JP3637549B2 - CRT output position automatic adjustment device and CRT output position adjustment method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
[0002]
The present invention relates to a method for adjusting an image output position using a centering magnet, and more specifically, an image is output to an appropriate position using a centering magnet in a manufacturing process of a CRT (cathode ray tube) or an apparatus equipped with a CRT. The present invention relates to an improvement of an adjustment method for making the center of an image coincide with the center of a CRT screen.
[Prior art]
[0003]
In general, CRT has characteristic variation, and variation occurs in the output position (position on the CRT screen on which the image pattern is displayed). Therefore, the image pattern is output, and the center of the image pattern is displayed on the CRT screen. That is, it is necessary to make adjustment so as to coincide with the center of the phosphor screen.
[0004]
Therefore, in this type of CRT, as shown in FIG. 8, the deflection yoke Y attached to the neck portion includes centering magnets Ma and Mb, and the image output position is adjusted by the centering magnets Ma and Mb. It has been broken. Although the illustrated CRT is called a flat cathode ray tube, the same applies to a normal non-flat type cathode ray tube.
[0005]
The centering magnets Ma and Mb are two thin plate magnets that are rotatably mounted, and the direction of the synthetic magnetic field formed by the two magnets Ma and Mb by rotating the centering magnets Ma and Mb. And the size can be changed.
[0006]
FIG. 9 schematically shows the movement of the electron beam in the flat cathode ray tube. The electron beam passes through the combined magnetic field of the centering magnets Ma and Mb, reaches the CRT screen, and becomes visible light on the CRT screen. It shows a state where the video is displayed after being converted.
[0007]
When a CRT electron beam passes through this combined magnetic field, Lorentz force acts on the electron beam according to Fleming's left-hand rule. Therefore, by adjusting the direction and magnitude of the synthetic magnetic field and correcting the trajectory of the electron beam, the image can be displayed at an appropriate position on the CRT screen. That is, it is possible to correct the variation in the characteristic image output position of the CRT.
[0008]
10 and 11 show a state in which force vectors V ′ and V act on an image on a CRT screen by the electron beam in the cathode ray tube being affected by the magnetic field of the centering magnet M. FIG. .
[0009]
A screen SC ′ in FIG. 10 is a CRT screen in a normal cathode ray tube, and is arranged so that the traveling direction of the electron beam becomes a perpendicular line. On the other hand, the screen SC is a CRT screen in a flat cathode ray tube and is arranged so as to form an angle of θ with the screen SC ′, and the traveling direction of the electron beam and the perpendicular direction of the screen SC form an angle of θ.
[0010]
For this reason, if the direction of the magnetic field M of the centering magnet is as shown in the figure, the force vector V ′ acts on the screen SC ′ in the case of a normal cathode ray tube due to the Lorentz force, In the case of a flat cathode ray tube, a force vector V obtained by projecting the force vector V ′ onto the screen SC acts.
[0011]
Here, the force vector V ′ and the force vector V have the same x-axis direction component, but the y-axis direction component of the force vector V is 1 / of the y′-axis direction component of the force vector V ′. It is cos θ times. That is, the component of the force vector V in the y-axis direction and the component of the force vector V ′ in the y′-axis direction do not match, and the relationship is determined by the inclination θ. FIG. 11 is a view of FIG. 10 viewed from the direction of the arrow, and shows the relationship between the y ′ direction component of V ′ and the y direction component of V.
[0012]
In this way, when the centering magnet is rotated, in the case of a normal cathode ray tube, the locus of the force vector V draws a circle, but in the case of a flat cathode ray tube, an elliptical activation is drawn.
[0013]
Using such a principle, in the manufacturing process of a CRT or a product equipped with a CRT, an image pattern is displayed on the CRT screen, and an operator uses a screwdriver or the like while viewing the pattern to display the centering magnet Ma. , Mb was rotated to adjust the image output position.
[Problems to be solved by the invention]
[0014]
However, even when only one centering magnet is moved, the trajectory of the image pattern on the CRT screen draws a circular or elliptical trajectory, and the image pattern output position is the combined magnetic field of the two centering magnets. Therefore, the two centering magnets must be moved relative to each other for adjustment.
[0015]
For this reason, it is not easy for the operator to adjust the image output position on the CRT screen by moving the two centering magnets while viewing the image pattern that has been output. Was needed.
[0016]
The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a method for adjusting the image output position by a centering magnet according to a certain rule, and to automatically adjust the image output position.
[Means for Solving the Problems]
[0017]
The automatic adjustment apparatus for the CRT image output position according to claim 1, wherein each centering magnet is sequentially rotated so that both poles of both centering magnets coincide with each other, whereby a Lorentz force force vector acting on the electron beam by these magnets is obtained. Are set in the same direction, and further, the respective centering magnets are rotated 90 degrees in opposite directions, and the polarities of the respective centering magnets are set in opposite directions so that the two vectors are opposite to each other . By rotating the centering magnet in the same direction and by the same angle, the direction of the resultant force of both vectors is made to coincide with the direction of the target on the CRT screen, and the both centering magnets are rotated in the opposite directions by the same angle. The magnitude of the resultant force vector Is adjusted to match the output position of the image pattern with the target.
[0018]
The automatic adjustment apparatus for CRT image position described in claim 2 is the automatic adjustment apparatus for CRT image position according to the present invention described in claim 1, wherein the diagonal intersection or the center of gravity of the image pattern coincides with the target position. It is said.
[0019]
According to a third aspect of the present invention, there is provided the CRT output position automatic adjusting device according to the present invention, wherein the Lorentz forces of the centering magnets are opposite to each other. Before rotating both magnets, each centering magnet is rotated in order, and when the locus of the image pattern by each rotation reaches the apex position, each rotation is stopped, so that each centering magnet is In addition, a magnetic force relationship in which the directions of the force vectors of the respective Lorentz forces coincide with each other is formed.
[0020]
According to a fourth aspect of the present invention, there is provided an automatic adjustment apparatus for a CRT output position according to the present invention, wherein the image pattern size is minimized and the image pattern is minimized. The pattern trajectory is recognized.
[0021]
According to the method for adjusting the CRT image output position described in claim 5, by rotating each centering magnet sequentially and matching both poles of both centering magnets, the force vector of the Lorentz force acting on the electron beam by these magnets is obtained. In the same direction, each centering magnet is rotated 90 degrees in the opposite direction, and the polarities of the respective centering magnets are set in the opposite directions so that both vectors are opposite to each other. By rotating the magnet in the same direction and by the same angle, the direction of the resultant force of both vectors is made to coincide with the direction of the target on the CRT screen, and further, both the centering magnets are rotated in the opposite directions by the same angle. Adjust the magnitude of the resultant force vector By Rukoto, characterized in that to match the image output position of the image pattern onto a target.
[0022]
The method for adjusting the CRT image output position described in claim 6 is the method for adjusting the CRT image output position described in claim 5 , wherein a diagonal intersection or a center of gravity of the image pattern is set as the image pattern position, and this position is defined as This is a method of matching the target position.
[0023]
The method for adjusting the CRT image output position described in claim 7 is the method for adjusting the CRT image output position described in claim 5 or 6 so that the Lorentz forces by the respective centering magnets are opposite to each other. Before rotating both magnets, each centering magnet is rotated in order, and when the trajectory of the image pattern by each rotation reaches the apex position, each rotation is stopped , The magnetic force relationship by which the direction of the force vector by the Lorentz force of this corresponds is characterized.
[0024]
The CRT output position adjustment method according to claim 8 is the CRT output position adjustment method according to claim 7, wherein the image pattern trajectory is set so that the size of the image pattern is minimized. This is a method of creating a certain magnetic force relationship between the centering magnets.
[0025]
The CRT image output position adjustment method described in claim 9 is the CRT image output position adjustment method according to any one of claims 5 to 8, wherein an outer peripheral portion of the centering magnet is formed in a gear shape. In adjusting the image output position, the adjustment gear is engaged with the outer periphery of the centering magnet, and the rotation of the motor is transmitted to the centering magnet via the adjustment gear to adjust the image output position. It is.
[0026]
The CRT in claims 1 to 9 means a cathode-ray tube, and includes both a flat cathode ray tube and a non-flat type ordinary cathode ray tube.
DETAILED DESCRIPTION OF THE INVENTION
[0027]
An embodiment of the CRT image position adjustment method according to the present invention will be described with reference to FIG. FIGS. 1 to 3 (a) to (h) are diagrams showing the image appearance on the CRT phosphor screen and the positional relationship between the centering magnets Ma and Mb during adjustment. The illustrated centering magnets Ma and Mb are those seen from the direction of the electron gun.
[0028]
First, an image pattern that can confirm the output state of the entire screen, that is, a rectangular (rectangular) image pattern is displayed on the CRT. This image pattern P is set to the smallest state both vertically and horizontally by adjusting the volumes of V (vertical size), H (horizontal size), and K (keystone). As a result, when adjusting the image output position, the image pattern P is prevented from being out of the frame on the CRT screen, and the locus of the image pattern P is easily recognized. This is shown in FIG.
[0029]
Next, one of the centering magnets Ma is rotated to observe the locus of the image pattern P. At this time, the other centering magnet Mb is fixed. Since the image pattern P moves while drawing a circular or elliptical orbit, the centering magnet Ma is adjusted so that the image pattern P is positioned at the apex of the orbit. This state is shown in FIG. Here, since the vertex is above the trajectory, the south pole of the centering magnet Ma is in the right direction.
[0030]
Here, when the trajectory of the image pattern P is observed, the barycentric point of the image pattern P is set as the position of the image pattern P, and the trajectory of the barycentric point is adopted as the trajectory of the image pattern P. When the image pattern P is rectangular, the diagonal intersection can be used as the position of the image pattern P.
[0031]
Note that a point called a vertex does not exist in a circular trajectory or the like, but a feature point that can be specified on the trajectory of the video pattern is called a vertex for convenience. Here, it is called a vertex as a feature point that can identify the position on the uppermost side of the trajectory.
[0032]
When this adjustment is finished, the centering magnet Ma is fixed and the other centering magnet Mb is rotated. At this time, as in the case of the centering magnet Ma, the centering magnet Mb is adjusted so that the image pattern P is positioned at the apex of the circle or elliptical orbit of the image pattern P. This situation is shown in FIG. After the adjustment, the S pole of the centering magnet Mb is also in the right direction.
[0033]
In this way, by adjusting the centering magnets Ma and Mb, the polarities of the centering magnets Ma and Mb can be matched. That is, the directions of the magnetic force vectors from the north pole to the south pole of the centering magnets Ma and Mb coincide with each other, and the relative positional relationship between the two magnetic force vectors can be grasped.
[0034]
Next, by rotating each centering magnet Ma, Mb by 90 degrees in the opposite direction, the relative angle between the centering magnets can be 180 degrees, that is, the polarity can be reversed. FIG. 2D shows this state, and the vectors Va and Vb shown in the figure are the forces acting on the image pattern P on the CRT screen by the centering magnets Ma and Mb, respectively. Vector. That is, the Lorentz force acting on the electron beam in the magnetic field formed by the centering magnets Ma and Mb is expressed as force vectors Va and Vb acting on the image pattern P on the CRT screen.
[0035]
Since both the centering magnets Ma and Mb have opposite polarities, the vectors Va and Vb are also vectors having the same magnitude in the opposite directions. The vectors Va and Vb cancel each other, and the image pattern P has a force. No vector is acting.
[0036]
In this state, even if the centering magnets Ma and Mb are both rotated in the same direction by the same angle, the relative relationship between the vectors Va and Vb does not change. The directions of the vectors Va and Vb change. In this way, the direction to the target T viewed from the center of gravity of the image pattern P is adjusted to be 90 degrees with the vectors Va and Vb. This situation is shown in FIG. Here, the target T is a position on the CRT phosphor screen that is a target for matching the barycentric points of the image pattern P, and the center of the CRT phosphor screen is usually the target T.
[0037]
If the direction of the target T makes an angle of 90 degrees with the directions of the vectors Va and Vb, the direction of the resultant force of the vectors Va and Vb is the same when the centering magnets Ma and Mb are rotated in the opposite direction by the same angle. The size does not change in accordance with the direction of the target T, and its size changes according to the rotation angle of the centering magnets Ma and Mb.
[0038]
That is, the center of gravity of the image pattern P passes through the target T if the centering magnets Ma and Mb are rotated in the opposite direction by the same angle. Therefore, the rotation angles of the centering magnets Ma and Mb can be adjusted so that the center of gravity of the image pattern P matches the target T. This state is shown in FIG.
[0039]
In this way, if the barycentric point of the image pattern P is made to coincide with the target T, the image pattern to be output is adjusted by adjusting the V (vertical size), H (horizontal size), and K (keystone) volumes. P is set to a normal size, and the deviation from the actual CRT screen frame is inspected. This situation is shown in FIG. This amount of deviation varies depending on individual differences in CRT.
[0040]
If the deviation is within the allowable range, the adjustment is finished. If the deviation is outside the allowable range, the V, H, and K volumes are adjusted again to increase the size of the image pattern P. The centering magnets Ma and Mb shown in (d) to (g) of FIG. 1 are repeatedly adjusted.
[0041]
FIG. 4 shows a schematic diagram of a system for carrying out such a method for adjusting the CRT image output position by the centering magnet. In this system, a CRT screen is photographed by a television camera 10, and based on the photographed image information, a motor is driven and centering magnets Ma and Mb are rotated to automatically adjust an image output position.
[0042]
The pattern input unit 13 generates a signal for displaying a predetermined video pattern on the CRT and outputs the signal to the CRT. The image processing unit 11 performs predetermined analysis processing on the information on the CRT screen photographed by the television camera 10 to obtain the center of gravity or diagonal intersection of the video pattern and the position of the center of the CRT screen serving as the target T. The controller 12 controls the motor driving unit 14 based on the output of the image processing unit 11 to rotate the centering magnets Ma and Mb by a predetermined direction and angle. By using such a system, the image output position adjusting method according to the present invention can be automatically performed.
[0043]
A configuration example of a control mechanism for a centering magnet driven by a motor is shown in FIGS. This control mechanism is used in the system shown in FIG.
[0044]
FIG. 5 shows a state in which the CRT is set in the adjusting device. The CRT having the deflection yoke Y is set with the display screen D facing upward, and the TV camera 10 faces above the CRT. It is attached. The centering magnet Ma rotatably attached to the deflection yoke Y has a gear-like outer peripheral portion and is connected to adjustment gears Ga1 and Ga2 that transmit the rotation of the motor Ma. Although not shown in the drawing, the centering magnet Mb is also connected to other adjustment gears Gb1 and Gb2.
[0045]
In this figure, a flat cathode ray tube is shown as a CRT whose image output position is adjusted. However, even in the case of a normal cathode ray tube which is not flat type, the television camera 10 is opposed to the CRT display screen D, that is, in the horizontal direction. Of course, it can be adjusted in the same way by mounting.
[0046]
6 is a cross-sectional view showing a cross section taken along the line AA of FIG. In the CRT, the screen display unit D is supported by the support unit Sd of the adjustment table T, and is fixed by being sandwiched between the placing table St and the movable presser unit Sc.
[0047]
In this state, the rotation of the drive shaft of the motor Ma provided on the adjustment table T is transmitted to the adjustment gear Ga via the timing belt TBa and transmitted to the centering magnet Ma meshed with the adjustment gear Ga. Is done. Here, the adjustment gear Ga corresponds to the adjustment gears Ga1 and Ga2 in FIG.
[0048]
Similarly, the rotation of the drive shaft of the motor Mb provided in the movable presser portion Sc is transmitted to the adjustment gear Gb via the timing belt TBb, and is further centered with the adjustment gear Gb. Is transmitted to Ma.
[0049]
FIG. 7 is a cross-sectional view showing a cross section taken along line BB of FIG. The centering magnets Ma and Mb are both in mesh with two adjustment gears. That is, the centering magnet Ma meshes with the adjustment gears Ga1 and Ga2 and the rotation of the motor Ma is transmitted, while the centering magnet Mb meshes with the adjustment gears Gb1 and Gb2 and the rotation of the motor Mb is transmitted. Is done. Here, the adjustment gears Gb1 and Gb2 correspond to the adjustment gear Gb in FIG.
[0050]
In this way, since the centering magnet is driven via two or more adjustment gears, the rotation of the motor can be transmitted reliably and with high accuracy. After adjusting the image output position, the movable presser portion Sc Open and take out the CRT.
【The invention's effect】
[0051]
The automatic adjustment apparatus for the CRT image position described in claim 1 and the CRT image position adjustment method described in claim 5 are configured such that the direction of a vector acting on the image pattern on the CRT screen matches the direction of the target. Then, the output position of the image pattern is matched with the target by adjusting the size of the vector.
[0052]
That is, since the image output position is adjusted with reference to the target position, the position of the image pattern to be output can be accurately matched with the target. Therefore, it is possible to perform the adjustment work even if it is not a skilled worker, and it is possible to provide an automatic adjustment device that performs automatic adjustment with high accuracy.
[0053]
The automatic adjustment device for the CRT image position described in claim 2 and the CRT image position adjustment method described in claim 6 determine the diagonal intersection or the center of gravity position of the image pattern displayed on the CRT screen, Since this is the position of the video pattern, the accuracy when matching with the target can be improved. Further, when image processing is performed by photographing with a television camera, processing of image data becomes easy.
[0054]
The automatic adjustment device for the CRT image position described in claim 3 and the CRT image position adjustment method described in claim 7 make a constant magnetic force relationship between the centering magnets using the trajectory of the image pattern. . In other words, by simply rotating the centering magnet and observing the trajectory of the video pattern, the polarities of both the centering magnets can be matched, so that the polarity can be easily adjusted at the start of adjustment.
[0055]
The automatic adjustment apparatus for the CRT output position described in claim 4 and the CRT output position adjustment method described in claim 8 adjust the output position in a state where the image pattern is minimized. Prevents out-of-frame on the CRT screen and makes it easy to recognize the locus of the image pattern. Therefore, it is possible to easily adjust the image output position.
[0056]
According to the ninth aspect of the present invention, the adjustment position of the CRT output position is such that the adjustment gear is engaged with the outer periphery of the centering magnet when the output position is adjusted, and the rotation of the motor is transmitted via the adjustment gear. In order to adjust the image output position, the centering magnet can be rotated by driving the motor. Accordingly, it is possible to automatically adjust the image output position.
[Brief description of the drawings]
FIG. 1 is a diagram showing an example of a method for adjusting a CRT image output position according to the present invention.
FIG. 2 is a diagram illustrating an example of a method for adjusting the CRT image output position according to the present invention, following FIG. 1;
FIG. 3 is a diagram illustrating an example of a method for adjusting a CRT image output position according to the present invention, following FIG. 2;
FIG. 4 is a schematic diagram of an example of a system for carrying out the CRT image position adjustment method according to the present invention.
FIG. 5 is a diagram showing a configuration example of a control mechanism for a centering magnet driven by a motor.
6 is a cross-sectional view showing a cross section taken along line AA of FIG.
7 is a cross-sectional view showing a cross section taken along the line BB of FIG. 5;
FIG. 8 is a view showing a CRT provided with a centering magnet.
FIG. 9 is a diagram schematically showing the movement of an electron beam in a flat cathode ray tube.
FIG. 10 is a diagram three-dimensionally showing how a force vector acts on an image on a CRT screen by a centering magnet.
FIG. 11 is a plan view showing a state in which a force vector acts on an image on a CRT screen by a centering magnet.
[Explanation of symbols]
Ma, Mb ... centering magnet T ... adjusting table 10 ... TV camera 11 ... image processing unit 12 ... controller 13 ... pattern input unit 14 ... motor drive unit Va, Vb .. Vector P ... Image pattern T ... Target Ga1, Ga2, Gb1, Gb2 ... Adjustment gear

Claims (9)

An adjustment base for mounting and fixing a CRT having at least two centering magnets;
A pattern input unit for generating a video signal for displaying a predetermined video pattern on the CRT;
A motor for rotating the centering magnet of the CRT, and a motor drive unit for driving the motor;
A TV camera provided opposite to the CRT phosphor screen and capturing a CRT screen;
Based on video information output from the TV camera, an image processing unit that obtains at least the output position of the video pattern;
A controller that outputs a control signal to the pattern input unit and the motor drive unit based on the output of the image processing unit;
In a CRT output position automatic adjustment device that adjusts an output position by rotating a centering magnet based on output information on a CRT screen.
By rotating each centering magnet in sequence and making the poles of both centering magnets coincide with each other, the force vector of the Lorentz force acting on the electron beam by these magnets is made the same direction. Rotate 90 degrees in the opposite direction, and make the polarities of the centering magnets in the opposite directions, thereby making the vectors opposite to each other,
Next, by rotating each centering magnet in the same direction and by the same angle, the direction of the resultant force of both vectors is made to coincide with the direction of the target on the CRT screen, and the centering magnets are made in opposite directions to each other. An apparatus for automatically adjusting a CRT output position, wherein the output position of an image pattern is matched with a target by adjusting the magnitude of the resultant force vector by rotating the same angle. In the automatic adjustment apparatus of the CRT image output position according to the present invention as set forth in claim 1,
CRT output position automatic adjustment device characterized in that diagonal intersection or centroid of image pattern coincides with target position In the automatic adjustment apparatus of the CRT image output position according to the present invention as set forth in claim 1 or 2,
Before rotating both magnets so that the Lorentz force by each centering magnet is in the opposite direction,
Each centering magnet is rotated in turn, and when the trajectory of the image pattern due to each rotation reaches the apex position, the rotation of each centering magnet is stopped, so that the direction of the force vector due to each Lorentz force is between each centering magnet. A device for automatically adjusting the CRT image output position, characterized in that a magnetic force relationship is established. In the automatic adjustment apparatus for the CRT image output position according to the present invention as set forth in claim 3,
An apparatus for automatically adjusting a CRT image output position, wherein the image pattern trajectory is recognized in a state where the size of the image pattern is minimized. In a method for adjusting the CRT image output position, which comprises at least two centering magnets and adjusts the image output position on the phosphor screen by rotating these centering magnets.
By rotating each centering magnet in sequence and making the poles of both centering magnets coincide with each other, the force vector of the Lorentz force acting on the electron beam by these magnets is made the same direction. Conversely direction rotated 90 degrees, and the two vectors in the opposite directions by the polarity of each of the centering magnet and the opposite direction,
Next, by rotating each centering magnet in the same direction and by the same angle, the direction of the resultant force of both vectors coincides with the direction of the target on the CRT screen,
Further, the CRT output position is characterized in that the output position of the image pattern is made to coincide with the target by adjusting the magnitude of the resultant force vector by rotating both centering magnets by the same angle in opposite directions. Adjustment method. In the adjustment method of the CRT image output position according to claim 5 ,
A method for adjusting a CRT output position, characterized in that a diagonal intersection or a center of gravity of the image pattern coincides with a target position. In the method for adjusting the CRT image output position according to claim 5 or 6,
Before rotating both magnets so that the Lorentz force by each centering magnet is in the opposite direction, each centering magnet is rotated sequentially, and when the trajectory of the image pattern due to each rotation is at the apex position, A method for adjusting a CRT image output position, characterized in that a magnetic force relationship in which the direction of a force vector by each Lorentz force coincides between each centering magnet by stopping each rotation . The method for adjusting the CRT image output position according to claim 7,
A method for adjusting a CRT image output position, wherein a locus of an image pattern is recognized in a state where the size of the image pattern is minimized. In the adjustment method of the CRT image output position according to any one of claims 5 to 8,
The outer periphery of the centering magnet is formed in a gear shape,
When adjusting the image output position, mesh the adjustment gear with the outer periphery of the centering magnet,
A method for adjusting a CRT output position, wherein the output position is adjusted by transmitting the rotation of a motor through the adjusting gear.

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