KR20070070328A - Filter substrate with a function of preventing the color shift and liquid crystal panel and display using the same - Google Patents

Abstract

A color filter substrate, and a liquid crystal panel and a liquid crystal display device using the same are provided to prevent crosstalk and color shift by equally distributing a voltage overcharged in a liquid crystal driving cell placed at the center of a pixel filter, to red, green, and blue sub pixels even if liquid crystal driving cells of a lower glass substrate are driven in a dot and/or line inversion method, and thus balancing red, green, and blue colors in horizontal and vertical line units. A color filter substrate(20) has a transparent substrate having pixel areas defined in a matrix shape, and red, green, and blue pixel filters(22) formed at each pixel area, to be arranged differently from adjacent pixel areas. The red, green, and blue pixel filters are arranged to be alternately located at the center according as the pixel areas move to the right and a lower position. A liquid crystal display device includes the color filter substrate, a data driver for driving data lines on the liquid crystal panel, and a data aligner converting arrangement by pixels of red, green, and blue sub pixel data included in video signals to be supplied to the data driver.

Description

Color Filter Substrate with Color Shift Prevention Function and Filter Substrate with a Function of Preventing the Color Shift and Liquid Crystal Panel and Display using the same}

In order to better understand the drawings used in the detailed description of the invention, a brief description of each drawing is provided.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure explaining the arrangement | positioning of the color filter in a normal color filter substrate.

2 is an exploded perspective view schematically illustrating a liquid crystal panel including a color filter substrate according to an exemplary embodiment of the present invention.

3 is an exploded perspective view schematically illustrating a liquid crystal panel including a color filter substrate according to another exemplary embodiment of the present disclosure.

4 is a block diagram schematically illustrating a driving circuit for driving a liquid crystal panel including a color filter substrate according to another exemplary embodiment of the present disclosure.

`` Explanation of symbols for main parts of drawings ''

10 lower glass substrate 12 liquid crystal drive cell

20: upper glass substrate 22: pixel filter

30: liquid crystal layer

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal panel in which an image is displayed in a liquid crystal display device, and more particularly, to a color filter substrate in which color filters are arranged.

Conventional liquid crystal display devices control the light transmittance of the liquid crystal so that an image is displayed. To this end, the liquid crystal display includes a liquid crystal panel including a liquid crystal layer and a panel driving circuit for driving the liquid crystal panel.

The liquid crystal panel includes a thin film transistor substrate for applying an electric field per unit region (ie, a pixel) to the liquid crystals of the liquid crystal layer. The thin film transistor substrate includes a plurality of pixel cells for applying an electric field to liquid crystal molecules in a unit region (pixel). Each of the pixel cells includes a pixel electrode corresponding to the unit region liquid crystal molecules and a thin film transistor for switching a driving voltage to be applied to the pixel electrode. In addition, the liquid crystal panel includes color filters for transmitting light of three primary colors to display a color image. The color filters may be formed on the thin film transistor substrate, but are typically installed on a separate glass substrate (hereinafter referred to as a "color filter substrate") corresponding to the thin film transistor substrate. In the color filter substrate, one pixel area is divided into three sub color pixel areas, and red, green, and blue filters are provided in these sub color pixel areas, respectively. Accordingly, each of the pixel cells of the thin film transistor substrate is configured of three sub color pixel cells. The color filters provided on the color filter substrate are arranged in the same shape in all pixel cells as shown in FIG. 1.

The panel driving circuit generates a driving voltage to be supplied to each sub color pixel cell in response to a color image signal (or image data) including color pixel signals (or pixel data) and supplies the driving voltage to each sub color pixel cell. do. In order to minimize power consumption, the panel driving circuit may have a voltage level of polarity in which driving voltages to be supplied to adjacent sub color pixel cells or driving voltages to be supplied to sub color pixel cells for each image are opposite to each other based on the common voltage Vcom. The liquid crystal panel is driven by an inversion system that has a. When the liquid crystal panel is driven in an inversion manner, only a driving voltage supplied to a sub color pixel cell positioned in the middle of three sub color pixel cells constituting one pixel is supplied to the sub color pixel cells positioned at both sides thereof. It has a voltage level of polarity opposite to the driving voltages. As a result, the sub color pixel cell in which the common voltage Vcom is located in the center is moved toward the level region of the polarity opposite to the driving voltage. The level shift effect of the common voltage Vco m causes the driving voltage applied to the center sub color pixel cell to be higher than the driving voltages applied to the sub color pixel cells positioned at both sides thereof.

The level shift phenomenon of the common voltage Vcom caused by the inversion panel driving circuit is a particular color bright or dark in a liquid crystal panel in which three sub color pixel cells constituting one pixel cell are arranged in the same order. Make it appear in the form of interference. This is because a particular sub color pixel cell (sub green pixel cell in Fig. 1) is driven by a higher driving voltage than sub color pixel cells adjacent thereto (sub red and blue pixel cells in Fig. 1). In this regard, there is a demand for a method capable of minimizing shift and interference of a specific color.

Accordingly, an object of the present invention is to provide a color filter substrate suitable for minimizing shift and interference of a specific color and a liquid crystal panel using the same.

Another object of the present invention is to provide a liquid crystal panel driving circuit and an inversion type liquid crystal display device suitable for minimizing shift and interference of a specific color.

According to an aspect of the present disclosure, a color filter substrate having a color change preventing function includes: a transparent substrate in which pixel regions are divided in a matrix form; And red, green, and blue filters formed in each of the pixel areas such that they are arranged differently from the pixel areas adjacent to each of the pixel areas.

Preferably, the red, green, and blue filters are arranged alternately in the center as the pixel region proceeds to the right and the bottom.

The red, green, and blue filters may be arranged to be cyclically shifted by one sub-pixel region in three sub-pixel regions constituting one pixel as the pixel region proceeds to the right and the bottom.

A liquid crystal panel according to another embodiment of the present invention includes the color filter substrate.

According to still another aspect of the present invention, there is provided a liquid crystal display device including: a liquid crystal panel including the color filter substrate; A data driver for driving data lines on the liquid crystal panel; And a data aligner for converting the pixel-by-pixel arrangement of the red, green, and blue sub-pixel data included in the video signal to be supplied to the data driver.

The data aligner preferably arranges the red, green, and blue sub-pixel data to be alternately positioned at the center as the pixel region proceeds to the right and the bottom.

The data aligner may be cyclically moved by one sub-pixel data for each pixel as the pixel region proceeds to the right and the bottom.

According to the above configuration, the color filter substrate according to the present invention balances red, green, and blue in the horizontal and vertical line units even though the liquid crystal cells are driven in a dot and / or line inversion scheme. Color Shift will not appear.

The color filter substrate may include a transparent substrate in which pixel regions are divided in a matrix form; And red, green, blue, and white filters arranged in a quadrangular shape formed in each of the pixel areas such that they are arranged differently from the pixel areas adjacent to each of the pixel areas.

It is preferable that the red, green, blue, and white filters are alternated with the diagonal bias as the pixel region proceeds to the right and the bottom.

The red, green, blue, and white filters may be arranged to be cyclically moved by one sub pixel area in a clockwise direction as the pixel area proceeds to the right and the bottom.

The liquid crystal display device includes a liquid crystal panel including the color filter substrate; A data driver for driving data lines on the liquid crystal panel; A data aligner may be provided to convert the pixel-by-pixel arrangement of the red, green, blue, and white sub-pixel data included in the video signal to be supplied to the data driver.

The data aligner arranges the red, green, blue, and white sub-pixel data alternately with the diagonal one by one as the pixel region proceeds to the right and the bottom.

The data aligner may be cyclically moved by one sub-pixel data for each pixel as the pixel region proceeds to the right and the bottom.

Other objects, other advantages, and other features of the present invention in addition to the above objects will become apparent from the detailed description of embodiments of the present invention in conjunction with the accompanying drawings.

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

2 is an exploded perspective view schematically illustrating a liquid crystal panel including a color filter substrate according to an exemplary embodiment of the present invention.

Referring to FIG. 2, the liquid crystal panel includes a liquid crystal layer 30 positioned between the lower glass substrate 10 and the upper glass substrate 20. The lower glass substrate 10 includes a liquid crystal driving cell 12 formed in each of the regions partitioned by m data lines DL1 through DLm and n gate lines GL1 through GLn. Each of the driving cells 12 adjusts the transmittance of the liquid crystal cell included in the liquid crystal layer 30 by the data signal from the data line DL in response to the scan signal from the gate line GL.

 The upper glass substrate 20, commonly referred to as a "color filter substrate", has pixel filters 22 to be arranged in matrix form. Each of the pixel filters 22 includes red, green, and blue sub-filters R, G, and B. These red, green, and blue sub-filters R, G, and B are circulated to the right (or left) by one sub-filter (i.e., one liquid crystal drive cell 12) according to the pixel filter 22. -Arranged in a moving form. The three color sub-filters R, G, and B included in the first pixel filter 22 on the first line are arranged in the order of red, green, and blue, and the second pixel filter 22 on the first line. The three color sub-filters R, G, and B included in are arranged in the order of blue, red, and green, and the three color sub-filters R, included in the third pixel filter 12 on the first line. G, B) are arranged in the order of green, blue and red. Whenever the position of the pixel filter 22 is moved in the horizontal direction as described above, the three color sub-filters R, G, and B are circulated by one color sub-filter (ie, one liquid crystal driving cell). It is arranged to move. Similarly, the three color sub-filters R, G, and B included in the first pixel filter 22 on the first line are arranged in the order of red, green, and blue, and the first pixel filter on the second line ( The three color sub-filters R, G, and B included in 22 are arranged in the order of blue, red, and green, and the three color sub-filters included in the first pixel filter 22 on the third line. R, G, and B) are arranged in the order of green, blue and red. Whenever the position of the pixel filter 22 is moved in the vertical direction as described above, the three color subfilters R, G, and B are circulated by one color subfilter (that is, one liquid crystal driving cell). It is arranged in a moving form. In other words, the red, green, and blue sub-filters R, G, and B which constitute one pixel filter 22 are each positioned horizontally by one pixel cell in the position of the pixel filter 22 (that is, the pixel). As they are moved in the vertical direction, they are alternately positioned in the pixel filter 22. Accordingly, even when the liquid crystal driving cells 12 on the lower glass substrate 10 are driven in a dot and / or line inversion scheme, a voltage that is overcharged by the liquid crystal driving cells 12 positioned in the center of one pixel filter 22 is centered. The red, green, and blue sub pixel cells are evenly distributed. As a result, red, green, and blue are balanced in horizontal and vertical lines so that crosstalk and color shift do not appear.

3 is an exploded perspective view schematically illustrating a liquid crystal panel including a color filter substrate according to another exemplary embodiment of the present disclosure.

The liquid crystal panel of FIG. 3 consists of red, green, blue and white sub-filters arranged such that each of the pixel filters 22 on the color filter substrate 20 is square and the liquid crystal cells on the lower glass substrate 10. 12 has the same structure as the liquid crystal panel of FIG. 2 except that four are arranged so as to form a square to form one pixel. Components of FIG. 3 having the same configuration, function and name as those in FIG. 2 will be referred to by the same reference numerals in FIG. 2.

The red, green, blue, and white sub-filters R, G, B, and W are arranged in such a manner as to be replaced with the diagonal sub-filters according to the pixel filter 22. The four color sub-filters R, G, B, and W included in the first pixel filter 22 on the first line are arranged in the order of red, green, blue, and white in the clockwise direction, and on the first line. The four color sub-filters R, G, B, and W included in the second pixel filter 22 are clockwise in the order of blue, white, red and green, and the third pixel filter on the first line ( The four color sub-filters R, G, B, and W included in 22 are arranged in the order of red, green, blue, and white in the clockwise direction. As described above, whenever the position of the pixel filter 22 is moved in the horizontal direction, the four color sub-filters R, G, B, and W are arranged in the form of swapping positions with the color sub-filter on the diagonal. Similarly, the four color sub-filters R, G, B, and W included in the first pixel filter 22 on the first line are arranged in the order of red, green, blue, and white in the clockwise direction, and the second The four color sub-filters R, G, B, and W included in the first pixel filter 22 on the line are in the order of blue, white, red and green clockwise, and the first pixel on the third line. The four color sub-filters R, G, B, and W included in the filter 22 are arranged in the order of red, green, blue, and red in the clockwise direction. Whenever the position of the pixel filter 22 is moved in the vertical direction as described above, the four color subfilters R, G, B, and W are disposed with the diagonal color subfilter (ie, one liquid crystal driving cell). Are arranged in the form of interchangeable. In other words, the red, green, blue, and white sub-filters R, G, B, and W forming one pixel filter 22 are each positioned at one pixel filter 22 (ie, pixel). As the cells are moved in the horizontal or vertical direction by the cell, the positions of the color sub-filters on the diagonal side are changed in the pixel filter 22. Accordingly, even when the liquid crystal driving cells 12 on the lower glass substrate 10 are driven in a dot and / or line inversion scheme, a voltage that is overcharged by the liquid crystal driving cells 12 positioned in the center of one pixel filter 22 is centered. The red, green, blue, and white sub pixel cells are evenly distributed. As a result, red, green, blue, and white are balanced in horizontal and vertical lines so that crosstalk and color shift do not appear.

Alternatively, the four color sub-filters R, G, B, and W are cycle-shifted by one color sub-filter in the clockwise direction as the pixel filter 22 is moved by one pixel in the horizontal and vertical directions. May be Even though the liquid crystal driving cells 12 on the liquid crystal panel having the color filter substrate 20 are driven in a dot and / or line inversion scheme, the liquid crystal driving cells 12 located in the center of one pixel filter 22 are overcharged. The voltage to be distributed is equally distributed to the red, green, blue, and white sub pixel cells. This results in a balance of red, green, blue, and white across the horizontal and vertical lines, resulting in no crosstalk and color shift.

4 is a block diagram illustrating a driving circuit for driving a liquid crystal panel including a color filter substrate according to the present invention.

The liquid crystal panel driving circuit of FIG. 4 sequentially-drives the data driver 110 driving the data lines DL1 to DLm of the liquid crystal panel 100 and the gate lines GL1 to GLn on the liquid crystal panel 100. And a data alignment unit 130 for rearranging video data to be supplied to the gate driver 120 and the data driver 110. In the liquid crystal panel 100, the sub pixel cells 102 connected to the gate line GL and the data line DL are arranged in a matrix form. These sub pixel cells 102 are positioned to correspond to the color sub filters R, G and B in FIG. 2 or the color sub filters R, G, B and W in FIG. Each of the sub pixel cells 102 is a data signal to be supplied from the data line DL to the liquid crystal cell CLC in response to a scan signal on the liquid crystal cell CLC and the gate line GL connected to the common voltage line Vcom. It consists of a thin film transistor (MT) for switching the. In other words, the sub pixel cell 102 corresponds to the equivalent circuit of the liquid crystal drive cell 12 in FIGS. 2 and 3. The gate driver 120 generates a scan signal for sequentially enabling the gate lines GL1 to GLn on the liquid crystal panel 100. The data driver 110 supplies a data signal to each of the data lines DL1 to DLm whenever the gate line GL is enabled. Each of the data signals on the data lines DL1 to DLm has a voltage having a polarity opposite to that of the data signal on the adjacent data line when the liquid crystal panel 100 is driven in a dot inversion scheme. In addition, the data signals on the data lines DL1 to DLm have voltages of inverted polarities whenever the gate lines GL1 to GLn are changed when the liquid crystal panel 100 is driven in a line inversion scheme. . Furthermore, when the liquid crystal panel 100 is driven in a dot and line inversion scheme, each of the data signals on the data lines DL1 to DLm has a voltage having a polarity opposite to that of the data signals on the adjacent lines and the gate line. Each time this change occurs (i.e. each time the next adjacent gate line is enabled), it will have a voltage of opposite polarity.

The data aligning unit 130 changes the arrangement of the sub pixel data included in the video data to be supplied from the input line 131 toward the data driver 110 to an arrangement pattern required by the liquid crystal panel 100. The video data input through the input line 131 includes sub color pixel data having the same pattern as that in which the sub color filters R, G, and B are arranged as shown in FIG. 1. In other words, the video data on the input line 131 includes sub color data arranged in the order of red, green, and blue for each pixel. On the other hand, the liquid crystal panel 100 has the sub color filters R, G, and B on the left side (up) or as much as one sub color filter as compared to the sub color filters included in the adjacent pixel filters 22. It includes an upper glass substrate (color filter substrate) 20 as shown in FIG. 2 arranged to be moved to the right (bottom) (in other words, circulated by one sub color filter). In order to display the color image on the liquid crystal panel 100, the sub pixel data arranged in the same manner as the array pattern of the sub color filters R, G, and B on the upper glass substrate 20 shown in FIG. Included video data is required. Accordingly, the data alignment unit 110 rearranges the input video data in which the sub pixel data are arranged in the same order in all the pixels as shown in FIG. 1. The video data rearranged by the data aligning unit 130 includes three sub-pixel data included in one pixel (i.e., the same as the pattern in which the sub color filters on the upper glass substrate 20 in FIG. 2 are arranged). Red, green, and blue sub-pixel data) are cyclically-shifted by one sub-pixel (ie, by one sub-color filter) as the position of the pixel is shifted by one pixel to the right and downwards. It has an array pattern of sub pixel data arranged. With this rearranged video data, the data driver 110 may display red, green, and red color on the liquid crystal drive cells 102 on the liquid crystal panel 100 in the same manner as the arrangement baton of the sub color filters on the upper glass substrate 20 of FIG. 2. The blue sub pixel signal is applied. In addition, in order for the liquid crystal driving cells 102 on the liquid crystal panel 100 to be driven in a dot inversion or line inversion or dot and line inversion scheme, the data driver 110 has a polarity of voltage in the pixel driving cells in the horizontal direction. These alternating data signals, or data signals whose polarities of voltages are alternated in the pixel driving cells 102 in the horizontal direction, or data signals whose polarities of voltages are alternated in the pixel driving cells 102 in the horizontal and vertical directions, The data lines DL1 through DLm on the liquid crystal panel 100 may be supplied.

Thus, the red, green, and blue sub pixels constituting one color pixel are arranged to be cyclically-shifted by one sub pixel according to the position of the pixel in the horizontal and / or vertical direction. In other words, the red, green, and blue sub pixels are alternately centered as the pixel positions are changed in the horizontal and / or vertical directions. Accordingly, even when the liquid crystal panel 100 is driven in a dot and / or line inversion scheme, a voltage that is overcharged in the center subpixel in each pixel is biased in any one of red, green, and blue pixels in horizontal and vertical line units. It is not evenly distributed. As a result, interference and color shift phenomenon do not occur in the image displayed on the liquid crystal panel, and a high quality color image can be displayed.

Alternatively, if the video data input through the input line 131 includes sub pixel data arranged in the order of red, white, green and blue, the video data is on the upper glass substrate 20 shown in FIG. The color image may be displayed on the liquid crystal panel 100 only by rearranging in the same manner as the arrangement pattern of the sub color filters R, G, B, and W. FIG. Accordingly, the data alignment unit 110 rearranges the video data in which the sub pixel data arranged in the order of red, white, green, blue, and white are arranged in the same order in all pixels. The video data rearranged by the data aligning unit 130 includes four sub-pixel data included in one pixel (i.e., the same as the pattern in which the sub color filters on the upper glass substrate 20 in FIG. 3 are arranged). Arranged sub-pixel data in red, white, green and blue order) are alternated with the arrangement of blue, green, white and red order as the position of the pixel is shifted by one pixel to the right and the downward direction. By the rearranged video data, the data driver 110 may display red, white, and white color on the liquid crystal driving cells 102 on the liquid crystal panel 100 in the same manner as the arrangement baton of the sub color filters on the upper glass substrate 20 of FIG. 3. Green and blue sub-pixel signals are applied. In addition, in order for the liquid crystal driving cells 102 on the liquid crystal panel 100 to be driven in a dot inversion or line inversion or dot and line inversion scheme, the data driver 110 has a polarity of voltage in the pixel driving cells in the horizontal direction. These alternating data signals, or data signals whose polarities of voltages are alternated in the pixel driving cells 102 in the horizontal direction, or data signals whose polarities of voltages are alternated in the pixel driving cells 102 in the horizontal and vertical directions, The data lines DL1 through DLm on the liquid crystal panel 100 may be supplied.

In this way, the red, white, green, and blue subpixels constituting one color pixel are arranged in such a manner as to be replaced with the subpixels of the diagonal pieces according to the positions of the pixels in the horizontal and / or vertical directions. In other words, the red sub-pixels are replaced with the blue sub-pixels, and the white sub-pixels are replaced with the green sub-pixels as the pixel positions are changed in the horizontal and / or vertical directions. Accordingly, even if the liquid crystal driving cells 12 on the liquid crystal panel having the color filter substrate 20 of FIG. 3 are driven in a dot and / or line inversion scheme, the liquid crystal driving cells positioned in the center of one pixel filter 22 are arranged. The overcharged voltage at 12 is evenly distributed among the red, green, blue, and white sub pixel cells. This results in a balance of red, green, blue, and white across the horizontal and vertical lines, resulting in no crosstalk and color shift.

As described above, in the color filter substrate of the color change prevention function according to the embodiment of the present invention, the red, green, and blue sub-filters constituting one pixel filter are positioned by one pixel at a position of the pixel filter (that is, the pixel). As they move in the horizontal or vertical direction, they are alternately centered in the pixel filter. Accordingly, even when the liquid crystal driving cells on the lower glass substrate are driven in a dot and / or line inversion scheme, the voltages that are overcharged by the liquid crystal driving cells positioned in the center of one pixel filter are equal to the red, green, and blue subpixel cells. To be distributed. As a result, red, green, and blue are balanced in horizontal and vertical lines so that crosstalk and color shift do not appear.

In addition, whenever the position of the pixel filter is moved in the vertical direction, the four color sub-filters R, G, B, and W are arranged in the form of swapping positions with the diagonal color sub-filters. Accordingly, even when the liquid crystal driving cells 12 on the lower glass substrate 10 are driven in a dot and / or line inversion scheme, a voltage that is overcharged by the liquid crystal driving cells 12 positioned in the center of one pixel filter 22 is centered. The red, green, blue and white sub pixel cells are evenly distributed.

As described above, the present invention has been described with reference to the embodiments shown in the drawings, which are merely exemplary, and a person of ordinary skill in the art without departing from the spirit and scope of the present invention. It will be apparent that various modifications, changes, and equivalent other embodiments are possible.

Claims (14)

A transparent substrate in which pixel regions are divided in a matrix form; And And a red, green, and blue filter formed in each of the pixel regions such that the pixel regions are arranged differently from the pixel regions adjacent to each of the pixel regions. The method of claim 1, And the red, green, and blue filters are alternately arranged centrally as the pixel region advances to the right and downward. The method of claim 1, And the red, green, and blue filters are arranged to be cyclically shifted by one sub-pixel region in three sub-pixel regions constituting one pixel as the pixel region proceeds to the right and the bottom. A liquid crystal panel comprising the color filter substrate of claim 1. A liquid crystal panel comprising the color filter substrate of claim 1; A data driver for driving data lines on the liquid crystal panel; And a data aligner for converting pixel-by-pixel arrays of red, green, and blue sub-pixel data included in the video signal to be supplied to the data driver. The method of claim 5, And the data aligner arranges the red, green, and blue sub-pixel data alternately in the center for each pixel as the pixel region proceeds to the right and the bottom. The method of claim 5, And the data sorter moves the pixel region cyclically by one sub-pixel data as the pixel region moves to the right and the bottom. A transparent substrate in which pixel regions are divided in a matrix form; And A color filter substrate comprising red, green, blue, and white filters arranged in a quadrangular shape formed in each of the pixel areas such that they are arranged differently from the pixel areas adjacent to each of the pixel areas. . The method of claim 8, And the red, green, blue, and white filters alternate with the diagonal ones as the pixel region proceeds right and down. The method of claim 8, And the red, green, blue, and white filters are arranged to be cyclically moved by one sub pixel region in a clockwise direction as the pixel region proceeds to the right and the bottom. A liquid crystal panel comprising the color filter substrate of claim 8. A liquid crystal panel comprising the color filter substrate of claim 8; A data driver for driving data lines on the liquid crystal panel; And a data aligner for converting pixel-by-pixel arrangements of red, green, blue, and white sub-pixel data included in the video signal to be supplied to the data driver. The method of claim 12, And the data aligner is arranged such that the red, green, blue, and white sub-pixel data are alternately alternated with the diagonal one by one as the pixel region advances right and downward. The method of claim 12, And the data sorter moves the pixel region cyclically by one sub-pixel data as the pixel region moves to the right and the bottom.

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