JPH0644122B2 - Liquid crystal display element - Google Patents

Description

TECHNICAL FIELD The present invention relates to a liquid crystal display device in which unit cells corresponding to picture elements are arranged in a matrix.

(Prior Art) In recent years, the liquid crystal display element has advantages such as thinness, low power driving, and low power consumption, and thus the market needs as a flat display are rapidly increasing.

In the display unit of a normal liquid crystal display element, picture elements for displaying characters, images, etc. are arranged in a matrix in the X and Y directions.

However, under the present circumstances, since the number of picture elements cannot be increased as much as a CRT, in a simple vertical, horizontal, or diagonal arrangement, a stripe irrelevant to the display content is recognized, so that the display quality is deteriorated.

In order to improve this, for example, Japanese Patent Laid-Open No. 59-9636 discloses a liquid crystal display element in which picture elements are arranged row by row in the X direction or column by column in the Y direction by shifting the matrix pitch by a half pitch. Proposed.

Generally, a unit cell corresponding to a picture element is divided into a light transmitting region and a light non-transmitting region. FIG. 2 is a plan view of a unit cell corresponding to a picture element of a liquid crystal display element, in which 10 indicates a light transmitting region and 20 indicates a light non-transmitting region.

Especially, this is TFT (thin film transistor) or MIM.
It corresponds to a liquid crystal display element that drives liquid crystal with a non-linear element such as (metal-insulating film-metal), and the wiring portion such as the scanning line and the data line or the non-linear element portion becomes the light opaque region 20,
Other than that is the light transmission region 10 through which light actually passes.

For this reason, the symmetry of the light transmitting region is not always maintained.

FIG. 3 particularly shows an arrangement by unit cells in which the above-mentioned symmetry is not maintained, and in each cell, the light transmission region is arbitrary at least parallel to the Y direction (for example, the signal line direction). , Which are not symmetric with respect to the straight line, have the light transmitting regions of the picture elements in the same row in the same direction and have the same shape.
Has an inverted shape with respect to the axis and is arranged with the matrix pitch shifted by a half pitch between rows.

(Problems to be Solved by the Invention) However, in the matrix arrangement as shown in FIG. 3 in which the unit cells are simply shifted by a half pitch for each row, the light opaque regions of the unit cells are distributed in the display portion. However, it is impossible to completely eliminate an unnatural pattern (moiré pattern) such as stripes unrelated to the content to be displayed, which causes a problem that the display quality is significantly deteriorated. The same applies to a matrix arrangement in which each row is shifted by a half pitch. The above-mentioned problems occur in that the light transmission region does not occupy most of the unit cell, and furthermore, the unit cell has an asymmetrical shape in both the X direction and the Y direction. Therefore, the optical center of gravity in the unit cell does not match the center of gravity of the unit cell. That is, in the entire liquid crystal display element, the optical center of gravity of each unit cell is unbalanced, and the picture elements are not evenly arranged.

The present invention does not simply shift the relative arrangement of the matrix-arranged picture elements of the display section of the liquid crystal display element by a half pitch,
It is another object of the present invention to provide a liquid crystal display device having an improved display quality by optimizing the shifting method.

(Means for Solving the Problems) In order to achieve the above object, the present invention provides a unit cell corresponding to a picture element including a light transmission region and a light non-transmission region in which the unit cells are orthogonal to each other in the scanning line direction (X direction, Row direction), signal line direction (Y direction,
In the cells, the light transmission regions are not symmetrical with respect to at least any straight line parallel to the signal line direction, and the pixels of the same row are arranged in a matrix at a predetermined repeating pitch in the column direction). The light transmitting areas have the same shape in the same direction,
The light transmission areas of the picture elements in the rows adjacent to each other have an inverted shape with the signal line direction as an axis, and divide the area of the light transmission area of a unit cell in the i-th row into two equal parts and divide it in the scanning line direction. Both a straight line perpendicular to the maximum length and a straight line perpendicular to the maximum length in the scanning line direction that divides the area of the light transmission region of the unit cell adjacent to this unit cell on the i-th row into two equal parts. The parallel center line divides the area of the light transmission region of the unit cell closest to the 2nd unit cell in the (i + 1) th row or the (i-1) th row into two equal parts and has the maximum length in the scanning line direction. The i-th row and the (i + 1) -th row or the (i-th) when the unit cells are relatively arranged so as to coincide with a straight line perpendicular to
1) The deviation of the matrix pitch from the row is a, and the maximum length in the scanning line direction and the vertical bisector of the light transmission region of a unit cell on the i-th row and this unit cell on the i-th row The central line parallel to both the vertical bisector of the maximum length in the scanning line direction of the light transmission region of the unit cell adjacent to the unit cell is the 2nd line of the (i + 1) th line or the (i-1) th line. The i-th row when each unit cell is relatively arranged so as to match the maximum length in the scanning line direction of the light transmission region of the unit cell closest to the unit cell, and the (i + 1) th row ) When the deviation of the matrix pitch from the row or the (i-1) th row is b, the deviation of the matrix pitch between the i-th row and the (i + 1) th row or the (i-1) th row The unit cells are arranged relative to each other so that x is a ≦ x ≦ b (a ≦ b) b ≦ x ≦ a (b ≦ a).

The same arrangement is used when the matrix pitch is shifted between adjacent columns.

(Operation) By arranging the picture elements in this manner, as compared with the case where the picture elements are arranged simply row by row in the X direction or column by column in the Y direction, the pixel pitches are substantially completely shifted by a half pitch. Since the optical center of gravity in the unit cell is taken into consideration, the optical center of gravity of each unit cell is balanced and the picture elements are evenly distributed in the entire liquid crystal display element.

(Embodiment) FIG. 1 is a diagram showing an arrangement of unit cells corresponding to picture elements in one embodiment of the present invention.

In FIG. 1, a unit cell corresponding to a picture element including a light transmitting region 10 and a light non-transmitting region 20 is formed by orthogonal scanning lines (X direction,
Row direction), signal line direction (Y direction, column direction) are arranged in a matrix at a predetermined repeating pitch, and in each cell,
The light transmission areas are not symmetrical with respect to at least any straight line parallel to the signal line direction, and the light transmission areas of the picture elements in the same row have the same shape in the same direction. The transmissive region has an inverted shape with the signal line direction as an axis. Here, a is a straight line that divides the area of the light transmission region of a unit cell in the i-th row into two equal parts and that intersects perpendicularly with the maximum length in the X direction, and is also adjacent to this unit cell in the i-th row. A straight line that divides the area of the light transmission region of the unit cell into two equal parts and is perpendicular to the maximum length in the X direction and that is parallel to both is the (i + 1) th row or the (i-1) th row. When the area of the light transmission region of the unit cell closest to the two unit cells is equally divided into two and the unit cells are relatively arranged so as to coincide with a straight line perpendicular to the maximum length in the X direction, I-th
This is the matrix pitch shift between the row and the (i + 1) th row or the (i-1) th row.

b is the maximum length in the X direction of the light transmission region of a unit cell on the i-th row and the perpendicular bisector, and the X direction of the light transmission region of the unit cell also adjacent to this unit cell on the i-th row. And the vertical bisector of the maximum length of
The unit cells are relatively arranged so as to coincide with the vertical bisector of the maximum length in the X direction of the light transmission region of the unit cell that is closest to the second unit cell in the row or (i-1) th row. Is the deviation of the matrix pitch between the i-th row and the (i + 1) -th row or the (i-1) -th row.

In the example of FIG. 1, the unit cells are relatively arranged so that the matrix pitch deviation x between the i-th row and the (i + 1) -th row takes an intermediate value between a and b.

When such a liquid crystal panel is used for color display, for example, as shown in FIG. 1, R (red), G (green), B
A (blue) color filter may be arranged.

In the example of FIG. 1, for the sake of simplicity, only the relative arrangement of the three basic unit cells is shown, but such arrangement is realized at any place on the liquid crystal panel. Needless to say.

Further, here, only the case where the matrix pitch is shifted between the adjacent rows is described, but the same argument holds when the matrix pitch is shifted between the adjacent rows.

By arranging such picture elements, as compared with the case where the picture elements are arranged by shifting the matrix pitch by a half pitch in each row in the X direction or every row in the Y direction, Since the optical center of gravity is taken into consideration, the optical center of gravity of each unit cell is balanced and the picture elements are evenly distributed in the entire liquid crystal display element. Therefore, it is possible to eliminate unnatural patterns unrelated to the displayed contents,
Particularly in the case of color display, R, G, and B are arranged closer to an equilateral triangle, and an unnatural pattern unrelated to the display content can be eliminated even when the number of picture elements is relatively small.

(Effects of the Invention) As described above, the present invention fully considers the area ratio and asymmetry of the light transmission region in the unit cell corresponding to the picture element, and optimizes the relative arrangement of the actual light transmission regions. By adopting this method, it is possible to eliminate an unnatural pattern irrelevant to the display content due to an improper arrangement in the display section of the liquid crystal display element in the light non-transmissive region.

Also, for each picture element arranged in this way, especially R, G,
By arranging the three primary colors of B closer to the equilateral triangle,
It can be evenly distributed and arranged, and a color image having sufficient display quality can be provided even when the number of picture elements is relatively small.

[Brief description of drawings]

FIG. 1 is a diagram showing an arrangement of unit cells corresponding to picture elements in one embodiment of the present invention, FIG. 2 is a plan view of unit cells corresponding to picture elements of a liquid crystal display device, and FIG. 3 is row by row. FIG. 7 is a plan view of a unit cell group in which the matrix pitch is shifted by a half pitch in the X direction. 10 …… Light transmitting area, 20 …… Light non-transmitting area.

Front page continuation (72) Inventor Katsumi Adachi 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (56) Reference JP-A-59-9636 (JP, A)

Claims (4)

[Claims] 1. A unit cell corresponding to a picture element including a light transmissive region and a light non-transmissive region has a scanning line direction which is a row direction orthogonal to each other,
They are arranged in a matrix in a signal line direction which is a column direction at a predetermined repeating pitch, and in each of the cells, the light transmission regions are not symmetrical with respect to at least any straight line parallel to the signal line direction, and are the same. The light-transmitting regions of the picture elements in the rows have the same shape in the same direction, and the light-transmitting regions of the picture elements in the rows adjacent to each other have a shape inverted around the signal line direction. The area of the light transmission region of the unit cell is divided into two equal parts, and the area of the light transmission region of the unit cell adjacent to this unit cell in the i-th row is also divided into two parts. A unit cell in which a median line that is divided and is parallel to both the maximum length in the scanning line direction and a straight line that intersects vertically is closest to the two unit cells in the (i + 1) th row or the (i-1) th row. The area of the light transmission area of the The i-th row when the unit cells are arranged relative to each other so as to coincide with the straight line
1) The deviation of the matrix pitch from the 1st row or the (i-1) th row is a, and the vertical bisector of the maximum length in the scanning line direction of the light transmission region of the unit cell on the i-th row, Similarly, the middle line parallel to both the vertical bisector of the maximum length in the scanning line direction of the light transmission region of the unit cell adjacent to this unit cell on the i-th row is the (i + 1) -th row or the ( i-1) When each unit cell is relatively arranged so as to match the maximum length in the scanning line direction of the light transmission region of the unit cell closest to the second unit cell in the row and the vertical bisector When the deviation of the matrix pitch between the i-th row and the (i + 1) -th row or the (i-1) -th row is b, the i-th row and the (i + 1) -th row or the (i-th) row
-1) The unit cells are arranged relative to each other such that the matrix pitch deviation x from the row is a ≦ x ≦ b (a ≦ b) b ≦ x ≦ a (b ≦ a) Liquid crystal display device. 2. R (red), G corresponding to each unit cell
The liquid crystal display element according to claim 1, wherein (green) and B (blue) color filters are arranged in a predetermined repeating manner. 3. A unit cell corresponding to a picture element including a light transmissive region and a light non-transmissive region has a scanning line direction which is a row direction orthogonal to each other,
They are arranged in a matrix in a signal line direction which is a column direction at a predetermined repeating pitch, and in each of the cells, the light transmission regions are not symmetrical with respect to at least any straight line parallel to the signal line direction, and are the same. The light transmission areas of the picture elements in the columns have the same shape in the same direction, and the light transmission areas of the picture elements in the columns adjacent to each other have a shape inverted with respect to the scanning line direction. The area of the light transmission region of the unit cell is divided into two equal parts, and the area of the light transmission region of the unit cell adjacent to this unit cell in the j-th column is also divided into two parts. A unit cell in which a middle line that is divided and is parallel to both the maximum length in the signal line direction and a straight line that perpendicularly intersects is closest to the two unit cells in the (j + 1) th column or the (j-1) th column. The area of the light transmission area of the Crossing a straight line, the j-th column when the unit cells are arranged relative to each other and the (j +
1) Let c be the shift of the matrix pitch from the column or the (j-1) th column, and set the vertical bisector of the maximum length in the signal line direction of the light transmission region of the unit cell at the jth column, Similarly, the center line parallel to both the vertical bisector of the maximum length in the signal line direction of the light transmission region of the unit cell adjacent to this unit cell in the j-th column is the (j + 1) -th column or the ( j-1) When the unit cells are relatively arranged so as to coincide with the vertical bisector of the maximum length in the signal line direction of the light transmission region of the unit cell closest to the second unit cell in the column When the matrix pitch difference between the j-th column and the (j + 1) -th column or the (j-1) -th column is d, the j-th column and the (j + 1) -th column or the (j-th column)
-1) The unit cells are arranged relative to each other such that the matrix pitch deviation y from the column is: c≤y≤d (c≤d) d≤y≤c (d≤c) Liquid crystal display device. 4. R (red), G corresponding to each unit cell
4. The liquid crystal display element according to claim 3, wherein (green) and B (blue) color filters are arranged in a predetermined repeating manner.