KR20030096902A - apparatus and method for compensating auto-convergence of projection TV - Google Patents

Abstract

PURPOSE: An apparatus and a method for automatically compensating convergence of a projection TV are provided to accurately and precisely compensate a convergence error by compensating the convergence error with moving photo sensors. CONSTITUTION: A convergent compensation value is initialized. If an error of the convergence is generated, a digital convergence control unit(15) selects alignment patterns of red, green, and blue, and displays the selected alignment pattern on a display(12). The convergence error is detected by measuring distances from the alignment patterns to photo sensors(11), and the convergence error is stored in a memory. The digital convergence control unit compensates the convergence error through an RGB projecting part, and selects the accuracy of the convergence compensation. A system control unit(14) calculates moving distances of the photo sensors according to the selected accuracy, and drives a motor. The motor moves a transfer device, and the photo sensors slowly move following a guide line by the transfer device.

Description

Apparatus and method for compensating auto-convergence of projection TV}

The present invention relates to a projection TV, and more particularly, to an apparatus and method for automatic convergence correction of a projection TV.

In general, a projection TV includes red, green, and blue projection tubes, and enlarges an image by displaying an image projected therefrom through an optical unit including a plurality of reflectors, lenses, and the like, on a large screen.

However, since each projection tube is arranged in a straight line with respect to the screen, the image projected from each projection tube does not exactly match on the screen, and thus there is a problem that the sharpness of the screen is reduced.

Therefore, in order to solve this problem, the projection TV is essentially provided with a convergence correction device that adjusts the image projected from each projection tube to exactly match the screen.

In general, a projection TV is factory-converged at the factory. Convergence-corrected projection TVs are used in ordinary homes to generate convergence errors due to environmental changes and surrounding magnetic fields.

Therefore, at home, a convergence correction device can be used to correct the error of convergence.

Existing convergence correction apparatus, as shown in Figure 1, arranges eight optical sensors on the back of the screen, detects the error degree of convergence through the optical sensors, and then corrects the convergence by the detected error.

That is, the conventional convergence correction device places the optical sensor around the screen, measures the distance between the alignment pattern in the vertical and horizontal directions and the optical sensor, corrects the error of convergence, and stores the correction data in the memory. .

If the error of convergence occurs again due to environmental change or the surrounding geomagnetic field, the user corrects the convergence by using the difference between the error degree of the convergence and the correction data stored in the memory.

However, the conventional convergence correction device has a disadvantage in that the manufacturing cost increases due to the large number of optical sensors arranged around the screen, and thus there is a limit to precisely correct the error of the convergence.

In addition, since the user cannot arbitrarily adjust the convergence device, there is a disadvantage in that a more precise convergence correction cannot be performed.

SUMMARY OF THE INVENTION The present invention has been made to solve these problems, and an object of the present invention is to provide an apparatus and method for automatic convergence correction of a projection TV that can accurately correct the error of convergence even with a small number of optical sensors.

Another object of the present invention is to provide an apparatus and method for automatic convergence correction of a projection TV, which enables a user to arbitrarily adjust the correction accuracy of convergence.

Another object of the present invention is to provide an apparatus and method for automatic convergence correction of a projection TV that can lower the cost of a product.

1 is a view schematically showing a convergence correction device of a projection TV according to the prior art

2 is a block diagram schematically showing an automatic convergence correction apparatus of a projection TV according to the present invention.

3 is a view for explaining a convergence correction method according to the present invention.

4 is a flowchart showing a method for correcting convergence according to the present invention.

Explanation of symbols for main parts of the drawings

11 light sensor 12 display unit

13 sensor interface 14 system control

15 digital convergence control unit 16 driving unit

17: moving guide line portion

An automatic convergence correction apparatus of a projection TV according to the present invention includes a display unit for displaying an applied image signal, a movement guide unit disposed along the periphery of the display unit, at least one optical sensor moving along the movement guide unit, and an optical sensor A driving unit for moving the control unit, a system control unit which controls the driving unit, detects an error value of convergence from an output signal of the optical sensor, and outputs a control signal according thereto, and an error of the convergence displayed on the display unit according to the control signal of the system control unit. It consists of a digital convergence control unit for correction.

Here, the movement guide portion is disposed on the back side of the display unit or is spaced apart from the back side of the display unit by a predetermined distance.

In addition, the light sensor is composed of four and located at four corners of the moving guide portion, and each optical sensor moves in a straight line along the moving guide portion.

The driving unit includes a transfer unit for moving the optical sensor and a motor unit for driving the transfer unit in accordance with a control signal of the system control unit.

Here, the transfer part is made of any one of a wire, a chain, a rail and a rubber belt, and the motor part is made of a step motor.

The automatic convergence correction method of the projection TV according to the present invention includes the steps of initializing the convergence, displaying the alignment pattern on the display unit, and detecting and storing an error value of the convergence by measuring the distance between the optical sensor and the alignment pattern. Determining whether to detect the error of convergence more precisely; and if the determination result does not detect the error of convergence further, correcting the error of convergence according to the error value of the stored convergence, and detecting the error of convergence more precisely. If so, selecting the correction accuracy of convergence, moving the optical sensor according to the selected correction precision, and detecting and storing the error value of the convergence by measuring the distance between the moved optical sensor and the alignment pattern. It consists of steps.

Herein, the moving of the optical sensor includes determining a moving distance of the optical sensor according to the selected correction precision, and moving the optical sensor by the determined distance.

The convergence correction method of the present invention comprises the steps of: initializing the convergence, selecting an alignment pattern of one of red, green, and blue, displaying the selected alignment pattern on a display, and determining a distance between the alignment pattern and the optical sensor. Detecting and storing the error value of the convergence; determining whether all the error values of the convergence of the red, green, and blue alignment patterns have been detected; and if all of the determination results are detected, whether the error of the convergence is further detected. And determining the correction error of the convergence according to the stored error value of the convergence if no error of convergence is detected, and selecting the correction accuracy of the convergence if the error of the convergence is further detected. Moving the light sensor along the way, red, green, Selecting an alignment pattern of one color of blue and repeatedly displaying the selected alignment pattern on a display unit.

Here, if all the error values of the convergence of the red, green, and blue alignment patterns are not detected, repeating the steps of selecting an alignment pattern of any one of red, green, and blue and displaying the selected alignment pattern on the display unit. do.

The moving of the optical sensor may include determining a moving distance of the optical sensor according to the selected correction precision, and moving the optical sensor by the determined distance.

The present invention according to such a configuration and method can accurately and accurately correct errors of convergence even with a small number of detection sensors, and can lower the unit cost of a product.

In addition, the error of convergence can be corrected with a precision desired by the user.

Other objects, features and advantages of the present invention will become apparent from the following detailed description of embodiments taken in conjunction with the accompanying drawings.

Referring to the accompanying drawings, preferred embodiments of the present invention having the features as described above are as follows.

First, the concept of the present invention allows the optical sensor to be moved along a guideline, so that the error of convergence can be corrected accurately and accurately even with a small number of optical sensors, as well as to correct the error of convergence with a desired precision. It is.

2 is a block diagram schematically illustrating an automatic convergence correction apparatus of a projection TV according to the present invention.

As shown in FIG. 2, the present invention provides a system controller 14 having a display unit 12, an optical sensor 11, a sensor interface unit 13, an EPROM, a microcomputer, and a memory. And a digital convergence control unit 15 including a drive unit 16 and an RGB projection unit.

Here, the movement guide unit 17 is disposed at the periphery of the display unit 12, and the movement guide unit 17 is disposed on the rear side of the display unit 12 or spaced apart from the rear side of the display unit 12 by a predetermined distance. It may be arranged.

That is, the movement guide unit 17 disposed at the periphery of the display unit 12 is located on the rear side of the overscan area of the display unit 12.

However, if there is no space left around the back of the display 12, it may be disposed at a distance away from the back of the display 12.

However, the moving distance should be within a range in which the amount of light irradiated to the optical sensor 11 moving along the movement guide unit 17 does not change significantly compared to the rear surface of the display unit 12.

In addition, the light sensor 11 is composed of four, each located at four corners of the movement guide portion 17, each optical sensor 11 is moved in a straight line along the movement guide portion (17).

In some cases, only one to three optical sensors 11 may be manufactured.

If only one optical sensor 11 is used, one optical sensor 11 needs to correct the error of convergence while moving around the display unit 12. It may be a bit slower than correcting the error.

However, since only one optical sensor 11 is used, the configuration of the circuit is simple, which has the advantage of lowering the price of the product.

In addition, the sensor interface 13 is connected to the optical sensors 11 in a wired OR form in order to output a signal sensed by the optical sensor 11.

In some cases, one sensor interface unit 13 may be connected in series to one optical sensor 11 to increase the processing speed, but each optical sensor 11 may be connected to one sensor interface unit 13. The parallel connection has the advantage of simplifying the circuit configuration.

In addition, the drive unit 16 includes a transfer device for moving the optical sensor 11 and a motor for driving the transfer device in accordance with a control signal of the system control unit 14.

Here, the transfer apparatus may use a wire, a chain, a rail, a rubber belt, and the like, and the motor may use a stepper motor for precise and accurate movement of the optical sensor.

The optical sensor 11 of the present invention uses an amorphous solar cell having a large light detection area, but other types of sensors can be used.

The convergence correction method of the present invention configured as described above is as follows.

3 is a conceptual diagram illustrating an automatic convergence correction method of a projection TV according to the present invention.

In general, a projection TV is factory-converged at the factory. Convergence-corrected projection TVs are used in ordinary homes to generate convergence errors due to environmental changes and surrounding magnetic fields.

Therefore, in order to correct the error of convergence, it is necessary to know how much the convergence has changed than the initially corrected convergence.

As shown in FIG. 3, if the position of convergence already corrected at the factory is P1 and the position of convergence where an error occurs in a general assumption is P2, the convergence should be corrected from position P2 to position P1 in order to correct the error of convergence. something to do.

Therefore, in order to obtain the vector c, which is the distance and direction in which the convergence should be corrected, the vector a between the optical sensor and P1 and the vector b between the optical sensor and P2 must be obtained first using the position of the optical sensor as a reference point.

The vector a is stored in the memory as a factory-defined value, and the vector c can be easily obtained by finding the vector b using the alignment pattern.

To know the vector b, we first need to know the position of the optical sensor that is the reference point.

Therefore, the alignment pattern is moved in the vertical or horizontal direction to find the position of the optical sensor, and then the position value of the converged convergence is detected from the position value of the optical sensor, and the position value of the converged convergence and the memory has already occurred. The error value of the convergence can be easily obtained by comparing the position value of the initial convergence stored in the.

However, since the error value of the detected convergence is a value detected only at the optical sensor located at the corner of the display unit, the entire convergence cannot be corrected accurately and accurately.

In order to accurately perform convergence correction, a large number of optical sensors may be disposed at the periphery of the display unit to detect error values of convergence.

However, the present invention can correct precise convergence using only up to four optical sensors, and allows the user to select the precision of the convergence correction.

That is, as shown in Figure 3, while moving the optical sensor located in the peripheral edge portion of the display unit according to the correction precision selected by the user, by detecting the error value of the convergence to accurately correct the error of the convergence.

4 is a flowchart illustrating an automatic convergence correction method of a projection TV according to the present invention.

First, at the factory, the converged error is corrected at the time of shipment of the projection TV to initialize the converged correction value.

At this time, the initially converged correction value is stored in the memory.

Subsequently, when an error of convergence occurs again due to environmental change or the surrounding geomagnetic field, the digital convergence control unit selects an alignment pattern of one of red, green, and blue colors through the RGB projector and displays the selected alignment pattern on the display unit. (S2)

Next, the distance between the alignment pattern and the optical sensor is measured to detect an error value of convergence, and the error value is stored in the memory (S3).

Subsequently, it is determined whether all the error values of the convergence of the red, green, and blue alignment patterns have been detected.

As a result of the determination, if all the error values of the convergence of the red, green, and blue alignment patterns are not detected, the alignment pattern of any one of the colors not selected among red, green, and blue is selected again, and the selected alignment pattern is displayed on the display unit. Repeat step S2.

If all the error values of convergence are detected as a result of the determination, it is judged whether or not to further detect the error values of convergence (S5).

As a result of the trial, if the error of convergence is not detected further, the digital convergence control unit corrects the error of convergence through the RGB projection unit according to the error value of the convergence stored in the memory (S6).

If the judging result further detects the error of convergence, it selects how precisely the convergence correction is detected (S7).

Subsequently, the system controller calculates the moving distance of the optical sensor according to the selected precision, and then drives the motor.

Then, the feeder starts to move by the motor, and the light sensor moves slowly along the guideline by the feeder (S9).

The system controller controls the driving of the motor to stop when the optical sensor is moved by the calculated moving distance.

Subsequently, at the position of the moved optical sensor, the alignment pattern of any one of red, green, and blue colors is again selected, and the step S2 of displaying the selected alignment pattern on the display unit is repeated.

The present invention according to the configuration and method as described above can not only correct the convergence very precisely with up to four optical sensors but also correct the error of the convergence with the accuracy desired by the user.

That is, according to the present invention, since the correction accuracy of the convergence can be variously produced by general adjustment, two-step adjustment, ultra-precision adjustment, and the like, the user can arbitrarily adjust the correction of the convergence.

In addition, the present invention has the advantage that the correction speed of the convergence is fast because the four optical sensors can perform the same detection operation at the same time.

In addition, as another embodiment of the present invention, when only one optical sensor is used, there is a disadvantage in that the correction speed of convergence is slower than when four optical sensors are used, but the circuit configuration is simple.

The automatic convergence correction apparatus and method of the projection TV according to the present invention has the following effects.

First, since the present invention corrects the error of convergence while moving the optical sensor, it can be corrected accurately and accurately.

Secondly, the present invention enables precise convergence correction even with a small number of optical sensors, so that the circuit configuration is simple, the price of the product is low, and high-speed processing is possible.

Third, the present invention improves the reliability of the convergence correction because the user can arbitrarily adjust the correction accuracy of the convergence.

Those skilled in the art will appreciate that various changes and modifications can be made without departing from the technical spirit of the present invention.

Therefore, the technical scope of the present invention should not be limited to the contents described in the embodiments, but should be defined by the claims.

Claims (11)

A display unit which displays an applied video signal; A movement guide unit disposed along a periphery of the display unit; At least one optical sensor moving along the movement guide part; A driving unit to move the optical sensor; A system controller which controls the driving unit, detects an error value of convergence from an output signal of the optical sensor, and outputs a control signal according thereto; And, And a digital convergence control unit configured to correct an error of the convergence displayed on the display unit according to a control signal of the system control unit. The apparatus of claim 1, wherein the movement guide unit is disposed on the rear surface of the display unit or is spaced apart from the rear surface of the display unit by a predetermined distance. The automatic convergence correction apparatus of a projection TV according to claim 1, wherein the optical sensor is composed of four parts and located at four corners of the movement guide part. 4. The apparatus of claim 3, wherein each optical sensor moves in a straight line along the movement guide unit. The method of claim 1, wherein the driving unit A transfer unit for moving the optical sensor; And a motor unit for driving the transfer unit according to the control signal of the system control unit. The automatic convergence correction apparatus of a projection TV according to claim 5, wherein the transfer unit is made of any one of a wire, a chain, a rail and a rubber belt, and the motor unit is a step motor. In the automatic convergence correction method of a projection TV having an optical sensor moving along the movement guide disposed in the periphery of the display unit, Initializing the convergence; Displaying an alignment pattern on the display unit; Detecting and storing an error value of convergence by measuring a distance between the light sensor and the alignment pattern; Determining whether to further detect the error of convergence; If it is determined that the error of the convergence is not detected further, correcting the error of the convergence according to the error value of the stored convergence, and if detecting the error of the convergence, selecting a correction precision of the convergence; Moving the optical sensor according to the selected correction precision; And, And repeating the steps of measuring a distance between the moved optical sensor and the alignment pattern to detect and store an error value of convergence. 8. The method of claim 7, wherein moving the optical sensor Determining a moving distance of the optical sensor according to the selected correction precision; Moving the optical sensor by the determined distance. In the automatic convergence correction method of a projection TV having an optical sensor moving along the movement guide disposed in the periphery of the display unit, Initializing convergence; Selecting an alignment pattern of one of red, green, and blue, and displaying the selected alignment pattern on the display unit; Detecting an error value of convergence by measuring a distance between the alignment pattern and the light sensor; Determining whether all error values of convergence of the red, green, and blue alignment patterns have been detected; Determining whether an error of the convergence is further detected, if all are detected; If it is determined that the error of the convergence is not detected further, correcting the error of the convergence according to the error value of the stored convergence, and if detecting the error of the convergence, selecting the correction precision of the convergence; Moving the optical sensor according to the selected correction precision; And, And selecting the alignment pattern of any one of the red, green, and blue colors, and repeatedly displaying the selected alignment pattern on the display unit. The display apparatus of claim 9, wherein if the error values of convergence of the red, green, and blue alignment patterns are not all detected, an alignment pattern of any one of red, green, and blue colors is selected, and the selected alignment pattern is displayed in the display unit. And repeating the steps of displaying on the projection TV. 10. The method of claim 9, wherein moving the light sensor Determining a moving distance of the optical sensor according to the selected correction precision; Moving the optical sensor by the determined distance.