JP3407473B2 - Cathode ray tube controller - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cathode ray tube control device for detecting a two-dimensional position of a scanning electron beam of a cathode ray tube and correcting geometrical distortion and convergence of an image.

[0002]

2. Description of the Related Art In order to automatically correct various geometric distortions such as geometric distortion and convergence distortion of an image projected by a cathode ray tube, the two-dimensional position of the scanning electron beam of the cathode ray tube is detected and the detected result is detected. Japanese Patent Publication No. 1-48553 proposes a cathode ray tube control device having a feedback loop configured to correct geometric distortion.

FIG. 14 shows a block diagram of a conventional cathode ray tube control device. In FIG. 14, reference numeral 1 is a phosphor screen of a cathode ray tube, 2 is a shadow mask of the cathode ray tube, 3 is an index phosphor coated on the shadow mask, 4 is an electron beam of the cathode ray tube attached to a neck portion of the cathode ray tube. A scanning deflection / convergence yoke 100 is a detection means for detecting the two-dimensional position of the scanning electron beam.

In the detection means 100, 101 is a photoelectric conversion circuit for photoelectrically converting the light emitted from the index phosphor 3, 102 is an amplification circuit for amplifying the electric signal output by the photoelectric conversion circuit 101, and 103 is an output for the amplification circuit 102. A binarization circuit that binarizes the generated electric signal into a detection pulse, 1
04 measures the interval of the detection pulse and converts it into a voltage (Time-V
A TV conversion circuit for performing an oltage conversion), and an A / D conversion circuit 105 for A / D converting the voltage converted by the TV conversion circuit 104. A geometric distortion correction circuit 300 receives geometric distortion correction data 401 from a memory 400, which will be described later, generates a correction waveform and outputs it to the deflection / convergence yoke 4 to correct the geometric distortion of the cathode ray tube.
00 is a memory for storing the geometric distortion correction data 401 corresponding to the position of the image projected by the cathode ray tube as a two-dimensional array,
Reference numeral 600 is a detection signal generation circuit for generating a test pattern used for applying the scanning electron beam to the index phosphor 3 when the detection means 100 detects the two-dimensional position of the scanning electron beam, and 700 is a detection signal generation circuit. 600
Or the output of the video signal processing circuit 800 to be described later.

Reference numeral 800 is a video signal processing circuit for processing the image displayed on the cathode ray tube. Further, 200 is the detection means 1
This is an arithmetic / control circuit that obtains the geometric distortion correction data 401 stored in the memory 400 from the digital signal output from 00 and controls the switching circuit 700.

The operation of the conventional cathode ray tube control device configured as described above will be described with reference to FIG.

In FIG. 15A, the index phosphor 3 applied on the shadow mask 2 in FIG.
It is an array diagram when it sees from the side. 15 (b) is an enlarged view of FIG. 15 (a).

When detecting the two-dimensional position of the electron beam,
As shown in FIG. 15B, the test pattern 10 output from the detection signal generating circuit 600 is displayed on the index fluorescent body 3 on the cathode ray tube.

When the index phosphor 3 is exposed to the test pattern, light or ultraviolet rays are generated and converted into an electric signal by the photoelectric conversion circuit 101 to obtain a detection signal as shown in FIG. 15 (c).

The detection signal is amplified by the amplifier circuit 102 and input to the binarization circuit 103. Binarization circuit 103
Then, binarization processing is performed from the threshold voltage indicated by reference numeral 39 in FIG. 15C to generate the detection pulse shown in FIG. 15D.

On the other hand, the test pattern 10 is shown in FIG.
It is generated at the timing shown in (e). Therefore, the two-dimensional position of the electron beam can be detected in the horizontal direction by measuring th in FIG. 15D, and can be detected in the vertical direction by measuring tv.

The TV conversion circuit 104 outputs the result obtained by measuring the th and tv as a voltage. The above operation will be described by taking th as an example. The pulse shown in FIG. 15 (f) is created from the pulse shown in FIG. 15 (d) and FIG. 15 (e). Figure 15
Although not shown in the figure while the pulse (f) is being input, the voltage of the capacitor changes as shown in FIG. 15 (g) by passing a constant current through the capacitor. Therefore, FIG.
The vh in (g) becomes the output after TV conversion.

The TV conversion of tv can be similarly obtained.
The voltage output from the TV conversion circuit 104 is converted into a digital signal by the A / D conversion circuit 105 and given to the arithmetic control circuit 200.

The arithmetic control circuit 200 uses the result of detecting the two-dimensional position of the scanning electron beam as described above to obtain the geometric distortion correction data 4 so as to obtain a predetermined detection result.
01 is generated and output to the geometric distortion correction circuit 300.

As described above, in the conventional cathode ray tube controller, the geometrical distortion of the cathode ray tube is automatically corrected.

On the other hand, the uneven brightness of the image projected by the cathode ray tube is known as the uniformity of the brightness of the cathode ray tube. The uniformity of the brightness can be confirmed most noticeably when an all-white image is displayed on the cathode ray tube. A method is generally known in which a luminance modulation circuit is added to a video signal processing circuit in order to correct the luminance uniformity so that the luminance level of the video signal is modulated. There are many cathode ray tube control devices that require a high level of fidelity of the image projected on the cathode ray tube, such as the cathode ray tube control devices that are installed in monitors for video signals used in broadcasting stations and production. In this case, the brightness modulation circuit as described above is used.

However, the brightness modulation circuit is used only for correcting the uniformity of the brightness of the cathode ray tube, and has not been used for the purpose of improving the performance in the automatic correction of the geometrical distortion.

[0018]

In order to accurately correct the image projected by the cathode ray tube, it is necessary to be able to detect the stable two-dimensional position of the electron beam anywhere in the projected region.

However, in the configuration of the conventional example, the detection pulse is stably detected at a certain point on the screen due to factors such as variations in the sensitivity of the detector, uniformity characteristics with respect to the incident angle, and uneven coating of the index phosphor coated on the shadow mask. Even if it is obtained, it is not always possible to obtain a stable detection pulse at other points, and as a result it is very difficult to detect a stable two-dimensional position of the electron beam anywhere in the area of the cathode ray tube. There was a problem.

Further, a method of increasing the number of detectors, such as assigning a specific detector to a part where the detection is not stable, has been conventionally used, but the cost increases due to the increase in the number of detectors, and the balance adjustment of each detector is troublesome. There was a problem that it took too long.

In view of the above point, an object of the present invention is to provide a cathode ray tube control device for detecting a stable two-dimensional position of an electron beam anywhere in a region where a cathode ray tube is projected.

It is another object of the present invention to provide a cathode ray tube control device capable of detecting a stable two-dimensional position of an electron beam anywhere in the area of the cathode ray tube where the number of detectors is small. .

[0023]

According to a first aspect of the present invention, in a cathode ray tube controller, an index phosphor for detecting geometrical distortion (including convergence) of an image projected by the cathode ray tube is provided on a shadow mask. A cathode ray tube having the same, a detecting means for detecting a two-dimensional position of a scanning electron beam from light or ultraviolet rays emitted from the index phosphor, a geometric distortion correcting circuit for correcting geometric distortion of the cathode ray tube, and the detecting means. 1. A luminance variable detection signal generating circuit for generating a luminance by modulating a test pattern used for detecting the two-dimensional position by using test signal luminance data described later, and 1. 1. Test signal brightness data indicating brightness information at the screen position of the test pattern A memory for storing geometric distortion correction data for correcting the geometric distortion, and when the detecting means detects the two-dimensional position, the luminance variable detection signal generation is performed by the test signal luminance data of the memory. Drive the circuit,
The above problem can be solved by creating geometric distortion correction data of the memory from the result of the detection means detecting the two-dimensional position and driving the geometric distortion correction circuit from the geometric distortion correction data. is there.

According to a second aspect of the present invention, in the cathode ray tube control device, a cathode ray tube having an index phosphor for detecting geometrical distortion (including convergence) of an image projected by the cathode ray tube on a shadow mask, Detecting means for detecting the two-dimensional position of the scanning electron beam from the light or ultraviolet rays emitted from the index phosphor, and a detection signal generating circuit for generating a test pattern used when the detecting means detects the two-dimensional position. A brightness modulation circuit for correcting uniformity of the brightness of the cathode ray tube; and a geometric distortion correction circuit for correcting geometric distortion of the cathode ray tube. Uniformity correction data for uniformity correction of the luminance 2. 2. Test signal brightness data indicating brightness information at the screen position of the test pattern A memory for storing geometric distortion correction data for the geometric distortion correction is provided, and the brightness modulation circuit is normally driven by the uniformity correction data of the memory, but the detection means detects the two-dimensional position. When performing, the brightness modulation circuit is driven by the test signal brightness data of the memory, and the geometric distortion correction data of the memory is created from the result of the detection unit detecting the two-dimensional position. The above problem is solved by driving the geometric distortion correction circuit.

According to a third aspect of the present invention, in the cathode ray tube control device, a cathode ray tube having an index phosphor for detecting a geometric distortion (including convergence) of an image projected by the cathode ray tube on a shadow mask, Detecting means for detecting the two-dimensional position of the scanning electron beam from the light or ultraviolet rays emitted from the index phosphor; a photoelectric conversion circuit for photoelectrically converting the light or ultraviolet rays emitted from the index phosphor by the detecting means; A threshold variable binarization circuit for binarizing the output of the circuit from threshold voltage data described later, and detecting for generating a test pattern used when the detecting means detects the two-dimensional position Signal generation circuit, and a geometric distortion correction circuit for correcting the geometric distortion of the cathode ray tube; 1. Threshold voltage data representing the threshold voltage of the binarization circuit for each screen position. A memory for storing geometric distortion correction data for geometric distortion correction, wherein the threshold variable binarization circuit binarizes the output of the photoelectric conversion circuit from the threshold voltage data, The problem is solved by creating geometric distortion correction data of the memory from the result of the detection means detecting the two-dimensional position and driving the geometric distortion correction circuit from the geometric distortion correction data. .

According to a fourth aspect of the present invention, in the cathode ray tube controller, a cathode ray tube having an index phosphor for detecting a geometric distortion (including convergence) of an image projected by the cathode ray tube on a shadow mask, Detecting means for detecting the two-dimensional position of the scanning electron beam from the light or ultraviolet rays emitted from the index phosphor; a photoelectric conversion circuit for photoelectrically converting the light or ultraviolet rays emitted from the index phosphor by the detecting means; A detection signal generating circuit for generating a test pattern used when the detecting means detects the two-dimensional position; and a geometric distortion of the cathode ray tube. A geometric distortion correction circuit that: 1. Gain data representing the gain of the variable amplifier circuit for each screen position. A memory for storing geometric distortion correction data for correcting the geometric distortion, wherein the variable amplifier circuit amplifies an output of the photoelectric conversion circuit according to the gain data, and the detecting means detects the two-dimensional position. The above problem is solved by creating geometric distortion correction data of the memory based on the result of detection and driving the geometric distortion correction circuit from the geometric distortion correction data.

The invention according to claim 5 is a cathode ray tube having an index phosphor for detecting a geometric distortion (including convergence) of an image projected by the cathode ray tube on a shadow mask, and the index phosphor. Detecting means for detecting the two-dimensional position of the scanning electron beam from the emitted light or ultraviolet ray, a geometric distortion correcting circuit for correcting the geometric distortion of the cathode ray tube, and the detecting means for detecting the two-dimensional position A luminance variable detection signal generation circuit for luminance-modulating a test pattern used for the above-mentioned test signal luminance data to be generated, and 1. 1. Test signal brightness data indicating brightness information at the screen position of the test pattern A memory for storing geometric distortion correction data for correcting the geometric distortion, and when the detecting means detects the two-dimensional position, the luminance variable detection signal generation is performed by the test signal luminance data of the memory. Drive the circuit,
A cathode ray tube control device characterized in that geometric distortion correction data of the memory is created from a result of the detection means detecting the two-dimensional position, and the geometric distortion correction circuit is driven from the geometric distortion correction data. In addition to the detection of the two-dimensional position of the scanning electron beam, the detection means also detects the voltage after photoelectric conversion of light or ultraviolet rays emitted by the index phosphor, and the test signal is detected from the voltage detected by the detection means. The above problem is solved by creating brightness data.

Further, the invention according to claim 6 is a cathode ray tube having an index phosphor for detecting a geometric distortion (including convergence) of an image projected by the cathode ray tube on a shadow mask, and the index phosphor. Detection means for detecting the two-dimensional position of the scanning electron beam from the emitted light or ultraviolet light, a detection signal generation circuit for generating a test pattern used when the detection means detects the two-dimensional position, and the cathode ray tube. A luminance modulation circuit for performing uniformity correction of the luminance of 1., and a geometric distortion correction circuit for correcting geometric distortion of the cathode ray tube; Uniformity correction data for uniformity correction of the luminance 2. 2. Test signal brightness data indicating brightness information at the screen position of the test pattern A memory for storing geometric distortion correction data for the geometric distortion correction is provided, and the brightness modulation circuit is normally driven by the uniformity correction data of the memory, but the detection means detects the two-dimensional position. When performing, the brightness modulation circuit is driven by the test signal brightness data of the memory, and the geometric distortion correction data of the memory is created from the result of the detection unit detecting the two-dimensional position. In the cathode ray tube control device characterized by further driving the geometric distortion correction circuit, the detection means may detect the two-dimensional position of the scanning electron beam,
The above problem is solved by detecting the voltage after photoelectric conversion of light or ultraviolet rays emitted from the index phosphor and creating the test signal brightness data from the voltage detected by the detecting means.

The invention according to claim 7 is a cathode ray tube having an index fluorescent substance on a shadow mask for detecting geometric distortion (including convergence) of an image projected by the cathode ray tube, and the index fluorescent substance. Detection means for detecting the two-dimensional position of the scanning electron beam from the emitted light or ultraviolet rays, a photoelectric conversion circuit for photoelectrically converting the light or ultraviolet rays emitted by the index phosphor, and the output of the photoelectric conversion circuit will be described later. A threshold value variable binarizing circuit for binarizing the threshold voltage data, and a detection signal generating circuit for generating a test pattern used when the detecting means detects the two-dimensional position; A geometric distortion correction circuit for correcting the geometric distortion of the cathode ray tube; 1. Threshold voltage data representing the threshold voltage of the binarization circuit for each screen position. A memory for storing geometric distortion correction data for geometric distortion correction, wherein the threshold variable binarization circuit binarizes the output of the photoelectric conversion circuit from the threshold voltage data, A cathode ray tube control device characterized in that geometric distortion correction data of the memory is created from a result of detection of the two-dimensional position by the detecting means and the geometric distortion correction circuit is driven from the geometric distortion correction data. In addition to the detection of the two-dimensional position of the scanning electron beam, the detection means,
The above problem is solved by detecting the voltage after photoelectric conversion of light or ultraviolet rays emitted from the index phosphor and creating the threshold voltage data from the voltage detected by the detecting means.

The invention according to claim 8 is a cathode ray tube having an index phosphor for detecting geometric distortion (including convergence) of an image projected by the cathode ray tube on a shadow mask, and the index phosphor. Detection means for detecting the two-dimensional position of the scanning electron beam from the emitted light or ultraviolet rays, a photoelectric conversion circuit for photoelectrically converting the light or ultraviolet rays emitted by the index phosphor, and the output of the photoelectric conversion circuit. A detection signal generating circuit for generating a test pattern used when the detecting means detects the two-dimensional position; and a geometric distortion correction for correcting the geometric distortion of the cathode ray tube. Circuit, 1. 1. Gain data representing the gain of the variable amplifier circuit for each screen position. A memory for storing geometric distortion correction data for correcting the geometric distortion, wherein the variable amplifier circuit amplifies an output of the photoelectric conversion circuit according to the gain data, and the detecting means detects the two-dimensional position. In the cathode ray tube control device characterized in that the geometric distortion correction data of the memory is created from the result of the detection and the geometric distortion correction circuit is driven from the geometric distortion correction data, the detecting means is the scanning electron. In addition to detecting the two-dimensional position of the beam, the voltage after photoelectric conversion of light or ultraviolet rays emitted by the index phosphor is also detected, and the gain data is created from the voltage detected by the detecting means. It has been resolved.

[0031]

According to the invention described in claim 1, the brightness information of the test pattern is stored in the memory as the test signal brightness data, and the test is performed while the geometric distortion (including the convergence) of the image is detected. A test pattern having a brightness corresponding to the screen position is generated from the signal brightness data by the brightness variable detection signal generation circuit. As a result of the above, the detecting means stably detects the two-dimensional position of the scanning electron beam at any position on the screen, obtains the geometric correction data from the detection result of the two-dimensional position, stores it in the memory, and stores the geometric correction data. To the geometric correction circuit, and the geometric distortion of the cathode ray tube is corrected.

According to a second aspect of the present invention, the test pattern brightness information is stored in the memory as test signal brightness data according to the above configuration, and the test is performed while geometric distortion (including convergence) of an image is detected. The brightness modulation circuit is driven according to the screen position from the signal brightness data. As a result of the above, the detecting means stably detects the two-dimensional position of the scanning electron beam at any position on the screen, obtains the geometric correction data from the detection result of the two-dimensional position, stores it in the memory, and stores the geometric correction data. To the geometric correction circuit, and the geometric distortion of the cathode ray tube is corrected.

According to a third aspect of the present invention, the threshold data of the variable threshold binarization circuit is stored in the memory according to the above configuration, and the geometric distortion (including convergence) of the image is detected. The output of the amplifier circuit is binarized by a threshold variable binarization circuit using a threshold value according to the screen position. As a result of the above, the detecting means stably detects the two-dimensional position of the scanning electron beam at any position on the screen.
Geometric correction data is obtained from the detection result of the dimensional position, stored in the memory, and output to the geometric correction circuit to correct the geometric distortion of the cathode ray tube.

According to the fourth aspect of the present invention, the gain data of the variable amplifier circuit is stored in the memory by the above configuration, and the output of the photoelectric conversion circuit is output while the geometric distortion (including convergence) of the image is detected. The variable amplification circuit amplifies with a gain according to the screen position. As a result of the above, the detecting means stably detects the two-dimensional position of the scanning electron beam at any position on the screen, obtains the geometric correction data from the detection result of the two-dimensional position, stores it in the memory, and stores the geometric correction data. To the geometric correction circuit, and the geometric distortion of the cathode ray tube is corrected.

According to a fifth aspect of the present invention, the detecting means detects not only the two-dimensional position of the scanning electron beam but also the voltage after photoelectric conversion of light or ultraviolet rays emitted from the index phosphor, Test signal brightness data is created from the voltage detected by the detecting means, and the two-dimensional position of the scanning electron beam is stably detected at any position on the screen using the test signal brightness data. The geometric correction data is obtained from the detection result, stored in the memory, and output to the geometric correction circuit to correct the geometric distortion of the cathode ray tube.

According to a sixth aspect of the present invention, the detecting means detects not only the two-dimensional position of the scanning electron beam but also the voltage after photoelectric conversion of light or ultraviolet rays emitted from the index phosphor, Test signal brightness data is created from the voltage detected by the detection means, the two-dimensional position of the scanning electron beam is stably detected at any position on the screen using the test signal brightness data, and the geometrical shape is obtained from the detection result. The correction data is obtained, stored in the memory, and output to the geometric correction circuit to correct the geometric distortion of the cathode ray tube.

According to a seventh aspect of the present invention, the detecting means detects not only the two-dimensional position of the scanning electron beam but also the voltage after photoelectric conversion of light or ultraviolet rays emitted by the index phosphor, Threshold voltage data is created from the voltage detected by the detection means and binarized by the threshold variable binarization circuit using the threshold data, and the two-dimensional scanning electron beam is stably obtained at any position on the screen. The geometrical position of the cathode ray tube is corrected by detecting the target position, obtaining geometrical correction data from the detection result, storing it in the memory, and outputting it to the geometrical correction circuit.

According to the eighth aspect of the present invention, the detecting means detects not only the two-dimensional position of the scanning electron beam but also the voltage after photoelectric conversion of light or ultraviolet rays emitted from the index phosphor, Gain data is created from the voltage detected by the detection means, the output of the photoelectric conversion circuit is amplified using the gain data with a gain according to the screen position, and a stable scanning electron beam of any position on the screen is obtained. The two-dimensional position is detected, the geometric correction data is obtained from the detection result, stored in the memory, and output to the geometric correction circuit to correct the geometric distortion of the cathode ray tube.

[0039]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A cathode ray tube control device according to an embodiment of the present invention will be described below with reference to the drawings.

(Embodiment 1) FIG. 1 is a block diagram of a cathode ray tube control apparatus according to a first embodiment of the present invention. The same objects and operations as those in FIG. 14 showing a block diagram of a conventional cathode ray tube control device are designated by the same reference numerals, and detailed description thereof will be omitted. In FIG. 1, a portion different from the conventional example is that the data stored in the memory 400 stores the geometric distortion correction data 401 and the test signal luminance data 402 as a two-dimensional array. The difference from the conventional example is that the variable luminance detection signal generation circuit 601 is replaced with the detection signal generation circuit 600.

In the cathode ray tube controller of the first embodiment constructed as described above, the operation itself for correcting the geometric distortion of the cathode ray tube is as described in the conventional example,
The description is omitted because it is known, and the operation unique to the present invention will be described below.

When detecting the geometrical distortion, the switching circuit 700 detects the two-dimensional position of the scanning electron beam, and instead of outputting to the video signal processing circuit 800, the switching circuit 700 outputs a test output from the luminance variable detection signal generating circuit 601. Switch to the pattern signal and display the test pattern on the cathode ray tube.

FIG. 2A shows an arrangement of the index phosphors 3 applied on the shadow mask 2 shown in FIG. 1 when viewed from the phosphor screen 1 side, and an example of a projected test pattern. , Reference numerals 10, 11, 12, 1
Reference numerals 3, 14, and 15 represent test patterns on the index phosphors 3, respectively. For example, in order to detect the two-dimensional position slightly above the left end of the screen, the test pattern is displayed at the position designated by reference numeral 10.

2 (b), 2 (c) and 2 (d), the variable luminance detection signal generating circuit 601 and the amplifying circuits 102, 2 when the variable luminance detection signal generating circuit 601 outputs a test pattern having a constant luminance. The respective output waveforms of the binarization circuit 103 are compared with the test patterns 10, 11, 12, 13, 1
4 and 15 are shown in correspondence with each other. For convenience, the waveforms corresponding to the respective test patterns are synthesized and shown. The vertical axis represents voltage and the horizontal axis represents time. Reference numerals 42a, 4
Waveforms with 4a and 45a are described by dotted lines,
The above-mentioned waveform is in the vicinity of the threshold voltage and represents the state in which the output waveform appears or does not appear in the binarization circuit 103 each time it is detected. Reference numeral 45 indicates that originally two output waveforms appear, but since the output waveform of the amplifier circuit 102 is below the threshold voltage, it is not normally binarized.

FIG. 2 shows how the above binarization is normally performed.
The test signal brightness data 402 is created in advance so that the brightness of the test pattern at the position corresponding to the low voltage of the output waveform in (c) is increased, and the brightness of the test pattern is decreased at the high voltage of the output waveform. It will be good if you keep it.

As described above, the test signal brightness data 402
Output waveforms of the variable luminance detection signal generation circuit 601, the amplification circuit 102, and the binarization circuit 103 when the above are created are shown in FIGS. As can be seen from the figure, binarization is normally performed and detection is stable.

As described above, according to this embodiment, the test pattern brightness data 402 is output from the amplification circuit 102 in the detection circuit 100 in advance where the voltage output from the amplifier circuit 102 is low, and when the voltage is high the test pattern is tested. By setting the brightness of the pattern to be weak, it is possible to stably detect the two-dimensional position of the scanning electron beam at any position on the screen.

Incidentally, the detection signal generating circuit 600 of the conventional example.
Generates a test pattern by switching the reference voltage at a predetermined timing. However, the luminance variable detection signal generating circuit 601 is formed only by replacing the reference voltage with the waveform generated from the test signal luminance data 402 of this embodiment. It is possible to obtain the above configuration relatively easily.

(Embodiment 2) FIG. 3 is a block diagram of a cathode ray tube control apparatus according to a second embodiment of the present invention. It should be noted that the same objects and operations as those in FIG. 14 showing the block diagram of the conventional cathode ray tube control device are designated by the same reference numerals, and detailed description thereof will be omitted. In FIG. 3, reference numeral 500 denotes a brightness modulation circuit that modulates the brightness of a video signal to be displayed on the cathode ray tube according to the supplied modulation data, and performs uniformity correction of the brightness of the cathode ray tube described in the conventional example. It is similar. Also, 4
00 is a memory for storing the geometric distortion correction data 401, the test signal brightness data 402 and the uniformity correction data 403 as a two-dimensional array according to the position of the image projected by the cathode ray tube, and 701 is the test signal brightness data or the uniformity correction data. Either of them is given to the brightness modulation circuit 500 as modulation data, and in conjunction with the above, either the test pattern generated by the detection signal generation circuit 600 or the output of the video signal processing circuit 800 is supplied to the brightness modulation circuit 500 as a video signal. Is a switching circuit that outputs as.

In the cathode ray tube controller of the first embodiment constructed as described above, the test signal brightness data 402 is stored in the memory 400, which is different from the structure of the conventional example in which the brightness modulation circuit is added. And switching circuit 7
The function of 01 is expanded as compared with the switching circuit 700 of the conventional example.

The video signal processed by the video signal processing circuit 800 is corrected on the uniformity of the brightness of the cathode ray tube by the brightness modulation circuit 500 and is displayed on the cathode ray tube. Uniformity correction data 4 stored in 400
03 is applied to the luminance modulation circuit 500 by controlling the switching circuit 701, and at the same time, the switching circuit 701 controls the video signal processing circuit 800.
It is obtained by outputting the video signal output by the above to the luminance modulation circuit 500 as a modulated signal. The above operation is a known operation used for uniformity correction of the brightness of a cathode ray tube that is normally used, and there is no inventive step in the above points.

However, in order to detect the two-dimensional position of the scanning electron beam when detecting the geometric distortion of the cathode ray tube, the switching circuit 701 is provided in the detection signal generating circuit 600 instead of the output of the video signal processing circuit. The test pattern signal to be output is switched and given to the luminance modulation circuit 500. On the other hand, the switching circuit 700 simultaneously takes out the test signal brightness data 402 instead of the uniformity correction data 403 stored in the memory 400 and supplies it to the brightness modulation circuit 500 as modulation data.

The above operation is the same as that of the luminance variable detection signal generation circuit 601 of FIG. 1 described in the first embodiment, resulting in the same effect as that of the first embodiment.

The arithmetic / control circuit 200 and the memory 40
If 0 is realized in combination with software by using a microcomputer circuit that is currently generally used, the switching circuit 70
1 and the data stored in the memory 400 can be realized by software. Therefore, in practice, the configuration of the conventional example in which the luminance modulation circuit 500 is added can be realized by changing only the software, and the practical effect in terms of cost becomes large.

(Embodiment 3) FIG. 4 is a block diagram of a cathode ray tube controller in a third embodiment of the present invention. It should be noted that the same objects and operations as those in FIG. 14 showing the block diagram of the conventional cathode ray tube control device are designated by the same reference numerals, and detailed description thereof will be omitted. In FIG. 4, 106 in the detection means 100 corresponds to the binarization circuit 103 in the conventional example, and the threshold voltage at the time of binarization is made variable by receiving threshold voltage data 404 described later. It is a variable threshold binarizing circuit. Also, memory 4
In addition to the geometric distortion correction data 401 which is also present in the conventional example, 00 stores threshold voltage data 403 given to the variable threshold binarization circuit 106 as a two-dimensional array.

In the cathode ray tube control apparatus of the third embodiment having the above-described configuration, the operation itself for correcting the geometric distortion of the cathode ray tube having the above-described configuration is as described in the conventional example, and is a known one. I will omit the explanation,
The operation unique to the present invention will be described below.

When detecting the geometric distortion, a test pattern is projected on the cathode ray tube as in the other embodiments.

Similar to FIG. 2A, FIG. 5A shows an arrangement state of the index phosphors 3 in the shadow mask 2 and an example of a projected test pattern.

5 (b), 5 (c) and 5 (d), the detection signal generation circuit 600, the amplification circuit 102, and the threshold variable type binarization when the detection signal generation circuit 600 outputs a test pattern. The respective output waveforms when the circuit 106 keeps the threshold value constant are shown as in FIGS. 2B, 2C and 2D. It can be understood from FIG. 5D that the binarization is not normally performed as in the first embodiment.

Therefore, in order to normally perform the binarization, the threshold voltage data 404 is set so that the threshold value becomes low in the low voltage portion based on the detection signal in FIG. ,
The high voltage portion may be made in advance so that the threshold value becomes high.

Output waveforms of the detection signal generation circuit 600, the amplification circuit 102, and the threshold variable type binarization circuit 106 when using the above data are shown in FIGS.
It shows in (g). As can be seen from the figure, binarization is normally performed and detection is stable.

As described above, according to this embodiment, the threshold voltage data 402 created based on the strength of the detection level depending on the location is stored in the memory 400, and the threshold variable type 2 is stored according to the data. By changing the threshold voltage of the digitizing circuit 106, the two-dimensional position of the scanning electron beam can be stably detected at any point on the screen.

(Embodiment 4) FIG. 6 is a block diagram of a cathode ray tube controller in a fourth embodiment of the present invention. It should be noted that the same objects and operations as those in FIG. 14 showing the block diagram of the conventional cathode ray tube control device are designated by the same reference numerals, and detailed description thereof will be omitted. In FIG. 6, 107 in the detecting means 100 corresponds to the amplifier circuit 102 in the conventional example, and is a variable amplifier circuit that makes the gain at the time of amplification variable by receiving gain data 405 described later. Further, the memory 400 stores gain data 405 to be given to the variable amplification circuit 107 as a two-dimensional array in addition to the geometric distortion correction data 401 also in the conventional example.

In the cathode ray tube control apparatus according to the fourth embodiment having the above-described configuration, the operation itself for correcting the geometric distortion of the cathode ray tube having the above-described configuration is as described in the conventional example, and is well known. I will omit the explanation,
The operation unique to the present invention will be described below.

When detecting the geometric distortion, a test pattern is projected on the cathode ray tube as in the other embodiments.

Similar to FIG. 2A, FIG. 7A shows an arrangement state of the index phosphors 3 in the shadow mask 2 and an example of a projected test pattern.

FIGS. 7B, 7C and 7D show when the detection signal generation circuit 600 and the variable amplification circuit 107 have constant gains when the detection signal generation circuit 600 outputs a test pattern. The respective output waveforms of the binarization circuit 103 are shown as in FIGS. 2B, 2C, and 2D. Figure 7
It can be seen from (d) that the binarization is not normally performed as in the first embodiment.

Therefore, in order to normally perform the binarization, the gain data 405 is set so that the gain of the variable amplifier circuit 107 becomes large in the low voltage portion based on the detection signal in FIG. The high voltage portion may be made in advance so that the gain of the variable amplifier circuit 107 becomes small.

Output waveforms of the detection signal generation circuit 600, the variable amplification circuit 107, and the binarization circuit 103 when using the above data are shown in FIGS. 7 (e), (f), and (g), respectively. As can be seen from the figure, binarization is normally performed and detection is stable.

As described above, according to this embodiment, the gain data 405 created based on the strength of the detection level depending on the location is stored in the memory 400, and the gain of the variable amplification circuit 107 is changed by the data. The two-dimensional position of the scanning electron beam can be stably detected at any point on the screen.

(Embodiment 5) FIG. 8 shows a block diagram of a cathode ray tube controller in a fifth embodiment of the present invention. The same objects and operations as those in FIG. 1 showing the block diagram of the cathode ray tube control apparatus of the first embodiment are designated by the same reference numerals, and detailed description thereof will be omitted. Figure 8
In the detection means 100, 110 is a peak detection circuit for peak detection of the voltage output from the amplification circuit circuit 102, and 111 is the output of the peak detection circuit 110 and T-V.
It is a switching circuit which receives the output of the conversion circuit 104 as an input and outputs one of the inputs to the A / D conversion circuit 105 according to a control signal from an arithmetic / control circuit 201 described later. Further, 201 is the arithmetic / control circuit 2 in the first embodiment.
00, in addition to the function of 00, a function of generating a control signal for controlling the switching circuit 111 and a function of calculating and obtaining the test signal brightness data 402.

When the operation of the first embodiment is performed in FIG. 8, the arithmetic / control circuit 201 causes the switching circuit 111 to select the output of the TV conversion circuit 104 and input it to the A / D conversion circuit 105. In the above case, the effects of the first embodiment can be obtained as described in the first embodiment.

On the other hand, when creating the test signal luminance data 402, the arithmetic / control circuit 201 causes the switching circuit 111 to select the output of the peak detection circuit 110.
Input to 05.

FIG. 9 shows a waveform diagram of the peak detection circuit 110.
The operation of will be described. FIG. 9A shows the index phosphor 3
Is a view when viewed from the phosphor screen 1 side, and 10 is a projected test pattern. Light or ultraviolet rays are generated by hitting the index phosphor 3 with the test pattern, converted into an electric signal by the photoelectric conversion circuit 101 and passed through the amplifier circuit 102, and then a detection signal as shown in FIG. 9B is obtained. The detection signal is input to the peak detection circuit 110. Fig. 10 shows the principle of a typical peak detection circuit.
It is used to explain the operation of the peak detection circuit 110. In FIG. 10, 1101 is an input terminal of the peak detection circuit, 1106.
Is an output terminal. 1102 is a detection diode, 11
Reference numeral 03 is a capacitor, 1104 is a load resistor that determines a time constant, 1105 is an output buffer, 1107 is a capacitor 1
A switch for discharging 103.

The detection signal of FIG. 9 (b) that has entered the input terminal 1101 is passed through the diode 1102 and
Charged to 3. It is assumed that the capacitor 1103 is charged from the fully discharged state. In FIG. 9B, when the voltage of the detection signal indicated by A exceeds the peak, the diode 1102 is turned off and the diode 1102 is discharged with a time constant determined by the load resistor 1104 and the capacitor 1103.
Usually, the load resistance 1104 is made large so as not to be easily discharged. Next, in FIG. 9B, the peak of the second detection signal shown by B occurs, and when the charging voltage of the capacitor 1103 is exceeded, the diode 1102 is turned on again and the capacitor 1103 is charged, and shown by C in FIG. 9B. At that time, the diode 1102 is turned off again and the peak voltage of the detection signal is held. The peak voltage is output from the output terminal 1106 through the buffer 1105.

Before and after the explanation, the switch 1107 has already been closed just before the peak detection operation described above, and the capacitor 1103 has been sufficiently discharged. During the peak detection operation period, the switch 1107 is controlled to remain open, and the capacitor 1104 is discharged only through the load resistor 1104. As a result of the above operation, the output terminal 1106 is shown in FIG.
A voltage waveform as shown in (c) is obtained.

As described above, the voltage after peak detection is A / D
The data is converted and taken into the arithmetic / control circuit 201 as data. The arithmetic / control circuit 201 creates the test signal brightness data 402 so that the data becomes constant at any position on the screen and is equal to or higher than the threshold voltage of the binarization circuit 103. There are various publicly known methods for actual data creation, and any known or unknown procedure may be used.

As described above, in this embodiment, the peak detection circuit 110 and the switching circuit 111 are provided in the detection means 100, and the voltage after the photoelectric conversion of the light or the ultraviolet rays emitted from the index phosphor 3 is detected to detect the test signal. It is possible to automatically create the brightness data 402.

Further, in the first embodiment, the test signal brightness data 402 had to be created in advance, so the detection was stable due to factors such as the sagging of the index phosphor 3 and the aging of the electron gun of the cathode ray tube. There was a problem that it will not be done.

Further, in the first embodiment, creating the test signal brightness data 402 in advance has a problem that the time and effort required for shipment adjustment at a factory or the like increases.

However, in the present embodiment, the above problem can be solved by automatically generating the test signal brightness data 402 before detecting the two-dimensional position of the scanning electron beam of the cathode ray tube.

(Embodiment 6) FIG. 11 is a block diagram of a cathode ray tube controller in a sixth embodiment of the present invention. The same objects and operations as those in FIG. 3 showing the block diagram of the cathode ray tube control device of the second embodiment are designated by the same reference numerals, and detailed description thereof will be omitted. In FIG. 11, the peak detection circuit 11 in the detection means 100 is shown.
0, the switching circuit 111 is the same as that of the fifth embodiment.
The arithmetic / control circuit 201 is the same as that of the fifth embodiment.

Therefore, the test signal brightness data 402 can be created exactly as in the case of the fifth embodiment, and the same effect can be obtained.

(Embodiment 7) FIG. 12 is a block diagram of a cathode ray tube controller in a seventh embodiment of the present invention. The same objects and operations as those in FIG. 4 showing the block diagram of the cathode ray tube control apparatus of the third embodiment are designated by the same reference numerals, and detailed description thereof will be omitted. In FIG. 12, the peak detection circuit 11 in the detection means 100 is shown.
0, the switching circuit 111 is the same as that of the fifth embodiment.
Further, 202 is the arithmetic / control circuit 200 of the third embodiment.
In addition to the above function, the calculation / control circuit has a function of generating a control signal for controlling the switching circuit 111 and a function of calculating and obtaining the threshold voltage data 404.

In the case of performing the operation of the third embodiment in FIG. 12, the arithmetic / control circuit 202 causes the switching circuit 111 to perform TV conversion.
The output of the conversion circuit 104 is selected and the A / D conversion circuit 105 is selected.
To enter. In the above case, the effect of the third embodiment can be obtained as described in the third embodiment.

On the other hand, when the threshold voltage data 404 is created, the arithmetic / control circuit 202 causes the switching circuit 111 to select the output of the peak detection circuit 110.
Input in 5. The operation of the peak detection circuit 110 is similar to that of the fifth embodiment, and its explanation is omitted.

The voltage after peak detection is A / D converted and taken into the arithmetic / control circuit 201 as data. Calculation·
Since the data is also the input voltage of the threshold voltage variable binarization circuit 106, the control circuit 202 outputs, for example, a value of ⅔ of the data and the like to the threshold voltage variable binarization circuit 10.
The threshold voltage data 404 is created so that the threshold value becomes 6.

As described above, in this embodiment, the threshold is detected by providing the peak detection circuit 110 and the switching circuit 111 in the detection means 100 and detecting the voltage after photoelectric conversion of light or ultraviolet rays emitted from the index phosphor 3. The value voltage data 404 can be automatically created.

Further, in the third embodiment, the threshold voltage data 404 had to be created in advance, so that it could be detected due to factors such as the sagging of the index phosphor 3 and the aging of the electron gun of the cathode ray tube. There was a problem that it could not be performed stably.

In addition, in the third embodiment, creating the threshold voltage data 404 in advance has a problem that the time and effort required for shipment adjustment at a factory or the like increases.

However, in the present embodiment, the above problem can be solved by automatically creating the threshold voltage data 404 before detecting the two-dimensional position of the scanning electron beam of the cathode ray tube.

(Embodiment 8) FIG. 13 is a block diagram of a cathode ray tube controller in an eighth embodiment of the present invention. The same objects and operations as those in FIG. 6 showing the block diagram of the cathode ray tube control device of the fourth embodiment are designated by the same reference numerals, and detailed description thereof will be omitted. In FIG. 13, the peak detection circuit 11 in the detection means 100 is shown.
0, the switching circuit 111 is the same as that of the fifth embodiment.
Reference numeral 203 denotes the arithmetic / control circuit 200 of the fourth embodiment.
In addition to the above function, the arithmetic / control circuit has a function of generating a control signal for controlling the switching circuit 111 and a function of calculating and obtaining the gain data 405.

In the case of performing the operation of the fourth embodiment in FIG. 13, the arithmetic / control circuit 203 causes the switching circuit 111 to perform TV conversion.
The output of the conversion circuit 104 is selected and the A / D conversion circuit 105 is selected.
To enter. In the above case, the effect of the fourth embodiment can be obtained in the same manner as described in the fourth embodiment.

On the other hand, when the gain data 405 is created,
The arithmetic / control circuit 203 causes the switching circuit 111 to select the output of the peak detection circuit 110 and input it to the A / D conversion circuit 105. The operation of the peak detection circuit 110 is similar to that of the fifth embodiment, and its explanation is omitted.

The voltage after peak detection is A / D converted and taken into the arithmetic / control circuit 203 as data. Calculation·
The control circuit 203 creates gain data 405 so that the data becomes constant at any position on the screen and is equal to or higher than the threshold voltage of the binarization circuit 103. There are various publicly known methods for actual data creation, and any known or unknown procedure may be used.

As described above, in this embodiment, the peak detection circuit 110 and the switching circuit 111 are provided in the detection means 100, and the voltage after the photoelectric conversion of the light or ultraviolet rays emitted from the index phosphor 3 is detected to obtain the gain data. 405 can be automatically created.

In addition, in the fourth embodiment, the gain data 4
Since No. 05 had to be prepared in advance, there was a problem that detection could not be performed stably due to factors such as the fatigue of the index phosphor 3 and the aging of the electron gun of the cathode ray tube.

In addition, in the fourth embodiment, the gain data 4
There is a problem in that the preparation of 05 in advance increases the time and effort for shipment adjustment at factories and the like.

However, in the present embodiment, the above problem can be solved by automatically creating the gain data 404 before detecting the two-dimensional position of the scanning electron beam of the cathode ray tube.

[0100]

As described above, according to the present invention, it is possible to provide a cathode ray tube control device for detecting a stable two-dimensional position of an electron beam anywhere in a region where a cathode ray tube is projected. It is possible to provide a cathode ray tube control device capable of detecting a stable two-dimensional position of an electron beam anywhere in the region where the cathode ray tube is projected without increasing the number of detectors, and its practical effect is great.

[Brief description of drawings]

FIG. 1 is a block configuration diagram of a cathode ray tube control device according to a first embodiment of the present invention.

FIG. 2 is an operation waveform diagram of the embodiment.

FIG. 3 is a block configuration diagram of a cathode ray tube control device according to a second embodiment of the present invention.

FIG. 4 is a block configuration diagram of a cathode ray tube control device according to a third embodiment of the present invention.

FIG. 5 is an operation waveform diagram of the embodiment.

FIG. 6 is a block configuration diagram of a cathode ray tube control device according to a fourth embodiment of the present invention.

FIG. 7 is an operation waveform diagram of the embodiment.

FIG. 8 is a block configuration diagram of a cathode ray tube control device according to a fifth embodiment of the present invention.

FIG. 9 is a waveform diagram of the detection means in the embodiment.

FIG. 10 is a circuit diagram of a typical peak detection circuit.

FIG. 11 is a block configuration diagram of a cathode ray tube control device according to a sixth embodiment of the present invention.

FIG. 12 is a block configuration diagram of a cathode ray tube control device according to a seventh embodiment of the present invention.

FIG. 13 is a block configuration diagram of a cathode ray tube controller according to an eighth embodiment of the present invention.

FIG. 14 is a block configuration diagram of a conventional cathode ray tube control device.

FIG. 15 is an operation waveform diagram of the same embodiment.

[Explanation of symbols]

1 phosphor screen 2 shadow mask 3 index phosphor 4 deflection / convergence yokes 10, 11, 12, 13, 14, 15 test patterns 20, 21, 22, 23, 24, 25 test pattern signals 30, 31, 32, 33, 34, 35 Detection signal 39 Threshold voltage 40, 41, 42, 43, 44, 45 Detection pulse signal 50, 51, 52, 53, 54, 55 Modulated test pattern signal 60, 61, 62, 63, 64 , 65 detection signals 70, 71, 72, 73, 74, 75 detection pulse signal 100 detection means 101 photoelectric conversion circuit 102 amplification circuit 103 binarization circuit 104 TV conversion circuit 105 A / D conversion circuit 106 threshold voltage Variable type binarization circuit 107 Variable amplification circuit 110 Peak detection circuit 111 Switching circuit 200 in detection means Operation / control circuit 01 Arithmetic / Control Circuit 202 in Fifth and Sixth Embodiments Arithmetic / Control Circuit 203 in Seventh Embodiment Arithmetic / Control Circuit 300 in Eighth Embodiment Geometrical Distortion Correction Circuit 400 Memory 401 Geometrical Distortion Correction Data 402 test signal brightness data 403 uniformity correction data 404 threshold value data 405 gain data 500 brightness modulation circuit 600 detection signal generation circuit 601 brightness variable detection signal generation circuit 700 switching circuit 701 switching circuit 800 in the second embodiment video signal Processing circuit 1101 Input terminal 1102 in typical peak detection circuit Diode 1103 in typical peak detection circuit Capacitor 1104 in typical peak detection circuit Load resistance 1105 in typical peak detection circuit Output buffer 110 in typical peak detection circuit 6 Output terminal 1107 in typical peak detection circuit Switch in typical peak detection circuit

─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-4-172095 (JP, A) JP-A-5-145935 (JP, A) JP-A-5-236485 (JP, A) JP-A-6- 121178 (JP, A) (58) Fields surveyed (Int.Cl. ⁷ , DB name) H04N 9/24 G09G 1/00

Claims (4)

(57) [Claims] 1. A cathode ray tube provided with an index phosphor in a shadow mask, a detection means for detecting a two-dimensional position of a scanning electron beam from the index phosphor, and a geometry for correcting geometric distortion of the cathode ray tube. A distortion correction circuit, a luminance variable detection signal generating circuit for luminance-modulating a test pattern used when the detecting unit detects the two-dimensional position by test signal luminance data described later, and a screen position of the test pattern. And a memory for storing the geometric distortion correction data for the geometric distortion correction, the test of the memory when the detecting means detects the two-dimensional position. The brightness variable detection signal generating circuit is driven by signal brightness data, and the detection means detects the two-dimensional position, A cathode ray tube control device characterized in that geometric distortion correction data of a memory is created and the geometric distortion correction circuit is driven from the geometric distortion correction data. 2. A cathode ray tube provided with a shadow mask of an index phosphor, a detecting means for detecting a two-dimensional position of a scanning electron beam from the index phosphor, and the detecting means for detecting the two-dimensional position. uniformity for the detection signal generation circuit for generating a test pattern for use in a brightness modulation circuit for the uniformity correction of the luminance of the cathode ray tube, uniformity correction of the luminance
Correction data and geometric distortion correction data for geometric distortion correction
And a geometric distortion correction circuit for correcting the geometric distortion of the cathode ray tube.
A cathode ray tube control device including, showing the brightness information at the screen position of the test pattern
And a second memory for storing the brightness data of the test signal
For example, normally to drive the intensity modulator from the uniformity correction data of said first memory, said when said detecting means to detect the two-dimensional position
The test signal brightness data of the second memory drives the brightness modulation circuit so that the detection is normally performed, and the detection means detects the two-dimensional position, and the geometry of the first memory is obtained. A cathode ray tube control device characterized in that distortion correction data is created and the geometric distortion correction circuit is driven from the geometric distortion correction data. 3. A cathode ray tube provided with an index phosphor in a shadow mask, a detecting means for detecting a two-dimensional position of a scanning electron beam from the index phosphor, and a geometry for correcting geometric distortion of the cathode ray tube. A distortion correction circuit, a luminance variable detection signal generating circuit for luminance-modulating a test pattern used when the detecting unit detects the two-dimensional position with test signal luminance data described later, and a screen position of the test pattern. And a memory for storing the geometric distortion correction data for the geometric distortion correction, the test of the memory when the detecting means detects the two-dimensional position. The brightness variable detection signal generating circuit is driven by signal brightness data, and the detection means detects the two-dimensional position, In a cathode ray tube control device characterized in that geometric distortion correction data of memory is created, and the geometric distortion correction circuit is driven from the geometric distortion correction data, the detecting means detects the two-dimensional position of the scanning electron beam. In addition to the above, the cathode ray tube control device is characterized in that a voltage after photoelectric conversion of light or ultraviolet rays emitted from the index phosphor is also detected, and the test signal brightness data is created from the voltage detected by the detection means. 4. A cathode ray tube provided with an index phosphor in a shadow mask, detection means for detecting a two-dimensional position of a scanning electron beam from light or ultraviolet rays emitted from the index phosphor, and the detection means is the index fluorescence. The detection means includes: a photoelectric conversion circuit that photoelectrically converts light or ultraviolet rays emitted from the body; and a threshold variable binarization circuit that binarizes the output of the photoelectric conversion circuit from threshold voltage data described below. A detection signal generating circuit for generating a test pattern used when detecting the two-dimensional position, a geometric distortion correction circuit for correcting geometric distortion of the cathode ray tube, and a threshold value of the binarization circuit. Threshold voltage data representing a voltage for each screen position and a memory for storing the geometric distortion correction data for the geometric distortion correction; The digitizing circuit binarizes the output of the photoelectric conversion circuit from the threshold voltage data, and creates geometric distortion correction data of the memory from the result of the detection of the two-dimensional position by the detecting means to generate geometric distortion. In the cathode ray tube control device characterized by driving the geometric distortion correction circuit based on the correction data, the detecting means detects the two-dimensional position of the scanning electron beam, and detects the light or ultraviolet rays emitted from the index phosphor. A cathode ray tube control device characterized in that the voltage after photoelectric conversion is also detected, and the threshold voltage data is created from the voltage detected by the detecting means.