KR100218107B1 - Convergence correction device & the method of a projection tv - Google Patents

Abstract

The present invention relates to a projection TV, and in particular, the image shift of the RGB screen according to the change of the geomagnetic field in each country and the direction of the north, south, east, west, and north directions, by detecting the convergence correction signal carried in the blanking section of the broadcast signal, calculating the convergence change amount, and then determining the CRT. By automatically correcting the misconvergence of the RGB screen by controlling, the projection TV can improve the fatal problem that convergence is distorted due to the influence of the geomagnetic field, which can ensure high quality image quality, and to maintain the uniform image size. The present invention also relates to an apparatus and method for automatically correcting convergence of a projection TV that can remove the conventional function of adjusting the coincidence and thus increase productivity efficiency.

Description

Projection TV convergence automatic correction device and method

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a projection TV, and more particularly, to an apparatus and method for automatically correcting convergence of a projection TV by detecting an amount of change in convergence according to a phase shift of a screen for each country and direction, and automatically correcting RGB convergence of the screen. .

In general, projection TVs and projectors adjust the image size and convergence by adjusting the geomagnetism to match the geomagnetism of the country at the time of production.The CRT has three red, green, and blue tubes, and each CRT Since there is a difference by location, even if the screen convergence is perfect through the geomagnetic field correction, there is a problem that the screen convergence is shifted or the phase of the screen is shifted according to the country or the east, west, north, and south directions.

In order to solve the above problem, conventionally, by adjusting the DC bias applied to the CRT deflection coil through a plurality of variable resistors installed in the projection TV to correct the misconverged screen of the projection TV, the electronic direction in the CRT is adjusted. Control and adjust the misconvergence of the RGB screen.

Therefore, as described above, since the screen convergence of the unwanted portion is changed when adjusting the screen convergence through the plurality of variable resistors installed in the TV, it is impossible to accurately adjust the corners of the screen, and also the plurality of variable resistors. It was a hassle to match RGB screens one by one.

In order to solve the problems of the prior art, the present invention detects a correction signal loaded on a blanking section of a broadcast signal through an RGB light-receiving sensor on a screen by shifting an image on a screen according to a change in a geomagnetic field for each country, east, west, north, and north directions. The present invention provides an apparatus and method for automatically adjusting convergence of projection TV for automatically correcting misconvergence of an RGB screen by detecting and determining a change amount of convergence.

In order to achieve the above object, the apparatus of the present invention comprises a tuner for receiving the convergence correction signal and the broadcast signal in a projection set for mixing and transmitting a screen convergence correction signal in a predetermined blanking period and receiving the convergence correction signal. Wealth; An image receiving circuit unit for amplifying and detecting a signal output from the tuner unit; A synchronization deflection circuit unit which removes the video signal from the broadcast signal branched from the video reception circuit unit, detects only the synchronization signal, and separates the image signal into vertical and horizontal synchronization signals; Receiving a convergence correction signal output from the image receiving circuit unit and scanning the correction signal on the screen in the vertical and horizontal directions under the control of the current applied to the deflection coil according to the horizontal and vertical synchronization signals output from the synchronous deflection circuit unit. CRT; Correction signal detecting means provided at a predetermined position on the screen and detecting a screen correction signal of the predetermined RGB signal scanned on the screen; And after receiving and calculating a detection signal output from the correction signal detecting unit, determines a direction in which an RGB screen is distorted, and outputs an RGB control signal corresponding thereto to the synchronous deflection circuit to output a current applied to the RGB deflection coil of the CRT. And a phase correction controller for controlling to correct misconvergence of the RGB screen.

In addition, in order to achieve the above object, the operation method of the present invention comprises the steps of: detecting a predetermined screen convergence correction signal carried in the blanking section of the broadcast signal with the correction signal detection means; After performing the above steps, receiving and calculating a predetermined signal output from the correction signal detecting means, and determining whether a predetermined convergence correction signal has been detected; When the convergence correction signal is detected in the above step, the screen is controlled up, down, left, and right by controlling the strength and direction of the magnetic field of the RGB deflection coil of the CRT with the vertical and horizontal synchronization signals corrected according to the predetermined control signal. Moving and adjusting in the direction of; And after performing the above steps, receives and outputs a signal output from the correction signal detecting unit, determines whether a predetermined convergence correction signal is detected, and if no convergence correction signal is detected, it is determined that each RGB CRT is converged. And terminating the convergence correction step.

1 is a block diagram showing a convergence correction device according to an embodiment of the present invention.

FIG. 2 is a diagram showing an installation example of the correction signal detecting means of FIG.

3 is a flowchart illustrating the operation of FIG. 1.

* Explanation of symbols for main parts of the drawings

10: Tuner part. 15: Image receiving circuit section.

20: color signal reproduction circuit section. 25: Synchronous deflection circuit section.

30: CRT (Cathode-Ray Tude). 35: screen.

40: Correction signal detection means (RGB light receiving sensor).

45: phase correction control unit.

Hereinafter, the present invention will be described in more detail with reference to the accompanying drawings.

1 is a block diagram showing a convergence correction device according to an embodiment of the present invention, a tuner unit 10, an image receiving circuit unit 15, a color signal reproduction circuit unit 20, a synchronous deflection circuit unit 25 and And a CRT 30, a screen 35, a correction signal detecting means 40, and an image correction control unit 45.

On the other hand, the tuner 10 is configured to receive a convergence correction signal and a broadcast signal transmitted by mixing the screen convergence correction signal in a predetermined blanking period, select a predetermined broadcast channel, and amplify the received signal.

In addition, the image receiving circuit unit 15 is configured to amplify, detect, and amplify the signals output from the tuner unit 10, and the color signal reproducing circuit unit 20 is branched from the image receiving circuit unit 15. It is configured to detect, demodulate and amplify a carrier color signal component of a broadcast signal to output a primary color signal or a color difference signal, and the synchronous deflection circuit section 25 removes the video signal from the broadcast signal branched from the video reception circuit section 15. And it detects only the synchronization signal and is configured to separate and output the vertical and horizontal synchronization signals (Vsync, Hsync).

In addition, the CRT 30 receives the convergence correction signal output from the image reception circuit unit 15 or the color signal reproduction circuit unit 20, and each of RGB in accordance with the horizontal and vertical synchronization signals output from the synchronization deflection circuit unit 25. The control signal is configured to scan the correction signal on the screen 35 in the horizontal and vertical directions by controlling the current applied to the deflection coil.

Further, the correction signal detecting means 40 is configured to detect a screen correction signal (luminance level) of a predetermined RGB signal which is provided at an arbitrary position on the screen 35 and scanned on the screen.

In addition, the image correction controller 45 receives the correction signal output from the correction signal detecting means 40, calculates the direction in which the RGB screen is twisted, and converts the corresponding RGB correction control signal into the synchronous deflection circuit unit ( 25) to control the amount of current of the RGB deflection coil of the CRT 30 and to converge the RGB screen.

That is, an arbitrary screen convergence correction signal, that is, a luminance signal or the like, is mixed and transmitted in a blanking section (vertical and horizontal blanking period) in which the TV broadcast signal does not carry a video signal, and the screen correction signal carried in the blanking section is set during the set operation. Detects and amplifies and outputs the result to the CRT (30).

The convergence correction signal is scanned on the screen 35 through the CRT 30 in accordance with the synchronization signal output from the synchronization deflection circuit section 25.

In addition, the correction signal detecting means 40 detects a convergence correction signal carried in the blanking section scanned from the CRT 30 and outputs a signal corresponding thereto. That is, when the RGB CRT 30 is correctly corrected, it is preferable that the correction signal is not detected by the correction signal detecting means 40. When the correction signal is detected by the correction signal detecting means 40, the convergence of the CRT 30 is detected. Is turned on to indicate that the screen is shifted.

Subsequently, the image correction controller 45 receives a convergence correction signal (with or without a correction signal or a predetermined output voltage) output from the correction signal detecting unit 40 to calculate the shift state of the RGB screen, and then calculates the RGB CRT. The control signal for correcting the misconvergence of (30) is output to the synchronous deflection circuit section 25.

The synchronous deflection circuit section 25 controls the amount of current applied to the RGB deflection coil of the CRT 30 to move the RGB screen in predetermined directions in the up, down, left, and right directions and corrects convergence.

FIG. 2 is a diagram showing an installation example of the correction signal detecting means 40 of FIG. 1, which is installed inside the screen on the outer portion of the screen 35 on which the image is not displayed or on the edge of the screen to be used. It is preferable to construct.

The RGB light receiving sensor 40 is installed at a plurality of edges of the screen to detect the RGB convergence correction signal carried in a predetermined blanking period (vertical, horizontal blanking period) for each position, and according to the presence or absence of the detection of the convergence correction signal After determining each screen shift state, the RGB screen correction operation is performed.

FIG. 3 is a flowchart illustrating the operation of FIG. 1, and the overall operation of the present invention will be described with reference to the accompanying drawings.

First, a step of sensing a predetermined screen convergence correction signal carried in a blanking section of a broadcast signal by a plurality of RGB light receiving sensors 40 installed at an edge of the screen 35 is performed (S1).

After performing the step S1, the phase correction controller 45 receives and calculates predetermined signals output from the RGB light receiving sensors 40, and determines whether a predetermined convergence correction signal has been detected. Perform (S2). That is, for example, the correction signal loaded in the blanking section is a luminance signal of a predetermined level, and determines whether a signal corresponding thereto is detected by the RGB light receiving sensor 40.

When the convergence correction signal is detected in the step S2, the phase correction controller 45 outputs a predetermined control signal to the synchronous deflection circuit unit 25, and the CRT ( Step 30 is performed to control the intensity and direction of the magnetic field of the RGB deflection coil to move the screen in predetermined directions in the up, down, left and right directions (S3).

After performing step S3, the phase correction controller 45 receives the signal output from the RGB light receiving sensor 40, calculates it, and determines whether a predetermined convergence correction signal has been detected. If not, it is determined that the RGB screen has been converged and the process of terminating the RGB screen convergence correction step is performed (S4).

However, when a convergence correction signal is detected in the correction signal detection step S4, the step of moving and adjusting the RGB screen in a predetermined direction is performed again (S3).

In addition, the present invention can be applied not only to the projection TV of the rear projection type but also to the projector of the front projection type.

Therefore, as described above, in the present invention, the convergence correction signal is detected by the correction signal detecting means, thereby improving the fatal problem that the projection TV is distorted due to the influence of the geomagnetic field, thereby ensuring high quality image quality, and providing a uniform image size. In order to maintain the efficiency of productivity can be improved by eliminating the conventional function of adjusting the color matching of each RGB.

Claims (5)

In the projection set for mixing and transmitting the screen convergence correction signal in a predetermined blanking interval, and receiving the convergence correction signal, A tuner unit configured to receive the convergence correction signal and the broadcast signal; An image receiving circuit unit for amplifying and detecting a signal output from the tuner unit; A synchronization deflection circuit unit which removes the video signal from the broadcast signal branched from the video reception circuit unit, detects only the synchronization signal, and separates the image signal into vertical and horizontal synchronization signals; Receiving a convergence correction signal output from the image receiving circuit unit and scanning the correction signal on the screen in the vertical and horizontal directions under the control of the current applied to the deflection coil according to the horizontal and vertical synchronization signals output from the synchronous deflection circuit unit. CRT; Correction signal detecting means provided at a predetermined position on the screen and detecting a screen correction signal of the predetermined RGB signal scanned on the screen; And after receiving and calculating a detection signal output from the correction signal detecting unit, determines a direction in which an RGB screen is distorted, and outputs an RGB control signal corresponding thereto to the synchronous deflection circuit to output a current applied to the RGB deflection coil of the CRT. And a phase correction controller for controlling to compensate for the misconvergence of the RGB screen by controlling the projection TV. The apparatus of claim 1, wherein the correction signal detecting unit is installed at an outer portion of the screen on which the image is not displayed or inside the screen at the edge of the use screen. The apparatus of claim 1, wherein the correction signal detecting means comprises a plurality of RGB light receiving sensors. Detecting, by the correction signal detecting means, a predetermined screen convergence correction signal carried in the blanking section of the broadcast signal; After performing the above steps, receiving and calculating a predetermined signal output from the correction signal detecting means, and determining whether a predetermined convergence correction signal has been detected; When the convergence correction signal is detected in the above step, the screen is controlled up, down, left, and right by controlling the strength and direction of the magnetic field of the RGB deflection coil of the CRT with the vertical and horizontal synchronization signals corrected according to the predetermined control signal. Moving and adjusting in the direction of; And After performing the above steps, the signal output from the correction signal detecting means is calculated to determine whether a predetermined convergence correction signal is detected, and if the convergence correction signal is not detected, it is determined that the RGB CRT is converged and convergence correction is performed. A method for automatically correcting convergence of a projection TV, characterized in that the step of ending the step. 5. The method of claim 4, wherein if a convergence correction signal is detected in the detection of the correction signal, moving and adjusting the RGB screen in a predetermined direction is performed again.

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