JP4957090B2 - Display device and video display device - Google Patents

Description

  The present invention relates to a display device and a video display device. Specifically, the present invention relates to a display device and a video display device that employ a method of writing video signals in parallel in a horizontal direction (column direction) with respect to a display unit in which pixels are arranged in a matrix.

A display device, for example, a liquid crystal display device (LCD; Li) using a liquid crystal cell as a display element of a pixel
In general, a method of writing video signals in parallel in a plurality of pixels in the horizontal direction is employed because the writing speed of a liquid crystal display is not fast enough to sequentially write an input video signal one dot (pixel) at a time. .

  FIG. 6 is a schematic diagram for explaining a conventional transmissive LCD employing a method of writing video signals in parallel in a plurality of pixels in the horizontal direction. The transmissive LCD shown here includes gate lines 201 arranged in the row direction. And a data line 202 arranged in the column direction, and a matrix-like liquid crystal pixel electrode 203 having a storage capacitor arranged at each intersection of the gate line and the data line, and N pixels in the horizontal direction are unit. Each unit unit is configured to write a video signal.

  Here, in the conventional transmissive LCD, the positional relationship between the data line and the liquid crystal pixel electrode is configured in common for all pixels. Specifically, all the liquid crystal pixel electrodes are always positioned on the left side of the data line, or all the liquid crystal pixel electrodes are always positioned on the right side of the data line (for example, patents). Reference 1).

JP 2003-43945 A

  However, if a video signal is supplied to the data line in the (N + 1) th unit unit in order to write to the liquid crystal pixel electrode in the (N + 1) (N: natural number) th unit unit, the inside of the (N + 1) th unit unit. Coupling capacitance is generated between the data line and the liquid crystal pixel electrode in the Nth unit unit, and this coupling capacitance contributes to variation in the holding potential of the liquid crystal pixel electrode.

Here, since the coupling capacitance increases as the distance between the liquid crystal pixel electrode and the data line decreases, the liquid crystal pixel in the first column of the (N + 1) th unit unit and the last column of the Nth unit unit. The coupling capacitance C _A (see FIG. 7) formed between the electrodes becomes the largest, and the final of the Nth unit unit caused by the potential fluctuation of the data line of the first column of the (N + 1) th unit unit. The variation in the holding potential of the liquid crystal pixel electrode in the column is the most remarkable. This phenomenon repeatedly occurs every time data is written to the unit unit, and also occurs for all vertical lines in the same manner. As a result, it is visually recognized as vertical stripes every unit unit over the entire screen. As a result, the image quality is degraded.

  In addition, in the LCD, when a DC voltage is applied to the liquid crystal, the liquid crystal component is decomposed, contamination due to impurities generated in the liquid crystal cell and liquid crystal image burn-in, etc. , An inversion driving method (a frame inversion method in which the polarity of the driving voltage is inverted for each frame, a line inversion method in which the polarity of the driving voltage is inverted for each line, etc.) for inverting the polarity of the driving voltage of the liquid crystal pixel electrode at a constant cycle However, when such an inversion driving method is adopted, the potential fluctuation amount of the data line becomes large, so the data line of the first column of the (N + 1) th unit unit and the Nth unit unit The coupling capacitance formed between the last column of liquid crystal pixel electrodes also increases, resulting in an increase in the amount of variation in the holding potential of the liquid crystal pixel electrodes.

  In addition, in the case of a transmissive LCD that employs a method of writing a video signal pixel by pixel, it is considered that all liquid crystal pixel electrodes are similarly affected by the coupling capacitance. Vertical stripes and the like that occur in a transmissive LCD that employs a writing method are not visible.

  The present invention has been made in view of the above points, and an object of the present invention is to provide a display device and a video display device that can suppress vertical stripes.

In order to achieve the above object, a display device according to the present invention includes a gate line arranged in a row direction, a data line arranged in a column direction, and each intersection where each gate line and each data line intersect. And a plurality of pixel electrodes connected to the left or right side of the data lines as a unit unit. has units unit 4 above, the display device writing the video signal is made for each of the basic units, in the odd-numbered of the unit unit, and the even-numbered of the unit unit, connected to said data lines and said data lines position relationship between the pixel electrode is inverted in the row direction.

In order to achieve the above object, a video display device according to the present invention includes a gate line arranged in a row direction, a data line arranged in a column direction, and each gate line and each data line intersect. and a matrix of pixel electrodes arranged at each intersection, the data lines and the unit a plurality of said pixel electrodes horizontally connected to either side of these data lines of a plurality successive rows in the row direction as a unit, has the basic units of 4 or more, including the display device writing the video signal is made for each of the basic units, the video display apparatus for performing image display using the light modulated by the display device, the odd th and the unit unit, in the even-numbered of the unit unit, the position relationship between the pixel electrode connected to the data lines and the data lines are inverted in the row direction.

  Here, the positional relationship between the data line of the last column of the nth (n: natural number) unit unit and the pixel electrode connected to the data line, and the data of the first column of the (n + 1) th unit unit. Since the positional relationship between the line and the pixel electrode connected to the data line is inverted, the pixel electrode of the last column of the nth unit unit and the first column of the (n + 1) th unit unit In order to increase the distance to the data line, a coupling capacitance formed between the pixel electrode of the last column of the nth unit unit and the data line of the first column of the (n + 1) th unit unit Can be reduced.

  In the display device and the video display device of the present invention, a coupling capacitor formed between the pixel electrode of the last column of the nth unit unit and the data line of the first column of the (n + 1) th unit unit is provided. Since the potential fluctuation of the pixel electrode connected to the data line of the last column of each unit unit can be suppressed, vertical stripes can be reduced.

Hereinafter, embodiments of the present invention will be described with reference to the drawings to facilitate understanding of the present invention.
FIG. 1 is a schematic view for explaining an active matrix drive type transmissive LCD as an example of an LCD to which the present invention is applied. The transmissive LCD shown here is similar to a conventional transmissive LCD in the row direction. A gate line 1 arranged in a row, a data line 2 arranged in a column direction, and a matrix-like liquid crystal pixel electrode 3 having a storage capacitor arranged at each intersection of the gate line and the data line, N pixels in the horizontal direction are set as unit units, and a video signal is written for each unit unit.
Further, in the odd-numbered unit units (hereinafter referred to as “odd units”), the data line is configured to be located on the left side of the liquid crystal pixel electrode, and the even-numbered unit units (hereinafter referred to as “even-number units”). The data line is configured to be located on the right side of the liquid crystal pixel electrode. That is, in the odd-numbered unit and the even-numbered unit, the positional relationship between the data line constituting one pixel and the liquid crystal pixel electrode is reversed.

Here, in this embodiment, the case where all the data lines of the odd-numbered units are located on the left side of the liquid crystal pixel electrode is described as an example. However, in the last column where the potential fluctuation of the liquid crystal pixel electrode is most remarkable. In order to reduce the coupling capacity of the liquid crystal pixel electrode, it is sufficient that at least the data line of the last column of the odd unit is located on the left side of the liquid crystal pixel electrode, and all the data lines of the odd unit are not necessarily the liquid crystal pixel electrode. There is no need to be on the left side of the.
Similarly, in the present embodiment, the case where all the data lines of the even-numbered units are located on the right side of the liquid crystal pixel electrode is described as an example. However, in the last column in which the potential fluctuation of the liquid crystal pixel electrode is most remarkable. In order to reduce the coupling capacity of the liquid crystal pixel electrode, it is sufficient that at least the data line of the last column of the even unit is located on the right side of the liquid crystal pixel electrode, and all the data lines of the even unit are not necessarily the liquid crystal pixel electrode. There is no need to be located on the right side of.

In the transmissive LCD to which the present invention described above is applied, the distance between the data line of the first column of the (N + 1) th unit unit and the liquid crystal pixel electrode of the last column of the Nth unit unit (indicated by reference numeral B in FIG. 2). Distance) is the distance between the data line of the first column of the (N + 1) th unit unit of the conventional transmissive LCD and the liquid crystal pixel electrode of the last column of the Nth unit unit (distance indicated by reference symbol A in FIG. 7). (See FIG. 2), the coupling capacitance C _B formed between the data line of the first column of the (N + 1) th unit unit and the liquid crystal pixel electrode of the last column of the Nth unit unit is to reduce than coupling capacitance C _a of the conventional transmission-type LCD, vertical stripe suppression is realized.

FIG. 3 is a schematic view for explaining an active matrix drive type transmissive LCD as another example of an LCD to which the present invention is applied. The transmissive LCD shown here is a conventional transmissive LCD and the above-described book. As in the case of the transmissive LCD to which the invention is applied, the gate lines 1 arranged in the row direction, the data lines 2 arranged in the column direction, and the storage capacitors arranged at the intersections of the gate lines and the data lines A matrix-like liquid crystal pixel electrode 3 is provided, and N pixels in the horizontal direction are set as unit units, and a video signal is written for each unit unit.
In the odd unit, the data line is configured to be positioned on the right side of the liquid crystal pixel electrode, and in the even unit, the data line is configured to be positioned on the left side of the liquid crystal pixel electrode. That is, in the odd-numbered unit and the even-numbered unit, the positional relationship between the data line constituting one pixel and the liquid crystal pixel electrode is reversed.

Here, in this embodiment, the case where all the data lines of the odd-numbered units are located on the right side of the liquid crystal pixel electrode is described as an example. However, in the last column in which the potential fluctuation of the liquid crystal pixel electrode is most remarkable. In order to reduce the coupling capacity of the liquid crystal pixel electrode, it is sufficient that at least the data line of the last column of the odd unit is located on the right side of the liquid crystal pixel electrode, and all the data lines of the odd unit are not necessarily the liquid crystal pixel electrode. There is no need to be located on the right side of.
Similarly, in this embodiment, the case where all the data lines of the even-numbered unit are located on the left side of the liquid crystal pixel electrode is described as an example. However, in the last column where the potential fluctuation of the liquid crystal pixel electrode is most remarkable. In order to reduce the coupling capacity of the liquid crystal pixel electrode, it is sufficient that at least the data line of the last column of the even unit is located on the left side of the liquid crystal pixel electrode, and all the data lines of the even unit are not necessarily the liquid crystal pixel electrode. There is no need to be on the left side of the.

In the transmissive LCD to which the present invention described above is applied, the distance between the data line of the first column of the (N + 1) th unit unit and the liquid crystal pixel electrode of the last column of the Nth unit unit (indicated by reference numeral C in FIG. 4). Distance) is the distance between the data line of the first column of the (N + 1) th unit unit of the conventional transmissive LCD and the liquid crystal pixel electrode of the last column of the Nth unit unit (distance indicated by reference symbol A in FIG. 7). (See FIG. 4), the coupling capacitance C _c formed between the data line of the first column of the (N + 1) th unit unit and the liquid crystal pixel electrode of the last column of the Nth unit unit is to reduce than coupling capacitance C _a of the conventional transmission-type LCD, vertical stripe suppression is realized.

  FIG. 5 is a schematic diagram for explaining a transmissive liquid crystal projector which is an example of an image display device to which the present invention is applied. The transmissive liquid crystal projector 100 shown here is a so-called three-plate system that has red, green and blue colors. This is a projection type image display device that uses the transmissive LCD shown in FIG. 1 or 3 for three light valves corresponding to the three primary colors and displays a color image enlarged and projected on a screen (not shown).

  Specifically, the transmissive liquid crystal projector includes a lamp 101 that is a light source that emits illumination light, an R dichroic mirror 103R that reflects only red light (R) among illumination light from the lamp, and illumination light from the lamp. Among them, a G dichroic mirror 103G that reflects only green light (G), and an R light valve 104R that is a light modulation means that modulates and transmits red light (R), green light (G), and blue light (B). , G light valve 104G and B light valve 104B, dichroic prism 105 which is a combining optical means for combining modulated red light (R), green light (G), and blue light (B), and combined illumination light And a projection lens 106 which is a projection means for projecting the image onto the screen.

  Here, the lamp emits white light including red light (R), green light (G), and blue light (B), and includes, for example, a halogen lamp, a metal halide lamp, a xenon lamp, or the like.

  Further, in the optical path between the lamp and the R dichroic mirror, a filter 109 that cuts infrared rays and ultraviolet rays, a fly-eye lens 107 that equalizes the illuminance distribution of the illumination light emitted from the lamp, and the P of the illumination light , A polarization conversion element 108 for converting the S polarization component into one polarization component (for example, S polarization component) is disposed.

  The projection lens has a function of enlarging and projecting light from the dichroic prism toward the screen.

  In the transmissive liquid crystal projector configured as described above, white light emitted from the lamp is separated into red light (R), green light (G), and blue light (B) by the R dichroic mirror and the G dichroic mirror. . The separated red light (R), green light (G), and blue light (B) are incident on each light valve via the condenser lens 112. Red light (R), green light (G), and blue light (B) incident on each light valve are subjected to polarization modulation in accordance with a driving voltage applied to each pixel of each light valve, and then are dichroic prism. The synthesized light is enlarged and projected on the screen by the projection lens.

  As described above, in this transmissive liquid crystal projector, a color image is displayed by enlarging and projecting an image corresponding to the light modulated by the light valve on the screen.

  By the way, since the transmissive LCDs constituting each light valve can suppress vertical stripes as described above, the reliability of display quality can be improved even in the transmissive projector shown here.

  In this embodiment, a projection type image display device that projects onto a screen like a transmission type projector has been described as an example. However, the present invention is a direct view type image display device that directly sees a transmission type LCD. Also widely applicable.

It is a schematic diagram for demonstrating the transmissive LCD of the active matrix drive system which is an example of LCD applied with this invention. FIG. 2 is a schematic diagram for explaining a distance between a data line of the first column of the (N + 1) th unit unit of the transmissive LCD shown in FIG. 1 and a liquid crystal pixel electrode of the last column of the Nth unit unit. It is a schematic diagram for demonstrating the transmissive LCD of the active matrix drive system which is another example of LCD applied with this invention. FIG. 4 is a schematic diagram for explaining the distance between the data line of the first column of the (N + 1) th unit unit of the transmissive LCD shown in FIG. 3 and the liquid crystal pixel electrode of the last column of the Nth unit unit. It is a schematic diagram for demonstrating the transmissive liquid crystal projector which is an example of the video display apparatus to which this invention is applied. It is a schematic diagram for demonstrating the conventional transmissive LCD. FIG. 7 is a schematic diagram for explaining the distance between the data line of the first column of the (N + 1) th unit unit of the transmissive LCD shown in FIG. 6 and the liquid crystal pixel electrode of the last column of the Nth unit unit.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Gate line 2 Data line 3 Liquid crystal pixel electrode 100 Transmission type liquid crystal projector 101 Lamp 103R R dichroic mirror 103G G dichroic mirror 104R R light valve 104G G light valve 104B B light valve 105 Dichroic prism 106 Projection lens 107 Fly eye lens 108 Polarization conversion Element 109 Filter 110 Total reflection mirror 111 Relay lens 112 Condenser lens

Claims (4)

A gate line arranged in the row direction, a data line arranged in the column direction, and a matrix-like pixel electrode arranged at each intersection where each gate line and each data line intersect, and continuous in the row direction a plurality of rows the data lines and a plurality of said pixel electrodes horizontally connected to either side of these data lines as a unit units has the unit unit 4 above, writing of the video signal for each of the unitary units In a display device in which
Display of the odd-numbered of the unit unit, in the even-numbered of the unit unit, characterized in that the position relationship between the pixel electrode connected to said data lines and said data lines is inverted in the row direction apparatus. The data lines of the odd-numbered unit units are positioned on the left side of the pixel electrodes connected to the data lines, and the data lines of the even-numbered unit units are connected to the data electrodes. The display device according to claim 1, wherein the display device is located on the right side. The data lines of the odd-numbered unit units are positioned on the right side of the pixel electrodes connected to the data lines, and the data lines of the even-numbered unit units are connected to the data electrodes. The display device according to claim 1, wherein the display device is located on the left side. It has gate lines arranged in the row direction, data lines arranged in the column direction, and matrix-like pixel electrodes arranged in each intersection where each gate line and each data line intersect, and in the row direction a plurality of said pixel electrodes horizontally connected to either side of the data lines and these data lines successive plurality of columns as basic units has the unit unit 4 above, the video signal for each of the unitary units In a video display device comprising a display device to which writing is performed, and performing video display using light modulated by the display device,
Image of the odd-numbered of the unit unit, in the even-numbered of the unit unit, characterized in that the position relationship between the pixel electrode connected to said data lines and said data lines is inverted in the row direction Display device.

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