JP2943169B2 - Convergence measurement device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a convergence measuring device for measuring a convergence state of a color CRT of a television receiver.

[Summary of the Invention] The present invention generates a color signal by generating a video signal representing a plurality of bright line patterns generated in a predetermined cycle, the plurality of bright lines being separated from each other by a predetermined bright line interval δ. A pattern generator for outputting to a CRT, an optical sensor having a directional sensitivity characteristic of a single peak characteristic arranged at a position facing the tube surface of the color CRT, and a basic waveform for each primary color are created from the detection output of the optical sensor. A misconvergence amount calculating means for calculating a misconvergence amount from a phase difference between the basic waveforms, wherein the bright line pattern is located at a plurality of bright line shift positions obtained by dividing the bright line interval δ by N (N is an integer of 2 or more). In the case of shifting the bright line shift position, at least one bright line shift position adjacent to the predetermined bright line shift position in one direction from the predetermined bright line shift position during one cycle of shifting to all of the plurality of bright line shift positions. And the number of shifts from the predetermined bright line shift position to the number of shifts from the predetermined bright line shift position to the adjacent bright line shift position in the other direction. The shift control is performed to shift to a bright line shift position separated by at least twice the distance between the bright line shift positions.

By shifting the bright line pattern transferred to the surface of the color CRT in this way, the phase shift of the reference waveform caused by the effects of afterglow can be suppressed as much as possible, enabling more accurate measurement. It is.

[Prior Art] The present applicant has previously proposed a convergence measuring device of the phase detection type (see Japanese Patent Application No. 63-310670). This convergence measuring device uses a color CRT
A pattern generator for projecting a plurality of bright lines positioned at regular intervals on the tube surface of the color CRT and shifting the bright lines by 1 / N (N is an integer of 2 or more) of the interval in the vertical direction;
An optical sensor having a directional sensitivity characteristic of a single peak characteristic and a calculating means for calculating a misconvergence amount from a detection output of this optical sensor for each primary color are provided.

For example, in the case where N is N = 4 and the bright line shift position (the position where the bright line is shifted and projected) is four patterns of A, B, C and D positions as shown in FIG. , A, the three primary colors R, G, and B are projected in the order, then the position B is projected again in the order of the three primary colors, R, G, and B, and this is repeated in order to produce a bright line.

The light sensor detects the projected bright line light, and the calculating means creates an envelope curve (basic waveform) for each primary color from the detection output of each primary color of the optical sensor, and a peak value of the envelope curve (basic waveform). The misconvergence amount is calculated by comparing the positions of the peak values for each primary color and detecting the phase difference between the basic waveforms.

[Problems to be Solved by the Invention] In any of the bright line shift positions A, B, C, and D, the primary colors G and B are the same as the bright line shift position of the primary color R at the same bright line shift position. Because it is reflected in the position, it is not affected by afterglow.

However, since the primary color R is projected at a bright line shift position different from the bright line shift position of the primary color B after the primary color B projected last time, the primary color R is affected by the afterglow of the pattern of the primary color B projected last time.

Due to this afterglow, when the light of the primary color R is detected, the light sensor also detects the afterglow of the previous primary color B together, and the light sensor has an R emission line at the position shown by the broken line in FIG. Since a detection output is obtained and the basic waveform of R is shifted in phase due to the effect of afterglow, there is a disadvantage that an accurate misconvergence amount cannot be calculated.

Therefore, an object of the present invention is to provide a convergence measuring device that minimizes a measurement error caused by the influence of afterglow.

[Means for Solving the Problems] A convergence measuring apparatus of the present invention for achieving the above object is as follows: (1) A plurality of bright line patterns generated in a predetermined cycle, each having a predetermined bright line interval δ Generates a video signal representing a bright line pattern consisting of multiple separated bright lines
A pattern generator for outputting to a CRT, and controlling the pattern generator, wherein the bright line interval δ
Is shifted to a plurality of bright line shift positions obtained by dividing the bright line pattern by N (where N is an integer of 2 or more). Control means for performing shift control in which the number of times of shifting from the bright line shift position to the adjacent bright line shift position in one direction and the number of times of shifting from the predetermined bright line shift position to the adjacent bright line shift position in the other direction are substantially the same; An optical sensor having a directional sensitivity characteristic of a single peak characteristic disposed at a position facing the tube surface of the color CRT, and generating a basic waveform for each primary color from a detection output of the optical sensor; And a misconvergence amount calculating means for calculating a misconvergence amount from the phase difference. (2) The shift control in the control means includes the steps of: It is characterized in that it includes a shift control to shift the emission line shift position spaced more than twice the distance between the emission line shift position adjacent to the line shift position and the position.

[Operation] 1 for shifting to all of the plurality of bright line shift positions
During the cycle, at least the circuit for shifting from the predetermined bright line shift position to the adjacent bright line shift position in one direction and the number of times of shifting from the predetermined bright line shift position to the adjacent bright line shift position in the other direction are substantially the same. The bright line pattern is shift-controlled so as to be as follows.

Then, the phase shift of the basic waveform due to the effect of the afterglow, which occurs when shifting from the predetermined bright line shift position to the bright line shift position adjacent to the position, is totally canceled.

Further, when the bright line pattern is shifted from a predetermined bright line shift position to a bright line shift position at least twice the distance between the bright line shift position and a bright line shift position adjacent to the bright line shift position, a basic waveform due to afterglow Does not occur.

For this reason, the phase shift of the basic waveform due to the effect of afterglow is prevented as much as possible, and a highly accurate measurement result is obtained.

Embodiment An embodiment of the present invention will be described below with reference to the drawings. Second
The figure shows the measurement state of the convergence measuring device A. In FIG. 2, a color CRT (color cathode ray tube) 1 to be measured is built in a television receiver B, and a tube surface 2 of the color CRT 1 is exposed to the front.

The signal cable 3 of the convergence measuring device A is connected to a video signal input terminal of the television receiver B, and a color CR is output by the video signal output from the convergence measuring device A.
An image is projected on the screen 2 of T1. The convergence measuring device A has an optical sensor 4 connected by a cable,
The optical sensor 4 is disposed at a contact position of the tube surface 2 so as to face the tube surface 2.

FIG. 3 is a cross-sectional view showing a positional relationship between the tube surface 2 and the optical sensor 4. In FIG. 3, the tube surface 2 has a fluorescent portion 2b disposed on an inner surface of a panel glass 2a.
It emits light when the electron beam is irradiated on 2b. The optical sensor 4 is provided with a microswitch SW. When the optical sensor 4 is brought into contact with the tube surface 2, the microswitch SW is turned on. The measurement is started by the ON signal of the microswitch SW and the
The flowchart shown in FIG. 10 is executed.

FIG. 4 shows a directional sensitivity characteristic diagram of the optical sensor 4. In FIG. 4, the horizontal axis indicates the incident angle (degree) of light incident on the optical sensor 4 from the tube surface 2 of the color CRT 1, and the vertical axis indicates the intensity (incident angle) of the incident light on the optical sensor 4 at each incident angle. Are relative light intensities when the light intensity is 100% when the light intensity is 0 °. The directional sensitivity characteristic of the optical sensor 4 is maximum when the incident angle is 0 °, the light intensity decreases as the absolute value of the incident angle increases, and the absolute value of the incident angle becomes approximately 20 °.
It exhibits a so-called single peak characteristic of 0% at about 呈.

FIG. 1 shows a circuit block diagram of the convergence measuring device A. In FIG. 1, the detection output (light intensity data) of the optical sensor 4 is transmitted via an amplifier 5 to an A / D converter 6.
And digitized by the A / D converter 6. The digitized light intensity data is written to the measurement data memory 7 based on a write signal of the CPU 8.

The CPU 8 has an operation memory 9 in addition to the measurement data memory 7.
In addition, the read / write of the program memory 10 is controlled. The calculation memory 9 stores calculation data necessary for performing calculation processing on various data. The program memory 10 stores data for executing a measurement program, a modulation degree calculation program, a white area change program, an emission line interval automatic correction program, a misconvergence amount calculation program, and a display program. The contents of each program will be described together with the following operations.

The CPU 8 has a modulation factor calculating means driven according to a modulation factor calculating program and a misconvergence amount calculating device driven according to a measuring program. The modulation degree calculating means calculates the maximum value MAX and the minimum value M of the light intensity data of the primary colors measured first.
List IN and (MAX-MIN) / (MAX + MIN) = F
Is calculated to calculate the modulation factor F.

If the value of the degree of modulation is in the range of 0.2 to 0.6, it is determined to be appropriate, and if it is outside this range, it is determined to be inappropriate. If determined to be inappropriate, the modulation factor data is used to calculate the bright line interval calculation unit 11.
Send to If the value of the degree of modulation is almost zero, a white area change command is sent to the white area setting unit 12.

In this embodiment, the modulation degree calculating means determines the modulation degree from the difference between the maximum value and the minimum value of the light intensity data. However, the state of the envelope curve of the light intensity data (for example, the difference between the maximum value and the minimum value of the curve, (Inclination angle).

The misconvergence amount calculating means interpolates the discrete light intensity data (shown in FIG. 5) read from the measurement data memory to obtain an envelope curve (basic waveform) that changes finely as shown by a broken line in FIG. Detecting the point (position) at which the peak value of the envelope curve (basic waveform) for each primary color is obtained, for example, the red and blue light intensity data for the point (position) at which the peak value of the green light intensity data is obtained The difference from the time (position) at which the peak value is obtained, that is, the amount of misconvergence is calculated.

Further, the CPU 8 calculates the bright line interval calculation unit 11,
The white area setting unit 12 and the display unit 13 are driven and controlled. The bright line interval calculation unit 11 outputs bright line interval data that determines the interval δ between bright lines projected on the display screen 2. If the value of the modulation factor output from the CPU 8 is a value other than 0.2 to 0.6, the value of the modulation factor is calculated. Outputs the bright line interval data according to the value.

The white area setting unit 12 designates a white area of the screen. In this embodiment, one of the right half and the left half of the screen 2 is set as a white area. When a white area change command is sent from the CPU 8, white area data is output in which an area opposite to the previous area is set as a white area. The display unit 13 displays the amount of misconvergence and the like, and displays the value of the modulation factor for manually correcting the interval between the emission lines when the automatic line interval correction program is not provided. Further, the CPU 8 has a keyboard 14
Is input.

By inputting data from the keyboard unit 14, data in the arithmetic memory 9, the program memory 10, and the like can be updated. When the distance between the bright lines is manually corrected, the data is input from the keyboard unit 14 and corrected.

Bright line interval data and white area data are input to the pattern generator 15 via the CPU 8. As shown in FIG. 7, the pattern generator 15 whitens the area specified by the white area data and arranges vertical or horizontal emission lines of each primary color at regular intervals δ in other areas. A video signal of a pattern to be generated is generated.

Then, the position of each bright line is set in the vertical direction by the distance δ.
N projected at a position shifted by 1 / N (N is an integer of 2 or more)
Number of patterns. In this embodiment, N is 4, and in each of these patterns, the bright lines are arranged at the positions indicated by the solid line, the one-dot chain line, the two-dot chain line, and the three-dot chain line in FIG.

The order of the patterns output to the color CRT 1 is determined so as to minimize the effect of afterglow. As means for reducing the effect of afterglow, there are the following means: (1) Shift to all of the plurality of bright line shift positions. During the cycle, at least, the number of times to shift from a predetermined bright line shift position to an adjacent bright line shift position in one direction,
A method of performing a shift control in which the number of times of shifting from a predetermined bright line shift position to a bright line shift position adjacent in another direction is substantially the same; and (2) a bright line shift position and a position adjacent to the bright line shift position from the predetermined bright line shift position. There is a method of shifting to a bright line shift position separated by at least twice the distance between the bright line shift positions.

That is, as shown in FIG. 9 (a), assuming that the four bright line shift positions are A, B, C, and D, the order of the patterns output to the color CRT1 is A → B → D → C. Primary color in position
Bright lines are generated in the order of R, G, B.

The detection output of the optical sensor 4 is based on the position of the bright line (A → B → C
Sorting in the order of D) results in discrete light intensity data exhibiting a characteristic that changes in an alternating manner, as shown in FIG.

Therefore, the optical sensor 4 may be located at an arbitrary position with respect to the tube surface 2 of the color CRT 1, and the measurement period may be four data in principle. Hereinafter, the operation of the above configuration will be described with reference to the flowchart of FIG.

When the optical sensor 4 is brought into a contact state at an arbitrary position on the tube surface 2 of the color CRT 1, the micro switch SW is turned on. The CPU 8 first executes a modulation degree calculation program in response to the ON signal of the micro switch SW. That is, the bright line interval data of the bright line interval calculating unit 11 and the white area data of the white area setting unit 12 are sent to the pattern generator 15 by the control signal of the CPU 8.

The pattern generator 15 creates an image signal based on this data, and an image of a pattern in which a green bright line is arranged in addition to the white area as shown in FIG. Then, the pattern of the bright line is switched in a predetermined order for each frame, for example, and the light intensity data (see FIG. 5) of each pattern is taken into the measurement data memory 7.

When the green light intensity data is captured, the modulation degree of the light intensity data is calculated by the modulation degree calculating means. If the value of the modulation degree is almost zero, the white area change program interrupts and the white area is changed. And the value of the modulation depth is
If the value is outside the range of 0.2 to 0.6, the bright line interval automatic correction program interrupts and the bright line interval δ is corrected.

After the white area change program and the bright line interval automatic correction program are finished, if the value of the modulation factor is in the range of 0.2 to 0.6, the program shifts to the measurement program without interruption. In this measurement program, green, red and blue bright lines are transferred to the tube surface 2 and light intensity data as shown in FIG. 5 is stored in the measurement data memory 7 for each of green, red and blue.

Next, a misconvergence amount calculation program is executed, an envelope curve (basic waveform) is obtained for each color by the misconvergence amount calculation means, and a time point (position) at which a peak value of green light intensity data is obtained from the envelope curve. , The difference from the time (position) at which the peak values of the red and blue light intensity data are obtained, that is, the amount of misconvergence is calculated.

Finally, the display program is executed, and the display unit 13 displays the misconvergence amount.

In the above measurement program, the order of the pattern of the bright lines is as shown in FIG. 9 (a). At the position _A , the bright lines are projected in the order of red (R _A ) → green (G _A ) → blue (B _A ). . At this time, green (G _A ) and blue (B _A ) are reflected at the same bright line position as red (R _A ), so there is no influence of afterglow.

Then red in position B (R _B) → green (G _B) → bright line in the order of blue _(B B) is projected. At this time, the red (R _B ) emission line at the B position is affected by the afterglow of the blue (B _A ) emission line at the A position, and the phase of the basic waveform shifts in the plus direction as indicated by the broken line at the B position. Act like so.

Next, at the position _D , bright lines are projected in the order of red (R _D ) → green (G _D ) → blue (B _D ). In this case, the D position is a position far from the B position, that is, a position separated by at least twice the distance between the adjacent bright line shift positions, so that the red (R _D ) bright line at the _D position is blue (B) at the B position. _B ) It is not affected by the afterglow of the emission line.

Next, at the position _C , a bright line is projected in the order of red (R _C ) → green (G _C ) → blue (B _C ). At this time, the red (R _C ) emission line at the C position is affected by the afterglow of the blue (B _D ) emission line at the D position, and the phase of the basic waveform shifts in the negative direction as shown by the broken line at the C position. Act like so.

Next, again at the position _A , a bright line is projected in the order of red (R _A ) → green (G _A ) → blue (B _A ). In this case the position A, the distal position from the C position, i.e. a position spaced more than twice the distance between adjacent bright lines shift position to each other, the A position red (R _A)
Is not affected by the afterglow of the blue (B _C ) emission line at the C position.

At the positions B and C, there is a phase shift of the basic waveform shown by the dashed line.However, since these phase shift directions are opposite to each other, the total is canceled, and a basic waveform hardly affected by afterglow can be obtained. it can. Accordingly, a basic waveform of each primary color which is not affected by afterglow is obtained, and a highly accurate measurement result can be obtained.

In this embodiment, the case where N = 4, that is, four bright line patterns has been described. However, the present invention can be applied to the case where N is other than four. For example, when N = 5, the bright line pattern is shifted at bright line shift positions A, B, C, D and E as shown in FIG. 9 (b).

That is, after the emission line is projected in the order of red (R _A ) → green (G _A ) → blue (B _A ) at the position A, red (R _C ) → green (G _C ) →
After projecting emission lines in the order of blue (B _C ), red (R _E ) at position _E
→ After reflects the bright line in the order of green (G _E) → blue (B _E), red in the B position (R _B) → green (G _B) → After reflects the bright line in the order of blue _(B B), D position in project a bright line in the order of red (R _D) → green (G _D) → blue (B _D).

In this case, the positions to be shifted are all positions separated by at least twice the distance between the adjacent bright line shift positions, so that the afterglow is not affected at any of the bright line shift positions.

When N = 6, for example, the bright line pattern is shifted at bright line shift positions A, B, C, D, E and F as shown in FIG. 9 (c).

That is, after the emission line is projected in the order of red (R _A ) → green (G _A ) → blue (B _A ) at the position A, red (R _C ) → green (G _C ) →
After projecting bright lines in the order of blue (B _C ), red (R _F ) at F position
→ After reflects the bright line in the order of green (G _F) → blue (B _F), after which reflects the bright line in the order of red (R _D) → green (G _D) → blue (B _D) in the D position, B position in after reflects the bright line in the order of red (R _B) → green (G _B) → blue _(B B), a bright line in the order of red (R _E) → green (G _E) → blue (B _E) in the E position After projecting, red at position _B (R _B ) →
Project a bright line in the order of green (G _B) → blue _(B B).

In this case, the positions to be shifted are all positions separated by at least twice the distance between the adjacent bright line shift positions, so that the afterglow is not affected at any of the bright line shift positions.

[Effects of the Invention] As described above, according to the present invention, a bright line pattern of a plurality of colors generated at a predetermined cycle and comprising a plurality of bright lines separated from each other by a predetermined bright line interval δ is exhibited. Generates video signal and color CRT
And a pattern generator for controlling the pattern generator to shift the bright line pattern to a plurality of bright line shift positions obtained by dividing the bright line interval δ by N (N is an integer of 2 or more). In one cycle of shifting to all of the bright line shift positions, at least the number of shifts from the predetermined bright line shift position to the bright line shift position adjacent in one direction and the bright line shift from the predetermined bright line shift position to the other direction Control means for performing shift control in which the number of shifts to the position is substantially the same; an optical sensor arranged at a position facing the tube surface of the color CRT and having a directional sensitivity characteristic of a single peak characteristic; A basic waveform for each primary color from the output, and a misconvergence amount calculating means for calculating a misconvergence amount from a phase difference between the basic waveforms; Further, the shift control in the control means includes a shift control for shifting from a predetermined bright line shift position to a bright line shift position separated by at least twice the distance between the bright line shift position and a bright line shift position adjacent to the bright line shift position. With such a configuration, the following excellent effects can be obtained.

(1) According to the first aspect of the invention, the phase shift of the basic waveform due to the effect of afterglow, which occurs when shifting from a predetermined bright line shift position to a bright line shift position adjacent to the predetermined position, is totally canceled. Is done. This eliminates the effects of afterglow,
Highly accurate measurement can be performed.

(2) According to the second aspect of the invention, there is no phase shift of the basic waveform due to afterglow. For this reason, the phase shift of the basic waveform due to the effect of afterglow is prevented as much as possible, and a highly accurate measurement result is obtained.

[Brief description of the drawings]

1 to 10 show an embodiment of the present invention, FIG. 1 is a circuit block diagram of a convergence measuring device, FIG. 2 is a perspective view showing a measuring state, and FIG. 3 is a position of a tube surface and an optical sensor. FIG. 4 is a cross-sectional view showing the relationship, FIG.
FIG. 5 is a diagram showing light intensity data, FIG. 6 is a diagram showing light intensity data having an appropriate modulation factor, FIG. 7 is a front view of a television receiver, and FIG. 8 is a diagram showing arrangement of bright lines. , FIG. 9 is a diagram showing the order of the bright line patterns, FIG. 10 is a flowchart, and FIG. 11 is a diagram showing the order of the conventional bright line patterns. A: Convergence measuring device, 1: Color CRT, 2
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Claims (2)

(57) [Claims] 1. A video signal representing a plurality of bright line patterns generated in a predetermined cycle and comprising a plurality of bright lines separated from each other by a predetermined bright line interval δ is generated and output to a color CRT. A pattern generator for controlling the pattern generator to shift the bright line pattern to a plurality of bright line shift positions obtained by dividing the bright line interval δ by N (N is an integer of 2 or more); In one cycle of shifting to all positions, at least the number of times of shifting from a predetermined bright line shift position to an adjacent bright line shift position in one direction, and shifting from the predetermined bright line shift position to an adjacent bright line shift position in another direction A control means for performing a shift control in which the number of times of performing is substantially the same; And a misconvergence amount calculating means for calculating a misconvergence amount from a phase difference between the respective basic waveforms based on the detection output of the optical sensor. apparatus. 2. The shift control according to claim 1, wherein the shift control is performed to shift from a predetermined bright line shift position to a bright line shift position separated by at least twice the distance between the bright line shift position and a bright line shift position adjacent to the bright line shift position. The convergence measurement device according to claim 1, wherein the convergence measurement device includes: