JP2008242374A - Electrooptical device and electronic equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a transverse electric field type electrooptical device having a two-terminal type nonlinear element, capable of providing high display quality. <P>SOLUTION: The liquid crystal display device has an array substrate and a color filter (CF) substrate between which a liquid crystal is held. Corresponding to sub-pixel regions arrayed in a plurality of rows and a plurality of columns, the array substrate has TFD elements, pixel electrodes connected thereto, and a common electrode prod generating an electric field with pixel electrodes. Consequently, an FFS type liquid crystal device is constituted which has the TFD elements. Especially, the respective common electrodes are formed of ITO, and the common electrodes arrayed in respective row directions are connected directly to respective common wiring lines made of metal films provided on the array substrate. Consequently, connection structures of the respective common electrodes arrayed in the respective row directions and common wiring lines can be reduced in resistance value. Consequently, striped display unevenness etc., can be prevented from being generated by rows to obtain high display quality. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an electro-optical device suitable for use in displaying various information.

  Currently, a horizontal electric field type liquid crystal device (electro-optical device) represented by an IPS (In-Plane Switching) method, an FFS (Fringe Field Switching) method, or the like is suitably used as various display devices such as portable devices. . This method is a method in which the direction of the electric field applied to the liquid crystal is substantially parallel to the substrate, and has an advantage that a high transmittance and a high viewing angle characteristic can be obtained as compared with a TN (Twisted Nematic) method or the like. .

  Note that Patent Document 1 describes a horizontal electric field type liquid crystal device using a TFD (Thin Film Diode) element.

JP 2007-025521 A

  It is an object of the present invention to provide a transverse electric field type electro-optical device including a two-terminal nonlinear element capable of obtaining high display quality and an electronic apparatus using the same.

  In one aspect of the present invention, an electro-optical device includes an electro-optical layer sandwiched between an array substrate and a counter substrate, and an overlapping region between the array substrate and the counter substrate includes a plurality of rows and a plurality of columns. A plurality of two-terminal nonlinear elements, and a plurality of first electrodes electrically connected to each of the two-terminal nonlinear elements; A plurality of second electrodes for generating an electric field with each of the first electrodes, and each of the two-terminal nonlinear element, the first electrode, and the second electrode, In the array substrate, provided corresponding to each of the sub-pixel regions, each of the second electrodes is formed of a transparent conductive film, and each of the second electrodes arranged in each row direction is Metal film provided on the array substrate Li Cheng are directly connected to each common wiring.

  The electro-optical device includes an electro-optical layer sandwiched between an array substrate and a counter substrate. In a region where the array substrate and the counter substrate overlap, a sub-pixel region serving as a minimum unit of display arranged in a plurality of rows and a plurality of columns is provided. The array substrate includes a plurality of two-terminal nonlinear elements (eg, TFD elements), a plurality of first electrodes (eg, pixel electrodes) electrically connected to each of the two-terminal nonlinear elements, A plurality of second electrodes (for example, common electrodes) that generate an electric field with each of the first electrodes. Each of the two-terminal nonlinear element, the first electrode, and the second electrode is provided corresponding to each sub-pixel region in the array substrate. In a preferred example, the electric field may be a fringe field having a strong electric field component in a direction substantially parallel to the substrate surface of the array substrate when the electro-optic layer is driven. As a result, an FFS type electro-optical device as an example of a lateral electric field type including a two-terminal nonlinear element can be configured.

  In particular, in this electro-optical device, each of the second electrodes is formed of a transparent conductive film, and each of the second electrodes arranged in each row direction is a metal film provided on the array substrate. Directly connected to each common wiring. In a preferred example, the second electrode is preferably formed of ITO, and each of the common wirings is a metal film of any one of Cr, Ag, and Al, or a metal film including any of these. It is preferable that it is formed by.

  Thereby, each of the second electrodes arranged in each row direction is compared with the comparative example in which the connection structure of each of the second electrodes arranged in each row direction and each common wiring is formed of only ITO. The resistance value of the connection structure between each and each common wiring can be lowered. As a result, it is possible to reduce the thickness of the second electrode made of the transparent conductive film. When the second electrode has a comb-teeth shape, the liquid crystal molecules are abnormally aligned near the outer shape of the comb-teeth portion. Is less likely to occur, and light leakage near the outer shape can be prevented, and the contrast can be improved. In addition, by this, the first electrode located on the side closer to the input side of the electric signal (for example, the scanning signal) and the first electrode located on the side farther from the input side of the electric signal. , V (voltage) -T (transmittance) characteristics can be prevented from being different, and stripe-like display unevenness can be prevented from being generated for each row, so that high display quality can be obtained.

  In one aspect of the electro-optical device, each of the common wirings is formed of a light-shielding metal film, and is adjacent to the arbitrary sub-pixel region and the sub-pixel region in the column direction. It is arranged in the vicinity of the boundary with the other sub-pixel region. Thereby, it is possible to improve the aperture ratio while causing each common wiring to function as a light shielding layer.

  In another aspect of the electro-optical device, each common wiring has a linear shape extending in the row direction, and the two-terminal type provided corresponding to the arbitrary sub-pixel region It is disposed at a position that overlaps with and directly connects to the end of the second electrode that exists at a position that partially and planarly overlaps the nonlinear element.

  According to this aspect, each of the second electrodes arranged in each row direction is directly connected to one linear common wiring at the position of the end of each of the second electrodes. Therefore, the resistance value of the connection structure between each of the second electrodes arranged in each row direction and each common wiring can be reduced. In addition, in this way, each common wiring is disposed at a position overlapping with the end portion of the second electrode existing at a position overlapping partially and planarly with the two-terminal nonlinear element that does not contribute to display in the sub-pixel region. Thus, it is possible to improve the aperture ratio while causing each common wiring to function as a light shielding layer.

  In another aspect of the electro-optical device, each of the common wirings includes a linear first wiring and a linear second wiring extending in the same direction as the extending direction of the first wiring. And the first wiring is present at a position that partially and planarly overlaps the two-terminal nonlinear element provided corresponding to the arbitrary sub-pixel region. The second wiring is located on the opposite side to the end of the second electrode, and overlaps with the end of the second electrode. It is directly connected to a position overlapping with the other end portion of the second electrode existing at a position partially and planarly overlapped with the other two-terminal nonlinear element provided corresponding to the sub-pixel region. It is arranged at the position.

  According to this aspect, each of the second electrodes arranged in each row direction has a pair of first wiring and second wiring at the position of each end or other end of the second electrode. Connected directly. Therefore, each of the second electrodes arranged in each row direction and each common wiring are compared with the connection structure in which each of the second electrodes arranged in each row direction is directly connected to one metal wiring. The resistance value of the connection structure with the first and second wirings can be further reduced. Further, in the case of this aspect, even if one of the pair of first and second wirings is disconnected, the wiring on the side that is not disconnected is the second electrode arranged in each row direction. Since they are electrically connected to each other, the redundancy of the common wiring can be increased. In addition, in this way, the first wiring and the second wiring of each common wiring are present in positions that partially and planarly overlap the two-terminal nonlinear element that does not contribute to display in the subpixel region. By arranging it at a position overlapping with the end of the second electrode or the other end, the first wiring and the second wiring of each common wiring function as a light shielding layer, and the aperture ratio is improved. be able to.

  In another aspect of the electro-optical device, the second electrode has a comb-tooth shape including a plurality of comb-tooth portions, and between the adjacent comb-tooth portions, the second electrode is connected to the first electrode. Gaps for generating the electric field are formed therebetween, and each of the gaps has a U-shaped planar shape.

  Here, when the corner of the gap located near the base of the comb-tooth portion is formed in a right-angled shape, the orientation control of the molecules (for example, liquid crystal molecules) constituting the electro-optic layer is made near the corner. It becomes difficult to cause light leakage due to an abnormal orientation of molecules constituting the electro-optic layer.

  In this respect, in this aspect, each of the gaps has a U-shaped planar shape, so that the corners of the gaps near the roots of the comb teeth have a curved shape. Thereby, in the vicinity of the corners of the gap, the alignment abnormality of the molecules constituting the electro-optic layer hardly occurs, and the occurrence of light leakage can be suppressed.

  In another aspect of the electro-optical device, the second electrode has a rectangular planar shape and a plurality of slits for generating the electric field between the first electrode and the second electrode. Each of the slits has a rounded quadrangular or elliptical planar shape.

  Here, when the corner of the slit is formed in a right-angled shape, it is difficult to control the orientation of molecules (for example, liquid crystal molecules) constituting the electro-optic layer near the corner, and the electro-optic layer is Light leakage due to an abnormal alignment of the constituent molecules tends to occur.

  In this regard, in this aspect, each of the slits has a rounded quadrangular or elliptical planar shape, so that the corners of the slit have a curved shape. Thereby, in the vicinity of the corner portion of the slit, it is difficult for the alignment abnormality of the molecules constituting the electro-optic layer to occur, and the occurrence of light leakage can be suppressed.

  In another aspect of the present invention, an electronic apparatus including the electro-optical device as a display unit can be configured.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In various embodiments of the present invention, the present invention is applied to a liquid crystal device as an example of an electro-optical device.

[First embodiment]
(Configuration of liquid crystal device)
First, with reference to FIG. 1, the planar configuration centering on the electrode and wiring configuration of the liquid crystal device according to the first embodiment of the present invention will be described.

  FIG. 1 is a plan view schematically showing an electrode and wiring configuration of the liquid crystal device according to the first embodiment. In FIG. 1, a color filter substrate 92 is disposed on the front side (observation side) of the paper surface, and an array substrate 91 is disposed on the back side of the paper surface. However, in the present invention, the arrangement relationship between the color filter substrate 92 and the array substrate 91 may be opposite to the configuration of FIG. In FIG. 1, regions corresponding to each of the three colored layers 4 of R (red), G (green), and B (blue) having a rectangular planar shape provided on the color filter substrate 92 side. The area overlapping with each pixel electrode 3 provided on the array substrate 91 side shows one sub-pixel area SG as a minimum unit of display and R, G, B arranged in one row and three columns. A region including the sub-pixel regions SG of the respective colors indicates one pixel region G. A region in which the sub pixel region SG or the pixel region G is arranged in a plurality of rows (horizontal direction on the paper surface: the same applies below) and a plurality of columns (the vertical direction on the paper surface: the same applies below) displays images such as characters, numbers, and figures. This is an effective display area V (area surrounded by a two-dot chain line). The area outside the effective display area V is a frame area 38 that does not contribute to display.

  The liquid crystal device 100 of the first embodiment is an active matrix driving method using a TFD element as an example of a two-terminal nonlinear element, and on the side of the array substrate 91 on which electrodes are formed, This is a FFS (Fringe Field Switching) type liquid crystal device as an example of a transverse electric field type, which controls the alignment of liquid crystal molecules by generating a fringe field (electric field) E in a direction substantially parallel to the substrate surface. For this reason, it is possible to obtain high transmittance and high viewing angle characteristics. The liquid crystal device 100 of the first embodiment is also a transmissive liquid crystal device.

  In the liquid crystal device 100 according to the first embodiment, an array substrate 91 and a color filter substrate 92 are bonded together by a frame-shaped sealing material 43, and the liquid crystal layer 15 is sealed in a region partitioned by the sealing material 43. Become.

  First, a planar configuration centering on the electrode and wiring configuration of the array substrate 91 will be described.

  The array substrate 91 mainly includes a plurality of data lines 32, a plurality of routing wirings 17, a plurality of common wirings 7, a plurality of TFD elements 21, a plurality of pixel electrodes 3, a plurality of common electrodes 9, a driver IC 41, and a plurality of external connections. Wiring 35 and FPC 42.

  The array substrate 91 has a protruding region 36 that extends outward from one side of the color filter substrate 92, and a driver IC 41 for driving liquid crystal is mounted on the protruding region 36. Each electrode (not shown) on the input side of the driver IC 41 is electrically connected to one end side of each external connection wiring 35, and the other end side of each external connection wiring 35 is each electrode (not shown) of the FPC 42. Abbreviation) and electrically connected. One end side (not shown) of the FPC 42 is electrically connected to an electronic device described later.

  Each data line 32 is formed to extend from the overhang area 36 to the effective display area V. One end of each data line 32 is electrically connected to each electrode (not shown) on the output side of the driver IC 41.

  Each lead-out wiring 17 is formed so as to extend from the overhang area 36 to the opposite side of the overhang area 36 in each frame area 38 located on both sides of the effective display area V. In a preferred example, each routing wiring 17 is preferably formed of any metal film of Cr (chromium), Ag (silver), and Al (aluminum) or a metal film including any of these. One end side of each routing wire 17 is electrically connected to each electrode (not shown) on the output side of the driver IC 41.

Each common wiring 7 has a U-shaped planar shape, a linear first wiring 7a extending in a direction orthogonal to the extending direction of the data line 32, and the extending of the first wiring 7a. The linear second wiring 7b extending in the same direction as the direction, and the third linear wiring 7c that electrically connects one end side of the first wiring 7a and one end side of the second wiring 7b. And comprising. Each common wiring 7 is provided corresponding to each sub pixel region SG group arranged in each row direction, and each third wiring 7c is electrically connected to the other end side of each routing wiring 17 through the contact hole 5a. Has been. In addition, the odd-numbered common wirings 7 corresponding to the address numbers G ₁ , G ₃ ... In addition, the even-numbered common wiring 7 corresponding to the address numbers G ₂ , G ₄ ... Is routed so as to extend from the right side 100R side of the liquid crystal device 100 to the left side 100L. ing.

  Each TFD element 21 is provided corresponding to each sub-pixel region SG and is electrically connected to each data line 32.

  Each pixel electrode 3 is provided corresponding to each of the sub-pixel regions SG and is electrically connected to each corresponding TFD element 21.

  Each common electrode 9 is provided corresponding to each of the sub-pixel regions SG and has a function of generating a fringe field (electric field) E with the corresponding pixel electrode 3.

  Next, the planar configuration of the color filter substrate 92 will be described.

  The color filter substrate 92 is a light-shielding layer (generally called “black matrix”, hereinafter simply abbreviated as “BM”) made of a black resin or a metal film that shields light, and three colors of R, G, and B Color layers 4R, 4G, 4B, and the like. In the following description, when referring to a colored layer regardless of color, it is simply referred to as “colored layer 4”, and when referring to a colored layer by distinguishing colors, it is referred to as “colored layer 4R” or the like.

  The BM is formed at a position that divides each sub-pixel region SG, a position corresponding to each TFD element 21, or the like. The colored layers 4 for each color of R, G, and B are provided corresponding to each of the sub-pixel regions SG. In the first embodiment, the colored layer 4 is arranged in the order of R, G, and B in the extending direction of the first wiring 7a and the second wiring 7b of the common wiring 7, but in particular in the arrangement order. There is no limitation.

  The liquid crystal device 100 having the above configuration is operated as follows.

First, by opening the switch of the TFD element 21 that is a switching element for a certain period, for example, address numbers S ₁ , S ₂ ,..., S _n (n: An image signal corresponding to (natural number) is written at a predetermined timing. The scanning signals corresponding to the address numbers G ₁ , G ₂ ,..., G _m (m: natural number) are pulsed at a predetermined timing to the routing wiring 17 and the common wiring 7 electrically connected to the routing wiring 17. Therefore, the lines are sequentially applied in this order. Thereby, the alignment state of the liquid crystal molecules of the liquid crystal layer 15 is controlled, and the display image is visually recognized by an observer.

(Pixel configuration)
Next, a pixel configuration of the liquid crystal device 100 according to the first embodiment will be described with reference to FIGS. 2 and 3.

  First, in FIG. 2, the pixel configuration including a plurality of sub-pixel regions SG in the array substrate 91 is as follows. FIG. 2 is a plan view showing a pixel configuration including a plurality of sub-pixel regions SG in the array substrate 91 according to the first embodiment.

  In the array substrate 91, between the sub-pixel regions SG adjacent to each other in the row direction, data lines 32 to which image signals are supplied are provided so as to extend in the column direction. Further, in the array substrate 91, each of the corresponding data lines 32 is electrically connected to the corner position of each sub-pixel region SG and in the vicinity of the boundary between the sub-pixels SG adjacent to each other in the column direction. TFD elements 21 are provided correspondingly, and each TFD element 21 is electrically connected to a rectangular pixel electrode 3 provided corresponding to each of the sub-pixel regions SG. The array substrate 91 has a common electrode 9 provided corresponding to each of the sub-pixel regions SG. Each common electrode 9 has a comb-tooth shape including a plurality of comb-tooth portions 9c, and overlaps each pixel electrode 3 in a planar manner. Each comb-tooth portion 9c extends in a direction intersecting the first wiring 7a and the second wiring 7b of each data line 32 and each common wiring 7, and between the adjacent comb-tooth portions 9c. A gap 9k for generating an electric field E in the extending direction of the data line 32 is formed between the pixel electrode 3 and the pixel electrode 3.

  The array substrate 91 has a common wiring 7 to which a scanning signal is supplied. Each common wiring 7 is formed of a light-shielding metal film. In a preferred example, the common wiring 7 is preferably formed of a metal film of Cr, Ag, or Al or a metal film including any one of them, as with each routing wiring 17. The first wiring 7a and the second wiring 7b of each common wiring 7 are formed between an arbitrary sub-pixel region SG and another sub-pixel region SG adjacent to the arbitrary sub-pixel region SG in the column direction. It is arranged near the boundary.

  In this example, the colored layers 4R, 4G, and 4B of R, G, and B, which are provided on the color filter substrate 92 side facing the array substrate 91, are disposed corresponding to the sub-pixels SG. And in this order with respect to the direction orthogonal to the extending direction of the data lines 32. Further, on the color filter substrate 92 side, between the sub-pixel regions SG adjacent to each other in the row direction, and in the column direction with respect to the first wires 7a of the common wires 7 and the first wires 7a. BMs are provided between the adjacent common wires 7 and the second wires 7b, and at positions corresponding to the TFD elements 21, respectively.

  Next, a cross-sectional configuration of the sub-pixel region SG will be described with reference to FIG. FIG. 3 is a cross-sectional view showing a cross-sectional configuration of the sub-pixel region SG along the cutting line AA ′ of FIG.

  The liquid crystal device 100 has a configuration in which a liquid crystal layer 15 exhibiting homogeneous alignment is sandwiched between an array substrate 91 disposed on the observation side and a color filter substrate 92 disposed opposite to the array substrate 91.

  First, the cross-sectional configuration of the array substrate 91 corresponding to FIG. 3 is as follows.

  The array substrate 91 includes a first substrate 1 made of a translucent material such as glass, and a plurality of components formed on the liquid crystal layer 15 side of the first substrate 1.

  Specifically, the TFD element 21 and the pixel electrode 3 electrically connected to the TFD element 21 are formed on the inner surface of the first substrate 1 on the liquid crystal layer 15 side.

  The TFD element 21 includes a first TFD element 21a and a second TFD element 21b. The first TFD element 21a and the second TFD element 21b are formed in an island shape, a first conductive film 322 containing tantalum as a main component and tungsten as an additive, and a surface of the first conductive film 322 And an insulating film 323 which is an anodic oxide film such as tantalum oxide, and second conductive films 316 and 336 formed on the surface and spaced apart from each other. Among them, the second conductive films 316 and 336 are obtained by patterning the same conductive film such as chromium, and the former second conductive film 316 is used for electrical connection with the pixel electrode 3. The latter second conductive film 336 is branched from the data line 32 in a T shape.

  Here, among the TFD elements 21, the first TFD element 21 a becomes the second conductive film 336 / insulating film 323 / first conductive film 322 in order from the data line 32 side. Because of the / insulator / metal structure, the current-voltage characteristics are nonlinear in both positive and negative directions. On the other hand, when viewed from the data line 32 side, the second TFD element 21b becomes a first conductive film 322 / insulating film 323 / second conductive film 316 in order, and is different from the first TFD element 21a. The structure is reversed. For this reason, the current-voltage characteristics of the second TFD element 21b are obtained by making the current-voltage characteristics of the first TFD element 21a point-symmetric with respect to the origin. As a result, since the TFD element 21 has a configuration in which two TFD elements are connected in series in opposite directions, the current-voltage nonlinear characteristic is symmetric in both positive and negative directions compared to the case where one TFD element is used. Will be.

  The pixel electrode 3 is formed of a transparent conductive film such as ITO (Indium-Tin-Oxide). On the inner surfaces of the TFD element 21, the pixel electrode 3, and the like, an insulating film 5 made of an insulating transparent material such as acrylic resin or silicon nitride is formed. A common electrode 9 and a common wiring 7 are formed on the inner surface of the insulating film 5. The common electrode 9 is formed of a transparent conductive film such as ITO. The common electrode 9 and the pixel electrode 3 overlap each other in a plane, and when a voltage is applied to the liquid crystal layer 15, an electric field E is formed between the pixel electrode 3 and the common electrode 9 through the gap 9k. Is distorted in an arch shape by the insulating film 5 and passes through the liquid crystal layer 15 to control the alignment of liquid crystal molecules. The first wiring 7a of the common wiring 7 exists at a position that partially and planarly overlaps with the TFD element 21 provided corresponding to the sub-pixel region SG, as indicated by a broken line region A1 in FIG. 2 or FIG. The second wiring 7b of the common wiring 7 is disposed at a position that overlaps with and directly connects to the end 9a of the common electrode 9 as shown in a broken line area A2 in FIG. 2 or FIG. And located on the side opposite to the end 9a of the common electrode 9 and partially and planarly overlaps with another TFD element 21 provided corresponding to the other sub-pixel region SG. The common electrode 9 is disposed so as to overlap with the other end 9b and to be directly connected. On the inner surfaces of the common wiring 7 and the common electrode 9, an alignment film 11 made of an organic material such as polyimide resin is formed. A polarizing plate 13 and a backlight 15 as a lighting device are arranged in this order on the outer surface of the array substrate 91 opposite to the liquid crystal layer 15 side. The backlight 15 is preferably a point light source such as an LED (Light Emitting Diode) or a combination of a linear light source such as a cold cathode fluorescent tube and a light guide plate.

  Next, the cross-sectional configuration of the color filter substrate 92 corresponding to FIG. 3 is as follows.

  The color filter substrate 92 includes a second substrate 2 formed of a light-transmitting material such as glass, and a plurality of components formed on the liquid crystal layer 15 side of the second substrate 2.

  Specifically, on the inner surface of the second substrate 2 on the liquid crystal layer 15 side, the colored layers 4R, 4G, and 4B (colored layer 4R in FIG. 3) of each color of R, G, and B, and light-shielding properties are provided. Each BM is formed.

  Each colored layer 4 is provided in a position corresponding to the pixel electrode 3 and the common electrode 9 in a plane, and BM is provided in a position corresponding to the TFD element 21. On each colored layer 4 and the inner surface of the BM, an overcoat layer 6 made of an insulating transparent material such as an acrylic resin is formed. The overcoat layer 6 has a function of protecting the colored layer 4 from corrosion and contamination by chemicals used during the manufacturing process of the color filter substrate 92. An alignment film 8 made of an organic material such as polyimide resin is formed on the inner surface of the overcoat layer 6. A polarizing plate 12 is disposed on the outer surface of the color filter substrate 92 opposite to the liquid crystal layer 15 side.

  In the liquid crystal device 100 having the above configuration, when it is driven, the alignment state of the liquid crystal molecules is controlled by a fringe field (electric field) E generated between the pixel electrode 3 and the common electrode 9, thereby performing color transmissive display. . At this time, the illumination light emitted from the backlight 15 travels along the path Lt shown in FIG. 3, passes through the pixel electrode 3, the common electrode 9, the colored layer 4, etc., and reaches the observer. In this case, the illumination light exhibits a predetermined hue and brightness by transmitting through the colored layer 4 and the like. Thus, a desired color display image is visually recognized by the observer.

  Next, operations and effects unique to the liquid crystal device 100 according to the first embodiment of the present invention compared to the comparative example will be described.

  First, with reference to FIG. 4, the planar configuration centering on the electrode and wiring configuration of the liquid crystal device 100x according to the comparative example will be described. FIG. 4 shows a planar configuration centering on the electrode and wiring configuration of the liquid crystal device 100x according to the comparative example corresponding to FIG.

  When the comparative example and the first embodiment are compared, the comparative example is different from the first embodiment in that the common wiring 7 is not provided and the configuration of the common electrode 9, and other than that is the same as the first embodiment. It is. Therefore, below, the same code | symbol is attached | subjected about the element same as 1st Embodiment, and the description is abbreviate | omitted.

  The common electrode 9x according to the comparative example is formed of a transparent conductive film such as ITO, is provided corresponding to each of the sub-pixel regions SG arranged in each row direction, and has the same comb-teeth shape as the common electrode 9 The first common electrode 9xa, the second common electrode 9xb connecting each of the first common electrodes 9xa, the one end side of the second common electrode 9xb near the routing wiring 17, and the contact hole 5a. And a third common electrode 9xc electrically connected to the routing wiring 17.

Each second common electrode 9xb provided corresponding to each row direction is in the vicinity of the boundary between an arbitrary subpixel region SG and another subpixel region SG adjacent to the subpixel region SG in the column direction. Correspondingly provided. Further, when the liquid crystal device 100x is viewed in a plan view, the odd-numbered common electrodes 9x corresponding to the address numbers G ₁ , G _3, ... The common electrodes 9x in the even-numbered rows corresponding to the address numbers G ₂ , G ₄ ... Extend from the right side 100R side of the liquid crystal device 100x as viewed from the right side 100R. It is routed to extend toward the side.

  The comparative example having the above configuration has the following problems.

  As described above, in the comparative example, since the common electrode 9x is formed of a transparent conductive film such as ITO having a high resistance value, the common electrode 9x is connected to each electrode (not shown) on the output side of the driver IC 41. The resistance value increases dramatically as the distance increases. As a result, even if data of the same gradation is written to each pixel electrode 3 arranged in each row direction, the side closer to each electrode (not shown) on the output side of the driver IC 41 (scan signal input side) A pixel electrode 3 positioned on the side closer to the output side of the driver IC 41 and a pixel electrode 3 positioned on the side farther from the electrodes (not shown) on the output side of the driver IC 41 (the side farther from the scanning signal input side) Thus, there is a problem that a difference occurs in the V (voltage) -T (transmittance) characteristics (hereinafter referred to as “VT characteristics”). In addition, the odd-row common electrodes 9x are routed so as to extend from the left side 100L side of the liquid crystal device 100x as viewed in the drawing to the right side 100R side of the drawing as well as the common electrodes of the even-numbered rows. 9x is routed so as to extend from the right side 100R side of the liquid crystal device 100x to the left side 100L of the paper surface, so that the display state is different for each row, and the stripes are streaked for each row. There is a problem that uneven display occurs.

  In response to such a problem, if the thickness of the common electrode 9x is increased (for example, about 1000 mm), the resistance value of the common electrode 9x can be lowered, so that such a problem can be improved. . However, in this case, the shape near the outer shape of the comb tooth portion of the first common electrode 9xa having the comb tooth shape becomes a precipitous shape, so the alignment of the liquid crystal molecules is not controlled near the outer shape of the comb tooth portion. As a result, a new problem arises in that light is lost and the contrast is reduced due to this. To solve this problem, it is possible to suppress the occurrence of liquid crystal molecule alignment anomaly by making the vicinity of the outer shape of the comb teeth portion, but the interval between adjacent comb teeth portions is as narrow as about 5 μm. Therefore, it is difficult to form the outer shape of the comb tooth portion in a tapered shape.

  Therefore, in consideration of these points, in the first embodiment of the present invention, each of the common electrodes 9 made of a transparent conductive film such as ITO arranged in each row direction is replaced with each of the common wires 7 made of a metal film. The first wiring 7a and the second wiring 7b are directly connected. Thereby, the resistance value of the connection structure between each common electrode 9 arranged in each row direction and each common wiring 7 can be lowered. As a result, the thickness of the common electrode 9 made of a transparent conductive film such as ITO can be reduced, and liquid crystal molecule alignment anomalies are less likely to occur near the outer shape of the comb-tooth portion 9c of the common electrode 9, and the vicinity of the outer shape. Can prevent leakage of light and improve contrast. This also causes a difference in VT characteristics between the pixel electrode 3 located on the side closer to the scanning signal input side and the pixel electrode 3 located on the side farther from the scanning signal input side. In addition to preventing the occurrence of striped display unevenness for each line, high display quality can be obtained.

  Here, FIG. 5 shows a comparison result of resistance values of the common electrode 9x according to the comparative example and the connection structure of the common electrode 9 and the common wiring 7 according to the first embodiment.

  In FIG. 5, the ITO common wiring corresponds to the common electrode 9x made of ITO according to the comparative example, and the ITO / Metal wiring corresponds to the common electrode 9 made of ITO and the metal film (Metal) according to the first embodiment. This corresponds to the connection structure of the common wiring 7 made of a film.

  Further, in the item of ITO common wiring shown in FIG. 5, “ITO film thickness” is the thickness of the common electrode 9x, “ITO sheet resistance” is the sheet resistance value of the common electrode 9x, and “horizontal dot pitch” "Is the length of the horizontal (row direction) period of the sub-pixel area SG, and" vertical dot pitch "is the length of the vertical (column direction) period of the sub-pixel area SG (= 3 times the horizontal dot pitch). In addition, “ITO wiring resistance” is the resistance value of one horizontal sub-pixel, and is the sum of the resistance values of the comb-shaped first common electrode 9xa and the second common electrode 9xb connecting it. “Number of dots” indicates the number of first common electrodes 9xa of the common electrodes 9x corresponding to one row.

  On the other hand, in the item of ITO / Metal wiring shown in FIG. 5, “ITO film thickness” indicates the thickness of the common electrode 9, “Metal film thickness” indicates the thickness of the common wiring 7, and “Metal sheet resistance”. "Is the sheet resistance value of the common wiring 7," Horizontal dot pitch "is the length of the horizontal (row direction) period of the sub-pixel region SG, and" Vertical dot pitch "is the vertical ( (Column direction) period length (= 3 times the horizontal dot pitch), “Metal wiring width” is the column direction length corresponding to the laminated portion of the connection structure, and “line resistance (1 “Dot”) indicates the resistance value of the metal wiring portion in one horizontal sub-pixel region SG, and “number of horizontal dots” indicates the number of common electrodes 9 corresponding to one row.

  From the above items, the total horizontal line resistance of the common electrode 9x corresponding to one row according to the comparative example is calculated as 14380 [Ω], while the total horizontal line resistance corresponding to one row according to the first embodiment is calculated. The line resistance {ITO + Metal (for two lines)} is the resistance 779 [Ω] of the horizontal line resistance (Metal: for two lines) of the common wiring 7 corresponding to one line and the common electrode 9 corresponding to one line. Is calculated as 739 [Ω] based on the resistance value 14380 [Ω] of the horizontal line resistance (ITO).

  From this calculation result, in the liquid crystal device 100 according to the first embodiment, if the common wiring 7 made of a metal film having a sheet resistance of 0.4 [Ω] is used, a 2-inch display panel (horizontal dot pitch: 59 [μm] × In the vertical dot pitch: 177 [μm], the number of dots: 528 × 220), the total horizontal line resistance {ITO + Metal (for two lines)} corresponding to one row corresponds to one row according to the comparative example. The total horizontal line resistance value of the common electrode 9x can be about 1/20 times. Therefore, the operational effects according to the first embodiment described above can be obtained.

  In the first embodiment, each common wiring 7 is formed of a light-shielding metal film, and an arbitrary sub-pixel region SG and another adjacent to the sub-pixel region SG in the column direction. Is arranged in the vicinity of the boundary with the sub-pixel region SG. Thereby, it is possible to improve the aperture ratio while causing each common wiring 7 to function as a light shielding layer.

  In the first embodiment, the first wiring 7a of the common wiring 7 is partially connected to the TFD element 21 provided corresponding to the sub-pixel region SG, as shown by a broken line region A1 in FIG. 2 or FIG. In addition, the second wiring 7b of the common wiring 7 is disposed at a position that overlaps with the end 9a of the common electrode 9 that exists in a planarly overlapping position and is directly connected to the end portion 9a. As shown by the broken line area A2 in FIG. 3, the TFD element 21 is located on the opposite side to the end 9a of the common electrode 9 and partially corresponds to the other TFD element 21 provided corresponding to the other subpixel area SG. In addition, it is disposed at a position that is directly connected to a position that overlaps with the other end portion 9b of the common electrode 9 that exists in a position overlapping in a plane.

  Thereby, each of the common electrodes 9 arranged in each row direction has a pair of first wiring 7a and second wiring 7b at the position of each end 9a or other end 9b of the common electrode 9. Connected directly. Therefore, each of the common electrodes 9 arranged in each row direction is compared with each of the common electrodes 9 arranged in each row direction, as compared with a connection structure in which each of the common electrodes 9 arranged in each row direction is directly connected to one metal wiring. The resistance value of the connection structure with the first wiring 7a and the second wiring 7b can be further reduced. In this case, even if one of the pair of the first wiring 7a and the second wiring 7b is disconnected, the wiring on the unbroken side is the common electrode 9 arranged in each row direction. Therefore, the redundancy of the common wiring 7 can be increased. Further, as shown in a region A3 in FIG. 2, the end portions 9a of the common electrodes 9 existing at positions where the respective common wirings 7 partially and planarly overlap the TFD elements 21 that do not contribute to display in the sub-pixel region SG. By arranging at a position overlapping with the other end portion 9b, it is possible to improve the aperture ratio while causing each common wiring 7 to function as a light shielding layer. Further, since each common wiring 7 functions as a light shielding layer, the width of the BM disposed between the sub-pixel regions SG adjacent to each other in the column direction can be reduced on the color filter substrate 92 side.

  In the liquid crystal device 100 according to the first embodiment, various wirings and electrodes are formed on the array substrate 91 side, and various wirings and electrodes are not formed on the color filter substrate 92 side. There is no need to establish vertical conduction between the side and the color filter substrate 92. This eliminates the need to mix a conductive member for vertical conduction in the sealing material 43. Therefore, the man-hour can be reduced by that amount, and the width of the sealing material 43 can be reduced, so that the liquid crystal device 100 having a small frame region 38 can be configured.

[Second Embodiment]
Next, the configuration of the liquid crystal device 200 according to the second embodiment of the present invention will be described with reference to FIGS. In the following, the same elements as those in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted.

  FIG. 6 shows a planar configuration centering on the electrode and wiring configuration of the liquid crystal device 200 according to the second embodiment of the present invention, corresponding to FIG. FIG. 7 is a plan view showing a pixel configuration including a plurality of sub-pixel regions SG in the array substrate 93 according to the second embodiment.

  When comparing the second embodiment with the first embodiment, the second embodiment is different from the first embodiment in that the common wiring does not have the second wiring 7b, and other than that in the first embodiment. It is the same.

That is, the common wiring 7x according to the second embodiment includes a linear first wiring 7a and a linear third wiring 7c that electrically connects one end side of the first wiring 7a. Each common wiring 7x is provided corresponding to each sub-pixel region SG group arranged in each row direction, and each third wiring 7c is electrically connected to the other end side of each routing wiring 17 through the contact hole 5a. Has been. Further, the odd-numbered common wiring 7x corresponding to the address numbers G ₁ , G ₃ ... Is routed so as to extend from the left side 200L side of the liquid crystal device 200 as viewed in the drawing to the right side 200R side of the drawing. In addition, the common lines 7x in the even-numbered rows corresponding to the address numbers G ₂ , G ₄ ... Are routed so as to extend from the right side 200R side of the liquid crystal device 200 as viewed in the drawing to the left side 200L side as viewed in the drawing. ing. The first wiring 7a of each common wiring 7x corresponds to the vicinity of the boundary between an arbitrary subpixel region SG and another subpixel region SG adjacent to the subpixel region SG in the column direction. Has been placed. Specifically, the first wiring 7a of the common wiring 7x is partially and planarly connected to the TFD element 21 provided corresponding to the sub-pixel region SG as shown in a region A4 of FIG. 6 or FIG. It is arranged at a position that is directly connected to a position that overlaps with the end portion 9a of the common electrode 9 that exists at the overlapping position.

  As described above, in the second embodiment of the present invention, each of the common electrodes 9 made of a transparent conductive film such as ITO arranged in each row direction is directly connected to the first wiring 7a of each common wiring 7x made of a metal film. It is connected. Thereby, the resistance value of the connection structure between each of the common electrodes 9 arranged in each row direction and each common wiring 7x can be lowered. As a result, the thickness of the common electrode 9 made of a transparent conductive film such as ITO can be reduced, and liquid crystal molecule alignment anomalies are less likely to occur near the outer shape of the comb-tooth portion 9c of the common electrode 9, and the vicinity of the outer shape. Can prevent leakage of light and improve contrast. This also causes a difference in VT characteristics between the pixel electrode 3 located on the side closer to the scanning signal input side and the pixel electrode 3 located on the side farther from the scanning signal input side. In addition to preventing the occurrence of striped display unevenness for each line, high display quality can be obtained.

  In this regard, the total lateral line resistance {ITO + Metal (one line)} corresponding to one row according to the second embodiment is the lateral line resistance of the common wiring 7x corresponding to one row from each item of FIG. Based on the resistance value 1558 [Ω] of (Metal: one line) and the resistance value 14380 [Ω] of the horizontal line resistance (ITO) of the common electrode 9 corresponding to one row, it is calculated as 1405 [Ω]. The

  From this calculation result, in the liquid crystal device 200 according to the second embodiment, if the common wiring 7 made of a metal film having a sheet resistance of 0.4 [Ω] is used, a 2-inch display panel (horizontal dot pitch: 59 [μm] × In the vertical dot pitch: 177 [μm], the number of dots: 528 × 220), the total horizontal line resistance {ITO + Metal (for one line)} corresponding to one row corresponds to one row according to the comparative example. The total horizontal line resistance value of the common electrode 9x can be about 1/10 times.

  In the second embodiment, the first wiring 7a of the common wiring 7x is partially and partially connected to the TFD element 21 provided corresponding to the sub-pixel region SG as shown in the region A4 of FIG. 6 or FIG. It is disposed at a position that overlaps with the end portion 9a of the common electrode 9 that exists at a position overlapping in a planar manner and at a position that is directly connected.

  Thereby, each of the common electrodes 9 arranged in each row direction is directly connected to the first wiring 7a of the single linear common wiring 7x at the position of each end 9a of the common electrode 9. The Therefore, the resistance value of the connection structure between each of the common electrodes 9 arranged in each row direction and each common wiring 7x can be lowered. Further, in this way, each common wiring 7x is disposed at a position overlapping with the end portion 9a of the common electrode 9 existing at a position partially and planarly overlapping with the TFD element 21 that does not contribute to display in the sub-pixel region SG. Thus, the aperture ratio can be improved while the common wiring 7x functions as a light shielding layer.

[Modification]
In the various embodiments described above, the common wiring 7 or 7x is formed so as to be stacked on the common electrode 9. On the contrary, in the present invention, the common electrode 9 is stacked on the common wiring 7 or 7x. You may form so that it may do.

  In the present invention, the gap 9k of the common electrode 9 preferably has a U-shaped planar shape.

  Here, when the corner portion of the gap 9k (corresponding to the portion of the broken line area A5) located near the root of the comb-tooth portion 9c is formed in a right-angled shape, the alignment control of liquid crystal molecules is performed in the vicinity of the corner portion. It becomes difficult to cause light leakage due to abnormal alignment of liquid crystal molecules.

  In this respect, in this embodiment, since the gap 9k has a U-shaped planar shape, the corner of the gap 9k near the root of the comb tooth portion 9c (the portion of the broken line area A5) is as shown in FIG. Moreover, it becomes a curved shape. Thereby, in the vicinity of the corners of the gap 9k, it becomes difficult for the alignment abnormality of the liquid crystal molecules to occur, and the occurrence of light leakage can be suppressed.

  Alternatively, in the present invention, as shown in FIG. 8B, the common electrode 9 has a rectangular planar shape and a plurality of slits 9s for generating an electric field E between the pixel electrode 3 and the common electrode 9. Each slit 9s preferably has a rounded quadrangular or elliptical planar shape.

  Here, when the corners of the slit 9s (corresponding to the broken line regions A6 and A7) are formed in a right-angled shape, it is difficult to control the alignment of the liquid crystal molecules in the vicinity of the corners. Light leakage due to orientation abnormality is likely to occur.

  In this respect, in this aspect, the slit 9s has a rounded quadrangular or elliptical planar shape, so that the corners of the slit 9s (parts of the broken line areas A6 and A7) have a curved shape. Thereby, in the vicinity of the corner portion of the slit 9s, it is difficult for liquid crystal molecule alignment abnormality to occur, and it is possible to suppress the occurrence of light leakage.

  In the various embodiments described above, the present invention is applied to a transmissive liquid crystal device. However, the present invention is not limited to this, and the present invention may be applied to a reflective or transflective liquid crystal device. Absent.

  In the present invention, various modifications can be made without departing from the spirit of the present invention.

[Electronics]
Next, specific examples of electronic devices to which the liquid crystal device 100 or 200 of the present invention can be applied will be described with reference to FIG.

  First, an example in which the liquid crystal device 100 or 200 of the present invention is applied to a display unit of a portable personal computer (so-called notebook personal computer) will be described. FIG. 9A is a perspective view showing the configuration of this personal computer. As shown in the figure, the personal computer 710 includes a main body 712 having a keyboard 711 and a display 713 to which the liquid crystal device 100 or 200 of the present invention is applied as a panel.

  Next, an example in which the liquid crystal device 100 or 200 of the present invention is applied to a display unit of a mobile phone will be described. FIG. 9B is a perspective view showing the configuration of this mobile phone. As shown in the figure, the mobile phone 720 includes a plurality of operation buttons 721, a receiving port 722, a transmitting port 723, and a display unit 724 to which the liquid crystal device 100 of the present invention is applied.

  In addition, as an electronic device to which the liquid crystal device 100 or 200 according to the embodiment of the present invention can be applied, in addition to the personal computer shown in FIG. 9A and the mobile phone shown in FIG. TV, viewfinder type / monitor direct view type video tape recorder, car navigation device, pager, electronic notebook, calculator, word processor, workstation, videophone, POS terminal, digital still camera, etc.

FIG. 2 is a plan view centering on electrodes and the like of the liquid crystal device according to the first embodiment of the present invention. FIG. 3 is a plan view showing a planar configuration of the array substrate according to the first embodiment. FIG. 3 is a cross-sectional view illustrating a cross-sectional configuration of a sub-pixel region of the liquid crystal device according to the first embodiment. The top view centering on the electrode etc. of the liquid crystal device which concerns on a comparative example. The table | surface which shows the relationship etc. of the resistance value of the common electrode of a comparative example, and the resistance value of the connection structure of the common electrode and common wiring which concern on the Example of this invention. The top view centering on the electrode etc. of the liquid crystal device which concerns on 2nd Embodiment of this invention. The top view which shows the plane structure of the array substrate which concerns on 2nd Embodiment. The top view which shows the structure of the common electrode which concerns on the various modifications of this invention. Examples of electronic devices to which the liquid crystal device of the present invention is applied are shown.

Explanation of symbols

  3 pixel electrode, 7 and 7x common wiring, 7a first wiring, 7b second wiring, 9 common electrode, 9a end, 9b other end, 9c comb tooth part, 9k gap, 9s slit, 15 liquid crystal layer , 21 TFD element, 91, 93 array substrate, 92 color filter substrate, 100, 200 liquid crystal device

Claims (8)

An electro-optic layer is sandwiched between the array substrate and the counter substrate,
In the region where the array substrate and the counter substrate overlap, a sub-pixel region arranged in a plurality of rows and a plurality of columns is provided,
The array substrate generates an electric field between a plurality of two-terminal nonlinear elements, a plurality of first electrodes electrically connected to each of the two-terminal nonlinear elements, and each of the first electrodes. A plurality of second electrodes to be generated, and each of the two-terminal nonlinear element, the first electrode, and the second electrode corresponds to each of the sub-pixel regions in the array substrate. Provided,
Each of the second electrodes is formed of a transparent conductive film, and each of the second electrodes arranged in each row direction is directly connected to each common wiring made of a metal film provided on the array substrate. An electro-optical device connected to the electro-optical device.   Each of the common wirings is formed of a light-shielding metal film, and in the vicinity of a boundary between the arbitrary sub-pixel region and another sub-pixel region adjacent to the sub-pixel region in the column direction The electro-optical device according to claim 1, wherein the electro-optical device is disposed on the electro-optical device.   Each of the common wirings has a linear shape extending in the row direction, and a position that partially and planarly overlaps the two-terminal nonlinear element provided corresponding to the arbitrary sub-pixel region 3. The electro-optical device according to claim 2, wherein the electro-optical device is disposed at a position that overlaps with an end of the second electrode that is present at a position directly connected to the second electrode. Each of the common wirings includes a linear first wiring and a linear second wiring extending in the same direction as the extending direction of the first wiring.
The position where the first wiring overlaps with the end portion of the second electrode existing at a position partially and planarly overlapped with the two-terminal nonlinear element provided corresponding to the arbitrary sub-pixel region It is arranged at a position that is directly connected to
The second wiring is located on the opposite side to the end of the second electrode, and partially with the other two-terminal nonlinear element provided corresponding to the other sub-pixel region. 3. The electro-optical device according to claim 2, wherein the electro-optical device is disposed at a position that overlaps with and directly connects to the other end of the second electrode that exists in a position overlapping in a plane. . The second electrode is made of ITO,
5. The common wiring according to claim 1, wherein each of the common wirings is formed of any one of Cr, Ag, and Al, or a metal film including any one of these. 5. Electro-optic device. The second electrode has a comb shape including a plurality of comb portions,
A gap for generating the electric field with the first electrode is formed between the adjacent comb tooth portions,
The electro-optical device according to claim 1, wherein each of the gaps has a U-shaped planar shape. The second electrode has a rectangular planar shape and a plurality of slits for generating the electric field with the first electrode,
The electro-optical device according to claim 1, wherein each of the slits has a rounded quadrangular or elliptical planar shape.   An electronic apparatus comprising the electro-optical device according to claim 1 as a display unit.

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