KR20080067214A - Method for eliminating after-image of display apparatus - Google Patents

Abstract

A method for eliminating an afterimage of a display apparatus is provided to display a still screen and an inverted screen having inverted brightness and color and to obtain the same phosphor feature on the screen so as to remove the afterimage easily. A method for eliminating an afterimage of a display apparatus comprises the steps of; displaying an inputted image signal on a panel and detecting screen change volume(S5,S10); detecting the screen change volume and judging it as a still screen that a change over a predetermined value does not occur(S12); storing the displayed still screen(S14); judging whether the still screen is continuously displayed for more than set time(S16); generating the displayed still screen and an inverted screen in which brightness and color are inverted(S18); displaying the inversed screen for 20 minutes(S20,S22); displaying an entire screen with white color for 5 minutes(S24); and removing the afterimage, stabilizing a cell, and displaying the inputted image signal(S26).

Description

How to remove afterimages on display devices {METHOD FOR ELIMINATING AFTER-IMAGE OF DISPLAY APPARATUS}

1 is a block diagram schematically illustrating a configuration of a general display apparatus.

2 is a flowchart illustrating an afterimage removing method of a display apparatus according to an exemplary embodiment of the present invention.

   -Explanation of symbols for the main parts of the drawings-

10: AD converter 20: video signal processing unit

30: OSD generator 40: microcomputer

50: memory 60: key input unit

70: panel

The present invention relates to a method of removing an afterimage of a display device, and more particularly, when a still picture is displayed for a predetermined time or more through a display device, the entire still picture is displayed by displaying a still picture and a reversed screen in which brightness and color are reversed for a predetermined time. The present invention relates to a method for removing an afterimage of a display device, wherein the display device has the same phosphor characteristic to suppress and eliminate afterimage generation.

In general, the CRT (Cathode Ray Tube) has been the most commonly used as a display device, but the CRT has a problem that the weight is heavy, thick and consumes a lot of power. Recently, the active matrix driving type flat panel display has been replaced.

Such an active matrix driving type flat panel display device displays an image by controlling a light transmittance of a liquid crystal using a thin film transistor (hereinafter, referred to as TFT) as a switching element. Such liquid crystal display devices are widely used as PC monitors and TVs.

1 is a block diagram schematically illustrating a configuration of a general display apparatus.

As shown here, the input image format is determined according to the key input unit 60 for inputting a user's request command, the horizontal / vertical synchronization signal (H-Sync / V-Sync), and the clock (Clk). A microcomputer 40 for outputting a control signal so that a display conforming to a corresponding format, a memory 50 for storing data and setting values for controlling various systems according to the control signal of the microcomputer 40, and a microcomputer ( An OSD generator 30 for generating an OSD screen according to the control signal of 40), an AD converter 10 for converting an analog video signal into a digital video signal, a digital video signal output from the AD converter 10, The image signal processor 20 outputs the digital R, G, and B image signals by receiving the image signal output from the OSD generator 30 and is displayed, and outputs the image signal output from the image signal processor 20. For display It consists of a null (LCD or PDP) (70).

When the user inputs a desired command through the key input unit 60, the display device configured as described above may convert an analog video signal input from the AD converter 10 into a digital video signal according to a control signal of the microcomputer 40. The digital R, G, and B image signals input from the signal processor 20 are displayed on the panel 70 by screen adjustment and various image processing.

However, when such a display device is used as a PC monitor, the same video signal is input for a long time, so that the same image, that is, a still image, is often displayed for a long time. Often, a still image such as a long time is displayed.

However, in the display device as described above, when the still image lasts for a long time, the phosphor of the partition wall of the cell wears out, and an afterimage occurs between the bright and dark portions.

In addition, it may not react very quickly to a video signal, and thus afterimages of the previous still image remain when the still image is switched to another image after a long time. Such afterimages degrade the quality of the display device and cause dissatisfaction from consumers.

Therefore, in order to reduce such dissatisfaction, the entire screen is not recognized by the user, and the entire screen is moved in a circle in the order of left → down → right → up ... to suppress afterimage occurrence. .

However, in order to prevent afterimage and deterioration, the method of moving the screen left / right / up / down at a certain period is noticeable for instantaneous movement during still images and at the same time, the display blank is not overscanned in the display device. There is a problem that the section is noticeable.

The present invention has been made to solve the above problems, and an object of the present invention is to display a still image and a reversed screen in which brightness and color are reversed when the still image is displayed for a predetermined time or more through a display device. Accordingly, the present invention provides a method for removing an afterimage of a display device in which the entire screen has the same phosphor characteristic to suppress and remove an afterimage.

The present invention for achieving the above object comprises the steps of determining whether or not the still image of the input image signal, and if it is determined that the still image is stored after the still image and the still image is displayed continuously for a set time and If the still picture is maintained for a set time, inverting the stored still picture to generate a reversed picture; displaying the generated reversed picture for a set time; stabilizing the cell; And displaying a video signal.

In the present invention, the still picture is characterized by detecting the screen change amount of the input video signal.

In the present invention, the setting time is characterized in that 20 minutes.

In the present invention, if the still picture is displayed continuously for a set time characterized in that it further comprises the step of indicating that the afterimage removal operation is in progress.

In the present invention, the inverted picture is characterized in that the still picture and the brightness and color inverted screen.

In the present invention, the stabilization of the cell is characterized by displaying a white screen for 5 minutes.

According to the present invention, if the still picture is continuously displayed for a predetermined time or more, the inverted picture is displayed for the same time as the still picture displayed is inverted so that the entire pixel of the panel has the same phosphor characteristic to remove afterimages or to generate an afterimage. Will be suppressed.

Hereinafter, exemplary embodiments of the present invention will be described with reference to the accompanying drawings, and the same parts as in the prior art use the same reference numerals and names. In addition, this embodiment is not intended to limit the scope of the present invention, it is presented by way of example only and those skilled in the art will be able to many modifications within the technical spirit of the present invention.

2 is a flowchart illustrating an afterimage removing method of a display apparatus according to an exemplary embodiment of the present invention.

First, the screen change amount is detected while displaying the input video signal on the panel 70 (S5) (S10).

At this time, if the screen change amount is detected and no change occurs over a predetermined value, it is determined as a still picture (S12).

When it is determined that the still image is thus stored, the displayed still image is stored (S14).

Then, it is determined whether the still picture is continuously displayed for a predetermined time or more (S16).

For example, if the still image is not displayed continuously for more than 20 minutes, it is determined that an afterimage has not occurred, and the screen change amount of the input image signal is continuously detected to determine whether the still image is still present.

However, when the still picture is displayed continuously for 20 minutes or more, an operation for removing an afterimage is performed.

As described above, before the afterimage removal operation is performed, the user may be notified that the afterimage removal operation is performed along with the afterimage warning through the OSD screen to notify the user that the afterimage removal operation is performed.

The afterimage removal operation generates a still image that is continuously displayed for the afterimage removal, and an inverted image in which brightness and colors are reversed (S18).

By displaying the generated inverted image for the set time during which the still image is displayed, that is, for 20 minutes, the still image is displayed and the pixels of which the characteristic is changed and the surrounding pixels have the same phosphor characteristics (S20) (S22).

In other words, the dark pixels in the still image are brightened by the inverted image, and the bright pixels in the still image are darkened in the inverted image so that the phosphor characteristics of all the pixels are the same.

After the phosphor characteristics of the pixels are the same, the entire screen is displayed in white for 5 minutes to stabilize the cell (S24).

After removing the afterimage caused by the still image and stabilizing the cell, the input image signal is displayed (S26).

As described above, when the still picture is displayed for a predetermined time or more through the display device, the present invention displays the still picture displayed and the inverted picture in which brightness and color are inverted for a predetermined time so that the entire screen has the same phosphor characteristic so that afterimages are generated. There is an advantage that can be suppressed as well as eliminated.

Claims (6)

Determining whether the input image signal is a still image; Determining whether the still picture is continuously displayed for a predetermined time after the still picture is stored when the still picture is determined as the still picture; Generating a reversed screen by inverting the stored still screen when the still screen is maintained for the set time; Stabilizing a cell after displaying the generated reverse screen for the predetermined time; After stabilizing the cell, displaying an input image signal Afterimage removal method of the display device, characterized in that consisting of. The method of claim 1, wherein the still picture is detected by determining a screen change amount of an input video signal. The method of claim 1, wherein the set time is 20 minutes. The afterimage removing method of claim 1, further comprising displaying an afterimage removing operation when the still image is continuously displayed for the set time. The method of claim 1, wherein the inverted screen is a screen in which brightness and color are inverted from the still screen. The method of claim 1, wherein the stabilization of the cell displays a white screen for 5 minutes.

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