KR19990040249A - Auto Convergence Control - Google Patents

Abstract

The auto-convergence adjustment device is to find the center of the screen of the projection TV and adjust the convergence automatically. The present invention provides a sensor unit comprising at least two photosensors installed at appropriate positions in a horizontal and vertical direction corresponding to a predetermined center of the screen, and for each of red (R), green (G), and blue (B). The pattern generator which generates a cross pattern (+), and the horizontal and vertical convergence values of the red (R), green (G), and blue (B) color signals are changed by a predetermined step from minimum to maximum. The microcomputer is configured to automatically adjust the convergence to the convergence value when the cross pattern is detected by the sensor unit while moving the + pattern. Accordingly, the present invention provides convenience for the user since the user automatically corrects the convergence distortion caused by the influence of the geomagnetic field according to the installation direction of the projection TV without the manual operation while watching the screen.

Description

Auto Convergence Control

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic convergence adjustment device, and more particularly, to an automatic convergence adjustment device that enables automatic adjustment of convergence due to the influence of a geomagnetic field that depends on the installation direction of a projection TV.

In general, Projection TV has a merit that the screen is clear and large in size as a rear projection method that projects an image from the back of the screen, unlike the front projection method of projecting an image onto a screen. In such a projection TV, red (R), green (G), and blue (B) deviate from each other, resulting in color distortion, which degrades image quality and reduces peripheral focus. Therefore, convergence alignment is required to focus on one point so that red (R), green (G), and blue (B) do not deviate. These include static convergence, which adjusts the concentration near the center of the screen, and dynamic convergence, which adjusts the concentration at the periphery. This convergence is adjusted before the TV ships. However, the projection TV has a phenomenon in which convergence is distorted due to the change of the geomagnetic direction relative to the installation direction. Therefore, an apparatus for correcting convergence distortion caused by relative geomagnetic field changes has been required.

Conventionally, in order to compensate for the convergence distortion due to the influence of the geomagnetic field, the convergence correction amount according to the installation direction of the TV is stored in the memory in the set in advance, and the geomagnetic field correction is performed by using the convergence correction amount that the user manually selects while viewing the screen among the stored convergence correction amounts. Was done.

However, in the related art, there is a inconvenience in that the user must manually adjust the convergence according to the viewer's judgment while watching the current viewing screen.

Accordingly, an object of the present invention is to provide an automatic convergence adjustment device that can adjust the convergence automatically by finding the center of the screen of the TV in order to solve the above problems.

1 is a block diagram showing an automatic convergence adjustment device according to the present invention;

2 is a flowchart for explaining an operation of the apparatus of FIG. 1;

3 is a state diagram for explaining an installation state and a detection point of the sensor unit of FIG.

<Description of Symbols for Main Parts of Drawings>

10: sensor unit 20: micom

30: pattern generator

The automatic convergence adjustment device of the present invention for achieving the above object, in the projection TV, the pattern generating unit for generating a pattern for finding the center of the screen to display on the screen, and a predetermined center on the screen A sensor unit installed at a predetermined position in a corresponding horizontal and vertical direction to detect when the pattern is displayed at the position, and changing the horizontal and vertical convergence values to move the position of the pattern displayed on the screen; And a microcomputer that automatically adjusts the convergence to the horizontal and vertical convergence values when the pattern is detected by the negative.

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

1 is a block diagram of an automatic convergence adjustment device according to an embodiment of the present invention. The apparatus shown in FIG. 1 includes a sensor unit 10 including at least two photo sensors installed at appropriate positions in a horizontal and vertical direction corresponding to a center of a preset screen, and red (R) and green (green) sensors. Pattern generator 30 for generating a cross pattern (+) to find the horizontal and vertical positions of the screen center with respect to (G) and blue (B), respectively, and red (R), green (G), and blue (B) The microcomputer 20 obtains a convergence value when detected by the sensor unit 10 while changing the horizontal and vertical stack convergence values for each of them. An operation of the apparatus of FIG. 1 having such a configuration will be described with reference to FIGS. 2 and 3.

In order to automatically adjust static convergence by finding a predetermined center on the TV screen, as shown in FIG. 3, a sensor unit including a photo sensor at a predetermined position corresponding to the horizontal and vertical directions of the predetermined center on the TV screen ( 10) is installed. The sensor unit 10 is composed of at least two photosensors corresponding to the horizontal and vertical directions of the screen center, and as shown in FIG. 3, four photosensors are installed at both positions in the horizontal and vertical directions of the screen center. It consists of (11A, 11B) 12A, 12B. When the automatic convergence is "ON" by the user when moving the set of the projection TV or when changing the installation direction, the microcomputer 20 first controls the pattern generator 30 to form a cross pattern (+) for the enemy (R). "ON" (step 201). The pattern generator 30 generates a cross pattern (+) for the red (R) under the control of the microcomputer 20 to display on the TV screen. The microcomputer 20 changes the static convergence values RH and RV in the horizontal and vertical directions with respect to the enemy R in steps from minimum to maximum (step 202). A cross-shaped (+) for the enemy R generated by the pattern generator 30 at a position on the screen corresponding to the static convergence values RH and RV in the horizontal and vertical directions with respect to the enemy R changed in step 202. The pattern is displayed. The sensor unit 10 detects when the cross pattern (+) is located near the predetermined center of the screen (step 203). That is, as shown in FIG. 3, the sensor unit 10 outputs a "low" level signal when a cross pattern (+) pattern is not detected, and a "high" level signal when a cross pattern (+) is detected. Output to the microcomputer 20. If the detection point by the sensor unit 10 has multiple detection points, the microcomputer 20 takes the convergence value of the step corresponding to the center point among the detected points (step 204), and controls the pattern generator 30 to control the red dot. The cross pattern (+) for (R) is " OFF " (step 205). Then, the microcomputer 20 "ON" the cross pattern for green G and perform the above steps to perform horizontal and vertical static convergence values corresponding to the center of the screen for green G. (GH, GV) is taken (step 206). The microcomputer 20 also performs the above steps by "on" the cross pattern (+) for blue (B) to perform horizontal and vertical static convergence values corresponding to the center of the screen for blue (B). BH, BV) (step 207). The microcomputer 20 statically converges the horizontal and vertical static convergence values (RH, RV, GH, GV, BH, BV) of red (R), green (G), and blue (B) corresponding to the center of the screen. It outputs to the yoke and automatically performs horizontal and vertical convergence correction by the geomagnetic field of the projection TV (step 208).

As described above, the automatic convergence adjustment device of the present invention finds the center of the screen of the projection TV and automatically adjusts the convergence so that the user does not need to manually adjust while watching the screen, so that the image is always displayed in the correct position on the screen. Has an effect.

Claims (5)

In projection TV, A pattern generator for generating a pattern for finding the center of the screen and displaying the pattern on the screen; A sensor unit installed at predetermined positions in horizontal and vertical directions corresponding to a predetermined center portion on a screen to detect when the pattern is displayed at the position; And And a micom that automatically adjusts the convergence to the horizontal and vertical convergence values when the pattern is detected by the sensor unit while moving the position of the pattern displayed on the screen by changing the horizontal and vertical convergence values. The apparatus of claim 1, wherein the pattern generator generates a cross pattern (+) for each of red (R), green (G), and blue (B). The automatic convergence adjustment apparatus of claim 1, wherein the sensor unit comprises at least two photosensors. The method of claim 2, wherein the microcomputer crosses the horizontal and vertical convergence values of the red (R), green (G), and blue (B) signals in steps of minimum to maximum and is displayed on the screen. +) Automatic convergence adjustment device, characterized by moving the position of the pattern. The method according to claim 4, wherein when the pattern is detected at various points by the sensor unit, the micom outputs the red (R), green (G), and blue (B) color signals in a step corresponding to the center point among the detection points. An automatic convergence adjustment device, characterized in that the convergence is adjusted by the horizontal convergence value and the vertical convergence value.