KR101441689B1 - Method and apparatus for preventing an ocular spectrum of (a) screen of (an) image display device - Google Patents

Abstract

The present invention relates to an image display device, which includes a step of receiving a residual image removal mode request signal, a step of confirming a luminance of an image to be displayed according to a received signal, a step of detecting at least one image, The method comprising the steps of:

Image display device, afterimage removal

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image display device,

The present invention relates to an image display apparatus, and more particularly, to an apparatus and method for removing an afterimage of an image display apparatus that can effectively prevent or remove an afterimage in an image display apparatus in which a residual image may occur.

In a video display device, a television is a video device that selects and demodulates a broadcast signal according to a channel selected by a user among broadcast signals transmitted from a broadcasting station, separates the broadcast signal into audio and video, and outputs the broadcast and audio through a screen and a speaker There are TVs using CRT (Cathod Ray Tube), LCD (liquid crystal display) which satisfies high definition / large screen characteristics, and PDP (Plasma dislay Panel).

In particular, PDP TVs can be manufactured much thinner than conventional CRTs due to their structural characteristics, and they have excellent luminance characteristics compared to LCDs and can realize high-definition large-screen displays. Therefore, they have excellent layout characteristics such as wall mounting, Be in the spotlight.

However, when a specific character is displayed for a long time or a wide screen is set for a long time depending on the application or according to the display purpose, the LCD product group leaves a long afterglow on the boundary portion, Which may cause fatal damage to the product.

In addition, most image display devices have a line-by-line or pixel-by-pixel voltage version, which results in a voltage-independent version of the result. In this case, the common voltages are all the same, The afterimage and the screen cell deteriorate due to an external environmental cause. If this still image is displayed for a long time, after-image or deterioration may occur.

For example, in the case of an image display device capable of displaying an operation schedule installed at a terminal or an airport, only a part of characters or numerical symbols are changed in a table of the same format, Display. In addition, since a screen displayed by a character or a graphic in the image of a TV transmission or an image often displays the same screen for a long time, the image of the previous screen remains and the image sticking phenomenon occurs even if the screen is switched.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an image display device having an effective afterimage-removing function.

It is another object of the present invention to provide an image display device that performs a residual image removal function according to the type and brightness of an image according to a user's selection or an internal function of the image display device.

As described above, according to an aspect of the present invention, there is provided a method of displaying a video image, the method comprising: receiving a afterimage removal mode request signal; confirming a luminance of an image to be displayed according to a received signal; And displaying it for a predetermined period of time.

According to another aspect of the present invention, there is provided an image display apparatus including a display unit for displaying an image and displaying an afterimage-free image with respect to the image, a luminance unit for extracting a luminance value for an image to be displayed on the display unit, And a controller for controlling the grayscaling to perform grayscaling according to the brightness extracted from the video signal processor and displaying the afterimage-free image of the brightness value extracted through gray scaling, do.

As described above, the present invention has the effect of performing the afterimage removal function quickly and easily in the image display device and performing the afterimage removal mode that minimizes the loss of the displayed image even during the afterimage removal mode .

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

1 is a block diagram of a video display device to which the present invention is applied. Hereinafter, an image display device for implementing the embodiment will be described in detail with reference to FIG.

The image display device 100 to which the present invention is applied may include a receiving unit 110, a processing unit 120, an output unit 130, a control unit 140, a memory unit 150, and an interface unit 170.

The receiving unit 110 may include an external signal input unit 111 and a tuner unit 112. The processing unit 120 includes an image / audio signal switching unit 121, an A / D converter 122, A video / audio signal processing unit 123 and an image memory unit 124. The output unit 130 includes a video signal output unit 131, a display unit 132, a voice signal output unit 133, And a speaker 134.

The external signal input unit 111 receives a signal received from an external device such as a digital versatile disk (DVD), a set top box, a camcorder, or the like, and provides the signal to the video / audio signal switching unit 121. The external signal input unit 111 according to the embodiment of the present invention stores a plurality of images and the like and reads the image by a user's request and displays the image on the display unit 132 of the image display device 100, And an external storage medium for storing the edited image.

The tuner unit 112 tunes at least one channel according to a control signal of the controller 140 and decodes or separates the video / audio / data signals received through the tuned channel, ).

The video / audio signal switching unit 121 selects at least one channel among the channels provided from the external signal input unit 111 and the tuner unit 112 and separates the video / audio signal of the channel A post-MPEG decoder and a video / audio signal processor 123, and the like. The video / audio signal switching unit 121 may include a demultiplexer capable of separating video / audio / data signals.

When the signal selected by the video / audio signal switching unit 121 is an analog signal, the video signal and the audio signal of the analog signal are separated, and the analog video signal is converted into a digital video signal by the A / D converter 122 An MPEG decoder and a video / audio signal processing unit 123, and the analog audio signal may be provided to the audio signal output unit 133. If the signal selected by the video / audio signal switching unit 121 is a digital signal, both the video signal and the audio signal of the digital signal can be provided to the MPEG decoder and the video / audio signal processing unit 123.

The MPEG decoder and the video / audio signal processing unit 123 restore and process the video / audio stream among the output signals of the video / audio signal switching unit 121 as video / audio data, The audio signal provided to the video signal output unit 131 and processed is supplied to the audio signal output unit 133. The MPEG decoder and video / audio signal processor 123 may mix the OSD data provided by the controller 140 and the restored and processed video signals.

In particular, the MPEG decoder and the video / audio signal processor 123 according to the embodiment of the present invention check the brightness of the image output to the display module 132 and perform gray scaling according to the brightness of the image, And performs a function of extracting adjacent gray tones. And processes the image for outputting the afterimage-free image so that the gray tone is displayed on the corresponding pixel (Dot) in a mosaic form on the original image.

The image memory unit 124 provides a memory area required for decoding and signal processing of the MPEG decoder and the video / audio signal processor 123. Particularly, the image memory unit 124 can be used in a search step for searching for another channel broadcasting the same content as the memory unit 150. When the symbol use step and the image comparison step are performed, Used to compare.

The video signal output unit processes the video signal output from the MPEG decoder and the video / audio signal processing unit 123 in a form that can be outputted through the display unit 132. The audio signal output unit 133 processes the video signal output from the MPEG decoder and the video / And processes the voice signal output from the voice signal processing unit 123 in such a form that it can be outputted through the speaker 134. [

In particular, the display module 132 according to an exemplary embodiment of the present invention displays a menu and a progress state according to a user's request, and displays a residual image.

The interface unit 170 may be, for example, a local key button provided in a remote controller or a video display device. The interface unit 170 receives various commands and information from a user, converts the command into information, and transmits the control signal to the controller 140. Therefore, according to an embodiment of the present invention, a menu input and an operation request signal according to an afterimage mode operation are received from a user according to an embodiment of the present invention.

In addition, the interface unit 170 performs a function of receiving a gray tone corresponding to the brightness of an image during gray scaling from a user or receiving an extraction request signal.

The control unit 140 controls the tuner unit 112, the video / audio signal switching unit 121 and the MPEG decoder and the video / audio signal processing unit 123, and also controls other components of the video display device 100 And can be designed and connected for control.

The control unit 140 may store the video / audio signals output from the video / audio signal switching unit 121 and the MPEG decoder and the video / audio signal processing unit 123 in the memory unit 150, And can be provided to the MPEG decoder and the video / audio signal processor 123 by reading the stored video / audio signals.

The control unit 140 checks whether the display time of the display image or the image is switched according to the embodiment of the present invention, and performs the afterimage removal mode accordingly. Further, the control unit 140 controls to perform gray scaling for extracting gray tones according to the brightness of the image, and controls to display the afterimage-free image with the extracted gray tones.

The memory unit 150 includes a control memory unit 152 and a data memory unit 154. The control memory unit 152 stores information input by the user or data generated and managed by the control unit 140. [ The data memory unit 154 also stores a data broadcast signal or the like received from the outside according to a user's request.

As described above, the video display device according to the present invention outputs the video signal received through the tuner unit 112 or the external signal input unit 111 through the display unit 132 through the predetermined processing in the processing unit 120 . In this case, when the user input through the interface unit 160 or the same video output or image switching for a predetermined time occurs in the control unit 140, the MPEG decoder and the video / audio signal processor 123 perform the afterimage- So that the image is displayed on each pixel (Dot) by a predetermined rule.

Hereinafter, the afterimage removal operation in the image display device according to the embodiment of the present invention will be described in detail with reference to FIG. 2 through FIG.

FIG. 2 is a flowchart of a residual image removal operation according to an embodiment of the present invention. FIG. 3 is a diagram illustrating a screen displayed when a menu for a residual image removal operation is selected in FIG. FIG. 7 is a view illustrating a screen displayed in the afterimage removal operation according to an embodiment of the present invention. FIG.

The control unit 140 of the video display device 100 displays a video signal output mode for displaying the video signal requested by the user or received through the tuner unit 112 or the external signal input unit 111 on the display unit 132 (Step 205)

When a menu selection signal for setting various functions of the video display device is inputted from the user through the interface unit 170 during the video output mode in operation 210, the submenus according to the selected adjustment menu are displayed. FIG. 3 is a diagram illustrating an example of a screen displaying a sub menu according to an adjustment menu selected by a user.

When the menu is selected in the video output mode, a menu capable of adjusting various functions is displayed on the video display device as shown in the screen example of FIG. 3 (a). 3 (b), the user selects the afterimage removal menu to perform the afterimage removal mode of various menus as shown in FIG. 3 (a) according to the embodiment of the present invention.

Thereafter, the control unit 140 selects a residual image removal method to be performed according to the selected residual image removal menu (step 230). In addition to the conventional method of moving and reversing according to the residual image removal method, the control unit 140 determines whether the gray scaling method is selected as shown in FIG. 3C (step 235). If the gray scaling method is not selected, (Step 240)

On the other hand, if a signal for performing the afterimage-removing operation through grayscaling is inputted from the user, the controller 140 checks the brightness of the image currently displayed. (Step 245) ≪ / RTI > method.

The control unit 140 performs gray scaling to extract similar gray tones according to the identified brightness as illustrated in the screen example of FIG. 4. (Operation 250) FIG. And a gray-tone of a luminance similar to the luminance of the displayed display image is searched to perform the afterimage-removing mode with the corresponding gray-tone.

When the gray scaling is performed, a bar indicating progress of gray scaling or the like may be displayed on the display unit 134 as shown in a screen example of FIG. Alternatively, the user may receive a key input through the interface unit to search for gray in a tone similar to the luminance of the image in grayscaling, and extract the gray tone.

For example, when a signal for performing gray scaling is inputted, a bar of a horizontal / vertical form is displayed on the display module 132 as shown in the example of FIG. 4, ), And white (255, 255, 255), so that a gray tone corresponding to the brightness of the image can be extracted. At this time, the brightness value and the position of the gray tone corresponding to the brightness of the identified image can be displayed, and the user can manually extract the gray tone by moving the arrow through the key input.

In operation 255, the control unit 140 performs the afterimage removal mode using the gray-tone extracted through the gray-scaling. (Step 255) In the embodiment of the present invention, the extracted gray- 7 (a). In this case, the gray tone may be given a semi-transparent effect so as to further reduce the loss of the original image.

Also, the controller 140 may display the afterimage-free image as shown in FIG. 7A according to the user's setting, and for the pixels that have not displayed the afterimage-removed image as shown in FIG. And the pixel which has displayed the previous afterimage-free image may display the original image repeatedly by the number of times requested by the user or by the threshold number of times.

In operation 260, the control unit 140 determines whether the afterimage removal mode has been completed. If the afterimage removal mode has been completed, the controller 140 continues to display the output of the previous image.

As described above, in the afterimage-removing method according to an embodiment of the present invention, when the user selects the afterimage-removing menu among the various menus of the video display device and then performs the afterimage-removing mode of the gray- And performs gray scaling to extract the luminance and the gray tone close to the luminance.

Then, when the gray-tone extraction through the gray-scaling is completed, the gray-tone image is displayed on each dot in a mosaic form as if the mosaic image is superimposed on the original image.

Or the flowchart shown in Fig. 4 is a flowchart of a residual image removal operation according to another embodiment of the present invention. For a similar operation to the above-described one embodiment, a detailed description will be briefly referred to.

The control unit 140 determines whether the same (or stopped) image is output for a predetermined threshold time during the video output mode (step 405). When it is confirmed that the same (or still) image is continuously displayed for the threshold time, the OSD informing the user to perform the afterimage cancellation mode is displayed (step 415). Thereafter, the afterimage cancellation algorithm similar to the operation of the embodiment described above (Steps 420 to 440)

At this time, similarly to the embodiment, manual extraction by user input is possible when extracting gray tones according to brightness of an image.

In addition, a residual image removing method according to still another embodiment of the present invention will be described with reference to FIG.

If it is detected in step 510 that the same image has been displayed for a predetermined time period, the control unit 140 determines whether the previous image is displayed for a predetermined threshold time (step 515) )

If the same image is not displayed for the threshold time as a result of the determination, the control unit 140 controls to display the image on the switched screen (step 545). On the other hand, if the controller 140 determines that the same image is displayed during the threshold time, The OSD indicating the removal mode execution is displayed on the display unit 134 in step 520 and then the afterimage removal algorithm according to the embodiment of the present invention is performed.

1 is a block diagram of a video display device to which the present invention is applied.

2 is a flowchart of a residual image removal operation according to an embodiment of the present invention;

3 is a diagram illustrating a screen displayed when a menu for a residual image removal operation is selected according to an embodiment of the present invention.

4 is a flowchart of a residual image removal operation according to another embodiment of the present invention;

5 is a flowchart of a residual image removal operation according to another embodiment of the present invention;

6 is a diagram illustrating a screen displayed when an afterimage-free image is extracted according to an embodiment of the present invention; 7 is a diagram illustrating a screen displayed in the afterimage removal operation according to an embodiment of the present invention.

Claims (16)

A step of receiving a residual image removal mode request signal; Determining a luminance of an image to be displayed according to the received signal; And displaying at least one image in at least a region for the predetermined time with the determined brightness, Wherein the step of verifying the brightness of the image comprises performing gray scaling to extract a gray tone of brightness close to the brightness of an image displayed on the screen. The method according to claim 1, wherein the afterimage mode is performed when an arbitrary image is converted into a second image and displayed. The method according to claim 1, wherein the afterimage mode is performed every predetermined period when an arbitrary image is displayed as a still image for a predetermined time. delete The method according to claim 1, wherein the gray scale image is displayed on the OSD screen when the gray scaling is performed. The method according to claim 1, wherein the grayscaling is performed by displaying an image according to grayscaling on a screen and extracting a selected gray-toned luminance according to a user's input signal. The method according to claim 1, wherein the at least one image is a mosaic-type afterimage-removing image.  8. The image display device according to claim 7, wherein the pixels displaying the image after-image removal for a predetermined time display the original image, and the pixels displaying the original image are switched to the afterimage- Removal method. 9. The method of claim 8, wherein the afterimage-removing image is a blending image corresponding to the extracted brightness. A video display device comprising: A display unit for displaying an image and displaying an afterimage-free image with respect to the image; An image signal processing unit for extracting a luminance value for an image displayed on the display unit and performing gray scaling on the luminance value; And a controller for controlling the display unit to perform grayscaling according to the brightness extracted by the video signal processor and to display an afterimage-free image of the brightness value extracted through the gray scaling. Device. 11. The apparatus of claim 10, wherein the control unit Wherein the control unit controls the display unit to display an afterimage-free image of luminance extracted through grayscaling according to the luminance of the second image at the time of switching from the first image to the second image. 11. The apparatus of claim 10, wherein the control unit And controls to display at least one image in at least a partial region for a predetermined period of time when controlling to display the afterimage-removed image. 11. The apparatus of claim 10, wherein the control unit Wherein the control unit controls the display unit to perform a Blending process and display the gray tone according to the extracted brightness. The apparatus of claim 10, wherein the afterimage-free image is a mosaic-type image. 11. The apparatus of claim 10, wherein the control unit And controls the display unit to display an image according to gray scaling on an OSD screen when the gray scaling is performed. 11. The apparatus of claim 10, wherein the control unit Wherein the pixels displaying the image afterglow for a predetermined time display the original image and the pixels displaying the original image are switched to the afterimage-free image for display.

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