JPS6262692A - Measuring instrument for deviation of beam position - Google Patents

Abstract

PURPOSE:To measure a beam position with high accuracy by generating an inclined pattern on a picture and photodetecting this inclined pattern by a sensor disposed at a prescribed position. CONSTITUTION:A television receiver 1 to be adjusted is mounted on a mounting base 2 in which a computer 3 is incorporated and adjusted. When adjusting a deflection and a convergence, a pickup 4 is attached by an L-shaped fixture 5 to a prescribed position to a fluorescent surface of a cathode ray tube. To the television receiver 1 to be adjusted, an inclined pattern of a prescribed luminance is supplied from the computer 3 correspondingly to respective sensors of the pickup 4. A projected pattern is respectively photodetected by photodiodes S(1, 1)-S(7, 9) corresponding to respective patterns and outputs of the photodiodes S(1, 1)-S(7, 9) are successively supplied to a computer 6. The position information of an electronic beam is calculated from the outputs of these photodiodes S(1, 1)-S(7, 9) by the computer 6.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a beam position deviation measuring device suitable for use in adjusting deflection and convergence of a television receiver.

[Summary of the Invention] The present invention provides a beam position deviation measuring device suitable for use in adjusting the deflection and convergence of a television receiver, in which a plurality of sensors are placed facing each other at predetermined positions on a tube surface,
By creating a tilt pattern for each sensor position and detecting the beam positional deviation from the output of each sensor, it is possible to measure the beam positional deviation with high accuracy.

(Prior Art) In order to adjust the deflection and convergence of a television receiver on a production line, conventionally, a predetermined dot pattern is projected on the screen of the television receiver, this dot pattern is imaged by a color camera, and the dot pattern is imaged by a color camera. The output is stored in memory, and red, green,
The positional information of the electron beam was obtained by finding the center of each blue dot, and the process was based on this positional information.

[Problem that the invention seeks to solve]

However, complicated calculations are required to obtain the position information of each of the red, green, and blue beams from the image pickup output of the color camera stored in the memory in this manner. Also, when measuring using a color camera like this,
Since measurement accuracy is determined by the color camera's sampling frequency, there are limits to the measurement accuracy. Historically, many color cameras are required to simultaneously scan and determine many measurement points, and high-speed Requires precision mechanics. Therefore, there is a problem that the device becomes large and expensive.

Therefore, an object of the present invention is to provide a beam position deviation measuring device that can measure beam position with high precision and in a short time without using a color camera.

Another object of the present invention is to provide a beam position measuring device that is small and inexpensive.

[Means for solving problems]

In this invention, a plurality of sensors are arranged facing each other at predetermined positions on the tube surface of a color cathode ray tube, and a tilt pattern is generated at each sensor position, so that the beam of the color cathode ray tube from a reference position at each sensor position is This is a beam position deviation measurement device designed to detect position deviation.

[Effect]

On the television receiver to be adjusted, a predetermined gradient pattern of luminance changes is displayed corresponding to each sensor placed at a predetermined position on the screen. A sensor placed at a predetermined position on the tube surface receives light from the tilted pattern projected on the television receiver. The beam position shift is calculated from the detection output of this sensor.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows the overall configuration of an embodiment of the present invention. As shown in FIG. 1, a television receiver 1 to be adjusted is placed on an R stand 2 in which a computer 3 is installed. Deflection and Convergence 8
When adjusting the circumference, the pickup 4 is attached to a predetermined position facing the fluorescent surface of the cathode ray tube of the television receiver 1 using an L-shaped fixture 5, as shown in FIG.

As shown in FIG. 3, the pickup 4 includes a predetermined number of optical sensors, for example 63 photodiodes S (1,1
) to S (7, 9) are arranged in a two-dimensional array. The outputs of these photodiodes S (1,1) to S (7,9) are as shown in FIG.
, 9), integrator I (1°1) ~ I ('l, 9
) are supplied respectively. Integrator 1 (1, 1,) ~ I (
7,9) output is analog switch 5W(1,1)~S
The signals are sequentially switched by W (7, 9) and supplied to the A/D converter 11. By the A/D converter 11,
For example, the output of sensors S(1,1) to S(ma,9) is 1
Digitized with 2 bits. The output of this A/D converter 11 is outputted via the I10 port 12 and supplied to the computer 3. These amplifiers A(1,1)
~A (7,9>, integrator + (1°1) ~I
(7,9), analog switch SW (1°1) ~S
W (7, 9) and the A/D converter 11 are housed in the circuit section 6 of the pickup 4 in FIG.

A gradient pattern of predetermined brightness is supplied from the computer 3 to the television image a1 to be adjusted, corresponding to each sensor of the pickup 4.

The projected patterns are received by the photodiodes S (1, 1) to S (7, 9) corresponding to the patterns, respectively, and the photodiodes S (1° 1) to S (7,
9) is supplied to the 1119th computer 6.

These photodiodes S (
1,1)~S (7,9) output to electron beam order 1
t(RfiH is calculated.

Note that the photodiodes S (1, 1) to S in the first row
5 after the output of (1,9) is supplied to computer 3
Photodiodes in the row I's (5,1) to S (5
, 9) is supplied to the computer 3, there is some time leeway. Similarly, the second row of photodiodes and 6
There is a time margin for data extraction between the photodiode in the row, and between the photodiode in the third row and the photodiode in the seventh row. Therefore, each of the photodiodes S (1,1) to S (1,9) in the first row and the photodiode S (5°1) in the fifth row in the same column
) to S(5,9) are connected to each other, and the photodiodes S(2,1) to S(2,9) in the second row and the photodiodes S(6,1) in the sixth row in the same column are connected to each other. )~S
(6,9) are connected to each other, and each of the photodiodes S(3,1) to S(3°9) in the third row and 7 in the same column are connected to each other.
Photodiodes S (7, 1) to S (7, 9) in the row
) may be connected. With this configuration, amplifiers A(1,1) to A(7,9), integrator I
(1°1) to I (7,9) and the number of analog switches SW (1°1) to SW (7,9) can be reduced, for example, from 63 to 36, respectively.

In this way, a gradient pattern of a predetermined brightness is projected on the television receiver 1 at each position corresponding to the photodiodes S (1, 1) to S (7, 9), and this projected pattern is transferred to the photodiode S ( 1,1)~S (7,
It will be explained that the position information of the electron beam is calculated by detecting each of the electron beams in step 9).

As shown in FIG. 5, it is assumed that a video signal having a pattern in which the brightness changes linearly with time t is supplied to a television receiver. If the beam of the television receiver is not shifted, a pattern is projected on the television receiver at a beam position P corresponding to time t, as shown in FIG. 6A. Here, if brightness Q is detected at position P0, brightness level Q0 is obtained.

Suppose that the beam of the television receiver is shifted to the right.

Then, the pattern is displayed on the television receiver with the entire pattern shifted to the right, as shown in FIG. 6B. Here, when the brightness Q is detected at the same position NPa as the position where the brightness level was detected in FIG. 6A, the brightness level becomes Q.

Suppose that the beam of the television receiver is shifted to the left.

Then, as shown in FIG. 6C, the entire pattern is displayed on the television receiver with a shift to the left. Here, when the brightness Q is detected at the same position P0 as the position where the brightness level was detected in FIG. 6A, the brightness level becomes Q2.

In this way, if a video signal with a pattern in which the signal level changes linearly with time t is supplied, and the brightness of the pattern projected by this video signal is detected at the same position, the beam will change from this brightness level. You can see the positional shift. If the beam deviates to the right, the brightness level at position Po decreases to Q, as shown in FIG. 6B, and if the beam deviates to the left, the brightness level at position Po decreases to P
. The brightness level at Q2 increases. The change in brightness level at this position P0 is proportional to the positional shift of the beam. The accuracy of the measurement is determined by the rate of change of the brightness level of the pattern.

In the above description, for ease of understanding, it has been explained that if the change in the input level of the video signal is linear, then the k1 degree level Q can also be detected linearly. However, the output level of the photodiode does not change linearly with respect to the input signal level, as shown in FIG. 7A. Therefore, as shown in Figure 7B, the value at which the output of the photodiode changes linearly in response to the position of the electron beam is calculated and stored in memory in advance, and the human signal level is determined based on the output of this memory. I'm trying to change it.

When detecting beam positional deviation, see Figures 8A and 8.
Patterned with the slope pattern shown in Figure B and Figure 8C, respectively,
Five types of patterns are used: pattern l].

The first inclined pattern shown in FIG. 8A is a pattern in which the luminance increases linearly in both the horizontal and vertical directions. The second slope pattern shown in FIG. 8B is a pattern in which the brightness linearly decreases in the horizontal direction and the brightness linearly increases in the vertical direction.

The third inclined pattern shown in FIG. 8C is a pattern in which the brightness linearly increases in the horizontal direction and the brightness linearly decreases in the vertical direction.

When the first inclined pattern is projected, as shown in the eighth doujinshi, a portion of the upper left corner of the pattern becomes the darkest, and a portion of the lower right corner of the pattern becomes the brightest. As shown by the broken line in FIG. 8A, the brightness in the diagonal direction upward to the right becomes equal. The brightness of the pattern gradually becomes brighter as it goes from the upper left to the lower right of the pattern, and in the 8th doujin the solid line M
The brightness indicated by , becomes the median value (Kmax/2).

Note that KmaX is the maximum level of brightness during adjustment, and is the output of the photodiode when an IVP-P video signal is applied, for example.

When the second sloped pattern is projected, a portion of the upper right corner of the pattern is the darkest and a portion of the lower left corner of the pattern is the brightest, as shown in FIG. 8B. As shown by the broken line in FIG. 8B, the brightness in the diagonal direction downward to the right becomes equal. The brightness of the pattern gradually becomes brighter as it goes from the upper right to the lower left of the pattern, and in FIG.
The brightness indicated by is the median value (Kmax/2).

When the third inclined pattern is projected, a portion of the lower left corner of the pattern is the darkest and a portion of the upper right corner of the pattern is the brightest, as shown in FIG. 8C. As shown by the broken line in FIG. 8C, the brightness in the diagonal direction downward to the right becomes equal. The brightness of the pattern gradually becomes brighter from the lower left to the upper right of the screen, and the brightness indicated by the solid line M3 in FIG. 8C is the median value (Kmax/2).

Such a first. Second. By using the third slope pattern, it is possible to determine the beam position shift from the luminance detection output.

For example, in FIG. 9, from the first slope pattern to the brightness,
is obtained, and a brightness of 2 is obtained from the second slope pattern,
Assume that a luminance of 3 is obtained from the third slope pattern. Based on these detection outputs, the positional deviation of the beam from the origin 0, that is, the coordinates of K (x, y) is determined.

That is, as shown in FIG. 8A, in the first inclined pattern, the brightness indicated by the solid line M1 is (Kmax/2), and the brightness on a line parallel to this solid line M1 is equal. In Fig. 9A, if the actual 11M is used as a reference, and the rate of change with respect to the distance in the y direction from the solid line M is Kstep, then + -b+ -Kstep will be obtained at a place away from the solid line M by the distance from the solid line M, and the brightness will be + -b+ -Kstep. It becomes. As a result, the straight line l on the first pattern whose brightness is y=-x+b.

= x + (K+ /Ksmuep)
・ ・ ・ It is obtained as ■.

Similarly, with the second slope pattern, as shown in FIG. 9B, the straight line e2 of the second pattern -H with a brightness of 2 is y=x+b2=x0(K2/Kstep)...・Required as ■.

From equations (1) and (2), the X coordinate of the beam position shift K (x, y) can be determined as shown below.

The rate of change Kstep is the rate of change in brightness. This rate of change Ksl;ep is determined by the luminance pattern L of (Kmax/2-Kstep) and (Kmax/2+Kstep).
It is obtained by using the brightness pattern H of p). In other words, the brightness of pattern L with a brightness of (Kmax / 2-Kstep) is expressed as KL -, (Kmax / 2
+Kstep) If the brightness of pattern H of brightness is □, then K+< -KL =2 ・Kstep ・−−■
becomes. Substituting the rate of change Kstep found by this formula 0 into formula 0, we get:
Coordinates are calculated.

The X coordinate of the beam position shift K (x, y) is the brightness obtained by the first slope pattern, as shown in FIG. 9A, and the third straight line II, as shown in FIG. 9C. From the straight line 13 where the luminance obtained by the slope pattern is 3, the X coordinate can be determined in the same manner as in the case where the X coordinate is determined as in the equation below.

When detecting the positional deviation of the beam, for example, the first tilt pattern is displayed on each screen, and (Kmax / 2-
Kstep) brightness pattern L is projected, and the second
The slope pattern of (K max/ 2 +
Kstep) brightness pattern H is projected, and the third
The slope pattern of the image is displayed. In this way, the measurement is completed with five screens.

The static convergence measurement is performed using the positional deviations (XR, YR), (xc, ,
yc) and (Xw, )'s) are determined, respectively, and are determined by the difference between the red beam R and the blue beam B with respect to the green beam G, which is the center beam.

That is, the static convergence in the horizontal direction is
.

The vertical static convergence is given as yII-yll It is required as.

A measuring method for measuring deflection and convergence using this embodiment will be described with reference to the flowchart shown in FIG.

First, the relationship between the sensor and the brightness is determined (step ①), and based on this characteristic, the above-mentioned first method is determined in which the sensor changes linearly with respect to the beam position for each sensor position. Second. The third slope pattern and (Kmax/2−K
step) pattern and (Kmax / 2 +Ks
tep) pattern I] are created (step ■).

Project these patterns on the screen and adjust the pattern position so that the center of the pattern corresponding to the sensor at the center of the screen coincides (Steps, Steps ■).

Make only the pattern part green to display 5 types of patterns (Step ■), Measure the sensor output of the 5 types of patterns Step (■), Calculate the beam position shift of the green beam G based on the output of this sensor (Step ■). Based on the beam position shift coordinates of the green beam G, the amount of adjustment of the deflection system, such as vertical and horizontal PIN distortion, can be calculated.

Make only the pattern part red to display 5 types of patterns (Step ■), measure the sensor output of the 5 types of patterns (Step ■), calculate the beam position shift of red and color beam R from this sensor output (Step ■).

Set only the pattern part to blue and project the 5 types of patterns (step [phase]), measure the sensor output of the 5 types of patterns (step ()), and use the output of this sensor to determine the beam position shift of the blue beam B. Calculate (step @).

The adjustment amount of the deflection system is calculated based on the beam position shift of the green beam G, and the misconvergence of the red beam R and the blue beam B is calculated with this sensor beam G as the center (step 0).

Note that in the above description, a pattern in which the brightness changes diagonally is used as the brightness gradient pattern for detecting the positional deviation of the beam, but a pattern in which the brightness changes in the horizontal and vertical directions may also be used. .

[Effects of the Invention] According to the present invention, by creating a tilted pattern on the screen and receiving light from this tilted pattern by a sensor placed at a predetermined position, it is possible to measure the beam position with high precision without using a color camera. It can be carried out. Furthermore, since there is no need to use a color camera, the device is small and inexpensive. Furthermore, beam position measurement can be performed in the same way with both the PAL system and the NTSC system.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing the overall configuration of an embodiment of the present invention;
FIG. 2 is a perspective view used to explain the installation of the Pi-7 Quasop in one embodiment of the present invention, and FIG. 3 is a plan view used to explain the arrangement of the sensor in one embodiment of the present invention.
FIG. 4 is a connection diagram of a sensor output section in one embodiment of the present invention, and FIG. 5 is a diagram. 6 and 7 are graphs used to explain one embodiment of this invention, and FIGS. 8 and 9 are lines used to explain when measuring beam position deviation using one embodiment of this invention. 10 are flowcharts used to explain convergence adjustment using an embodiment of the present invention. Explanation of main symbols in the drawings 1: Television receiver i, 3: Computer, 4:
Bisokuasob, S (1, l) ~ S (7°9): Photodiode. Agent Patent Attorney Masaaki Sugiura Tomo # + Parent W (Figure 1, Figure 2)! , 1. Ogudai nogu coon
112-Shin Kiri Fermentation Figure 8A Figure 8B 1st Judgment 3's Fuya Shige 1 Kuhn Figure 8C Nei 3/1 Series Eisukeki 1 and Goober's Examiner Sou R Superintendent Figure 9C

Claims (1)

[Claims] A plurality of sensors are arranged facing each other at predetermined positions on the tube surface of the color cathode ray tube, and a tilt pattern is generated at each position of the sensor to determine the beam position of the color cathode ray tube from the reference position of each of the sensors. A beam position deviation measuring device designed to detect deviations.