JP2008020574A - Liquid crystal dual screen display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid crystal dual screen display device that eliminates horizontal crosstalk which are caused during dual screen display and shows excellent display picture quality. <P>SOLUTION: A signal processing circuit 10 used in the liquid crystal dual screen display device includes: a look-up data table LUT that stores correction data corresponding to changes in the luminance caused by the grayscale difference between pixels adjacent to each other in a horizontal direction, based on preliminarily obtained input data values; and a crosstalk correction block 12 that carries out the operation of data correction for the all pixel data when a first image data and a second image data are combined to generate a dual-screen data, the operation including acquiring a correction data from the look-up data table LUT on the basis of a current pixel data and its right-side pixel data and correcting the current pixel data on the basis of the correction data to obtain a corrected current pixel data. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a liquid crystal two-screen display device, and in particular, displays a plurality of images superimposed on one screen, provides a first image in a first observation area, and displays a second image in a second observation area. The present invention relates to a liquid crystal two-screen display device that can provide different images to a plurality of observers.

  Conventionally, a liquid crystal display device has been widely used as a display device mounted on a television receiver, an information device, or the like. On the other hand, with the recent diversification of information devices and the like, a plurality of images are displayed on a single screen, the first image is provided in the first observation area, and the second image is displayed in the second observation area. A liquid crystal two-screen display device that provides an image of the above is known (see Patent Document 1 below).

  Hereinafter, this conventional liquid crystal two-screen display device will be described with reference to the drawings. FIG. 8 is a cross-sectional view of a conventional liquid crystal two-screen display device. As shown in FIG. 8, in the liquid crystal two-screen display device 50 according to the conventional example, the first pixel column 51a for displaying the first image and the second pixel column 51b for displaying the second image are alternately arranged. A liquid crystal display panel 52 is provided. Here, the first and second pixel columns 51a and 51b are made up of pixels of a liquid crystal display device, for example. Further, a black matrix 53 is formed between the pixels of the first and second pixel columns 51a and 51b. A light shielding plate 54 made of metal or resin having a light shielding function is disposed above the liquid crystal display panel 52 via a transparent substrate such as a glass substrate having a thickness G (not shown). The light shielding plate 54 includes light shielding portions 55 and openings 56 that alternately extend in parallel to the first pixel row 51a and the second pixel row 51b.

  Next, a mechanism for realizing two-screen display by the liquid crystal two-screen display device 50 configured as described above will be described. As shown in FIG. 8, the first observation region A that is leftward from the position C in front of the liquid crystal display panel 52 that is separated from the surface of the light shielding plate 54 by the distance D passes through the opening 56 of the light shielding plate 54. A first image is provided from the first pixel column 51a. At this time, the second image of the second pixel row 51b is not provided to the first observation region A because it is blocked by the light blocking portion 55 of the light blocking plate 54.

On the other hand, a second image is provided from the second pixel row 51 b through the opening 56 of the light shielding plate 54 to the second observation region B that is separated from the position C in front of the liquid crystal display panel 52 in the right direction. At this time, the first image of the first pixel row 51 a is blocked by the light blocking portion 55 of the light blocking plate 54, and thus is not provided to the second observation region B. In this way, a two-screen display is performed in which the first image is provided in the first observation area A and the second image is provided in the second observation area B.
JP-A-2005-258016 (Claims, paragraphs [0026] to [0036], FIG. 1)

  For example, when the liquid crystal two-screen display device 50 is disposed between a driver seat and a passenger seat in an automobile, the liquid crystal two-screen display device 50 is provided between the driver seat and the passenger seat. Therefore, for example, an image of a car navigation device can be observed by a person in the driver's seat, and other images can be observed by a person in the passenger seat.

  However, it is generally known that when there is a large potential difference between adjacent pixels in the liquid crystal display panel, the luminance level changes due to the potential difference. In a liquid crystal two-screen display device, such a large potential difference often occurs between adjacent pixels during two-screen display, and appears as horizontal crosstalk during two-screen display. This phenomenon will be described with reference to FIG. FIG. 9A is a schematic diagram showing the left and right input images and an image at the time of two-screen display, and FIG. 9B is a diagram showing the luminance level for each pixel of the liquid crystal two-screen display device. 9 (a) and 9 (b), the first observation position (left side) is surrounded by a triangular frame, and the second observation position (right side) is surrounded by a square frame to represent the right side and The left side is distinguished.

  For example, as shown in FIG. 9A, when the left input image is composed of a central black box image and its surrounding halftone solid image, and the right input image is composed of a full halftone solid image, 2 When the screen is displayed, the left image is displayed as the input image, but crosstalk occurs on the right side, and an area where the luminance changes is observed at a position corresponding to the left black box image.

  The luminance level of each pixel at this time is as shown in FIG. That is, when displaying two screens, there is no change in the luminance level of each pixel in the same halftone solid area for both the left and right input images, but in the portion where the left input image is a black solid area, Since the difference between the voltage applied to the electrode and the voltage applied to the pixel electrode corresponding to the adjacent right side increases, the luminance of the right side pixel becomes an intermediate solid image as shown by the arrow in FIG. The brightness is pushed up from the corresponding brightness (it may be lowered depending on the image to be displayed), and the brightness changes in a shape similar to the black solid area on the left side in the right display area. This is horizontal crosstalk when displaying two screens.

  As a result of various studies to eliminate the horizontal crosstalk in such a liquid crystal two-screen display device, the inventors have experimentally obtained in advance the amount of change in luminance caused by each gradation difference between adjacent pixels. Create a correction data table, correct the current pixel data by obtaining the amount of change on the correction data table from the current pixel data and the pixel data to the right of the current pixel data at the time of two-screen synthesis. It has been found that by applying to pixel data, a horizontal crosstalk is eliminated and a liquid crystal two-screen display device with good display image quality can be obtained, and the present invention has been completed.

  That is, an object of the present invention is to provide a liquid crystal two-screen display device that eliminates horizontal crosstalk that occurs during two-screen display and has excellent display image quality.

In order to achieve the above object, the liquid crystal two-screen display device of the present invention comprises
A liquid crystal display panel in which a first pixel column displaying a first image and a second pixel column displaying a second image are alternately arranged via a black matrix; and above the liquid crystal display panel A light-shielding plate having a light-shielding portion and an opening that are arranged and alternately extend in parallel with the first pixel row and the second pixel row, and a signal processing circuit, and the first observation region includes the first In a liquid crystal two-screen display device that provides one image, provides the second image to a second observation region, and enables different images to be simultaneously observed for a plurality of observers,
The signal processing circuit includes:
A data table in which correction data corresponding to a luminance change amount caused by a gradation difference between pixels adjacent in the horizontal direction based on an input data value obtained in advance is stored;
When creating the two-screen data by combining the data of the first image and the data of the second image, correction data is obtained from the data table based on the current pixel data and the pixel data on the right side thereof, A crosstalk data correction block that performs a data correction operation on all pixel data to correct the current pixel data based on the correction data and obtain corrected current pixel data;
It is characterized by having.

  In the liquid crystal two-screen display device according to the present invention, the corrected current pixel data is obtained as a sum of the current pixel data and the correction data.

  In the liquid crystal two-screen display device according to the present invention, the correction data is set to 0 when the current pixel data is the rightmost data.

  In the liquid crystal two-screen display device according to the present invention, the data table is composed of a matrix of (maximum number of gradations / 2) × (maximum number of gradations / 2).

  In the liquid crystal two-screen display device according to the present invention, the maximum number of gradations is 64.

  According to the present invention, in the liquid crystal two-screen display device, correction data is obtained by interpolation when the current pixel data or the right-side pixel data is between adjacent data in the data table. It is characterized by being.

  According to the present invention, in the liquid crystal two-screen display device, the data table data is stored in an EEPROM (Electrically Erasable and Programmable Read Only Memory), and the crosstalk data correction is performed. The block is characterized in that when power is turned on, data is read from the EEPROM and developed into a lookup table.

  Further, the present invention is characterized in that, in the above-mentioned liquid crystal two-screen display device, the EEPROM always stores data excluding data at a position where the correction value is zero.

  According to the present invention, in the above-mentioned liquid crystal two-screen display device, the correction data is composed of 4 bits including a sign bit, and two correction data are stored in one address in the EEPROM. To do.

  By providing the above configuration, the present invention has the following excellent effects. That is, according to the liquid crystal two-screen display device of the present invention, when creating the two-screen data by combining the data of the first image and the data of the second image, the input data and its Since the amount of change in luminance due to the difference in gradation from the data on the right side is corrected, horizontal crosstalk will not appear even if the difference in gradation between adjacent pixels on the left and right is large, and the display image quality will be improved. A good liquid crystal two-screen display device can be obtained.

  Further, according to the liquid crystal two-screen display device of the present invention, the current pixel data after correction is obtained as the sum of the current pixel data and the correction data, so that the current pixel after correction can be performed at high speed by simple calculation. Data can be obtained, and a liquid crystal two-screen display device with smooth display and good display image quality can be obtained.

  Further, according to the liquid crystal two-screen display device of the present invention, when the current pixel data is the rightmost data, there is no image data corresponding to the right side, and therefore no horizontal crosstalk occurs. By setting 0 to 0, even the rightmost data can be appropriately processed without changing the correction algorithm of the present invention.

In addition, according to the liquid crystal two-screen display device of the present invention, the data table is configured in a matrix of (maximum number of gradations / 2) × (maximum number of gradations / 2), that is, every two gradations. Since the data table can be accessed at high speed, a liquid crystal two-screen display device with smooth display and good display image quality can be obtained. In this case, since a medium to small liquid crystal display panel often employs 2 ⁶ = 64 gradation display, a 32 × 32 matrix is sufficient.

  Further, according to the liquid crystal two-screen display device of the present invention, the data in the data table is every two gradations, so that the gradation data between them can be easily obtained by interpolation. In this case, a decimal point may occur, but even if the decimal point is truncated, the display image quality is not greatly affected. Further, according to the liquid crystal two-screen display device of the present invention, the data in the data table is stored in the EEPROM, so that even if the liquid crystal two-screen display device model is different, it is possible to easily prepare a data table corresponding to the model. In addition, since the actual calculation is performed based on the data developed in the lookup table of the crosstalk data correction block, high-speed calculation is possible.

  Further, according to the liquid crystal two-screen display device of the present invention, when the current pixel data is the same as the pixel data to the right of the current pixel data, the current pixel data has the maximum value (maximum gradation value) and the minimum value (minimum value). When the (gradation value) is taken, there is no need for correction (the correction value is 0), so it is not necessary to store the data in this case in the EEPROM, so an EEPROM with a smaller capacity is used. I will do it.

  In addition, according to the liquid crystal two-screen display device of the present invention, the absolute value of the correction data itself is smaller than the maximum gradation value of the liquid crystal display panel. Correction can be made such that horizontal crosstalk does not appear sufficiently with correction data as small as 4 bits including bits, and a normal EEPROM can store 8-bit data at one address. Two correction data can be stored at one address. Therefore, it is only necessary to use an EEPROM having a small capacity.

  Hereinafter, the best embodiment of the present invention will be described with reference to the drawings. However, the embodiments described below exemplify a liquid crystal two-screen display device for embodying the technical idea of the present invention, and are not intended to specify the present invention. The present invention can be equally applied to other embodiments included in the scope. Further, the configuration other than the signal processing circuit of the liquid crystal two-screen display device of the present invention is the same as that of the liquid crystal two-screen display device of the conventional example shown in FIG. And

  First, as shown in FIG. 1, the signal processing circuit 10 in the liquid crystal two-screen display device of the embodiment includes a two-screen rearrangement block 11, a crosstalk correction block 12, an EEPROM 13, and a liquid crystal display panel control block 14. I have. Among them, the two-screen rearrangement block 11 is a circuit that synthesizes a signal representing the first image and a signal representing the second image and outputs them to each other. The conventional two-screen liquid crystal screen shown in FIG. The liquid crystal display panel control block 14 is also used in the conventional liquid crystal display device. In this embodiment, 6-bit data (IR_C [5: 0], IG_C [5: 0], IB_C [5: 0]) is calculated for each of R, G, and B from the two-screen rearrangement block 11. Similarly, the operation block 18 outputs 6-bit data (IR_ES [5: 0], IG_ES [5 :) for each of R, G, and B from the crosstalk correction block 12. 0], IB_ES [5: 0])) A total of 18-bit data is output, and a liquid crystal display panel (not shown) is driven based on this data.

  The crosstalk correction block 12 includes a preprocessing block 16, a correction data transmission block 17 including a look-up table (LUT) and a data complement block, and a calculation block 18. Among these, the preprocessing block 16 sends the current pixel data as it is to the correction data sending block 17 and the calculation block 18, and the next adjacent pixel data corresponding to the data on the right side of the current pixel data is sent to the correction data sending block 17. To be sent to. Then, in the correction data sending block 17, the correction data stored in the EEPROM 13 is read into the lookup table LUT at the same time when the power switch is turned on, and the tone value data of the current pixel and the tone value data of the adjacent pixels are read. Corresponding correction data is read from the lookup table LUT, the correction data is supplemented in the data complementing block as necessary, and the correction data read from the lookup table LUT or interpolated correction data is sent to the calculation block 18. It is made like that.

  The arithmetic block 18 obtains the corrected current pixel data by adding the current pixel data sent from the preprocessing block 16 and the correction data sent from the correction data sending block 17, and this correction is performed. The subsequent current pixel data is sent to the liquid crystal display panel control block 14. Such correction of current data is sequentially performed on all pixel data.

  Here, the lookup table LUT will be described with reference to FIG. This look-up table LUT assumes that both the current pixel data and the right-side pixel data are represented by, for example, 64 gradations (0 to 63), and each data corresponds to every two gradations (64/2). In addition to a matrix of × (64/2) = 32 × 32, a matrix of 33 × 33 is used so that 63 correction data, which is the maximum value at 64 gradations, can be stored. This is because if the lookup table LUT has only a 32 × 32 matrix corresponding to every two gradations, the maximum value is 62, and there is no correction data for 63 which is the maximum value at 64 gradations. Because it will be. Therefore, by making the lookup table LUT a 33 × 33 matrix and storing the correction data for 63 in the 33rd matrix, there is no need to separately calculate the 63 correction data in the circuit, and the look-up table LUT The calculation can be facilitated by preparing it in the uptable LUT. In particular, in the portion where the gradation is 63, the correction data often has a maximum value or a minimum value, and it is difficult to calculate the correction data separately in a circuit. Further, data between two gradations can be calculated by the method described below, but it is not easy to calculate the portion 63. Accordingly, it is very effective to prepare 63 correction data in the lookup table LUT in advance.

  In each matrix, correction data experimentally determined from the current pixel data and the right-side pixel data is, for example, 4-bit data. For example, as shown in Table 1 below, bit 3 is a sign bit. And 3 bits from bit 2 to bit 0 are used as correction data, and correction data from −7 to 0 to +7 are stored. As described above, the reason why the 4-bit data including the correction data sign bit is small is that the correction data is smaller than the maximum gradation value of the liquid crystal display panel, so that even if the gradation difference between the adjacent pixels on the left and right is large. This is because correction can be made so that horizontal crosstalk does not appear sufficiently with correction data as small as 4 bits including the sign bit.

  However, in FIG. 2, the portion where the code “0” is entered is a portion where the current pixel data and the right-side pixel data have the same value and horizontal crosstalk does not occur, and therefore no correction is necessary. The current data is the minimum value “0” or the maximum value “63”, and horizontal crosstalk does not occur regardless of the pixel data on the right side. In FIG. 2, all the correction data other than those that do not require correction because the horizontal crosstalk described above does not occur is omitted, but an integer value of −7 to 0 to +7 is entered.

  The EEPROM 13 stores data excluding the portion of the code “0” entered in FIG. 2, that is, (33 × 33−33 × 3 + 2) × 4 bits = 992 × 4 bits. The data determined experimentally in advance and stored in the EEPROM 13 is read from the EEPROM 13 into the look-up table LUT composed of the random access memory RAM when the power switch is turned on, as shown in FIG. Expanded to

  Next, correction data stored in the EEPROM 13 will be described with reference to FIG. FIG. 3 is a diagram showing the relationship between the address of the EEPROM 13 and the correction data stored at one address. In this example, the correction data of 992 × 4 bits described above stores two correction data at one address from addresses 0020h to 1FF0h. That is, the correction data is 4 bits including the sign bit, and 8 bits of data can be stored in one address of the EEPROM 13, so that bits 7 and 3 are sign bits, and bits 6 to 4 and bits 2 to 0 are respectively By using correction value data, two correction data can be stored at one address of the EEPROM 13.

  Further, the operation of the data complementing block of the correction data sending block 17 is as follows. That is, since the data developed in the lookup table LUT is data for every two gradations, the data between them can be obtained by interpolation. That is, when the data at the four positions in the Z portion in FIG. 2 are, for example, A, B, C, and D as shown in FIG. 4, if the correction data falls between A and B (A + B) / 2, when the correction data falls between A and C, the correction data is (A + C) / 2, and when the correction data falls between B and D, the correction data becomes C (B + D) / 2. Can be obtained as (C + D) / 2 if the correction data falls between D and D, and (A + B + C + D) / 4 if the correction data falls between A and D. The data for all gradations may be developed in the lookup table LUT. However, if such a configuration is adopted, the amount of data stored in the EEPROM 13 can be reduced, and the size of the lookup table LUT is small. Therefore, the lookup table LUT can be accessed at high speed, and the interpolation itself can be calculated easily and at high speed, so that a liquid crystal two-screen display device with smooth display and good display image quality can be obtained. In some cases, a decimal point may occur during interpolation, but even if the decimal point is discarded, the display image quality is not greatly affected.

  Next, a process of calculating correction data through the entire crosstalk correction block 12 will be described. The liquid crystal two-screen display device has 800 pixels in the horizontal direction, and displays each of the sub-pixels in the horizontal direction in turn as a left image and a right image, and displays an image composed of 400 pixels in each of the left image and the right image. It will be described as being. However, one pixel is composed of three sub-pixels of R, G, and B, and the number of pixels in the vertical direction is arbitrary. Further, in this embodiment, the data arrangement on the right side changes as shown in FIGS. 5 and 6 depending on the data writing direction of the liquid crystal display panel. FIG. 5 is a diagram showing the arrangement of output data from the crosstalk correction block 12 when the data writing direction of the liquid crystal display panel is from left to right, and FIG. 6 is the data writing direction of the liquid crystal display panel. It is a figure which shows the arrangement | sequence of the output data from the crosstalk correction block 12 in the case of going from right to left, and this state is selected by the HREV signal of FIG. Therefore, description will be made with reference to FIG. 7, which is a timing chart of input signals and output signals, divided into a case of writing from left to right in the order of RGB and a case of writing from right to left in the order of RGB.

  In the following, each color and position is represented by, for example, “Ra.b”, R, G, and B symbols representing colors, and a numerical value “a” indicating the line number of the liquid crystal display panel. , And a numerical value b indicating what number input or output of the color in the horizontal direction is displayed in combination, and the correction value is a, for example, “h (Ra.b, Ga.b)” The correction value obtained from the look-up table LUT is displayed based on the b-th red R input signal of the line and the b-th green G input signal of the right a line. In this case, since it is not necessary to consider vertical crosstalk in the present invention, all the values of a are the same on the same line, but the values of b may be the same or different.

[When writing from left to right]
When writing to the liquid crystal display panel from left to right in the order of RGB, it is selected by setting, for example, HREV = L. As shown in FIG. 7A and Table 2 below, the signals input from the two-screen rearrangement block 11 to the crosstalk correction block 12 are the data enable signal DE_C and the clock signal DCLK_C, and the signal on the first line is R , G, and B are input in parallel in the horizontal direction by 6 bits.

  These 6-bit signals IR_C [5: 0], IG_C [5: 0] and IB_C [5: 0] are rearranged by the preprocessing block 16 and input in the direction of the arrow shown in Table 3 below. 1 to input 800 are input in series to the correction data transmission block 17 and the calculation block 18 as current pixel data.

  In the correction data transmission block 17, correction data is sequentially selected based on the correction data developed in the lookup table LUT in the order of the input signals shown in Table 3. That is, if the first current input signal is R1.1, the signal on the right side is G1.1, so R1.1 and G1.1 are compared and looked up based on the tone values of both. Data in the table LUT is selected, and the value is sent to the calculation block 18 as 4-bit correction data h (R1.1, G1.1). In this way, correction values are sequentially selected from the lookup table LUT. Table 4 shows the correction data string of the first line in this case. Since there is no right data corresponding to B1.800 which is the rightmost data, the correction data corresponding to B1.800 is “0”. In this way, the same processing is performed for all data of one line.

  Then, the 4-bit correction data shown in Table 4 is serially input to the calculation block 18, and the sum with the current pixel data shown in Table 2 that is also input in series to the calculation block 18 is calculated. The obtained corrected current pixel data is rearranged by 6 bits for each of R, G, and B, and IR_ES [5: 0] and IG_ES [5 as shown in Table 5 and FIG. : 0] and IB_ES [5: 0] are input in parallel to the liquid crystal display panel control block 14.

  Thus, the corrected current pixel data IR_ES [5: 0], IG_ES [5: 0], and IB_ES [5: 0] obtained as described above are corrected to the liquid crystal display panel. It is sent to the display panel control block 14. Then, the same processing as in the case of the first line as described above was performed for all of the second line, the third line, etc., and writing to the liquid crystal display panel was performed to reduce horizontal crosstalk 2 A screen display is made. Here, it is usual that the current pixel data after correction is 6 bits × 3 = 18 bits of IR_ES [5: 0], IG_ES [5: 0], and IB_ES [5: 0]. This is because the liquid crystal display panel control block 14 used in the above can be directly processed.

[When writing from right to left]
When writing to the liquid crystal display panel from right to left in the order of RGB, it is selected by setting HREV = H. Also in this case, the signals IR_C [5: 0], IG_C [5: 0] and IB_C [5: 0] input from the two-screen rearrangement block 11 to the crosstalk correction block 12 are as shown in FIG. As shown in Table 2 above, the 6-bit signals IR_C [5: 0], IG_C [5: 0], and IB_C [5: 0] are rearranged in the preprocessing block 16, The current pixel data is input to the correction data transmission block 17 and the calculation block 18 in series in the direction of the arrow shown in Table 6 below and in the order of input 1 to input 800.

  Then, in the correction data transmission block 17, correction data is sequentially selected based on the correction data developed in the lookup table LUT in the order of the input signals shown in Table 6. That is, when the first current input signal is B1.1, there is no data corresponding to the right side thereof, so the correction data for B1.1 is “0”. Further, since the next input signal is G1.1, G1.1 is compared with B1.1 on the right side thereof, and the data of the lookup table LUT is selected based on the gradation value of both, and the value is It is sent to the calculation block 18 as 4-bit correction data h (G1.1, B1.1). In this way, correction values are sequentially selected from the lookup table LUT. Table 7 shows the correction data string of the first line in this case.

  Then, the 4-bit correction data shown in Table 7 is serially input to the calculation block 18, and the sum with the current pixel data shown in Table 6 which is also input in series to the calculation block 18 is calculated. The corrected current pixel data is rearranged by 6 bits for each of R, G, and B, and IR_ES [5: 0], IG_ES [5: 0], and IB_ES [5: 0] is input to the liquid crystal display panel control block 14.

  In this way, writing to the liquid crystal display panel is performed by using the obtained corrected current pixel data IR_ES [5: 0], IG_ES [5: 0], and IB_ES [5: 0], so that the horizontal cross Two-screen display with reduced talk is performed.

It is a block diagram of the processing circuit in the liquid crystal 2 screen display device of an example. It is the schematic which shows the data arrangement | positioning of the lookup table LUT. It is a figure which shows the relationship between the address of EEPROM, and the correction data stored in 1 address. It is a figure for demonstrating the data complement method in a data complement block. It is a figure which shows the arrangement | sequence of the output data from a crosstalk correction block in case the writing direction of the data of a liquid crystal display panel is from left to right. It is a figure which shows the arrangement | sequence of the output data from a crosstalk correction block in case the writing direction of the data of a liquid crystal display panel is right to left. It is a timing chart of an input signal and an output signal. It is sectional drawing of the liquid crystal 2 screen display apparatus which concerns on a prior art example. FIG. 9A is a schematic diagram showing the left and right input images and an image at the time of two-screen display, and FIG. 9B is a diagram showing the luminance level for each pixel of the liquid crystal two-screen display device. .

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Signal processing circuit 11 2 screen rearrangement block 12 Crosstalk correction block 13 EEPROM
14 Liquid crystal display panel control block 16 Preprocessing block 17 Correction data transmission block 18 Calculation block

Claims (9)

A liquid crystal display panel in which a first pixel column displaying a first image and a second pixel column displaying a second image are alternately arranged via a black matrix; and above the liquid crystal display panel A light-shielding plate having a light-shielding portion and an opening that are arranged and alternately extend in parallel with the first pixel row and the second pixel row, and a signal processing circuit, and the first observation region includes the first In a liquid crystal two-screen display device that provides one image, provides the second image to a second observation region, and enables different images to be simultaneously observed for a plurality of observers,
The signal processing circuit includes:
A data table in which correction data corresponding to a luminance change amount caused by a gradation difference between pixels adjacent in the horizontal direction based on an input data value obtained in advance is stored;
When creating the two-screen data by combining the data of the first image and the data of the second image, correction data is obtained from the data table based on the current pixel data and the pixel data on the right side thereof, A crosstalk data correction block that performs a data correction operation on all pixel data to correct the current pixel data based on the correction data and obtain corrected current pixel data;
A liquid crystal two-screen display device comprising:   2. The liquid crystal two-screen display device according to claim 1, wherein the corrected current pixel data is obtained as a sum of the current pixel data and the correction data.   2. The liquid crystal two-screen display device according to claim 1, wherein the correction data is set to 0 when the current pixel data is the rightmost data.   2. The liquid crystal two-screen display device according to claim 1, wherein the data table includes a matrix of (maximum number of gradations / 2) × (maximum number of gradations / 2).   The liquid crystal two-screen display device according to claim 4, wherein the maximum number of gradations is 64.   6. The correction data is obtained by interpolation when the current pixel data or pixel data on the right side thereof is between adjacent data in the data table. Liquid crystal two-screen display device.   2. The data of the data table is stored in an EEPROM, and the crosstalk data correction block reads data from the EEPROM when power is turned on and develops it in a lookup table. The liquid crystal two-screen display device described.   8. The liquid crystal two-screen display device according to claim 7, wherein the EEPROM always stores data excluding data at a position where the correction value is zero.   9. The liquid crystal two-screen display device according to claim 7, wherein the correction data is composed of 4 bits including a sign bit, and two correction data are stored in one address in the EEPROM. .

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