JPH02207695A - Convergence measuring instrument - Google Patents

Abstract

PURPOSE:To perform measurement of high precision without extending the measurement time by repeatedly projecting bright line patterns of plural phases, where bright lines of primary colors are gradually shifted, in a certain order to generate an extent of misconvergence for each bright line pattern and summing and averaging the latest extent of misconvergence of each phase. CONSTITUTION:The detection output of an optical sensor 4 is digitized by an A/D converter 6 and is written in a measured data memory 7 based on a write signal of a CPU 8. The CPU 8 is provided with a modulation degree calculating means and a misconvergence extent calculating means which is driven in accordance with a measuring program. The misconvergence extent calculating means converts discrete light intensity data read out from the measured data memory to finely changing light intensity data by interpolation processing to calculate the extent of misconvergence. The misconvergence extent calculating means sums and averages the latest extent of misconvergence of each phase. Thus, measurement of high precision is performed without extending the measurement time.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a convergence measuring device for measuring the convergence state of a color CRT of a television receiver.

[Summary of the invention]

The present invention projects bright lines of each primary color on the tube surface of a color CRT in a manner that gradually shifts, detects the light intensity of each primary color with optical sensors placed at opposing positions on the tube surface, and determines the convergence state from this light intensity data. For the compa-sense measuring device that measures By calculating the average misconvergence amount by adding and averaging the misconvergence amounts of the phases, highly accurate measurement can be performed without increasing the measurement time.

[Prior technology]

The present applicant previously proposed a phase detection type convergence measuring device (see patent application (5) dated December 8, 1988).

This convergence measuring device has a pattern generator that outputs a video signal to a color CRT that is a measurement target. This pattern generator creates a video signal of a bright line pattern in which the bright lines of each primary color (in the vertical or horizontal direction) are gradually shifted by a constant value in the vertical direction on the tube surface of the color CRT.

An optical sensor is disposed at a position facing the tube surface, and the sensor has a single-peak directional sensitivity characteristic.

The detection output of the sensor is then supplied to a calculation means, and this calculation means calculates the amount of misconvergence from the light intensity data of each primary color.

An optical sensor is placed at an arbitrary position on the screen of the color CRT, and a pattern generator projects bright line patterns for each primary color on the screen of the color CRT.

The calculation means creates an envelope curve for each primary color from the detection output of each primary color of the optical sensor, calculates the position of the peak value of this envelope curve, and calculates the amount of misconvergence by comparing the position of the peak value for each primary color. Calculate.

Then, such measurements are performed multiple times to calculate multiple amounts of misconvergence to determine the convergence state.

[Problem to be solved by the invention]

In the above measurement, the following measurement time is required to calculate - misconvergence amounts. That is, if the number of samplings required to create one of the green, red, and blue envelope curves is 8, and the unit shift time of the bright line is t, then light intensity data is sampled for each of the green, red, and blue bright lines. Therefore, to measure the amount of misconvergence in either the vertical or horizontal direction, T (measurement time) - 3 (three colors) x S (number of samples) x
t (unit shift time).

Here, in order to improve the measurement accuracy, the number of samplings (S
), but as can be seen from the above equation, increasing the number of samplings increases the measurement time, and there is a contradictory relationship between measurement accuracy and measurement time. Note that the unit shift time (1) cannot be made any faster from the viewpoint of the functionality of the device.

Therefore, an object of the present invention is to provide a convergence measuring device that can perform highly accurate measurements without increasing measurement time.

[Means to solve the problem]

To achieve the above object, the convergence measurement device of the present invention is capable of creating a video signal of a bright line pattern in which the bright line of each primary color is gradually shifted in the vertical direction by a fixed value, in multiple phases with different bright line positions, and a pattern generator that repeatedly outputs a video signal of a bright line pattern in a fixed order to a color CRT; an optical sensor disposed at a position facing the screen of the color CRT and having a single-peak directional sensitivity characteristic; a misconvergence amount calculating means for calculating a misconvergence device for each emission line pattern of each phase from the output, and calculating an average misconvergence amount by averaging the misconvergence amount of the newest each phase among the measured data; It is prepared.

[Effect]

When the phases of the bright line pattern are A, B, etc., the pattern generator is driven and the bright line pattern of the A phase, the bright line pattern of the B phase, etc. are generated on the screen of the color CRT for each primary color. The signals are displayed repeatedly in sequence, and the calculation means calculates the amount of misconvergence for each phase based on the detection output of the optical sensor. Further, the calculation means calculates an average amount of misconvergence by adding and averaging the amount of misconvergence of the newest phase among those measured for each measurement. Since this average misconvergence amount is obtained every time each phase is measured, a predetermined number of data can be obtained in a short time, and since it includes the measurement results of all phases, it is highly accurate.

〔Example〕

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

FIG. 2 shows the measurement state of the convergence measuring device A. In FIG. 2, a television receiver B has a built-in color CRT (color cathode ray tube) 1 to be measured, and a tube surface 2 of the color CRT 1 is exposed to the front. Signal cable 3 of convergence measurement device A
is connected to the video signal input terminal of the television receiver B, and an image is projected on the screen 2 of the color CRT 1 by the video signal output from the convergence measuring device A. or,
The convergence measuring device A has an optical sensor 4 connected by a cable, and the sensor 4 is disposed opposite the tube surface 2 at a contact position with the tube surface 2 .

FIG. 3 shows a cross-sectional view showing the positional relationship between the tube surface 2 and the optical sensor 4. In FIG. 3, the tube surface 2 is made up of a fluorescent section 2b arranged on the inner surface of a panel glass 2a, and when the fluorescent section 2b is irradiated with an electron beam, it emits light. Further, the optical sensor 4 is provided with a microswitch SW, and when the optical sensor 4 is brought into contact with the tube surface 2, the microswitch SW is turned on.

Measurement is started by the ON signal of this microswitch SW, and the flowchart shown in FIG. 1θ 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 (degrees) 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 (in degrees) of the incident light on the optical sensor 4 at each incident angle.
Relative light intensity when the light intensity when the incident angle is 0° is taken as 100%. The directional sensitivity characteristics of the optical sensor 4 are maximum when the angle of incidence is 0°, and as the absolute value of the angle of incidence increases, the light intensity decreases and becomes 0% when the absolute value of the angle of incidence is approximately 20°, which is a so-called simple type. exhibits peak characteristics.

FIG. 1 shows a circuit block diagram of a convergence measuring device A. In FIG. In FIG. 1, the detection output (light intensity data) of the optical sensor 4 is sent to an A/D converter 6 via an amplifier 5
and is digitized by the A/D converter 6. The digitized light intensity data is written into the measurement data memory 7 based on a write signal from the CPU 8. C.P.
U8 controls reading and writing of the measurement data memory 7 as well as the calculation memory 9 and the program memory 10. The calculation memory 9 stores calculation data necessary for processing various data. The program memory IO stores data for executing a measurement program, a modulation degree calculation program, a white area change program, a bright line interval automatic correction program, a misconvergence amount calculation program, and a display program.

The contents of each program will be explained together with the following operations. The CPU 8 has a gl adjustment calculation means that is driven according to a modulation degree calculation program and a misconvergence amount calculation means that is driven according to a measurement program. The modulation degree calculation means first restores the maximum value MAX and minimum value MIN of the light intensity data of the primary colors to be measured, and calculates MIN/MA.
The modulation degree F is calculated by executing the equation X=F. If the value of this modulation degree 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 it is determined that it is inappropriate, the modulation degree data is sent to the bright line interval calculation unit II. Further, if the modulation degree value is approximately 0, a white area change command is sent to the white area setting section 12. In this embodiment, the modulation degree calculation means determines the modulation degree from the difference between the maximum value and the minimum value of the light intensity data, but 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) It may also be determined based on the angle of inclination or angle of inclination). The misconvergence amount calculation means performs interpolation processing on the discrete light intensity data (shown in FIGS. 5 and 6) read from the measurement data memory, thereby causing fine changes as shown by the broken lines in FIGS. 5 and 6. Convert to light intensity data (envelope curve), and detect the point (position) at which the peak value of the light intensity data (envelope curve) for each primary color is obtained, for example, the point at which the peak value of green light intensity data is obtained. (position) and the time point (position) at which the peak value of the red and blue light intensity data is obtained, that is, the amount of misconvergence is calculated.

Further, the misconvergence amount calculation means calculates an average misconvergence amount by adding and averaging the latest misconvergence amounts of each phase. In this example, the emission line pattern consists of two phases, the A phase and the 8 phase, as described below, so the amount of misconvergence in the case of the 8 phase or 8 phase of the current measurement and the amount of misconvergence in the case of the 8 phase or A phase of the previous measurement. The average amount of misconvergence is calculated by averaging the amount of convergence. The CPU 8 operates the bright line interval calculation unit 11. in accordance with each program. The white area setting section 12 and the display section 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 screen 2, and if the modulation degree value output from the CPU 8 is a value other than 0.2 to 0.6, Bright line interval data corresponding to the value of the modulation degree is output. White area setting section 1
2 specifies the white area of the screen, and in this embodiment, either the right half or the left half of the tube surface 2 is configured to be set as the white area. When a white area change command is sent from the CPU 8, white area data is output in which the white area is the opposite area. The display section 13 displays the amount of misconvergence, etc.
Furthermore, if the bright line spacing automatic correction program is not available, the value of the modulation degree is displayed in order to manually correct the bright line spacing. Furthermore, signals from the keyboard section 14 are input to the CPU 8. By inputting data from the keyboard section 14, the calculation memory 9. Program memory IO
etc. data can be updated. In addition, when manually correcting the bright line interval, data is inputted 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 generates and outputs a video signal that makes the area specified by the white area data white and makes the other areas a bright line pattern.

The bright line pattern consists of a plurality of red, green, or blue bright lines arranged at regular intervals δ in the vertical direction for each frame by I/N (N is an integer of 2 or more, and in this example As shown in Figure 8, the arrangement of the bright lines changes from the solid line position to the one-dot chain line position to the two-dot chain line position to the three-dot chain line position, as shown in Figure 8. Repeat this arrangement. Further, such a bright line pattern can be created in two phases, i.e., 8-phase and 8-phase, with different bright line positions, and the bright line position of one phase is arranged at an intermediate position with respect to the other. Specifically, for example, if the bright line positions shown in FIG. 8 are in phase 1, the intermediate position of each bright line (the broken line position in FIG. 8) becomes the bright line position in phase 8. and,
The pattern generator 15 sends a bright line pattern of 1 phase for each primary color (red, green, blue), then sends a bright line pattern of 8 phases for each primary color, and repeatedly outputs it in this order. When such a bright line is generated on the tube surface 2, the detection output of the optical sensor 4 is detected at time points A, B, and C at intervals of frame switching time, as shown in FIGS. 5 and 6.

The light intensities at D, a, b, c, d, α, . . . become discrete light intensity data exhibiting characteristics that change in alternating current. Therefore, the optical sensor 4 may be placed at any position with respect to the screen surface 2 of the color CRTl, and the measurement period may be four frame periods (four samplings) in principle. Further, the pattern generator 15 is configured to generate bright lines in the vertical direction shown in FIG. 7 and in the horizontal direction perpendicular to this direction.

Hereinafter, the operation of the above configuration will be explained according to the flowchart of FIG. 10.

When the optical sensor 4 is brought into contact with any location on the tube surface 2 of the color CRTI, the microswitch Sw is turned on. The CPU first executes the modulation degree calculation program by the ON signal of the microswitch SW. That is, bright line interval data from the bright line interval calculating section 1 and white area data from the white area setting section 12 are sent to the pattern generator 15 in response to a control signal from the CPU 8 . The pattern generator 15 creates a video signal based on this data, and an image is displayed on the tube surface 2, for example, as shown in FIG. 7, in which a green bright line of phase A is arranged in addition to the white area.

Then, this bright line shifts every frame, and the light intensity data for each shift (see FIG. 5) is taken into the measurement data memory 7. When the green light intensity data is imported, the modulation degree of the light intensity data is calculated by the modulation degree calculation means, and if the value of this modulation degree is almost zero, the white area change program interrupts and changes the white area. Also, if the value of the modulation degree is outside the range of 0.2 to 0.6, the bright line spacing automatic correction program interrupts and corrects the bright line spacing δ.

When this white area change program and bright line spacing automatic correction program are finished, the modulation degree value will be 0.2 to 0.
If it is within the range of 6, these programs will proceed to the measurement program without interrupting. In this measurement program, green, red, and blue bright lines are sequentially projected on 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. If the modulation degree value in the modulation degree calculation program is within the range of 0.2 to 0.6, the green light intensity data at that time is used as is, and the measurement program only measures red and blue. .

Next, the misconvergence amount calculation program is executed, and the misconvergence amount calculation means calculates the point (position) at which the peak value of the red and blue light intensity data is obtained relative to the point (position) at which the peak value of the green light intensity data is obtained. position), that is, the amount of misconvergence (a,) is calculated.

When the misconvergence Ik(al) of the first measurement is calculated, the display program is executed and the misconvergence amount is displayed on the display unit 13.

When the first measurement is completed, the pattern generator 15 projects an eight-phase bright line pattern, and the light intensity data (see FIG. 6) is taken into the measurement data memory 7 in the same manner as described above, and the amount of misconvergence based on the light intensity data is calculated. (b
, ) is calculated.

Also, the misconvergence amount calculation means is (a++b+)/
Calculate the average amount of misconvergence by calculating the formula 2,
This average amount of misconvergence is displayed on the display section 13.

In this way, the third measurement (A phase bright line pattern),
By performing the fourth measurement (eight-phase bright line pattern), etc., the measurement results as shown in the table below are displayed on the display section 1.
3.

〈Table〉 From the above 〈Table〉, the average amount of misconvergence is obtained for each phase measurement, so a predetermined number of data can be obtained in a short time, and only the first measurement is based on the phase bright line pattern (4 samplings). The amount of misconvergence obtained is the average amount of misconvergence obtained from the A-phase and 8-phase emission line patterns (8 sampling numbers), so the number of samplings was doubled as shown in Figure 9. The result is almost the same as that of , and highly accurate data can be obtained.

In this embodiment, the pattern generator 15 is configured to generate a two-phase bright line pattern of the negative phase and the B phase/phase.
) may be configured to generate a bright line pattern. In this case, the average amount of misconvergence is (A + B +
It is calculated by calculating the formula: C+...)/2.

Furthermore, in this embodiment, the white area setting section 1
The color CRT 2 is configured to set either the right half or the left half of the screen 2 as a white region, but the color CRT 1 is configured to set either the right half or the left half of the screen 2 as a white region, but the color CRT 1 has a high pressure level that is sufficient to suppress high voltage fluctuations in areas other than where the optical sensor 4 is arranged. As long as the range is set as a white area, the size and position of the white area does not matter.

Furthermore, in this embodiment, the pattern generator 15 is configured to arrange a plurality of bright lines at regular intervals, but only one bright line is projected, and this bright line is gradually shifted by a predetermined amount. It may be configured to do so.

〔Effect of the invention〕

As described above, according to the present invention, the bright lines of each primary color are projected on the tube surface of a color CRT in a manner that they gradually shift, and the light intensity of each primary color is detected by optical sensors placed at opposing positions on the tube surface. For a convergence measuring device that measures the convergence state from this light intensity data, multiple phases of bright line patterns are repeatedly projected in a fixed order for bright line patterns that gradually shift the bright lines of each primary color, and the amount of misconvergence is created for each bright line pattern. The configuration is configured to calculate the average amount of misconvergence by adding and averaging the amount of misconvergence for each phase that is the most recent among the measured data, which has the effect of making it possible to perform highly accurate measurements without prolonging the measurement time. .

[Brief explanation of the drawing]

1 to 9 show embodiments of the present invention, FIG. 1 is a circuit block diagram of the convergence measuring device, FIG. 2 is a perspective view showing the measurement state, and FIG. 3 is the position of the tube surface and the optical sensor. A cross-sectional view showing the relationship, Figure 4 is a directional sensitivity characteristic diagram of the optical sensor,
Figure 5 is a diagram showing the light intensity data of the B phase, Figure 6 is a diagram showing the light intensity data of the B phase, Figure 7 is a front view of the television receiver, and Figure 8 is a diagram showing the arrangement of bright lines. , Figure 9 is 2
FIG. 1O, which is a diagram showing light intensity data when the number of samplings is doubled, is a flowchart. A...Convergence measuring device, l...Color CR
T, 2...tube surface, 4...light sensor, 8...cPU
(Misconvergence amount calculation means), 15... pattern generator. 5? Room I, 1 square frame E shows 7 Xu Jushi [d Figure 2 Figure 5 Figure 6 Tube surface and light sensor +j117) Punishment J! 1 degree - 1 degree - 1 n direction pressure/pressure line diagram Figure 4 Front view of television receiver A & Brown Placing of anchor lines 8〒1 factor Figure 8

Claims (1)

[Claims] (1) A video signal of a bright line pattern in which the bright line of each primary color is gradually shifted by a fixed value in the vertical direction can be created in multiple phases with different bright line positions, and the video signal of the bright line pattern of these multiple phases can be repeatedly colored in a fixed order. A pattern generator that outputs to the CRT, an optical sensor that is placed opposite to the tube surface of the color CRT and has a single-peak directional sensitivity characteristic, and a misconvergence for each phase bright line pattern based on the detection output of this optical sensor. A convergence measuring device comprising: a misconvergence amount calculation means for calculating an average misconvergence amount by adding and averaging the misconvergence amount of each latest phase of the measured data.