to generate a six-pole magnetic field by generating a pincushion-type magnetic field indicated by a solid line in the same direction as the vertical deflection magnetic field.

Since the deflection device of the present invention is configured as described above, the vertical deflection current flowing through the left frame correction coil 6L and the right frame correction coil 6R can be changed by adjusting the variable resistor VR2. , 4 in FIG.
Can correct the V tilt of the convergence error as shown in FIG.

The pair of frame correction coils 6L, 6L
Since R is disposed at the rear of the deflecting device, it is possible not only to make a large correction with a small change but also to make the vertical deflection magnetic field itself unbalanced, so that V is not affected by raster distortion. It is possible to perform tilt correction.

As described above, according to the present invention, the right and left trapezoidal distortion is corrected by changing the vertical deflection current flowing through the left and right vertical deflection coils, and the right and left trapezoidal distortion is changed by changing the vertical deflection current flowing through the left and right coma correction coils. Since the V tilt caused by the correction is corrected, it is possible to obtain a deflection device capable of simultaneously correcting the left and right trapezoidal distortion and the V tilt.

[0022]

According to the deflecting device of the present invention, the trapezoidal distortion caused by various causes can be easily corrected by simple means, and the convergence error which occurs in the correction of the trapezoidal distortion can be eliminated. An inexpensive deflecting device that can be corrected at the same time is obtained, and the adjustment workability in ITC is greatly improved.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing a configuration of a coma correction coil used in a deflection device of the present invention.

FIG. 2 is a circuit diagram showing a configuration of a deflection device of the present invention.

FIG. 3 is an explanatory diagram of a magnetic field generated by a coma correction coil according to the present invention.

FIG. 4 is an explanatory diagram showing a mechanical center shift of the electron gun of the color cathode ray tube.

FIG. 5 is an explanatory diagram showing a center deviation of a deflection magnetic field due to a cause on the deflection device side.

FIG. 6 is an explanatory diagram showing general raster distortion.

FIG. 7 is an explanatory diagram showing left-right trapezoidal distortion.

FIG. 8 is an explanatory diagram showing upper and lower trapezoidal distortion.

FIG. 9 is an explanatory diagram showing a convergence error.

FIG. 10 is an explanatory diagram showing coma aberration.

FIG. 11 is an explanatory diagram showing a normal pattern.

[Explanation of symbols]

1, 1A E-shaped core 2L, 2R Upper leg 2LC, 2RC, 3LC, 3RC, 4LC, 4RC Coil 3L, 3R Middle leg 4L, 4R Lower leg 5L, 5R Kura type vertical deflection coil 6L, 6R Frame correction Coil R, G, B Electron beam R1, R2, R3, R4 Damping resistor VR1, VR2 Variable resistor

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H01J 29/76 H04N 3/23 H04N 9/20 H04N 9/28

Claims (1)

(57) [Claims] At least a pair of upper and lower club-type horizontal deflection coils and a pair of left and right club-type vertical deflection coils are provided,
A deflector mounted on a color cathode ray tube having an in-line array of electron guns, comprising a pair of E-shaped cores 1 and 1A, upper legs 2L and 2R, middle legs 3L and 3R, and lower legs 4L and 4R. A pincushion-type magnetic field in the same direction as the vertical deflection magnetic field between the upper legs 2L and 2R and the lower legs 4L and 4R, and a barrel in the opposite direction to the vertical deflection magnetic field between the intermediate legs 3L and 3R. A series of coma correction coils 6L and 6R wound to generate a mold magnetic field are connected in series, connected in series to the pair of left and right vertical deflection coils 5L and 5R connected in series, and disposed symmetrically at the rear of the deflection device. To the vertical deflection coils 5L and 5R connected in series, variable resistors VR1 for changing currents flowing in the left and right vertical deflection coils 5L and 5R are connected in parallel, and the correction coils 6L and 6 connected in series are connected. Left and right correction coils 6L, by parallel connection of variable resistor VR2 to vary the current flowing through the 6R, deflection apparatus characterized by being configured so as to correct the left and right trapezoidal distortion and convergence errors at the same time to.