JPH0576017A - Picture correcting device - Google Patents

Abstract

PURPOSE:To provide the picture correcting device of a direct-view or projection type CRT display device by which a high precise correction can be attained, and an adjusting time can sharply be shortened by providing a photoelectric converting element at an outside, detecting the position and quantity of electronic beams or rays of light, and automatically correcting a picture. CONSTITUTION:This device is equipped with a projecting means which projects a test signal at a prescribed position on the screen of a display means which displays the received picture information of a color television receiver, detecting means 1 which successively detects the test signal, and searches the balance position of each detection signal from the prescribed position on the screen, generating means 3 which generates a correcting signal which corrects the position of the electronic beams or rays of light of the display means by a signal from the detecting means, and driving means 4 which drives the display means by the output from the generating means. Thus, a convergence or a luminance correction can be high precisely and automatically attained with simple constitution, and the complete non-adjustment of the display device can be realized.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for correcting a color television receiver, and more particularly to an image correcting device for automatically making various corrections.

[0002]

2. Description of the Related Art Generally, in a video projector for magnifying and projecting in a screen by using three projection tubes that emit three primary colors, the angle of incidence (hereinafter referred to as the "concentration angle") of the projection tube with respect to the screen is different for each projection. Since the tubes are different, color shift, focus shift, deflection distortion, and brightness change occur on the screen. Each of these corrections uses a method of making an analog correction waveform in synchronism with the horizontal and vertical scanning periods and adjusting by changing the size and shape of this waveform, but there is a problem in terms of correction accuracy. is there. Further, since various corrections are manually observed by visually observing deviations on the screen, there is a problem that adjustment time is required.

Therefore, as a method with high convergence precision, a digital convergence apparatus disclosed in Japanese Patent Publication No. 59-8114 and a method for automatically correcting deflection distortion are disclosed in Japanese Patent Publication No. 58-24186. As a method in which the electron beam deflection control device also automatically corrects the convergence with the budeo projector, as a method of Japanese Patent Publication No.
A digital convergence device disclosed in Japanese Patent No. 7 has been proposed.

FIG. 22 shows a block diagram of a conventional image correction apparatus capable of automatic correction. The detector 60 detects the electron beam position from the index phosphor coated on the surface of the shadow mask 43, and the processor 66 generates signals for convergence correction and geometric distortion correction from this detection signal. The signal from the processing device 66 is supplied to the waveform generating device 52, and the convergence yoke 44 and the deflection yoke 46 are supplied.
Each of the scanning waveforms for driving the pulse generator is generated, and the convergence and the geometric distortion can be automatically corrected.

As described above, the position control of the electron beam such as convergence and geometric distortion can be automatically corrected.

[0006]

However, in the above-mentioned configuration, it is necessary to input various correction data such as brightness and color purity other than the correction of the color shift and the geometric distortion on the screen. However, it has a problem that it takes a lot of time. Further, since the index phosphor is applied to the shadow mask surface in the cathode ray tube, a special cathode ray tube is required, and there is a problem that a detection error occurs in thermal deformation of the shadow mask surface. In addition, a video projector that magnifies and projects using a plurality of projection tubes has a problem that the circuit scale becomes very large because complicated signal processing is required.

In view of the above point, the present invention detects the position and level of an electron beam or light with a two-dimensional photoelectric conversion element, detects the balance position of this detection signal, and automatically corrects it to achieve high precision. It is an object of the present invention to provide an image correction device for a CRT display device, which can significantly reduce the correction and adjustment time.

[0008]

According to a first aspect of the present invention, a detection means for sequentially detecting a test signal on a screen, a calculation means for obtaining a balance position of a detection signal from the detection means, and a calculation signal from the calculation means are provided. According to the above, there is provided a generating means for generating a correction signal for correcting the position of the electron beam or light of the display means.

Further, there is provided means for calculating a balance position where the level of each detection signal is constant.

According to a second aspect of the present invention, a detecting means for sequentially detecting a test signal on the screen and each detection signal from the detecting means are converted into a signal of four quadrants whose polarity is inverted in the scanning direction, and the balance position of this signal is converted. And a generating means for generating a correction signal for correcting the position of the electron beam or light of the display means according to the calculation signal from the calculation means.

According to a third aspect of the present invention, means for sequentially detecting test signals on the screen, first calculating means for obtaining a balance position from a position detection signal from the detecting means, and addition from level detecting signals from the detecting means are added. Second calculating means for obtaining a value,
Means for generating various correction signals in accordance with the signals from the respective calculation means are provided.

Further, there is provided means for detecting the position and level of the light by using the detection signal from the photoelectric conversion element at the position where the test signal is not received as an offset control signal.

[0013]

According to the first aspect of the present invention, the image light from the screen is sequentially detected, the balance position of the detection signal is calculated, and the correction signal for correcting the position is generated by the calculated signal, whereby a simple configuration is achieved. With this, automatic correction can be realized for highly accurate convergence correction. In addition, various types of C from direct-view type to projection type
It is easily compatible with RT display devices.

According to the second aspect of the invention, the image light from the screen is sequentially detected, the balance position of the detection signal of the four quadrants is calculated, and the correction signal for correcting the position is generated by the calculated signal. Highly accurate convergence correction can be realized automatically with a very simple configuration.

According to the third aspect of the invention, the position and amount of the image light from the screen are detected, and various correction signals are created and corrected by the detection signals, so that the convergence and the brightness are automatically adjusted with high accuracy. Since it can be corrected, the display device can be completely adjusted.

[0016]

1 is a block diagram of an image correction apparatus according to a first embodiment of the present invention. (FIG. 2) is a block diagram of the detection unit 1 of (FIG. 1).

In FIG. 1, 1 is a plurality of 2 for detecting the positions of electron beams and light on the screen of the cathode ray tube 40.
Detecting unit 2 composed of a three-dimensional photoelectric conversion element, 2 is a detecting unit 1
Is a sequential enlargement control unit for controlling the detection position for sequentially detecting the test signal and 3 is a correction signal creation unit for creating a correction signal from the detection signal from the detection unit 1. Reference numeral 4 is a deflection unit for creating a deflection waveform synchronized with the synchronization signal from the input terminal 50, reference numeral 48 is an input terminal to which a video signal is supplied, and reference numeral 5 is for controlling the amplitude or the like of the video signal from the input terminal 48. The display unit 6 is a test signal generation unit for generating a test signal for displaying the test signal on the screen of the cathode ray tube 40.

The operation of the image correcting apparatus of this embodiment having the above-mentioned structure will be described below.

A synchronizing signal is input to the input terminal 50, a correction current for raster-scanning the screen is created by the deflection unit 4, and the correction current is supplied to the deflection yoke 46 and the convergence yoke 44 to control the scanning speed. Input terminal 4 on display 5
The video signal from 8 is input and various kinds of signal processing and amplification for driving the cathode electrode of the cathode ray tube (hereinafter referred to as CRT) 40 in the display unit 5 are performed. Further, the test signal from the test signal generating section 6 is supplied to the display section 5, switched between the video signal and the test signal and applied to the CRT 40.

The detector 1 is composed of twelve two-dimensional photoelectric conversion elements S1 to S12 as shown in FIG.
The light of the test signal on the detection unit 1 is converted into the photoelectric conversion element S1.
After the light reception and photoelectric conversion in S12, position detection and measurement are performed to calculate the balance position of each color signal. From this calculated signal, the correction signal creation unit 3 creates an optimum correction waveform for correcting convergence and geometric distortion. The correction waveform from the correction signal generation unit 3 is supplied to the deflection unit 4 for controlling scanning and is corrected.

As described above, the image light from the screen is sequentially detected, the balance position of the detection signal is calculated, and the correction signal for correcting the position is created by the calculated signal, thereby converging or geometric distortion. Can be automatically corrected.

Next, a block diagram (FIG. 3) and a waveform diagram (FIG. 4) will be used to explain the control means in detail. The detection unit 1 includes a plurality of photoelectric conversion elements 11, an addition circuit 11a, a level comparison circuit 12, and a measurement circuit 13, and a deflection unit 4
Is composed of a screen amplitude / deflection distortion correction circuit 9 and a convergence correction circuit 10, and the correction signal generation unit 3 is composed of a correction signal generation circuit 14 and an arithmetic processing circuit 15.

FIG. 4 (a) shows an overall configuration diagram of the photoelectric conversion element 11. As shown in FIG. 4A, twelve photoelectric conversion elements (S1 to S12) 11 are arranged in a cross shape. When the detection area 18 of the adjustment point on the display screen shown in FIG. 4D is enlarged, the test signal 17 generated from the test signal generator 6 on the photoelectric conversion element 11 as shown in FIG. Is projected. The twelve signals photoelectrically converted by the photoelectric conversion element 11 are supplied to the addition circuit 11a, and the signal obtained by converting the time axis into voltage information is compared with the level of each photoelectric conversion element by the level comparison circuit 12, It is input to the measurement circuit 13. The measuring circuit 13 measures the levels of the reference signal (the test signal 17 in FIG. 4A) and the focus signal (the test signal 16 in FIG. 4A). Measuring circuit 13
Is supplied to the arithmetic processing circuit 15 to calculate an optimum correction amount, and the correction signal generating circuit 14 creates a correction signal based on this data.

The arithmetic processing circuit 15 is composed of a CPU or the like, and controls the test signals of the respective colors in the test signal generator 6, compares the level-detected data, and controls the sequential enlargement controller 2. You are controlling the signal.

Next, in order to explain the convergence operation of convergence in detail, as shown in FIG. 4A, the reference test signal 17 (eg G signal) is replaced with the test signal 16 (eg R signal).
The case of focusing the B signal) will be described.

The photoelectric conversion elements (S4, S5, FIG. 4A)
Each signal photoelectrically converted in (S8, S9) is added by the addition circuit 11
Each is added at a. When it exists at a target position for each photoelectric conversion element like the test signal 17 of (FIG. 4A), the output from the adder circuit 11a has a constant level as shown in (FIG. 4B). An addition output is obtained. When the photoelectric conversion element does not exist at a target position like the test signal 16 in FIG. 4A, the output from the adder circuit 11a is
As shown in FIG. 4 (c), a constant level addition output cannot be obtained. That is, it means that the position of the test signal can be obtained depending on the level of each photoelectric conversion element.

Therefore, it is output from the adder circuit 11a.
The signal shown in FIG. 4C is used as a reference by the level comparison circuit 12.
The levels shown in FIG. 4B are compared, and the level of this comparison signal is accurately measured by the measuring circuit 13. Measuring circuit 13
The signal measured in 4 is supplied to the correction signal generation circuit 14 through the arithmetic processing circuit 15, and the test signal 16 of FIG.
A convergence correction waveform for focusing on the test signal 17 and a correction waveform for controlling deflection distortion, screen amplitude, etc. are created.

In this embodiment, as shown in FIG. 4 (a), the correction means for only one representative point among the plurality of adjustment points has been described, but in order to correct the entire screen, (Fig. 4
Dynamic correction can be realized by sequentially detecting the information from each adjustment point shown in (d) by the photoelectric conversion element 11.

The positional deviation amount can be determined by the digital convergence method, as described in the conventional example, and its basic block diagram is shown in FIG. The configuration is such that an address generation circuit 19 for creating various address signals from a synchronization signal, a memory 20 for storing data of each adjustment point, and an interpolation circuit 2 for performing data interpolation between the adjustment points.
1, a D / A converter 22 for converting the interpolated data into an analog quantity, and an LP for smoothing the analog quantity
It is composed of an F (low pass filter) 23.

As described above, in the deflection unit 4, the deflection linearity is corrected by the correction linearity correction waveform and the screen amplitude correction data so that the display areas of the respective colors are uniformly positioned over the entire screen. It is driving. Further, the convergence correction is performed by driving the convergence yoke with the correction waveform and data of the color misregistration so that the display areas of the respective colors are located at the same position over the entire screen.

Next, the block diagram of FIG. 6 and the flowchart of FIG. 7 will be used to describe the detection means in detail. The projection of the test signal, the enlargement detection position of the photoelectric conversion element, and the control of the data processing of the photoelectric conversion signal are all intensively controlled by the control signal of the arithmetic processing circuit 15. In order to explain this operation, description will be given according to (FIG. 7).

First, an adjustment point (for example, adjustment point E3) to be adjusted on the display screen is selected. Secondly, the test signal generation circuit 6 is controlled based on this information to display the test signal on the display screen.

Thirdly, the position of the test signal displayed on the screen is detected by the photoelectric conversion element. Fourth, it is determined whether the test signal and the detected address position are the same.

Fifth, if the determination results are the same, data detection, which is the position detection of the test signal on the screen, is performed.

Sixth, data processing is performed to create a correction waveform for focusing based on the data detection result.

Seventh, the drive system is controlled by the correction waveform to execute the correction. Eighth, detect the test signal on the screen to see if it is focused.

When the above operation is completed, the correction is completed. Also, as a result of determining whether the fourth test signal and the detected address position are the same, if different, the operation from the first is repeated. The adjustment of the entire screen can be realized by performing the above-mentioned operation at each of the adjustment points A1 to E6 shown in FIG.

As described above, the arithmetic processing circuit 15 determines whether the display of the test signal is the same as the display area on the screen by moving the detection area of the photoelectric conversion element, and controls this. Is a sequential enlargement control unit 2 including a discrimination circuit 25 and a position control circuit 24. As described above, according to this embodiment, the image light from the screen is sequentially detected, the balance position of the detection signal is calculated, and the correction signal for correcting the position is generated by the calculated signal, thereby providing a simple configuration. With, it is possible to realize highly accurate automatic convergence correction. Further, it can be easily applied to various types of CRT display devices from direct-view type to projection type. Further, by providing a plurality of adjustment points on the screen and interpolating data between the adjustment points to create a correction waveform, stable and highly accurate correction can be realized.

FIGS. 8 to 10 show an image correction apparatus according to the second embodiment of the present invention. The difference from the configuration of the first embodiment is that the balance positions of the detection signals in the four quadrants are calculated, and a correction signal is created based on this calculation signal for automatic correction.

In FIG. 8, reference numeral 26 is a detector for detecting the position and level of the image light from the display screen, and 27 is a four quadrant in which the polarity is inverted in each scanning direction from the detection signal from the detector 26. It is a 4-quadrant addition processing unit for converting into a signal. It should be noted that, in (FIG. 8), components performing the same operations as those in the first embodiment are designated by the same reference numerals and the description thereof will be omitted.

FIG. 9 shows an enlarged view of the test signal received by the detector 26. The detection unit 26 of (FIG. 8) is composed of 12 photoelectric conversion elements as shown in (FIG. 9), and the test signal 8 is received on the photoelectric conversion elements (S4, S5, S8, S9). .. The photoelectric conversion signal from the detection unit 26 configured by a photoelectric conversion element is supplied to the 4-quadrant addition processing unit 27, the signal in the 1-quadrant is converted into a signal in the 4-quadrant, position detection and measurement are performed, and the balance position of each color signal is calculated. is doing. From this calculated signal, the correction waveform creating unit 3 creates an optimum correction waveform for correcting convergence and geometric distortion. The correction waveform from the correction waveform creation unit 3 is applied to the deflection unit 4 for controlling scanning.
Is supplied to and corrected.

Next, in order to explain the signal conversion of the four quadrants in detail, the operation characteristic diagram of the four quadrant addition processing unit 27 is used in FIG.

The converted signal received by the horizontal photoelectric conversion element of FIG. 9 is positive (+) in the left photoelectric conversion element (S4, S8) as shown in FIG. 10 (a). The photoelectric conversion elements (S5, S9) on the left are converted into signals, and are converted into signals of negative polarity (-). The converted signal received by the vertical photoelectric conversion element of (FIG. 9) is converted into a negative (−) signal in the upper photoelectric conversion element (S4, S5) as shown in (FIG. 10 (b)). The photoelectric conversion elements (S8, S9) are converted into a positive (+) signal. The converted signals in the horizontal and vertical directions are added and converted into a final four-quadrant signal shown in FIG. 10 (c).
That is, when the test signal exists at the target position in FIG. 9, the photoelectric conversion signal converted into the four quadrants becomes zero (0). Therefore, in the subsequent processing, the convergence correction can be performed by controlling the converted signal so that the converted signal converges to zero (0).

The difference from the first embodiment is that the photoelectric conversion signals are controlled to be constant in the first embodiment, whereas the signals converted into four quadrants are used in the second embodiment. Is controlled to be zero (0). Therefore,
Only one system of the signal whose control system is converted into four quadrants will be targeted. In addition, even when unnecessary light from the outside is incident on the detection unit, a method that does not cause a calculation error with respect to correlated information, particularly in a video projector that performs large-screen display using a plurality of projection tubes. Is a very effective method.

As described above, according to this embodiment, the image light from the screen is sequentially detected, the balance position of the detection signal of the four quadrants is calculated, and the correction signal for correcting the position is created by the calculated signal. As a result, since there is only one control system, highly accurate convergence correction can be realized automatically with a simple configuration. Further, it can be easily applied to various types of CRT display devices from the direct-view type to the projection type, and is particularly effective for the projection type.

Next, an image correction apparatus according to the third embodiment of the present invention will be described. (FIG. 11) to (FIG. 18) show an image correction apparatus according to the third embodiment of the present invention. The difference from the configuration of the first embodiment is that the balance position is calculated from the position detection signal, the added value is calculated from the level detection signal, and various correction signals are created by this calculation signal to perform automatic correction. That is the point.

In FIG. 11, 28 is a detection unit for detecting the position and level of the image light from the display screen, and 29 is a balance position calculation for calculating the balance position from the position detection signal from the detection unit 28. Reference numeral 43 denotes a calculation unit including a balance position calculation unit 29 and an addition value calculation unit 31, 31 denotes an addition value calculation unit that calculates an addition value from a level detection signal from the detection unit 28, and 30 denotes a correction signal generation unit 3. Is a signal processing unit for correcting the video signal by the correction signal of. In FIG. 11, the same operations as those in the first embodiment are designated by the same reference numerals and the description thereof will be omitted.

FIG. 12 shows an enlarged view of the test signal received by the detector 28. The detection unit 28 of (FIG. 11) is (FIG. 9).
The test signal 8 is formed on the photoelectric conversion elements (S4, S5, S8, S9).
Is received. The photoelectric conversion signal from the detection unit 28 including a photoelectric conversion element is supplied to the balance position calculation unit 29 and the addition value calculation unit 31. The balance position calculation unit 29 calculates the balance position from the position detection signal, and the addition value calculation unit 31 calculates the addition value from the level detection signal. From this calculated signal, the correction signal creating unit 3 creates an optimum correction waveform for correcting convergence, geometric distortion, and the signal system. The correction waveform of the position information from the correction signal creation unit 3 is supplied to the deflection unit 4 for controlling scanning and is corrected, and the correction waveform of the level information from the correction waveform creation unit 3 is used for controlling the signal. It is supplied to the signal processing unit 30 and is corrected.

In order to describe the image correction apparatus of this embodiment in detail, a correspondence diagram showing the relationship between the detection target (FIG. 13) and each correction is used. The position and amount of the image light projected on the screen of the CRT 40 (FIG. 11) is calculated by the detector 28 and the calculator 43.

As shown in FIG. 13, the detection target and its relation correspond to the correction of convergence and geometric distortion in the light position detection, and the beam landing, uniformity and white balance in the light amount (level) detection. It corresponds to the correction of. Therefore, the signal from the calculation unit 43 in which the position and amount of light have been calculated is supplied to the correction signal generation unit 3 and various correction signals are generated.

The correction signal from the correction signal generation unit 3 is supplied to the deflection unit 4 and the signal processing unit 30, and the deflection unit 4 receives the convergence correction signal for correcting the color misregistration and the deflection linearity. A deflection correction signal is provided to correct geometric distortion. Further, the signal processing unit 30 includes a beam landing correction signal for correcting a chromaticity change due to the influence of the earth's magnetism, a uniformity correction signal for correcting a brightness unevenness caused by a CRT, a floor of a low light or a highlight. A white balance correction signal for correcting the tonality balance is supplied, and various corrections shown in FIG. 13 are automatically corrected according to the position and amount of image light.

As described above, various corrections can be automatically performed by detecting the position and amount of the image light from the screen and obtaining various correction signals from this detection signal.

Next, the block diagram of FIG. 14 is used to explain the control means in detail. First, the detection unit 26
Is composed of a photoelectric conversion element for detecting the position and amount of light, and the calculation section 43 is an addition circuit 41 for adding photoelectric conversion signals from the detection section 26, a level determination circuit 42 for performing level determination, and a measurement. The signal processing unit 30 includes a circuit 35.
Is composed of a uniformity correction circuit 71, a DC reproduction circuit 72, a gain control circuit 73, and a landing correction circuit 74.

Since the operations of convergence correction and geometric distortion correction are the same as those in the first embodiment, the signal processing section 30 will be described in detail.

First, in order to explain the balance position calculating method, the block diagram of FIG. 15 and the characteristic diagram of FIG. 16 are used.

As shown in FIG. 12 on the screen of the CRT 40, a test signal is projected on the photoelectric conversion element, and the position of this light is photoelectrically converted by the photoelectric conversion elements 32 to 35 in FIG. The signals photoelectrically converted by the photoelectric conversion elements 32 to 35 are supplied to the comparators 36 to 38 and compared with the reference potential. The comparison outputs from the comparators 36 to 38 are supplied to the discrimination circuit 39 to discriminate whether or not the respective photoelectric conversion signals are at the same position.

Therefore, when the test signal 8 exists at a position symmetrical with respect to the positions of the photoelectric conversion elements (S4, S5, S8, S9) as shown in (FIG. 12), the photoelectric conversion of (FIG. 16) is performed. As shown in the output characteristic diagram, the determination result of a constant value is obtained. That is, the balance position calculation method is a method of calculating a position where the positions of the test signals received on the respective photoelectric conversion elements are balanced.

Next, the block diagram of FIG. 17 and the characteristic diagram of FIG. 18 will be used to explain the method of calculating the added value.

As shown in FIG. 12 on the screen of the CRT 40, a test signal is projected on the photoelectric conversion element, and the position of this light is photoelectrically converted by the photoelectric conversion elements 32 to 35 (FIG. 17). The signals photoelectrically converted by the photoelectric conversion elements 32 to 35 are supplied to the adder 40 and added. The addition output from the adder 40 is supplied to the discriminating circuit 39 to discriminate at which level the added value of each photoelectric conversion signal is. Therefore, as shown in (FIG. 12), the test signal 8 is transferred to the photoelectric conversion element (S
4, S5, S8, S9) at the target position, the conversion signals of the photoelectric conversion elements 32 to 35 are added as shown in the characteristic diagram of the photoelectric conversion output of (FIG. 18). The determination result of the value will be obtained. That is, the method of calculating the sum of the levels of the test signals received on each photoelectric conversion element is the addition value calculation method.

The balance position calculation is adopted for the convergence correction and the geometric distortion correction caused by the position, and the addition value calculation is adopted for the luminance correction caused by the level. The calculated data is sampled and held at each screen position, converted into a DC potential, and then supplied to the correction waveform creation unit 3 to create a correction signal corresponding to the amount of light.

Next, various correction operations in the signal processing unit 30 will be described with reference to the block diagram of FIG.

The white balance correction for explaining the first white balance correction is CR
The color balance for each gradation due to the emission characteristics of T40 is corrected, a test signal of each gradation is projected on the screen of the CRT 40, and the amount of light of each gradation is detected by the photoelectric conversion element 26. The level of the signal photoelectrically converted by the photoelectric conversion element 26 is calculated by the calculator 43, and the calculated signal is supplied to the correction signal generator 3. The correction signal creation unit 3 creates a low-light correction signal with a 0% or 25% signal of the black level signal and a highlight correction signal with a 75% or 100% signal of the white level signal. The low light correction signal is supplied to the DC reproduction circuit 72 to drive the RGB driving the CRT 40.
Controls signal cutoff. Further, the highlight correction signal is supplied to the gain control circuit 73 to control the amplitude of the RGB signal that drives the CRT 40, so that the white balance can be automatically corrected.

Secondly, the case of correcting the uniformity will be described. Uniformity correction is a CRT
This is to correct the variation in the brightness in each part of the screen due to the above.
The amount of light of each part is detected by the photoelectric conversion element 26. The signal photoelectrically converted by the photoelectric conversion element 26 is calculated by the calculation unit 4
The level at each correction point is calculated in 3, and the calculated signal is supplied to the correction signal creation unit 3. The correction signal creation unit 3 creates a correction signal for each adjustment point. This correction signal is supplied to a uniformity correction circuit 71 that multiplies a video signal and a correction waveform to create a modulated video signal, and automatically controls a uniform screen by controlling the amplitude of each part of the RGB signal that drives the CRT 40. Uniformity correction for display can be performed.

Third, the case of correcting the beam landing will be described. The beam landing correction is to correct the deterioration of the color purity of each part of the screen due to the earth's magnetism.
The amount of light of each part is detected by the photoelectric conversion element 26. The signal photoelectrically converted by the photoelectric conversion element 26 is
The calculation unit 43 calculates the levels in the central portion and the peripheral portion of the screen, and the calculated signal is supplied to the correction signal generation unit 3.
In the correction signal creation unit 3, the electron beam of the CRT 40 is set to X,
A correction signal is created for each part that maximizes the amount of light of each color by moving in the Y and Z axis directions. For this correction signal, when correcting the center axis of the screen, each surface of the outer frame in the receiver is covered with a coil and the X, Y, and Z axis geomagnetic canceling method is used. Then, the position of the electron beam of the RGB signals supplied to the landing correction circuit 74 such as the peripheral correction method and driven to the CRT 40 is controlled to automatically correct the beam landing for displaying a uniform screen. it can.

As described above, in addition to the convergence and geometric distortion correction by detecting the position of light, the amount of light is detected and beam landing correction, uniformity correction, and white balance correction are performed to uniformize an image. Automatic correction can be realized.

Next, the detection signal from the photoelectric conversion element at the position where the test signal is received is used as an offset control signal.
In order to explain the method of detecting the position and level of light in detail, the block diagram of FIG. 19 and the enlarged view of the detection unit of FIG. 20 are used.

In FIG. 19, 75 is a detection unit composed of a plurality of photoelectric conversion elements as shown in FIG. 20, and 76 is a detection unit.
20 is an external light detection unit for detecting unnecessary light by the photoelectric conversion element in which the test signal 8 is not received in FIG.
In the detection unit 75 of FIG. 20, the photoelectric conversion elements S4, S
5, S8, S9 are sensors for receiving a test signal, and are photoelectric conversion elements S1, S2, S3, S6, S7, S.
Reference numerals 10, S11, S12 are sensors for detecting unnecessary light other than the test signal. Therefore, even when the test signal is received on the photoelectric conversion element shown in FIG. 20, the photoelectric conversion signal becomes the photoelectric conversion output of FIG.

First, considering the horizontal direction of the photoelectric conversion elements S3 to S6, the photoelectric conversion element S from which the test signal is received.
The converted outputs on the S4 and S5 are large, and the converted outputs on the photoelectric conversion elements S3 and S6 which receive unnecessary light are small. Further, considering the vertical direction of the photoelectric conversion elements S1, S4, S8, S11, the photoelectric conversion element S receiving the test signal is detected.
The conversion outputs on S4 and S8 are large, and the conversion outputs on the photoelectric conversion elements S1 and S11 that receive unnecessary light are small.
The external light received by other than the photoelectric conversion elements S4, S5, S8, S9 is detected by the external light detection unit 76 (FIG. 19), and the detection of this unnecessary light is supplied to the calculation unit 43, and the detection error is detected. Used as an offset signal to correct
The converted signal before the correction of 1) is calculated from the corrected signal after the unnecessary light is removed. Therefore, even when unnecessary light enters the photoelectric conversion element, highly accurate detection and correction can be realized.

As described above, according to this embodiment, the position and amount of the image light from the screen are detected, and various correction signals are generated and corrected by the detection signals, so that the drift and the fluctuation are highly accurate. Since it is possible to automatically correct even for such cases, the display device can be completely adjusted. Further, by creating a correction waveform using the detection signal from the photoelectric conversion element at the position where the test signal is received as an offset control signal, stable and highly accurate correction can be realized.

In the first to third embodiments, the display device using the CRT is described for easy understanding, but it goes without saying that other display devices are also effective.

Further, in the first to third embodiments, the case where the detecting section has the two-dimensional photoelectric conversion elements arranged in a cross shape has been described, but it goes without saying that other detecting elements and arrangements are also effective. Yes.

Further, in the first to third embodiments, the case where the enlargement control means is sequentially provided as means for matching the projection of the test signal with the detection area has been described, but other control means are also effective. Needless to say.

Further, in the first to third embodiments, the case where the display screen is detected from the outside has been described as the light detection method. However, in the direct-view type, the detection element is applied to the shadow mask surface to detect the light. Needless to say, the projection type is also effective for detecting means for direct detection, such as a method of applying a detection element to the screen surface for detection.

[0074]

As described above, according to the first invention, the image light from the screen is sequentially detected, the balance position of the detection signal is calculated, and the correction signal for correcting the position is generated by the calculated signal. By doing so, automatic correction can be realized for highly accurate convergence correction with a simple configuration. Further, it can be easily applied to various types of CRT display devices from direct-view type to projection type.

According to the second invention, the image light from the screen is sequentially detected, the balance position of the detection signal of the four quadrants is calculated, and the correction signal for correcting the position is created by the calculated signal. With a very simple structure, highly accurate convergence correction can be realized automatically. Even when unnecessary light is incident, unnecessary signals having a correlation are automatically removed, so that highly accurate correction can be realized.

According to the third aspect of the invention, the position and amount of the image light from the screen are detected, and various correction signals are created and corrected by this detection signal, so that the convergence and the brightness are automatically adjusted with high accuracy. Since it can be corrected, the display device can be completely adjusted. In addition, by detecting unnecessary light with the photoelectric conversion element that does not receive the test signal and using this detection signal as an offset signal to correct the detection error, highly accurate correction can be realized and its practical effect is great. ..

[Brief description of drawings]

FIG. 1 is a block diagram of an image correction apparatus according to a first embodiment of the present invention.

FIG. 2 is a configuration diagram of a detection unit for explaining the operation of the embodiment.

FIG. 3 is a block diagram for explaining the operation of the embodiment.

4A is a configuration diagram of a detection unit for explaining the operation of the embodiment, FIG. 4B is a characteristic diagram, FIG. 4C is a characteristic diagram, and FIG. 4D is a plan view showing the display screen.

FIG. 5 is a block diagram for explaining the operation of the embodiment.

FIG. 6 is a block diagram for explaining a control system operation of the embodiment.

FIG. 7 is a flowchart for explaining the control system operation of the same embodiment.

FIG. 8 is a block diagram of an image correction apparatus according to a second embodiment of the present invention.

FIG. 9 is a configuration diagram of a detection unit for explaining the operation of the embodiment.

FIG. 10A is a horizontal photoelectric conversion output characteristic diagram of the four-quadrant addition process of the same embodiment. FIG. 10B is a vertical photoelectric conversion output characteristic diagram of the four-quadrant addition process of the same embodiment. Photoelectric conversion output characteristic diagram of 4-quadrant addition processing

FIG. 11 is a block diagram for explaining the operation of the embodiment.

FIG. 12 is a configuration diagram of a detection unit for explaining the operation of the embodiment.

FIG. 13 is a relational diagram for explaining the operation of the embodiment.

FIG. 14 is a block diagram for explaining the operation of the embodiment.

FIG. 15 is a block diagram for explaining the operation of balance position calculation processing according to the embodiment.

FIG. 16 is a characteristic diagram for explaining the operation of the balance position calculation process of the embodiment.

FIG. 17 is a block diagram for explaining the operation of additional value calculation processing according to the embodiment.

FIG. 18 is a characteristic diagram for explaining the operation of the additional value calculation process of the same embodiment.

FIG. 19 is a block diagram of an image correction apparatus according to a third embodiment of the present invention.

FIG. 20 is a configuration diagram of a detection unit for explaining the operation of the embodiment.

FIG. 21A is a horizontal photoelectric conversion output characteristic diagram of the same embodiment. FIG. 21B is a vertical photoelectric conversion output characteristic diagram of the same embodiment.

FIG. 22 is a block diagram of a conventional image correction device.

[Explanation of symbols]

 1, 26, 28, 75 Detection unit 2 Sequential enlargement control unit 3, 77 Correction waveform creation unit 4 Deflection unit 6 Test signal generation unit 26 4 Quadrant addition processing unit 29 Balance position calculation unit 30 Signal processing unit 31 Addition value calculation unit 40 Cathode ray tube 43 Calculation unit 76 External light detection unit

Claims (5)

[Claims] 1. A display unit for displaying image receiving information of a color television receiver, a projecting unit for projecting a test signal at a predetermined position on the screen of the display unit, and the sequential detection of the test signal, and Detecting means for obtaining a balance position of each detection signal from a predetermined position on the screen; generating means for generating a correction signal for correcting the position of the electron beam or light of the display means by the signal from the detecting means; An image correction apparatus comprising: a driving unit that drives the display unit by an output from the generating unit. 2. The image correction apparatus according to claim 1, wherein the detection means calculates a balance position where the level of each detection signal is constant. 3. A display means for displaying image receiving information of a color television receiver, a projecting means for projecting a test signal at a predetermined position on the screen of the display means, and a detecting means for sequentially detecting the test signal. Calculating means for converting each detection signal from a predetermined position on the screen into a four-quadrant signal in which the polarity is inverted in each scanning direction based on the output from the detecting means, and calculating a balance position of the signal. It is characterized by further comprising: generating means for generating a correction signal for correcting the position of the electron beam or light of the display means based on the signal from the calculating means; and drive means for driving the display means by the output from the generating means. Image correction device. 4. A display means for displaying image receiving information of a color television receiver, a projecting means for projecting a test signal at a predetermined position on the screen of the display means, and a detecting means for sequentially detecting the test signal. First calculating means for obtaining a balance position from each position detection signal from a predetermined position on the screen, and second calculating means for obtaining an added value from each level detection signal from the predetermined position on the screen, Generating means for generating a correction signal for correcting the position and level of the electron beam or light of the display means by the signals from the first and second calculating means, and the display means driven by the output from the generating means. An image correction device comprising: 5. The image correction apparatus according to claim 4, wherein the detection means detects the position and level of the light by using the detection signal from the photoelectric conversion element at the position where the test signal is not received as an offset control signal. ..