JP5246758B2 - LCD panel - Google Patents

Description

  The present invention relates to an FFS (Fringe Field Switching) mode liquid crystal display panel, and more particularly to an FFS mode liquid crystal display panel having a slit in which two slit portions having different stretching directions are combined.

  Liquid crystal display panels are characterized by their light weight, thinness, and low power consumption compared to CRTs (cathode ray tubes), and are therefore used in many electronic devices for display purposes. The liquid crystal display panel is aligned with liquid crystal molecules in a predetermined direction by rubbing the alignment film, and the direction of these liquid crystal molecules is changed by an electric field to change the amount of light transmitted or reflected. An image is displayed.

  As a method of applying an electric field to a liquid crystal layer of a liquid crystal display panel, there are a vertical electric field type and a horizontal electric field type. A vertical electric field type liquid crystal display panel applies a substantially vertical electric field to liquid crystal molecules by a pair of electrodes arranged with a liquid crystal layer interposed therebetween. Known examples of the vertical electric field type liquid crystal display panel include a TN (Twisted Nematic) mode, a VA (Vertical Alignment) mode, and an MVA (Multi-domain Vertical Alignment) mode. A horizontal electric field type liquid crystal display panel is provided with a pair of electrodes insulated from each other on one inner surface side of a pair of substrates disposed with a liquid crystal layer interposed therebetween, and a substantially horizontal electric field is applied to liquid crystal molecules. To be applied. As this lateral electric field type liquid crystal display panel, there are known an IPS (In-Plane Switching) mode in which a pair of electrodes do not overlap in a plan view and an FFS mode panel in which a pair of electrodes overlap in a plan view.

  Among these, in the FFS mode liquid crystal display panel, a pair of electrodes consisting of an upper electrode and a lower electrode are arranged in different layers with an insulating film interposed therebetween, and a slit-like opening is provided in the upper electrode, and generally passes through this slit. A horizontal electric field is applied to the liquid crystal layer. The FFS mode liquid crystal display panel is widely used in recent years because it can obtain a wide viewing angle and improve image contrast.

  By the way, in a liquid crystal display panel for color display, usually three sub-pixels of R (red), G (green), and B (blue) are formed side by side, and one pixel is formed by combining these three sub-pixels. (1 pixel) is set. Since one pixel is generally square, one subpixel is a vertically long rectangle. Therefore, in the FFS mode liquid crystal display panel, since an electric field in a desired direction cannot be formed at both ends of the slit formed in the upper electrode, as shown in Patent Documents 1 and 2, The stretching direction is set to the longitudinal direction to reduce the decrease in the aperture ratio.

In the FFS mode liquid crystal display panel, the slit is extended so as to be slightly inclined with respect to the rubbing direction so that the liquid crystal molecules can rotate in the same direction. In a liquid crystal display panel for color display, a change in color due to a viewing angle can be reduced by multi-domaining in which the inclination angle of the slit is divided into two areas, positive and negative. However, since both ends of the slit cannot form an electric field in a desired direction, when slits with different stretching directions are separated, the number of ends of the slit increases and the aperture ratio decreases. Therefore, in the liquid crystal display panel disclosed in Patent Document 3 below, a multi-domain structure with a wide aperture ratio is achieved by connecting slits extending in different directions.
JP 2002-014374 A JP 2003-322869 A JP 2007-264231 A

  As described above, when two slits having different stretching directions are formed, domains having different alignment directions of liquid crystal molecules are formed on the respective slit sides, so that there is an advantage that a high aperture ratio and a wide viewing angle characteristic can be obtained. is there. However, if two slits with different stretching directions are connected to form a “<” shape, domains with different orientation directions come and go to each other, resulting in orientation disturbance (ripple), especially on the surface of the liquid crystal display panel. There is a problem that the ripple generated when the button is pressed does not disappear.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide two slit portions with different stretching directions in which ripple ripples generated when the surface of the liquid crystal display panel is pushed are easily lost. It is an object of the present invention to provide an FFS mode liquid crystal display panel having slits coupled to each other.

In order to achieve the above object, a liquid crystal display panel according to the present invention has a pair of substrates disposed to face each other with a liquid crystal layer interposed therebetween, and an upper electrode in which a plurality of slits are formed on one of the pair of substrates. A lower electrode formed on the substrate side through the upper electrode and an insulating film, and an alignment film formed to cover the surface of the upper electrode and the insulating film , the upper electrode and the An FFS mode liquid crystal display panel in which an electric field generated between the lower electrode and the liquid crystal layer is applied to the liquid crystal molecules , wherein each of the plurality of slits is formed in parallel with a liquid crystal alignment direction in a voltage-free state. and a linear moiety, that equipped with a extension portion extending in a direction away symmetrically from both ends of the straight portion and a direction perpendicular to the linear portion as an axis.

  The liquid crystal display panel of the present invention covers an upper electrode formed with a plurality of slits, a lower electrode formed on the substrate side through the upper electrode and an insulating film, and a surface of the upper electrode and the insulating film An alignment film formed as described above. With this configuration, the liquid crystal display panel of the present invention operates in the FFS mode. As the insulating film, an inorganic insulating film such as silicon oxide or silicon nitride can be used. Further, transparent conductive materials such as ITO (Indium Tin Oxide) or IZO (Indium Zinc Oxide) are used as the upper electrode and the lower electrode. In the liquid crystal display panel of the present invention, both the upper electrode and the lower electrode can operate as a pixel electrode or a common electrode.

  In the liquid crystal display panel of the present invention, each of the plurality of slits of the upper electrode has a straight line portion formed in parallel with the liquid crystal alignment direction in the voltage-free state and a direction orthogonal to the straight line portion as an axis. Extending portions extending in directions symmetrically spaced from each other from both ends of the linear portion. The shape of such a slit is as if the slit had a straight portion formed in a "<"-shaped bent portion, and the straight portion was placed in parallel with the liquid crystal alignment direction when no voltage was applied. . In the present invention, the liquid crystal alignment direction when no voltage is applied coincides with the rubbing direction when the alignment film is rubbed.

  Domains in which the alignment direction of liquid crystal molecules are different between the linear portion and the extended portion of the slit, respectively, but since the direction of the electric field changes in plan view between the linear portion and the extended portion of the slit, It becomes difficult to come and go. In addition, if the straight line portion of the slit is formed in parallel with the liquid crystal alignment direction when no voltage is applied, the angle between the liquid crystal alignment and the electric field direction when no voltage is applied is close to 90 °. The rotational force produced is small. On the other hand, in the stretched portion of the slit, the angle between the liquid crystal alignment and the direction of the electric field when no voltage is applied is small, so that the rotational force applied to the liquid crystal molecules is larger than in the straight portion of the slit. Therefore, according to the liquid crystal display panel of the present invention, even if the rotation angle of the liquid crystal molecules changes and a ripple occurs when pressed from the surface of the liquid crystal display panel, the rotational force applied to the liquid crystal molecules in the stretched portion of the slit. Since it is strong, it becomes easy to return to the original state.

  In addition, in the liquid crystal display panel of the present invention, the extending portion of the slit is extended in a direction that is symmetrically spaced from both ends of the linear portion with a direction orthogonal to the linear portion as an axis. As described above, when two slit portions having different stretching directions are formed, domains having different alignment directions of liquid crystal molecules are formed in the respective slit portions, so that wide viewing angle characteristics can be obtained.

  Further, in the liquid crystal display panel, the light transmittance changes as a result of the change in the birefringence of the liquid crystal accompanying the change in the driving voltage. This characteristic is referred to as a voltage transmission (VT) characteristic. The variation in the light transmittance of the liquid crystal display panel due to such a change in driving voltage causes a phenomenon of coloring because the amount of variation varies depending on the wavelength of light. In the case of an FFS mode liquid crystal display panel, the VT characteristic varies depending on the angle formed by the longitudinal direction of the slit of the upper electrode and the liquid crystal alignment direction when no voltage is applied.

  In the liquid crystal display panel of the present invention, the angle between the linear portion and the extended portion of the slit of the upper electrode differs from the liquid crystal alignment direction in the voltage-free state. With such a configuration, the angle formed by the liquid crystal alignment direction when no voltage is applied is different between the straight portion and the stretched portion of the slit, and therefore the VT characteristics that are different between the straight portion and the stretched portion of the slit. It will be equipped with. Thus, when the slit of the upper electrode has a plurality of VT characteristics, the plurality of VT characteristics are superimposed and have a VT characteristic represented by the envelope. Therefore, according to the liquid crystal display panel of the present invention, it is possible to obtain a liquid crystal display panel that has good viewing angle characteristics and is less likely to be colored.

  In the liquid crystal display panel of the present invention, it is preferable that each of the slits has a length of the linear portion of 5 μm to 10 μm, and the length of the extended portion is longer than the length of the linear portion.

  In the liquid crystal display panel according to such an embodiment, domains having different alignment directions of liquid crystal molecules are generated in the linear portion and the extended portion of the slit. The straight part of the slit has the effect that the ripple generated when pressed from the surface of the liquid crystal display panel tends to disappear, but it does not directly improve the viewing angle characteristics. The length is preferably shorter than the length of the stretched portion. If the length of the straight line portion of the slit formed on the upper electrode is less than 5 μm, it becomes substantially the same as the state where the straight line portion of the slit does not exist, and domains having different liquid crystal orientation directions easily come and go. This is not preferable. If the length of the straight portion of the slit exceeds 10 μm, the size of the sub-pixel is small, so that the length of the extending portion of the slit cannot be made longer than that of the straight portion, so that the effect of improving the viewing angle characteristics is lost. .

  In the liquid crystal display panel of the present invention, it is preferable that the angle of the acute angle portion formed by the straight portion of the slit and the extended portion is 15 ° to 25 °.

  If the angle of the acute angle portion formed by the straight portion and the stretched portion of the slit is less than 15 °, the effect of improving the viewing angle characteristics is lost, as in the case where substantially all the slits are linear. When the angle of the acute angle portion formed by the straight portion and the stretched portion of the slit exceeds 25 °, the viewing angle characteristics are improved, but the boundary between domains having different liquid crystal alignment directions becomes conspicuous. It leads to. According to the liquid crystal display panel of this aspect, since the angle of the acute angle portion formed by the straight portion and the extended portion of the slit is set to 15 ° to 25 °, the liquid crystal display with good display image quality while achieving good viewing angle characteristics. A display panel is obtained.

  In the liquid crystal display panel of the present invention, it is preferable that the liquid crystal alignment direction when no voltage is applied is an extending direction of signal lines formed in the liquid crystal display panel.

  In a liquid crystal display panel for color display, one subpixel is usually a vertically long rectangle. In the FFS mode liquid crystal display panel, an electric field in a desired direction cannot be formed at both ends of the slit formed in the upper electrode. Therefore, if the number of both ends of the slit is large, the aperture ratio decreases. In the liquid crystal display panel of this aspect, the liquid crystal alignment direction when no voltage is applied is the extending direction of the signal lines formed in the liquid crystal display panel, and the linear portion of the slit is the liquid crystal alignment when no voltage is applied. It is designed to be parallel to the direction. Therefore, according to the liquid crystal display panel of this aspect, the slit can be formed and arranged in the upper electrode efficiently while reducing the area of the closed end of the slit-shaped opening that cannot perform normal display. A liquid crystal display panel capable of large and bright display can be obtained.

  In the liquid crystal display panel of the present invention, it is preferable that the lower electrode is formed on the surface of an interlayer film formed on the substrate.

  When the lower electrode is formed on the surface of the interlayer film formed on the substrate, the lower electrode, the insulating film, and the upper electrode constituting the FFS mode liquid crystal display panel are all disposed on the interlayer film. Therefore, according to the liquid crystal display panel of the aspect, the upper electrode and the lower electrode can be arranged over a wide area range of each pixel region, and the FFS mode capable of bright display with a larger aperture ratio. A liquid crystal display panel is obtained. As the interlayer film, a photosensitive or non-photosensitive resin material having good transparency and excellent electrical insulation can be appropriately selected and used.

  Hereinafter, the best embodiment of the present invention will be described with reference to the drawings. However, the embodiment described below shows an example for embodying the technical idea of the present invention, and is not intended to specify the present invention as the first embodiment. Other embodiments included in are equally applicable. In each drawing used for the description in this specification, each layer and each member are displayed in different scales so that each layer and each member can be recognized on the drawing. However, it is not necessarily displayed in proportion to the actual dimensions.

  FIG. 1 is a plan view of one sub-pixel of the FFS mode liquid crystal display panel of the first embodiment. 2A is a cross-sectional view taken along line IIA-IIA in FIG. 1, and FIG. 2B is a cross-sectional view taken along line IIB-IIB in FIG. FIG. 3 is a schematic diagram showing the shape relationship of each part of one slit shown in FIG. FIG. 4 is a graph showing the relationship between the angle between the slit and the liquid crystal alignment direction when no voltage is applied and the VT characteristics. FIG. 5 is a plan view of one sub pixel of the liquid crystal display panel of the second embodiment.

[First Embodiment]
A liquid crystal display panel 10A according to the first embodiment will be described with reference to FIGS. The liquid crystal display panel 10A includes an array substrate AR and a color filter substrate CF. The array substrate AR crosses the surface of the display area of the first transparent substrate 11 such as a glass substrate in a state where a plurality of scanning lines 12 and signal lines 13 are insulated from each other by the gate insulating film 14. Further, common wiring (not shown) is formed at the peripheral edge of the display area. Each region surrounded by the scanning lines 12 and the signal lines 13 forms one subpixel. Further, for example, a TFT is formed as a switching element for each pixel on the first transparent substrate 11, and the entire surface of the first transparent substrate 11 including the TFT is made of, for example, a silicon nitride layer or a silicon oxide layer. Covered with a passivation film 15.

  An interlayer film 16 made of an organic material is formed on the surface of the passivation film 15, and a contact hole 17 is formed in the interlayer film 16 and the passivation film 15 at a position corresponding to the drain electrode D of the TFT. . A lower electrode 18 made of a transparent conductive material such as ITO or IZO is formed on the surface of the interlayer film 16 so as to cover the surface except for the region where the TFT is formed and the region where the contact hole 17 is formed. Is formed. The lower electrode 18 is connected to a common wiring at a peripheral portion of a display area (not shown) and operates as a common electrode.

  An insulating film 19 made of a silicon nitride layer or a silicon oxide layer is formed over the entire surface of the first transparent substrate 11 on which the lower electrode 18 is formed. On the surface of the insulating film 19, an upper electrode 22 made of a transparent conductive material such as ITO or IZO is formed in each subpixel. The upper electrode 22 has a slit 20A having a predetermined shape. Details of the slit 20A will be described later.

  The upper electrode 22 is electrically connected to the drain electrode D of the TFT via the contact hole 17 and operates as a pixel electrode. Note that it is arbitrary which of the upper electrode 22 and the lower electrode 18 is connected to the drain electrode D of the TFT and which is electrically connected to the common wiring. Further, the first alignment film 24 is formed over the entire display region, including the surface of the upper electrode 22 and the inside of the slit 20A. The first alignment film 24 is rubbed in a predetermined direction R in order to align liquid crystal molecules in a predetermined direction. This rubbing treatment shows an example for specifying the liquid crystal alignment direction in the voltage non-application state in the present invention.

  Further, as shown in FIGS. 2A and 2B, the color filter substrate CF is formed on the surface of the second transparent substrate 25 such as a glass substrate on the scanning line 12, the signal line 13, the contact hole 17 and the TFT of the array substrate AR. A light-shielding film 26 is formed so as to cover the position corresponding to. Further, a color filter layer 27 of a predetermined color is formed on the surface of the second transparent substrate 25 surrounded by the light shielding film 26. An overcoat layer 28 is formed so as to cover the surfaces of the light shielding film 26 and the color filter layer 27. A second alignment film 29 is formed on the surface of the overcoat layer 28. The second alignment film 29 is rubbed in a direction shifted by 180 ° from the first alignment film.

  The array substrate AR and the color filter substrate CF are arranged to face each other so that the upper electrode 22 of the array substrate AR and the color filter layer 27 of the color filter substrate CF are opposed to each other, and the liquid crystal 30 is sealed therebetween. . Further, a first polarizing plate 31 and a backlight device (not shown) are arranged outside the array substrate AR, and a second polarizing plate 32 is arranged outside the color filter substrate CF, and the liquid crystal display according to the first embodiment. Panel 10A is completed.

  Here, the shape of each part of one slit 20A of the liquid crystal display panel 10A of the first embodiment will be described with reference to FIGS. Each of the slits 20A extends in a direction that is symmetrically spaced from both ends of the straight line portion 20a1, with a straight line portion 20a1 extending parallel to the rubbing direction R of the alignment film 24 and a direction orthogonal to the straight line portion 20a1 as an axis. Extending portions 20a2 and 20a3 are formed. That is, the slit 20 </ b> A is in a state in which a straight portion is formed in a “<”-shaped bent portion, and the straight portion is arranged in parallel with the rubbing direction R of the first alignment film 24. .

  In the FFS mode liquid crystal display panel, the direction of the electric field generated between the upper electrode and the lower electrode is the normal direction of the side of the slit. For this reason, in the liquid crystal display panel 10A of the first embodiment, the linear portion 20a1 of the slit 20A and the extended portions 20a2 and 20a3 have domains in which the alignment directions of the liquid crystal molecules are different, but the direction of the electric field changes in plan view. Therefore, it is difficult for domains having different orientation directions to go back and forth.

  The straight portion 20a1 of the slit 20A is formed in parallel with the rubbing direction R. Therefore, in the straight portion 20a1 of the slit 20A, the angle formed by the rubbing direction R and the direction of the electric field is close to 90 °, so that the rotational force applied to the liquid crystal molecules is small. On the other hand, in the extended portions 20a2 and 20a3 of the slit 20A, the angle formed between the rubbing direction R and the electric field direction is smaller than 90 °, so that the rotational force applied to the liquid crystal molecules is larger than that of the straight portion 20a1 of the slit 20A. Become. Therefore, according to the liquid crystal display panel 10A of the first embodiment, even when the rotation angle of the liquid crystal molecules changes and a ripple occurs when pressed from the surface of the liquid crystal display panel 10A, the extended portions 20a2 and 20a3 of the slit 20A. Then, since the rotational force given to the liquid crystal molecules is strong, it is easy to return to the original state.

  Moreover, in the liquid crystal display panel 10A of the first embodiment, the extending portions 20a2 and 20a3 of the slit 20A of the upper electrode 22 are symmetrically separated from both ends of the linear portion 20a1 with the direction orthogonal to the linear portion 20a1 as an axis. Is stretched. As described above, when two slit portions having different stretching directions are formed, domains having different alignment directions of liquid crystal molecules are formed in the respective slit portions, so that wide viewing angle characteristics can be obtained.

  In the liquid crystal display panel 10A of the first embodiment, the angle θ of the acute angle portion formed by the straight portion 20a1 of the slit 20A and the extended portions 20a2 and 20a3 is selected so as to satisfy the relationship of 15 ° ≦ θ ≦ 25 °. ing. Moreover, the length L of the straight portion 20a1 of the slit 20A is selected so as to satisfy the relationship of 5 μm ≦ L ≦ 15 μm, and the lengths of the extended portions 20a2 and 20a3 are selected to be longer than the length of the straight portion 20a1. ing.

  When the angle θ of the acute angle portion formed by the straight portion 20a1 of the slit 20A and the extended portions 20a2 and 20a3 is less than 15 °, substantially the same as when all the slits are straight, and the viewing angle characteristics are improved. The effect is lost. In addition, when the angle θ of the acute angle portion formed by the straight portion 20a1 of the slit 20A and the extended portions 20a2 and 20a3 exceeds 25 °, the viewing angle characteristics are improved, but the boundary between domains having different liquid crystal alignment directions is conspicuous. As a result, the display image quality is degraded. Therefore, in the liquid crystal display panel 10A of the first embodiment, a favorable viewing angle characteristic is achieved by setting the angle of the acute angle portion formed by the straight portion 20a1 of the slit 20A and the extended portions 20a2 and 20a3 to 15 ° to 25 °. In addition, a liquid crystal display panel 10A with good display image quality can be obtained.

  Furthermore, in the liquid crystal display panel 10A of the first embodiment, the linear portion 20a1 of the slit 20A has an effect that the ripple generated when pressed from the surface of the liquid crystal display panel 10A is easily lost. Since it is not directly useful for improving the corner characteristics, it is preferable that the length is shorter than the lengths of the stretched portions 20a2 and 20a3. When the length of the straight line portion 20a1 is less than 5 μm, it becomes substantially the same as the state where the straight line portion 20a1 of the slit 20A does not exist, and domains having different alignment directions of the liquid crystal easily come and go. Further, if the length of the straight portion 20a1 of the slit 20A exceeds 10 μm, the length of the extended portions 20a2 and 20a3 cannot be made longer than that of the straight portion 20a1 due to the small size of the sub-pixel, so that the viewing angle characteristics are improved. The effect will be lost.

  In general, the liquid crystal display panel changes the light transmittance as a result of the change in the birefringence of the liquid crystal as the drive voltage changes, as is known as the voltage transmittance (VT) characteristic. Such a change in light transmittance due to a change in drive voltage causes a phenomenon of coloring because the amount of change varies depending on the wavelength of light. In the case of the FFS mode liquid crystal display panel, the VT characteristic varies depending on the angle formed by the longitudinal direction of the slit of the upper electrode and the rubbing direction. This relationship is shown in FIG. That is, the curves θ1 and θ2 in FIG. 4 show cases where the angles formed by the longitudinal direction of the slit and the rubbing direction are θ1 and θ2, respectively.

  In the liquid crystal display panel 10A of the first embodiment, the linear portion 20a1 and the extended portions 20a2 and 20a3 of the upper electrode slit 20A have different angles with respect to the rubbing direction R. Therefore, in the liquid crystal display panel 10A of the first embodiment, the linear portion 20a1 of the slit 20A and the extended portions 20a2 and 20a3 have different VT characteristics. As described above, when the slit 20A of the upper electrode 22 has a plurality of VT characteristics, the plurality of VT characteristics are superimposed and have a VT characteristic represented by the envelope. Therefore, according to the liquid crystal display panel 10A of the first embodiment, it is possible to obtain a liquid crystal display panel that has good viewing angle characteristics and is less likely to be colored.

  As described above, when two slits having different stretching directions are connected in a “<” shape, domains having different alignment directions of liquid crystal molecules respectively formed by the two slits having different stretching directions can come and go. Therefore, in an FFS mode liquid crystal display panel in which two slits having different stretching directions are connected in a “<” shape, a ripple defect may occur in which an abnormal alignment region remains on one side as it is when a push test or the like is performed. . Also in the liquid crystal display panel 10A of the first embodiment, domains having different alignment directions of liquid crystal molecules are generated in the straight portion 20a1 and the stretched portions 20a2 and 20a3 of the slit 20A. However, in the liquid crystal display panel 10A of the first embodiment, the linear portion 20a1 of the slit 20A and the extended portions 20a2 and 20a3 have a change in the direction of the electric field in plan view, and therefore domains having different orientation directions are unlikely to go back and forth. Become.

  Moreover, in the liquid crystal display panel 10A of the first embodiment, the rubbing direction R is a direction along the signal line 13 formed in the liquid crystal display panel 10A. In a liquid crystal display panel for color display, one subpixel is usually a vertically long rectangle. In the FFS mode liquid crystal display panel, an electric field in a desired direction cannot be formed at both ends of the slit formed in the upper electrode. Therefore, if the number of both ends of the slit is large, the aperture ratio decreases. Therefore, in the liquid crystal display panel 10A of the first embodiment, the rubbing direction R is the direction along the signal line 13 formed in the liquid crystal display panel 10A, and the straight portion 20a1 of the slit 20A is the rubbing direction R. So that it is parallel to According to the liquid crystal display panel 10A of the first embodiment as described above, the slit 20A can be formed in the upper electrode 22 efficiently while reducing the area of the closed end of the slit 20A that cannot perform normal display. A liquid crystal display panel having a large aperture ratio and capable of displaying brightly is obtained.

  As the liquid crystal display panel 10A of the first embodiment, an example in which the lower electrode 18 is formed on the surface of the interlayer film 16 is shown. When the lower electrode 18 is thus formed on the surface of the interlayer film 16, the lower electrode 18, the insulating film 19 and the upper electrode 22 constituting the FFS mode liquid crystal display panel 10A are all disposed on the interlayer film 16. It will be. Therefore, according to the liquid crystal display panel 10A of the first embodiment, the upper electrode 22 and the lower electrode 16 can be arranged over a wide area range of each pixel region, so that the aperture ratio is larger and brighter. An FFS mode liquid crystal display panel 10A capable of display is obtained. As a material for forming the interlayer film 16, a photosensitive or non-photosensitive resin material having good transparency and excellent electrical insulation can be appropriately selected and used.

[Second Embodiment]
In the liquid crystal display panel 10A of the first embodiment, the rubbing direction R is the direction along the signal line 13 formed in the liquid crystal display panel 10A. However, the liquid crystal display panel of the present invention has the same effect even when the rubbing direction R extends along the scanning line 12. A liquid crystal display panel 10B according to the second embodiment in which the linear slit 20b1 of the slit 20B extends along the scanning line 12 is shown in FIG. In the liquid crystal display panel 10B of the second embodiment, the slit 20B has a straight portion 20b1 extending parallel to the rubbing direction R, and an extended portion 20b2 extending in directions that are symmetrically spaced from both ends of the straight portion 20b1, respectively. 20b3. The liquid crystal display panel 10B according to the second embodiment is the same as the liquid crystal display panel 10A according to the first embodiment except for the configuration of the slit 20B. Therefore, in FIG. 5, the same reference numerals are given to the same components as those of the liquid crystal display panel 10A of the first embodiment, and the detailed description thereof is omitted. Also in the liquid crystal display panel 10B of the second embodiment, substantially the same effect as the liquid crystal display panel 10A of the first embodiment can be obtained.

FIG. 2 is a plan view of one sub pixel of the FFS mode liquid crystal display panel of the first embodiment. 2A is a cross-sectional view taken along line IIA-IIA in FIG. 1, and FIG. 2B is a cross-sectional view taken along line IIB-IIB in FIG. It is a schematic diagram which shows the shape relationship of each part of one slit shown in FIG. It is a graph showing the relationship between the angle | corner and the VT characteristic which a slit and the liquid crystal orientation direction in a voltage no application state make. It is a top view for 1 sub pixel of the liquid crystal display panel of 2nd Embodiment.

Explanation of symbols

  10A, 10B: liquid crystal display panel 11: first transparent substrate 12: scanning line 13: signal line 14: gate insulating film 15: passivation film 16: interlayer film 17: contact hole 18: lower electrode 18: insulating film 20A, 20B : Slits 20a1, 20b1: linear portions of slits 20a2, 20a3, 20b2, 20b3: extended portions of slits 22: upper electrode 24: first alignment film 25: second transparent substrate 26: light shielding film 27: color filter layer 28 : Overcoat layer 29: Second alignment film 30: Liquid crystal 31: First polarizing plate 32: Second polarizing plate AR: Array substrate CF: Color filter substrate

Claims (5)

A pair of substrates disposed opposite to each other with a liquid crystal layer sandwiched therebetween; an upper electrode having a plurality of slits formed on one of the pair of substrates; and the upper electrode and an insulating film on the substrate side A liquid crystal molecule of the liquid crystal layer, wherein the electric field generated between the upper electrode and the lower electrode is provided with a lower electrode formed and an alignment film formed to cover the surface of the upper electrode and the insulating film. In the FFS mode liquid crystal display panel applied to the
Each pre Kiss lit, and a linear portion formed in parallel to the liquid crystal alignment direction in the absence of an applied voltage,
It said linear portion and the linear portion extension portion and the liquid crystal display panel that provides a respectively extending in the direction away symmetrically from both ends of an axis and a direction orthogonal. Each of the slits, the the length of the linear portion is 5 m to 10 m, the liquid crystal display panel according the length of the extension portion in the length I請 Motomeko 1 than the length of the linear portion. Said linear portion and said extension portion and the liquid crystal display panel of the angle of acute angle portions according to 請 Motomeko 1 Ru 15 ° to 25 ° der of the slit. The liquid crystal alignment direction in the voltage non-application state, the liquid crystal display panel according to 請 Motomeko 1 extends Ru extending direction der of signal lines the formed on the liquid crystal display panel. The lower electrode, the liquid crystal display panel according to any one of 請 Motomeko 1-4 that are formed on the surface of the interlayer film formed on the substrate.

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