TW201243449A - Liquid crystal display device - Google Patents

Abstract

The present invention provides a liquid crystal display device with a circularly polarized VA mode, which can reduce costs and has excellent productivity, as well as an excellent gradation viewing angle from an intermediate gradation to a high gradation at a 45 DEG heading. According to the present invention, the liquid crystal display device is provided, in the following order, with: a first polarizer; a first λ/4 plate, a liquid crystal cell; a second λ/4 plate having an Nz coefficient different from that of the first λ/4 plate, and a second polarizer. If the heading of the absorption axis of the second polarizer is defined as 0 DEG, then with respect to the absorption axis of the second polarizer, the in-plane slow axis of the second λ/4 plate forms a substantially 45 DEG angle, the in-plane slow axis of the first λ/4 plate forms a substantially 135 DEG angle, and the absorption axis of the first polarizer forms a substantially 90 DEG angle. The display brightness is changed by changing the liquid crystal molecules in a liquid crystal layer from a substantially vertical alignment to a tilted alignment with respect to a substrate surface. The liquid crystal layer has four domains in which the liquid crystal molecules have a tilted alignment at a heading of 12.5 DEG to 32.5 DEG, 102.5 DEG to 122.5 DEG, 192.5 DEG to 212.5 DEG, and 282.5 DEG to 302.5 DEG, respectively.

Description

201243449 VI. Description of the Invention: [Technical Field of the Invention] The present invention relates to a liquid crystal display device. More specifically, the present invention relates to a liquid crystal display device using a VA (Vertical Alignment) mode having a circular polarizing plate. - [Prior Art] The liquid crystal display device is widely used as a display device of various information processing devices including a computer or a television. In particular, TFT (Thin Film 〇 Transistor) liquid crystal display devices (hereinafter also referred to as "TFT-LCD" (LCD, Liquid Crystal Display)) are widely used, and it is expected to further expand the market. Therefore, it is required to further improve the quality of the enamel. Hereinafter, the TFT-LCD will be described as an example. However, the present invention is not limited to the TFT-LCD, and can be applied to all liquid crystal display devices, and can be applied to, for example, a liquid crystal display device such as a simple matrix method or a plasma addressing method. ^ Up to now, the most widely used method in TFT-LCDs is a so-called TN (Twisted Nematic) mode in which liquid crystals having positive dielectric anisotropy are horizontally aligned between mutually opposing substrates. The liquid crystal display device of the TN mode is characterized in that the alignment direction of the liquid crystal molecules adjacent to one of the substrates is reversed by 90° with respect to the alignment direction of the liquid crystal molecules adjacent to the other substrate. Although such a TN mode liquid crystal display device has established a low-cost manufacturing technology and is mature in the industry, it is difficult to achieve a high contrast ratio. On the other hand, a so-called VA mode liquid crystal display device in which liquid crystal having negative dielectric anisotropy is vertically aligned between mutually opposing substrates is known. 163390.doc 201243449 In the VA mode liquid crystal display device, when no voltage is applied, since the liquid crystal molecules are aligned substantially perpendicular to the substrate surface, the liquid crystal cell hardly exhibits birefringence and optical rotation, and thus the light system The liquid crystal cell is passed through almost without changing its polarization state. Therefore, since the pair of polarizing elements (linear polarizing elements) are disposed above and below the liquid crystal cell such that their absorption axes are orthogonal to each other (hereinafter also referred to as "female polarizing element"), it is possible to achieve substantially complete voltage application. Black display. When a voltage equal to or higher than the threshold voltage is applied (hereinafter simply referred to as voltage application), the liquid crystal molecules are inclined and substantially parallel to the substrate, exhibiting a large birefringence, thereby realizing white display. Therefore, such a VA mode liquid crystal display device can easily achieve extremely high contrast. In such a VA mode liquid crystal display device, when the tilt direction of the liquid crystal molecules when the voltage is applied is unidirectional, the viewing angle characteristics of the liquid crystal display device are asymmetrical, and thus the following modes are widely used, that is, for example, The alignment direction of the liquid crystal molecules is divided into a plurality of alignment division type VA modes by the improvement of the structure of the pixel electrodes or the alignment control means such as the protrusions provided in the pixels. Furthermore, the regions in which the tilting directions of the liquid crystal molecules are different are also referred to as regions, and the mode of the split-divided type is also called the MVA mode (Multi_D〇main such as "AHgnment, multi-type vertical alignment mode"). In the secret mode, from the viewpoint of maximizing the transmittance of the white display state, it is usually set such that the drawing direction of the polarizing element and the tilting orientation of the liquid helium molecule when the voltage is applied are 45. The corner is 纟. The reason is as follows: The penetration rate of the double (four) medium in the middle of the part is the angle of the retardation axis of the birefringent medium of the polarizing element. (Unit: Department and I63390.doc 201243449

Sin2 (2a) is proportional. In a typical MVA mode, the tilting orientation of the liquid crystal molecules can be divided into 45. , 135. 225. 3 15 Four areas. That is to say, in the MVA mode which is easy to divide into four regions, the alignment of the SchHere or the direction of the undesired direction is observed in the vicinity of the boundary between the regions or the alignment control mechanism, thereby becoming worn. The original cause of the loss of permeability. In order to solve such a problem, a liquid crystal display device using a VA mode of a circular polarizing plate has been studied (for example, see Patent Document 1). According to such a liquid crystal display device, since the birefringence medium is sandwiched between the right and left circular polarizing plates which are orthogonal to each other, the transmittance does not depend on the angle between the axis of the polarizing element and the retardation axis of the birefringent medium. Therefore, even if the tilt angle of the liquid crystal molecules is not 45. , 135°, 225°, 315. As long as the slope of the liquid crystal molecules can be controlled, the required transmittance can be ensured. Therefore, for example, a circular protrusion may be disposed in the center of the pixel to tilt the liquid crystal molecules toward all directions, or the liquid crystal molecules may be tilted in a random orientation without completely controlling the tilt orientation. Again, this

VA In the manual, the VA mode with a circular polarizer is also called the circular polarization VA mode or the circular polarization mode. On the other hand, the VA mode using the linear polarizing plate is also referred to as a linear polarization VA mode or a linear polarization mode. Further, as is well known, a circular polarizing plate is typically constructed by a combination of a linear polarizing plate and a λ/4 plate. Further, it is known that since circularly polarized light has a property of alternating the left and right palms when reflecting on a mirror surface or the like, for example, when a left circular polarizing plate is disposed on a mirror surface to cause light to enter, a circular polarizing plate is penetrated and converted into a left circularly polarized light. The light is converted into a right circular polarized light by specular reflection, and the right circular polarized light cannot penetrate the above left circle 163390.doc 201243449 Polarizing plate 'so the result is that the circular polarizing plate has an anti-reflective optical function. It is known that the optical function of the anti-reflection of such a circular polarizing plate can prevent the reflection of the display device from being observed in a bright environment such as an outdoor environment, thereby improving the display device including the VA mode liquid crystal display device in a bright environment. The effect of contrast. Here, the above-mentioned unnecessary reflection is mainly referred to as reflection by a transparent wiring or a metal wiring of a TFT element existing inside the display device. If the unwanted reflection is not prevented, even if the display device that can achieve a substantially complete black display in a dark environment is viewed in a bright environment, the amount of light in the black display of the display device increases. The contrast is reduced. As described above, although the effect of improving the transmittance and preventing the unwanted reflection can be obtained by using the circularly polarized VA mode having a circular polarizing plate, in the liquid crystal display device of the previous circularly polarized VA mode, in the oblique viewing angle Low contrast 'Unable to obtain sufficient viewing angle characteristics, there is room for improvement in this area. Various techniques for improving the viewing angle characteristics using a birefringent layer (retardation film) have been proposed. For example, Patent Document 1 discloses the following (A) method. Patent Document 2 discloses the following method (B), and Patent Document 3 discloses the following (C) method, and Patent Document 4 discloses The following (D) method is disclosed in Non-Patent Document 1 by the following method (E). (A) A method of using two λ/4 plates satisfying the relationship of nx > ny > nz. (Β) Group & Two methods of satisfying the relationship of nx > ny > nz and one or two sheets of the second birefringent layer satisfying the relationship of nx < ny NZ are used. (C) A method of using two λ/4 plates satisfying the relationship of nx > nz > ny and a birefringent layer satisfying the relationship of nx = ny > nz in combination. 163390.doc 201243449 (d) In the method (c), one or two methods of λ/2 plates satisfying the relationship of nx > nz > ny are further used in combination. (Ε) Two uniaxial λ/4 plates (so-called human plates satisfying the relationship of nx > ny = nz), a birefringent layer satisfying the relationship of nx = ny > nz, and nx > nz > The method of the birefringent layer of the relationship. However, in the above methods (A), (B) and (C), there is still room for improvement in viewing angle characteristics. Further, in the above methods (C), (D) and (E), it is necessary to manufacture a biaxial phase difference which is difficult to manufacture and which satisfies the relationship of nx > nz > ny (satisfying the relationship of 0 < Νζ < 1) 〇 Membrane, there is room for improvement in this regard. Therefore, the inventors of the present invention have conducted various studies to solve the above problems, and have proposed the following (F) method (see Patent Document 5). (F) a combination of two persons/four plates, a third birefringent layer satisfying the relationship of ηχ=ηΥ>ηζ, a first birefringent layer satisfying the relationship of nx>ny and a relationship satisfying nx<nySnz The second method of birefringent layer. However, in the above (F) method, although the Nz coefficient (parameter indicating biaxiality) of two λ/4 plates is optimally designed, the improvement of the viewing angle characteristic is achieved, but two sheets are used. Under the design conditions of the universal biaxial λ/4 plate satisfying the relationship of nxh^nzW^1·0), there is room for improvement in the viewing angle characteristics. Therefore, the inventors further conducted a study of "results found" in making two λ/4 plates (first and second λ/4 plates) into a biaxial λ/4 satisfying the relationship of ηχ>η> After the board 'adjusts its Nz coefficient to be substantially the same' and at least one of the first λ/4 plate and the first polarizing element and between the second λ/4 plate and the second polarizing element satisfies ηχ<η0ηζ2 The birefringent layer of the relationship 'By 163390.doc 201243449 This makes it easy to manufacture a liquid crystal display device of a circularly polarized VA mode which can obtain a high contrast ratio in a wide viewing angle range, and has been patented in the prior application (refer to Patent Document 6) , 7). As described above, the inventors of the present invention have conducted various studies on the improvement of the viewing angle characteristic of the circularly polarized VA mode, and each of the above measures reduces the amount of light leakage in the black display in the oblique viewing angle in order to suppress the contrast angle dependence of the contrast, in other words, suppresses the low gray. View angle dependence at the order (low brightness). Therefore, the inventors of the present invention have repeatedly conducted research. As a result, it has been found that in the circularly polarized VA mode, when the orientation of the absorption axis of the polarization element arranged by the orthogonal polarization is defined as the orientation 0° and the orientation 90°, especially the orientation 45 . The viewing angle characteristics in the middle gray scale (middle brightness) to the still gray level (high brightness) are inferior to the linear polarization VA mode. That is, it can be seen that the orientation is 45. In addition, not only the viewing angle characteristics in the low gray level (hereinafter also referred to as "contrast viewing angle") are insufficient, but also the viewing angle characteristics in the middle gray level to the high gray level (hereinafter referred to as "gray level viewing angle"). full. Furthermore, the grayscale viewing angle can be expressed in the graph of the output grayness (transmission rate) in which the horizontal axis is the input gray scale and the vertical axis is the normalized output, and the input gray scale and the output luminance obtained by the measurement of the specific orientation are shown. The value of the line associated with the value (also known as the "gamma (gamma) curve"), which is consistent with the gamma curve obtained by the measurement of other orientations, is judged to be good or not, and is usually preferably positive in the display characteristics. The 7 curve (relative to the display screen in the normal direction) is as close as possible to the gamma curve in other directions. Furthermore, the inventors have found that the decrease in the contrast viewing angle and the decrease in the grayscale viewing angle occur in the same orientation, and thus in the front direction and other in the wider grayscale range from the low grayscale span and the high grayscale. Between the directions, the 535390.doc 201243449 horse curve is inconsistent, so the observer of the liquid crystal display device thinks that the display quality of the orientation 45° is extremely poor, and on the other hand, if the contrast viewing angle is lowered, the orientation and the grayscale viewing angle are lowered. Inconsistent, the level of comprehensive display quality will be improved. Further, the inventors have found that liquid crystal molecules are provided at 12 5 . ~32.5. The region of the azimuth oblique alignment and the liquid crystal molecules are at 1〇25. ~122·5. Azimuth tilt The area of alignment and liquid crystal molecules are at 192.5. ~212 5. The region of the azimuth tilt alignment and the liquid crystal molecules are at 282.5. ~302.5. The azimuth tilt alignment area improves the orientation 45 in the circularly polarized VA mode. The gray-scale viewing angle in the middle gray scale to the high gray scale is patented in the prior application (refer to Patent Document 8). Further, as a method for producing a circularly polarizing plate, there is proposed a method of producing a polarizing plate by a continuous winding technique using a λ/4 plate having an in-plane retardation axis in an oblique direction with respect to a machine direction (for example, reference) Non-patent document 2). According to this method, the Νζ coefficient of the λ/4 plate can be controlled between 丨i and 2. CITATION LIST Patent Literature Patent Literature 1: JP-A-2002-23449 Patent Document 2: Japanese Patent Laid-Open No. Hei. No. Hei. Patent Document 5: International Publication No. 2009/125515 Patent Document 6: International Publication No. 2010/087058 Patent Document 7: International Publication No. 2010/137372 No. 163390.doc 201243449 Patent Document 8: International Publication No. 2011/013399 Patent Document 9: Japanese Patent Laid-Open No. 2008-146003 Non-Patent Document Non-Patent Document 1: Ge Zhibing (Zhibing Ge), 6 others, "for Wide-View Circular Polarizers for Mobile Liquid Crystal Displays, IDRC08, 2008, p.266-268 Non-Patent Document 2: M. Hirota, 4 Name, "Retardation Films with In-Plane Oblique Slow-Axis", IDW, 08, 2008, ρ·1733-1736 Non-Patent Document 3: Takasaki Hiroshi, "Crystalization Optics", Senbei Published, 1975, p. 146-1 63 [Disclosure] Problems to be Solved by the Invention As described above, a circularly polarizing plate is typically a combination of a linear polarizing plate and a λ/4 plate. In this case, it is necessary to set the angle formed by the absorption axis of the linear polarizing plate and the in-plane slow axis of the λ/4 plate to be approximately 45°. Therefore, in recent years, from the viewpoint of improving productivity, the development has a λ/4 plate which is obliquely extended by a continuous winding technique, a uniaxially extending polarizing element, and a protective film (for example, TAC (Triacetyl Cellulose). A method in which a film is bonded to each other as a method of manufacturing a circularly polarizing plate. Further, a commercially available λ/4 plate having an Nz coefficient of approximately 1.6 and a circularly polarizing plate including the λ/4 plate are commercially available. However, in the case where the Nz coefficient of the λ/4 plate is large, there is a case where it is difficult to manufacture a circularly polarizing plate by a continuous winding technique. For example, it is difficult to manufacture a circularly polarizing plate comprising a λ/4 plate having an Nz coefficient greater than 2.〇, even by the technique described in Non-patent 163390.doc -10- 201243449. Therefore, in the case where the coefficient of the λ/4 plate is large, there is a possibility that the productivity of the circularly polarizing plate is lowered and the manufacturing cost is increased. Further, when a circular polarizing plate including a λ/4 plate having a large enthalpy coefficient is produced by a continuous winding technique, there is a possibility that the quality is lowered. In the technique of Patent Document 8, there are also 0 pieces according to the phase difference of the liquid crystal layer, the presence or absence of the third birefringent layer, and the phase difference of the third birefringent layer, and the first and second λ/ The coefficient of the 4 plate is set to be large. In this case, if the enthalpy coefficients of the first and second λ plates are substantially the same, the upper and lower circular polarizing plates may have a decrease in productivity, an increase in manufacturing cost, and a decrease in quality. For example, when two circular polarizing plates are produced by batch processing (single sheet processing), productivity is remarkably lowered. Further, the deterioration of the quality of the circularly polarizing plate causes a decrease in the viewing angle characteristic of the liquid crystal display device of the circularly polarized VA mode. Further, in the technique of Patent Document 8, when the third birefringent layer ◎ is not provided, it is necessary to compensate the liquid crystal layer by adjusting the Νζ coefficients of the first and second λ/4 plates. Further, since various surface treatment layers are usually provided on the circularly polarizing plate on the observation surface side of the liquid crystal cell, when the phase difference of the liquid crystal layer is changed, it is necessary to separately determine the phase difference of the liquid crystal layer and the type of the surface treatment layer. Reproduce two circular polarizers. As a result, there is no shortage of varieties and a large amount of production, and both cost and productivity are not optimistic. Moreover, it may also be a cause of hindering mass production. Therefore, in the technique of Patent Document 8, there is room for improvement in achieving cost reduction and productivity improvement. In addition, in the present specification, the circular 163390.doc -11 - 201243449 light plate disposed on the observation surface side of the liquid crystal cell is also referred to as a viewing surface side circular polarizing plate, and a circular polarizing plate disposed on the back side of the liquid crystal cell. It is called a back side circular polarizer. The present invention has been made in view of the above-described status quo, and an object of the present invention is to provide a cost-reducing and excellent productivity and an orientation of 45. A circularly polarized VA mode liquid crystal display device having an excellent gray-scale viewing angle in the middle gray scale to the high gray scale. MEANS FOR SOLVING THE PROBLEMS The present inventors have been able to reduce costs and productivity, and have an orientation of 45. A circularly polarized VA mode liquid crystal display device having excellent gray-scale viewing angle is subjected to various studies. The result focuses on a birefringent layer disposed between one of the orthogonal polarizing arrangements and the polarizing element (first and second polarizing elements). Phase difference condition. And found that 'the two λ/4 plates (the first and second λ/4 plates) required in the circular polarization VA mode are made to satisfy the relationship of ηχ>η^ηζ2 (in the present specification, "satisfying nx> ny2nz The birefringent layer of the relationship is defined as the first birefringent layer) after the biaxial λ/4 plate, so that the Nz coefficients thereof are different from each other, and the liquid crystal molecules are further set at 12.5. ~32.5. The area of the azimuth oblique alignment and the liquid crystal molecules are at 102.5. ~122.5. The azimuth oblique alignment region, the region where the liquid crystal molecules are obliquely aligned at 192.5° to 212.5°, and the region where the liquid crystal molecules are obliquely aligned at 282.5° to 302.5°, thereby improving the orientation 45 in the circularly polarized VA mode. The gray-scale view angle in the middle gray scale to the high gray scale. Further, the first double can be manufactured in a simple manner by using a material different from the biaxial retardation film controlled to nx > nz > ny (0< Nz < l) and having appropriate intrinsic birefringence. Refraction layer. Further, it has been found that even when the sum of the Nz coefficients of the first and second λ/4 plates is set to be large, 163390.doc -12-201243449 can be used in a more productive method (for example, using a continuous volume). A method of winding a technique is to manufacture a circular polarizing plate comprising a λ/4 plate having a smaller Nz coefficient. Further, a commercially available circular polarizing plate can also be used as a circular polarizing plate including a λ/4 plate having a smaller enthalpy coefficient. Further, it has been found that since the νζ coefficients of the first and second λ/4 plates can be individually adjusted, it is possible to respond flexibly to the design change with respect to the change in the phase difference of the liquid crystal layer and the type change of the surface treatment layer. More specifically, for example, when the phase difference of the liquid crystal layer is changed, the compensation of the liquid crystal layer can be performed by adjusting only the 0 Νζ coefficient of one of the λ/4 plates. Moreover, in this case, the third birefringence having an appropriate phase difference can also be set by adjusting only the Νζ coefficient of one of the λ/4 plates and further on the circular polarizing plate including the λ/4 plate. Layer, and compensation for the liquid crystal layer. That is, the change in the phase difference of the liquid crystal layer can be dealt with only by designing one of the circular polarizers. As a result of the above, it has been thought that the above problems can be satisfactorily solved, and the present invention has been achieved. That is, a certain aspect of the present invention is a liquid crystal display device (hereinafter also referred to as a liquid crystal display device of the present invention), in which a birefringent layer satisfying the relationship of ηχ>咐岐 is defined as the first birefringent layer. Sequentially: the first polarizing element; the -λ/4 plate's in-plane phase difference is adjusted to λ/4; the liquid crystal is singular, which contains one of the opposite directions *jc a + on the substrate and sandwiched Between the pair of substrates - the liquid crystal layer; the second k/4 plate, the JL ancient: , has a different Nz series - number than the first λ / 4 plate of the s Xuan and the in-plane phase difference is temporarily adjusted η拉碉I is λ/4, and a second polarizing element; and the first and second λ/4 plates are first-connected birefringent layers, and the orientation of the absorption axis of the second polarizing element is defined Α η. When the main _ ^ is 0, the in-plane slow axis of the second λ/4 plate is approximately 45. From the angle, the in-plane slow axis of the first λ/4 plate is approximately 135. From the angle, the first polarizing element 1 has a dry and a retracted axis of approximately 9 turns. In view of the above, the 163390.doc -13-201243449 liquid crystal display device displays the brightness change by changing the state in which the liquid crystal molecules in the liquid crystal layer are substantially perpendicularly aligned with respect to the substrate surface to the state of the oblique alignment. The layer has liquid crystal molecules at 12.5. ~32 5. The area in which the orientation is obliquely aligned and the liquid crystal molecules are at 102·5. ~122 5. The region of the azimuth oblique alignment and the liquid crystal molecules are at 192.5. ~212 5. The area of the azimuth tilt alignment and the liquid crystal molecules are at 282.5. ~302.5. The area of the azimuth tilt alignment. In the present specification, the "orientation" means an orientation in a direction parallel to the substrate surface of the liquid crystal cell, and is taken up to 36 〇. The inclination angle with respect to the normal direction of the substrate surface of the liquid crystal unit is not considered. The angle of inclination with respect to the normal direction of the substrate surface of the liquid crystal cell is referred to as "polar angle". The polar angle is taken ~. 1 is a view in which the orientation of the absorption axis of the first polarizing element is not set to the X axis, the axis orthogonal to the in-plane direction with respect to the Χ axis is set to the ¥ axis, and the axis is outward in the out-of-plane direction with respect to the X-axis. When the orthogonal axis is set as the ζ axis, the azimuth angle # and the polar angle with respect to the tilting direction of the liquid crystal molecules

The liquid crystal display device of the present invention is displayed by a so-called MVA mode (multi-domain type VA mode). In the MVA mode, for example, by providing a slit (electrode slit) formed in a pixel electrode and/or a common electrode for applying a liquid to a liquid crystal layer, and a dielectric protrusion formed in the pixel, The control mechanism' divides the tilt of the liquid crystal molecules when the voltage is applied into a plurality of pixels. Thereby, the symmetry of the tilt orientation of the liquid crystal molecules can be improved, whereby the viewing angle characteristics of the liquid crystal display device can be improved. Further, the liquid crystal display device of the present invention is also displayed by a so-called circularly polarized va mode. It is not necessary to set the axial orientation of the optical element and the tilting orientation of the liquid crystal molecules when applying the linear polarizing plate as in the typical Wei mode. 163390.doc •14·201243449 At an angle of 45° to maximize the white display state. Transmittance. Therefore, even liquid crystal molecules are formed at 12.5. ~32.5° azimuth oblique alignment area, liquid crystal molecules at 102.5. ~122.5. The region of the azimuth oblique alignment, the region where the liquid crystal molecules are obliquely aligned at 192.5° to 212.5°, and the region where the liquid crystal molecules are obliquely aligned at 282.5° to 302.5°, in principle, are displayed by linear polarization mode. Generally, the penetration rate of the white display state does not decrease.

D

In the liquid crystal display device of the present invention, the term "region" refers to a region in a pixel in which the tilt angle of the liquid crystal molecules is substantially the same as the voltage applied to the liquid crystal layer. The regions including the liquid crystal molecules having different polar angles are included in the same region if the tilting directions are substantially the same. The liquid crystal display device of the present invention is not particularly limited by other members as long as it includes the first polarizing element, the first λ/4 plate, the liquid crystal cell, the second λ/4 plate, and the second polarizing element as components. From the viewpoint of achieving a high contrast ratio in a wide viewing angle range, it is preferable to use (1) between the first λ/4 plate and the first polarizing element and further including a second birefringent layer. And the in-plane phase axis of the second birefringent layer is substantially orthogonal to the absorption axis of the first polarizing element. (7) further comprising the first λ/4 plate and the first polarizing element : a second birefringent layer, and a second second birefringent layer between the second plate and the second polarizing member, and the inward surface of the first second birefringent layer The phase infeed axis is substantially orthogonal to the absorption axis of the first polarizing element, and the in-plane axis of the second second birefringent layer is substantially orthogonal to the absorption axis of the second polarizing element. 163390.doc 15 201243449 In addition, in the present specification, the term "polarized element" means that natural light (unpolarized light), partial polarized light or polarized light is converted into linearly polarized light, that is, self-natural light (no polarized light), partially polarized light or polarized light. A component that functions as a linear polarizer is synonymous with a polarizing film. Furthermore, in the present specification, the contrast of the polarizing plate including the polarizing element is not necessarily infinite, and may be 5 Å or more (preferably 10,000 or more), which means "birefringent layer", which means optical anisotropy. The layer is equivalent to the retardation film, the retardation film, the optically anisotropic layer, and the birefringent medium. From the viewpoint of sufficiently exerting the effect of the liquid crystal display device of the present invention, the "birefringent layer" in the present specification is It is assumed that at least one of the absolute values of the in-plane retardation R and the thickness direction retardation Rth described below has a value of 10 nm or more, and preferably has a value of 2 〇 nm or more. In the present specification, the "first birefringent layer" means a birefringent layer satisfying the relationship of nx > npnz, and the "second birefringent layer" means a birefringent layer satisfying the relationship of nxcny^nz. The 叮 表 表 表 表 表 表 表 550 550 550 550 550 550 550 550 550 550 550 550 550 550 550 550 550 550 550 550 550 550 550 550 550 550 550 550 550 550 550 550 550 550 550 550 550 550 550 550 Isotropic film The absolute value of the internal phase difference R and the thickness direction phase difference Rth has a value of 1 〇 nm or less, and preferably has a value of 5 nm or less. In the present specification, 'the in-plane phase difference R' is The principal refractive index of the in-plane direction of the birefringent layer (which also includes the liquid crystal cell or the λ/4 plate) is defined as a heart and ny, and the principal refractive index of the out-of-plane direction (thickness direction) is defined as ηζ, and the birefringent layer is When the thickness is defined as d, the in-plane phase difference (unit: nm, absolute value) defined by R = |nx_ny|xd. In contrast, "thickness direction phase difference 163390.doc -16- 201243449

Rth" is an out-of-plane (thickness direction) phase difference (unit: nm) defined by Rth = (nz - (nx + ny) / 2) xd. The "λ/4 plate (which also includes the λ/4 plate whose in-plane phase difference is adjusted to λ/4.)" means that the light is at least 1/4 wavelength with respect to the wavelength of 55 瓜 melon. The optically anisotropic birefringent layer of 137.5 nm, which is larger than I15 nm and smaller than 160 nm, is synonymous with the λ/4 phase 'difference film and the λ/4 phase difference plate. The "in-plane retardation axis (phase advance axis)" is defined by redefining the larger of the in-plane principal refractive indices nx and 〇 为 as ns' and redefining the smaller one as the main refractive index. Ns(nf) corresponds to the direction of the dielectric main axis (χ axis or y-axis direction). Further, the "Nz coefficient" indicates the degree of biaxiality of the birefringent layer defined by Nz = (ns_nz) / (ns nf) The parameters. Further, unless otherwise specified, the measurement wavelength of the main refractive index or the phase difference in the present specification is 550 nm. Further, even if the birefringent layer having the same Nz coefficient has an average refractive index = (nx + ny + nz) / 3 of the birefringent layer, the effective phase difference of the birefringent layer is relative to the self due to the influence of the refraction angle. The oblique incidence is different, which leads to a complicated design policy. In order to avoid this problem, unless otherwise stated in the specification, the Nz coefficient is calculated by uniformly calculating the average refractive index of each birefringent layer to 1.5. For a double-refractive layer whose actual average refractive index is not 15, it is also assumed to be converted by an average refractive index of 15. Further, the same processing is performed for the phase difference Rth in the thickness direction. In the aspect of the above (2), the Nz coefficient of the first first birefringent layer and the Nz coefficient of the second second birefringent layer may be appropriately set, respectively, but the first one is preferably The Nz coefficient of the second birefringent layer and the Nz coefficient of the second second birefringent layer are substantially identical to each other. 163390.doc -17- 201243449 'Also, the in-plane phase difference of the first second birefringent layer and the in-plane phase difference of the second second birefringent layer may be appropriately set, respectively, but it is preferably The in-plane phase difference of the first second birefringent layer is substantially the same as the in-plane phase difference of the second second birefringent layer. Hereinafter, in the present specification, only the form in which the coefficient and the in-plane phase difference of the second second birefringent layer are substantially the same as the Nz coefficient and the in-plane phase difference of the first second birefringent layer are described. In the present specification, the Nz coefficient of the human/bucket plate is different from the Nz coefficient of the second χ/4 plate, and the term 'is a case where the difference between the Νζ coefficients is 〇1 or more, and preferably 0.3 or more. The phrase "the coefficient of the first second birefringent layer is substantially the same as the coefficient of the second second birefringent layer" means that the difference between the Nz coefficients is less than 0.1, preferably less than 〇 .〇5. The "in-plane phase difference of the first second birefringent layer is substantially the same as the in-plane phase difference of the second second birefringent layer", which means that the difference in the in-plane phase difference is less than 2 〇 (10). 'It is preferably less than 10 nm. The "in-plane slow axis of the second λ/4 plate is approximately 45." means that the angle between the in-plane slow axis of the second person/four plate and the absorption axis of the second polarizing element is 4 〇~5〇. You can't be 45. . That is, the in-plane slow phase axis of the second λ/4 plate is facilitated. The relative angle of the absorption axes of the first polarized pieces is not absolutely "in the case of the surface of the first λ/4 plate and the in-plane phase of the second person/four plate. Orthogonally, it is sufficient to prevent light leakage with respect to the substrate direction ==3⁄4. On the other hand, in terms of the improvement of the anti-reflection function or the β-rate, the above relative angle is 45. The effect is that "the in-plane slow axis of the first λ/4 plate is approximately 163390.doc 18·201243449 angle", which means that it is located at approximately 45. In the plane of the second λ/4 plate of the orientation, the phase of the slow phase axis of the late phase axis 1-1/, λ/4 plate is 88~92. That is, 尤 is especially good for 9〇〇. Therefore, "the angle of the absorption axis of a polarizing element is substantially 90. The angle" means that the absorption axis of the second polarizing element and the absorption axis of the first polarizing element are at an angle of 88 to 92. It can be, especially 90. . The "in-plane advancing axis of the (second or first) second birefringent layer is substantially orthogonal to the absorption axis of the (first or first) polarizing element" means the second birefringent layer

The angle between the inner phase axis and the absorption axis of the polarizing element is 88 to 92. That is, it is especially good. . As described below, since the second birefringent layer is used to control the change in the polarization state of the display light, thereby reducing the light leakage in the black display state over a wider viewing angle range and achieving a higher contrast ratio, the above (1) Preferably, the form is first except that the second birefringent layer, the first λ/4 plate (the first birefringent layer), the liquid crystal cell, and the second λ/4 plate (the first birefringent layer) are included. The form of the birefringent medium is not included between the polarizing element and the second polarizing element. Moreover, from the viewpoint of reducing the number of birefringent layers used for the liquid crystal display device and reducing the cost, it is preferable to include the first polarizing element, the second birefringent layer, and the first λ/4 plate (the first type The refractive layer), the liquid crystal cell, the second λ/4 plate (the second birefringent layer), and the second polarizing element do not include a birefringent medium in the liquid crystal display device. On the other hand, in addition to the first polarizing element, the second birefringent layer, the first λ/4 plate (the first birefringent layer), the liquid crystal cell, and the second λ/4 plate (the first birefringent layer) In addition to the second polarizing element, a birefringent medium 'for example' may be added to the liquid crystal display device, and a λ/2 plate having an in-plane retardation adjusted to λ/2 may be added to the liquid crystal display device to 163390.doc -19- 201243449 Adjust the wavelength dispersion of the oil-reducing layer of the birefringent layer. Further, the form of the above (2) is preferably a first birefringent layer including a first first-upper a, a first λ/4 plate (first birefringent layer), a liquid rafting unit 7^, and a second In addition to the λ/4 plate (the first birefringent layer) and the second second birefringent layer, the form of the medium is refracted between the first polarizing element and the second polarizing element. From the viewpoint of reducing the number of birefringent layers used for the liquid crystal display device and reducing the cost, it is more preferable to include the first polarizing element, the second second birefringent layer, and the first λ/4 plate (the first type) The birefringent layer), the liquid crystal cell, the second λ/4 plate (first birefringent layer), the second first birefringent layer, and the second polarizing element do not include a birefringent medium in the liquid crystal display device. In addition to the form of the above (1), in addition to the first-polarized S piece, the first second birefringent layer, the -λ/4 plate (first birefringent layer), the liquid crystal cell, and the second λ/4 plate (First Birefringent Layer) In addition to the first birefringent layer and the second polarizing element, a birefringent medium may be added to the liquid crystal display device. For example, the in-plane retardation system may be adjusted to λ/2. The /2 plate is attached to the liquid crystal display device to adjust the wavelength dispersion of the birefringent layer or the like. Further, the inventors have found that the reason for obstructing the complete black display differs depending on the orientation, and it is found that the birefringent layer satisfying the relationship between ηχ and ny>nz is disposed between the first and second λ/4 plates. (In the present specification, "a birefringent layer satisfying the relationship between nx and ny" is defined as a third birefringent layer"', and phase difference compensation with respect to a plurality of directions can be performed. In setting the second birefringent layer, first, the orientation 0 can be adjusted by adjusting the phase difference of the third birefringent layer. The condition of the phase difference compensation is optimized, and then, by appropriately configuring the phase difference of the second birefringent layer, 163390.doc -20-201243449 does not change the orientation 〇. The optimization of the phase difference compensation in the condition will be azimuth 45. The condition of the phase difference compensation is optimized, thereby reducing the light leakage in the obliquely black display state in a wider orientation. As a result, a higher contrast ratio in a wider range of viewing angles can be achieved in both the azimuth and the polar angle. Further, a third birefringence can be produced in a simple manner by using a material different from the biaxial retardation film controlled to nx >nz>ny (0<Nz<l) and having appropriate intrinsic birefringence. Floor. That is, the liquid crystal display device of the present invention may further include at least one layer between the first λ/4 plate and the liquid crystal cell and at least one of the liquid crystal cell and the second λ/4 plate. A birefringent layer. In the case where the average of the Νζ coefficients of the first λ/4 plate and the second λ/4 plate is less than 2.00, the third birefringent layer described above can be preferably used. Preferably, the third birefringent layer is disposed adjacent to the liquid crystal cell. Here, the "adjacent arrangement" means that no birefringent medium is provided between the third birefringent layer and the liquid crystal cell, and includes, for example, a third birefringent layer and a liquid crystal cell. The shape of the same film. Further, in the case where a plurality of third birefringent layers are provided, it is preferable that at least one of the plurality of third birefringent layers is disposed adjacent to the liquid crystal cell, and each of the third birefringent layers is mutually connected to each other. The configuration of the adjacent configuration. Furthermore, nxf in the so-called third birefringent layer: 5ny, in other words, lnx_ny丨 and 〇, specifically, the in-plane phase difference R is called nx-ny|xd, which is less than 2〇nm. It is preferably less than 1 〇 nm. Therefore, the third birefringent layer also includes a birefringent layer satisfying the relationship of nx = ny > nz. The above-mentioned third birefringent layer includes a plurality of layers or only one layer, as long as it is disposed on the inner side of the first λ/4 plate and the second λ/4 plate (the liquid crystal cell side) of the upper 163390.doc -21 - 201243449 The sum of the phase differences in the thickness direction is the same, and the characteristics of the transmitted light intensity of the liquid crystal display device are identical in principle. Further, in the case where the liquid crystal display device does not actually include the third birefringent layer, it is also assumed that the third birefringent layer having a phase difference in the thickness direction is zero, and there is no problem in principle. Therefore, in the present specification, as the liquid crystal display device of the present invention, only a liquid crystal display in which a third birefringent layer is disposed between the first λ/4 plate and the liquid crystal cell will be described. Device to simplify the description. The polarizing element is typically one in which an anisotropic material such as an iodine complex having dichroic properties is adsorbed and applied to a polyvinyl alcohol (PVA, P〇ly Alcohol) film. Usually, in order to ensure mechanical strength or moist heat resistance, a protective film such as a triacetyl cellulose (TAC) film is laminated on both sides of the PVA film, but it is referred to in the present specification unless otherwise specified. In the case of "polarizing element", it means only a member that does not include a protective film and has a polarizing function. Furthermore, any one of the first and second polarizers is a polarizer (a polarizing element on the back side) or an analyzer (a polarizing element on the side of the observation surface), and the characteristics of the transmitted light intensity of the liquid crystal display device are completely in principle. the same. Namely, any of the first and second first birefringent layers may be provided on the observation surface side of the liquid crystal cell. However, in general, the observation side circular polarizing plate must be made of a plurality of different types of surface treatment layers depending on the actual application and the requirements from the user, so that it is expected to be more productive than the back side circular polarizing plate. The composition of the grass. On the other hand, since the back side circular polarizer usually does not require surface treatment, only 163390.doc -22- 201243449 can be manufactured. Therefore, even if the composition of the back side circular polarizing plate is slightly complicated, the influence on mass production is relatively small. In this case, it is preferable to use a person with a larger Nz coefficient/4 plates (= more difficult to utilize productivity) λ/4 plate which is disposed on the back side of the liquid crystal cell and has a smaller Νζ coefficient (= Manufactured by a manufacturer with higher productivity - 4 plates) It is disposed on the observation surface side of the liquid crystal cell. From the same viewpoint, it is preferable to arrange the second birefringent layer and the person/4 plate having a larger coefficient to be disposed on the back side of the liquid crystal cell. Further, it is more preferable to arrange the third double-folding layer only on the back side of the liquid crystal cell. In the configuration including the third birefringent layer, when the phase difference (?nd) of the liquid crystal layer is changed, the phase difference of the third birefringent layer is usually adjusted to cope with it. However, when the third birefringent layer is disposed on the side circular polarizing plate of the observation surface, the problem of an increase in variety due to the difference in surface treatment described above is further aggravated. Therefore, the third birefringent layer is preferably disposed on the back side circular polarizing plate. For example, when five kinds of surface treatments and four kinds of liquid crystal layers are in phase difference, if the third birefringent layer is disposed on the observation surface side circular polarizing plate, the observation side circular polarizing plate is 5x4=20 varieties. , the back side of the circular polarizer is! For each variety, it is necessary to have a dozen of 00 kinds of circular polarizers. On the other hand, when the third birefringent layer is disposed on the back side circular polarizing plate, the observation surface side circular polarizing plate has five varieties, and the back side circular polarizing plate has four varieties. Therefore, only nine varieties are prepared in total. The circular polarizing plate can be used. From this point of view, it is preferable that the first and second first birefringent layers have a larger Νζ coefficient on the back side of the liquid crystal cell. Further, 163390.doc • 23· 201243449 when the Nz coefficient of the first λ/4 plate is greater than the Nz coefficient of the second λ/4 plate, the liquid crystal display device of the present invention is preferably the second polarizing element. The observation side further includes a surface treatment layer. In the above aspect (1), the second birefringent layer is preferably disposed on the back side of the liquid crystal cell. In this case, it is preferable that the Nz coefficient of the first λ/4 plate is larger than the second λ/ The Nz coefficient of the four plates, and the second birefringent layer and the first λ/4 plate are disposed on the back side of the liquid crystal cell. Further, in the aspect of the above (1), the at least one third birefringent layer is preferably disposed on the back side of the liquid crystal cell. In this case, it is preferable that the Nz coefficient of the first λ/4 plate is larger than the above. The Nz coefficient of the second λ/4 plate, and the second birefringent layer, the first λ/4 plate, and the at least one third birefringent layer are disposed on the back side of the liquid crystal cell. In the above aspect (2), the at least one third birefringent layer is preferably disposed on the back side of the liquid crystal cell. In this case, it is preferable that the Nz coefficient of the first λ/4 plate is greater than the second The Nz coefficient of the λ/4 plate, and the first λ/4 plate and the at least one layer of the third birefringent layer are disposed on the back side of the liquid crystal cell. Hereinafter, unless otherwise stated, only the liquid crystal display device in which the first polarizing element is a polarizer will be described in the present specification, and the description will be simplified. The liquid crystal cell includes a pair of substrates facing each other and a liquid crystal layer sandwiched between the pair of substrates. The liquid crystal cell of the present invention is a multi-domain VA (MVA) mode liquid crystal which is a type of vertical alignment (VA) mode in which liquid crystal molecules in a liquid crystal layer are aligned to be substantially perpendicular to a substrate surface. unit. MVA mode can also be Continuous Pinwheel Alignment (CPA, continuous flame-like alignment) mode 163390.doc -24- 201243449, Patterned VA (PVA, patterned vertical alignment) mode, Biased VA (BVA, biased vertical alignment) mode, Reverse TN (RTN, reverse twist nematic) mode and In Plane Switching-VA (IPS-VA, coplanar switching - vertical alignment) mode. In the present specification, "aligning the liquid crystal molecules to be substantially perpendicular to the substrate surface" means that the average pretilt angle of the liquid crystal molecules is 80. More than that. The liquid crystal display device of the present invention includes a first first birefringent layer (first λ/4 plate) and in-plane with an in-plane retardation adjusted to λ/4 between the first polarizing element and the second polarizing element. The second first type of birefringent layer (second λ/4 plate) whose phase difference is adjusted to λ/4 may further include a second birefringent layer and/or a third birefringent layer, but From the viewpoint of further reducing the cost, it is preferable that a third birefringent layer is not provided between the first polarizing element and the second polarizing element. In the case where the third birefringent layer is not included, in the case of changing the phase difference (And) of the liquid crystal layer, it is preferable to adjust the Νζ coefficient of the λ/4 plate having a larger Νζ coefficient. In this way, a plurality of liquid crystal cells having different phase differences of the liquid crystal layers can be used in combination with a λ/4 plate having a smaller enthalpy coefficient (= λ/4 plate which is more easily manufactured by a highly productive manufacturing method). Circular polarizer. The Νζ coefficient of the first λ/4 plate and the Νζ coefficient of the second λ/4 plate may be appropriately set, respectively, but is preferably greater than 1. Moreover, it is more preferable that one of the first λ/4 plate and the second λ/4 plate has a Νζ coefficient of 2 or more, and the other of the first λ/4 plate and the second λ/4 plate The coefficient of the enthalpy is 1 or more and less than 2. Thereby, a λ/4 plate having a smaller enthalpy coefficient can be produced by a technique which is particularly excellent in productivity (for example, the technique described in Non-Patent Document 2). Further, since 163390.doc -25-201243449, a commercially available λ/4 plate (general product) having an Nz coefficient of approximately 1.6 can be used as the λ/4 plate having a smaller enthalpy coefficient, and thus in the form of the above (1) Among them, a commercially available circular polarizing plate can be used as a circular polarizing plate including a λ/4 plate having a smaller Nz coefficient. Further, a plurality of kinds of circular polarizing plates which are subjected to surface treatments which are different from each other are commercially available. Thus, by setting the Nz coefficient of one of the λ/4 plates to 1 or more and less than 2, the cost of the circularly polarizing plate including the λ/4 plate can be drastically reduced, and the productivity can be remarkably improved. Further, by setting the Nz coefficient of one of the λ/4 plates to 1 or more and less than 2, and setting the Nz coefficient of the other λ/4 plate to 2 or more, the first and second λ/ can be easily performed. The average value Nzq of the Nz coefficients of the four plates is set to the preferred range described below. Further, in the manufacture of a circular polarizing plate including a λ/4 plate having a larger Nz coefficient, it is sometimes impossible to use a highly productive manufacturing technique such as a continuous winding technique. However, the influence only involves the observation of the circular polarizer on the side of the face or the back side, which has a minimal effect compared to the case of a circular polarizer involving both sides. In the above aspect (1), the combination of the first λ/4 plate and the second birefringent layer may be a laminate formed by laminating an adhesive (intervening agent), but it is preferably A laminate formed by laminating adhesive. As described above, as a preferred embodiment of the liquid crystal display device of the present invention, the first λ/4 plate and the first birefringent layer are disposed on the back side of the liquid crystal cell, and the Nz coefficient of the first λ/4 plate is as described above. A form larger than the Νζ coefficient of the second λ/4 plate. In this form, there is a case where it is difficult to manufacture the λ/4 plate by the oblique stretching method suitable for the continuous winding technique. Therefore, from the viewpoint of suppressing the influence to a minimum, the form is preferably produced by the following method. That is, the second birefringent layer is attached to the first polarized layer by means of a continuous casting technique using an adhesive to the first polarized light 163390.doc • 26-201243449 component. The first λ/4 plate is produced by a method other than the oblique stretching method (for example, a tenter transverse uniaxial stretching method, a vertical and horizontal biaxial stretching method, or the like). Then, the first λ/4 plate is attached to the second birefringent layer on the first polarizing element using an adhesive. This attachment process can also be performed by batch processing. Furthermore, if batch processing is employed, there is a concern that productivity is lowered. However, the liquid crystal display device of the present invention has a large number of advantages such as a circular polarizing plate which can be used as a commercially available product as a circular polarizing plate including a second λ/4 plate, and can flexibly cope with design changes and the like. 'Therefore, it can fully compensate for the shortcomings of batch processing. Further, if batch processing is employed in the manufacture of a circularly polarizing plate including a λ/4 plate having a larger enthalpy coefficient (= λ/4 plate which is more difficult to manufacture by a highly productive manufacturing method), There is an advantage that the λ/4 plate can be easily fabricated by a method other than the oblique stretching method. In the above form (2), a λ/4 plate having a larger Νζ coefficient (hereinafter also referred to as a λ/4 plate of a high Νζ) and a second birefringent layer closer to the Νζ 2λ/4 plate (hereinafter also referred to as The combination of the high bismuth birefringent layer may be a laminate which is formed by laminating an adhesive (intercalating agent), but is preferably a laminate in which an adhesive is laminated. As described above, a preferred embodiment of the liquid crystal display device of the present invention includes a configuration in which a λ/4 plate of a high Νζ is disposed on the back side of the liquid crystal cell. In this form, there is a case where it is difficult to manufacture a high Nzi λ/4 plate using a tilt stretching method suitable for continuous winding technology. Therefore, from the viewpoint of suppressing the influence to a minimum, the form is preferably produced by the following method. That is, the high birefringence layer is attached to the first or second polarizing element by an adhesive using a continuous winding technique. Use the method other than the tilt extension method (for example, the tenter horizontal single sleeve extension method, the vertical and horizontal double-axis extension method, etc.) 163390.doc •27- 201243449 Create a high NzU/4 board. Then, an adhesive is used to apply a high Ν^λ/4 plate (four) to the coffee-side birefringent layer on the first or third: polarizing element. This attachment process can also be performed by batch processing. In the above aspect (7), from the viewpoint of further improving the productivity, the λ plate having a smaller NZ coefficient (hereinafter also referred to as a low Nz W plate) is preferably laminated by a lower method to a lower plate. The second birefringent layer (hereinafter also referred to as a low-side birefringent layer) is in the vicinity. That is, the low-side birefringent layer is attached to the first or second polarizing element by an adhesive using a continuous spreading technique. A low Ν^λ/4 plate was produced using the oblique extension method. Then, a low-twist 2λ/4 plate is attached to the low-side side money-emitting layer on the first or second polarizing element using a continuous winding technique. Adhesives can be used for the attachment of low Nzu/4 plates, or adhesives can be used. The combination of the first λ/4 plate and/or the second λ/4 plate and the third birefringent layer is preferably a laminate which is laminated without interposing an adhesive. Such a laminate can be produced, for example, by a method in which an adhesive is laminated simultaneously with an extrusion film by a co-extrusion method or the like, or one of the birefringent layers in the laminate is included in a polymer film, and A method of laminating or transferring another birefringent layer containing a liquid crystalline material or a non-liquid crystal material onto the polymer film by coating. In many cases, the first birefringent layer is produced by coating a liquid crystal material such as a non-liquid crystal material such as polyimine or a liquid crystal material such as a cholesteric liquid crystal, so that the latter method of coating or transferring can be used. It is preferably used for the fabrication of a laminate of a first λ/4 plate and/or a second λ/4 plate and a third birefringent layer. Hereinafter, the action of the second and third double 163390.doc -28 · 201243449 refractive layers in the liquid crystal display device of the present invention will be described. As an example, consider sequentially stacking a first one-two birefringent layer, a first λ/4 plate (first birefringent layer), a first refracting layer, a liquid crystal cell, and a second λ/4 plate ( The circularly polarized VA mode liquid crystal display device of the present invention according to the above aspect (1) of the first type of birefringent layer and the second polarizing element. In the liquid crystal display device (8), light incident from the front direction with respect to the first polarizing element is converted into linear polarized light by the first polarizing element, and

Passing through the second birefringent layer in a state of being polarized, and converting from linear polarization to circular polarization by the first λ plate and penetrating the second birefringent layer and the liquid crystal cell while maintaining the polarization state And converting from the circularly polarized light to the linear polarized light of the same polarized state as that immediately after penetrating the first polarizing element by the second λ/4 plate in a positive-female relationship with the λ/4 plate described above, and by The second polarizing element orthogonal to the first polarizing element blocks linear polarization, thereby obtaining a good black display. That is, the purpose of the second and third birefringent layers is not to switch the polarization state of light incident from the front direction. Furthermore, the above description has been made on the case where the black display is obtained by tracking the polarization state which changes every time the layers are penetrated, but it is more intuitively understood by the following description. That is, in the liquid crystal display device, in the front direction, (1) the first and second λ/4 plates included between the first and second polarizing elements are substantially orthogonal to each other, and the phase difference between them is substantially The same (λ/4) is substantially invalidated by canceling the phase difference, and (2) the phase axis and the first polarization of the second birefringent layer included between the first and second polarizing elements Since the absorption axis of the element is substantially orthogonal, it is substantially ineffective. (3) Since the third birefringent layer and the liquid crystal cell included between the first and second polarizing elements are on the front side Since the directional phase difference is substantially zero, it is substantially invalidated, and further, (4) since the first and second polarizing elements are substantially orthogonal to each other to form a so-called orthogonal polarizing element, a good orthogonal polarizing element can be obtained. Black display (can also be a full black display). On the other hand, if the liquid crystal display device (A) assumes that there is no conversion of the polarization state caused by the second and third birefringent layers in the oblique direction, it may be caused with respect to the first polarizing element for the following three reasons. The light incident from the oblique direction is not blocked by the second polarizing element, so that a complete black display cannot be obtained. Namely, the purpose of the first and second birefringent layers is to convert the polarization state of the light which is mainly incident from the oblique direction (it is also possible to convert only the polarization state of the light incident obliquely), thereby performing the viewing angle compensation. As described above, the state of the black display of the second and third types in the liquid crystal display device of the present invention

163390.doc The birefringent layer can maintain the positive direction up and down, and also has a good black display in the oblique direction. • 30· 201243449 90°) ll〇, first person / 4 boards (late phase axis orientation ^^) 20, VA The mode liquid crystal single 130, the second λ/4 plate (late phase axis orientation 45) 140 and the second polarizing element (absorption axis orientation 0.) 150 and does not include the second and third birefringent layers. The simplest circularly polarized VA mode liquid crystal display device is 1. In addition, the arrows depicted in the first and second polarizing elements 110, 15A in Fig. 2 indicate the orientation of the absorption axis, first and second. The arrows depicted in the χ/4 plates 12〇, 140 indicate the orientation of the slow axis, and the ellipsoid depicted by 0 in the VA mode liquid crystal cell 130 indicates the shape of the index ellipsoid. In black, the light incident from the front direction with respect to the first polarizing element 丨1() is converted into linear polarized light by the first polarizing element 11 ,, and converted from linear polarized light to a circle by the first λ/4 plate 120. Polarizing, and penetrating the liquid crystal cell 130 in a state of maintaining a polarization state, and by the above A λ/4 plate 120 is in the second χ/4 plate 140 in an orthogonal relationship and is again converted from circularly polarized light to a linearly polarized light of the same polarized state as immediately after penetrating the first polarizing element 11 且 and by the first The second polarizing element 150 orthogonal to the polarizing element 11 () blocks linear polarization, thereby obtaining a good black display. In other words, in the liquid crystal display device 100, in the front direction, (i) due to the first The first and second input/four plates 120 and 140 included between the second polarizing elements 110 and 150 are orthogonal to each other and have the same phase difference (λ/4), so that they are invalidated by mutually canceling the phase difference. (2) Since the liquid crystal early element 130 included between the first and second polarizing elements 110 and 150 is zero in the front direction, the phase difference is substantially invalidated, and (3) due to the first The second polarizing elements 110 and 150 are orthogonal to each other to form a so-called orthogonal polarizing element, so that a complete black display can be obtained. 163390.doc -31- 201243449 Then consider the black display in the oblique direction, because the following viewing angle obstructs the cause ( 1) ~(3) It is impossible to obtain a complete black display. (1) Since the second λ/4 plates 120 and 140 are not orthogonal to each other or have different phase differences from each other, they are not invalidated. (2) Since the phase difference of the liquid crystal cell 130 is not zero, it is not invalidated. (3) Since the first and second polarizing elements 110 and 15 are not orthogonal to each other, they do not constitute a crossed polarizing element. The above-described viewing angle obstruction causes (1) to (3) will be described in more detail with reference to Fig. 3 . As shown schematically in FIG. 3(a), in the front direction (normal to the substrate surface), the slow phase axis of the first λ/4 plate 120 and the second λ/4 plate 140 are retarded. 141 are mutually orthogonal 'relative to this, in the orientation 〇. The retardation axis 121 of the first λ/4 plate 120 and the slow phase axis 1 of the second λ/4 plate 140 are not mutually positive and therefore do not cancel each other out of phase difference and thus are not invalidated. Further, as schematically shown in FIG. 3(b), in the front direction, the slow phase axis 121 of the first λ/4 plate 120 and the retardation axis 141 of the second λ/4 plate 140 are opposite to each other' , at azimuth 45. In the middle direction, although the first and second χ/4 plates 120 and 140 are opposite to each other, the slow phase axis 121 and the slow phase axis 141 are different from each other, and thus the phase difference is not canceled each other. The phase difference is determined by the birefringence (refractive index difference) ’ thickness. The reason is that the effective birefringence is different in the front direction and the oblique direction, and also depends on the orientation. For the same reason, the phase difference of the VA mode liquid crystal cell 130 which is zero in the front direction is not zero in any oblique direction because the effective birefringence is only zero in the front direction and the phase difference is also zero. Further, as shown schematically in FIG. 3(c), in the front direction, the absorption axis u丨 of the first polarizing element 110 and the absorption axis 163390.doc •32·201243449 151 of the second polarizing element 丨5 相互 are orthogonal to each other' In contrast, the orientation is 45. In the oblique direction, the absorption axis 111 of the first polarizing element 110 and the absorption axis 151 of the second polarizing element 150 are not orthogonal to each other. As described above, the circularly polarized VA mode liquid crystal display device 100 of the smallest configuration cannot obtain a complete black display obliquely due to the above three viewing angles obstructing the causes (丨) to (3). Conversely, if the processing for such obstructive reasons can be performed, that is, optical compensation is performed, a better black display can be obtained in the oblique direction. Further, in many cases, the above-mentioned viewing angles are observed in combination to interfere with the causes (1) and (2). Therefore, it is also possible to use a method in which the viewing angle interferes with the causes (1) and (2) as a whole, rather than individually optimizing, in the case of optical compensation for the same. Further, the liquid crystal display device (A) is designed to simultaneously perform optical compensation for the above-mentioned viewing angle obstruction cause - (3) based on the design as described in detail below. Specifically, first, after the first and second λ/4 plates are made into a biaxial λ/4 plate (the first birefringent layer) satisfying the relationship of ηχ>η to ηζ, The Νζ coefficients are different from each other, and secondly, a birefringent layer (second birefringent layer) satisfying the relationship of nx < nySnz is disposed between the first λ/4 plate and the first polarizing element, and then, as needed A birefringent layer (a third birefringent layer) satisfying the relationship of nx and ny > nz is disposed between the second λ/4 plate, thereby achieving optical compensation. Here, the design policy of the birefringent layer will be described. The inventors of the present invention conducted various studies in order to easily and efficiently perform optical compensation for the above-mentioned viewing angle obstruction, and as a result, attention has been paid to factors that require optical compensation depending on the orientation. And found that, as shown in the following table, at the orientation 163390.doc -33-201243449 0°, it is not necessary to perform optical compensation of the polarizing element for the viewing angle obstruction reason (3), and it is found that only the viewing angle is in this orientation. Reasons for obstruction (1) Optical compensation of the λ/4 plate and optical compensation of the liquid crystal cell may be performed for the cause of the viewing angle obstruction (2). [Table 1] Azimuth Necessity of optical compensation (1) λ/4 plate (2) Liquid crystal cell (3) Polarizing element 0° Required Required No 45. Needs need further, the inventors have thought of: by using the Poincare Sphere (Poincare Sphere) polarization state diagram and computer simulation, the average value Nzq of the first and second λ/4 plates and the liquid crystal cell The thickness direction phase difference Rlc is optimally adjusted, and further, a third birefringent layer satisfying the relationship of nx=ny>nz is disposed between the first and second λ/4 plates as needed, and the thickness direction thereof is also The phase difference R3 is optimally adjusted, whereby the above-mentioned viewing angle obstruction causes (1) and (2) can be optically compensated simultaneously and effectively in the orientation 0°. In the present specification, the average value Nzq of the first and second λ/4 plates is selected as the above, and the thickness direction phase difference Rlc of the liquid crystal cells and the third type are selected for the purpose of optical compensation in the orientation of 0°. The process of the optimum value of the thickness direction phase difference R3 of the birefringent layer is referred to as the first step. Moreover, the inventors have thought that after the first step, a second birefringent layer satisfying the relationship of nx <ny$nz is disposed in-plane between the first λ/4 plate and the first polarizing element. The phase-increasing axis is substantially orthogonal to the absorption axis of the first polarizing element, and the Νζ coefficient Nz2 and the in-plane phase difference R2 are optimally adjusted to 163390.doc -34-201243449, which can be at azimuth 45. (4) Effectively compensate optically for the above-mentioned visual angle obstruction causes (1), (7), and (3). In the present specification, the process of selecting the optimum value of the Nz coefficient Nz2 and the in-plane phase difference R2 of the second birefringent layer for the purpose of optical compensation in the orientation 45 之后 after the first step as described above is referred to as The second step. Since the in-plane phase axis of the second birefringent layer added in the second step is disposed substantially orthogonal to the absorption axis of the adjacent first polarizing element,

Therefore, the orientation has not changed substantially. The optical characteristics in the direction (which may not change at all) gp, after the second step, the optimum state obtained by the first step is still preserved as a feature of the optical compensation process of the liquid crystal display device of the present invention. Thus, the first step and the second step can be studied completely independently, thereby making the design of the birefringent layer easy. The details of the optical compensation principle of the first step of the above first step are explained by using the diagram of the Poincare sphere. In the field of crystallography and the like, it is known as a method for tracking the polarization state which changes by the birefringent layer (see, for example, Non-Patent Document 3). In the magical Calais ball, the upper hemisphere indicates right-handed polarized light, and the lower hemisphere indicates that the left-handed polarized light is not linearly polarized. The upper and lower poles indicate right-circular polarized light and left-circular polarized light. The two polarization states in a symmetrical relationship with respect to the center of the sphere are formed as the effect of the birefringent layer on the orthogonal polarized Poincare sphere due to the equal absolute values of the ellipticity angles and opposite polarities: The point of the polarization state before the layer is converted to the late phase on the reading Calais 163390.doc -35· 201243449 The mold ^ more accurately, in other words, the two natural vibrations of the birefringent layer 卞Position of the point on the Poincare sphere) ^ Rotate counterclockwise to move the point determined by the angle of (2π) χ (phase difference) / (wave early position rad) (centered on the phase axis) In the clockwise direction, the rotation center and the rotation angle are also determined by the slow phase axis (or the phase advance axis) and the phase difference at the observation angle. Although the detailed description is omitted, the shot is as follows. The vibration direction and wave vector of the biaxial 'natural vibration mode are obtained by solving the Fresnel wave normal equation. The slow phase axis from the oblique observation depends on the observation angle and the Nz coefficient, and observes from the oblique direction. Capture the phase The difference depends on the observation angle, the Nz coefficient, and the in-plane phase difference R (or the thickness direction phase difference Rth). (Compensation principle of the first step) Second, first consider the circularly polarized VA mode liquid crystal display of Figure 2 from the front direction. 00 o'clock polarized state.; ^ Under this condition ' ^ use Poincaré ball iSl-S2 plane and the illustration from the backlight (not shown in Figure 2, is located below the first "component") The polarization state when the polarizing elements 11 150, 150 and the birefringent layers 12 〇, 14 〇 and the liquid crystal cell m are penetrated, as shown in Fig. 4. Further, the points indicating the respective polarization states are actually located in Poincaré. On the spherical surface, the projections are shown in the S1-S2 plane. In addition, the point of the non-polarized state is indicated by x, and the point of the late (in) phase axis of the birefringent layer is indicated by x. The polarizing state after penetrating the first-polarizing element 11〇 is at the point P0 on the top of the Pangga-up, and the second polarizing element represented by the point E is 133390.doc-36 - 201243449. The extinction position of 150 (absorption axis orientation) is consistent. Then, by penetrating the first person / 4 board 120 The polarization state at the point p〇 is converted to a point ρ 1 by the rotation of the slow phase axis of the first λ/4 plate 12 表示 indicated by the point Qi on the magical ball. At this time, the suspected direction is observed from the point Q 1 toward the origin point (the center point of the Poincare sphere) as a counterclockwise direction. Then, the VA mode liquid crystal unit 130 is penetrated, but the VA mode liquid crystal unit 0 U is on the front side. The direction phase difference is zero, so there is no change in the polarization state. Finally, by penetrating the second λ plate mo, the rotation is rotated at a specific angle centering on the slow phase axis of the second λ/4 plate 14 表示 indicated by the point Q2. The conversion is such that it reaches the point Ρ 2 ' and the point Ρ 2 coincides with the extinction position ε of the second polarizing element 15 。. Thus, the liquid crystal display device 1 of Fig. 2 can block the light from the backlight when viewed from the front direction to obtain a good black display. Further, the absorption axis orientation 第二 of the second polarizing element 15〇 is considered. Tilt from the normal line by 60. The direction (hereinafter also referred to as pole 6 〇.) The polarization state of the VA mode liquid crystal display device 100 of Fig. 2 is observed. Under this condition, if the S1-S2 plane of the Poincare sphere is used, the polarization state of the light emitted from the backlight when penetrating each of the polarizing elements 110, 150, the respective birefringent layers 120, 14 and the liquid crystal cell 130 is shown. , as shown in Figure 5. First, the polarization state immediately after the first polarizing element 丨1〇 is located at the point P0 on the Poincare sphere, and the second polarizing element 丨5〇 which is the polarization state absorbable by the second polarizing element 15 表示The extinction position (absorption axis orientation) is the same. Then, by penetrating the first person/4 plate 12(), the polarization state at the point p〇 is the λ390 of the first λ/4 plate 12〇 indicated by the point Q1 on the Poincare sphere. .doc -37- 201243449 The heart is rotated by a specific angle, so as to reach the fip. The direction of rotation is observed counterclockwise from the point Q1 toward the origin. Then, by penetrating the VA mode liquid crystal cell 13A, * is rotated by a specific angle centered on the slow phase axis of the liquid crystal cell 13 () indicated by the point L on the Poincare sphere, thereby reaching the point β2β The direction of rotation is from ^ to the origin. The observation is counterclockwise. Finally, # is penetrated by the second person, 4 plates, and is rotated by a specific angle centered on the slow phase axis of the second λ/4 plate 14〇 indicated by the point Q2, thereby reaching the point immediately, and the point ρ3 And the matte level of the second polarizing element 150. For example, <, the liquid crystal display device 100 of Fig. 2 is self-aligned. Extreme 60. When observing, the light from the backlight cannot be blocked. Furthermore, in FIGS. 4 and 5, the position of the points Ρ1 to Ρ3 depends on the Νζ coefficient Nzql of the first plate 120 and the Νζ coefficient of the second λ/4 plate 14〇. ^^^ and the thickness direction phase difference Ric of the liquid crystal 130, which are illustrated in FIG. 4 and FIG.

The form of Nzql-Nzq2=2.0 and Rlc=32〇 nm2 is taken as an example. In order to easily understand the transition of the polarization state, the position of each point is roughly indicated, and sometimes it is not accurate in some cases. Further, in order to clearly show the figure, there is no arrow indicating the trajectory for the conversion of the point p1. Further, the Rlc of the VA mode liquid crystal cell is typically about 320 nm, but can usually be adjusted within the range of 270 to 400 nm. For example, Nzql and Nzq2, where R1CS is greater than m, and R1CS is greater than m, and λ/4 plates 120 and 140 are usually adjusted in the range of 1_〇 to 2.9. For example, in the case of using a VA mode liquid crystal cell in which Rlc is set to about 4 〇〇 nm and in the form in which the third birefringent layer is not provided, it is preferable to adjust the average value of the Nz coefficients to 163390.doc - 38- 201243449 2.9 of 2 sheets of 1/4. Then, it is considered to sequentially laminate a first polarizing element (absorption axis orientation 90) 210, a first λ/4 plate (latial phase axis orientation 135.) 220, a third birefringent layer 235, as shown in FIG. VA mode liquid crystal cell 230, second λ/4 plate (latial phase axis orientation 45) 240 and second polarizing element (absorption axis orientation ).) 25 圆 circularly polarized VA mode liquid crystal including a third birefringent layer Display device 200. Furthermore, the arrows depicted in the "Dipole 1 and 2" polarizing elements 210, 250 in Fig. 6 indicate the orientation of the absorption axis, and the arrows depicted in the first and second persons/4 plates 220, 240 indicate The orientation of the slow phase axis, the ellipsoid system depicted in the VA mode liquid crystal cell 230 and the third birefringent layer 235 represents the shape of the index ellipsoid. First, the polarization state when the circularly polarized VA mode liquid crystal display device 200 of Fig. 6 is viewed from the front direction is considered. Under this condition, if the S1-S2 plane of the Poincare sphere is used, the light emitted from the backlight (not shown in FIG. 6 below the first polarizing element 210) penetrates each of the polarizing elements 21〇. The polarization state of each of the birefringent layers 22A, 240, 235 and the liquid crystal cell 230 is shown in FIG. First, the polarized state immediately after penetrating the first polarizing element 210 is located at a point Ρ0 on the Poincare sphere, and the second polarizing element 25, which is indicated by the point Ε, is absorbing the polarized state, that is, the second polarizing element 250. The extinction position (absorption axis orientation) is the same. Then, by penetrating the first λ/4 plate 220, the polarization state at the point 受到 is specified centered on the slow phase axis of the first λ/4 plate 22 表示 indicated by the point Q1 on the Poincare sphere. The rotation of the angle is converted to reach the point ρι. At this time, the direction of rotation is observed counterclockwise from the point Q1 toward the origin. 163390.doc •39- 201243449 Then, the third birefringent layer 235 and the VA mode liquid crystal cell 230 are penetrated, but since the third birefringent layer 235 and the VA mode liquid crystal cell 230 have a phase difference of zero in the front direction, There is no change in the polarization state. Finally, by penetrating the second λ-plate 24〇, the rotation is converted by a specific angle centering on the slow phase axis of the second λ/4 plate 240 indicated by the point Q2, thereby reaching the point Ρ2, and the point Ρ2 It is the same as the extinction position of the second polarizing element 250. Thus, the liquid crystal display device 200 of Fig. 6 can block the light from the backlight when viewed from the front direction, as in the liquid crystal display device 100 of Fig. 2, thereby obtaining a good black display. Further, the absorption axis orientation 第二 of the second polarizing element 210 is considered. The polarized state of the circularly polarized VA mode liquid crystal display device 200 of Fig. 6 was observed from the direction of inclination of 60°. Under this condition, if the light emitted from the backlight is used to penetrate the polarizing elements 21, 250, the respective birefringent layers 220, 240, 23 5 and the liquid crystal cells 23 0 using the S1_S2 plane of the Poincare sphere. The polarized state is shown in Figure 8.1. The first polarizing element is a polarization state in which the polarizing state immediately after penetrating the first polarizing element 210 is located at the point P0 on the Poincare sphere, and the second polarizing element 25 is represented by the point E, that is, the second polarizing element 2 5消 消 extinction position (absorption axis orientation) _ Zhi. Then, by penetrating the first λ/4 plate 22, the polarization state at the point P 受到 is centered on the slow phase axis of the first λ/4 plate 22 表示 indicated by the point Q1 on the Poincare sphere. The rotation of a specific angle is converted to reach the point ρι. At this time, the direction of rotation is observed counterclockwise from the point Qi toward the origin. Then, by penetrating the third birefringent layer 235, the rotation is converted by a specific angle of 163390.doc 201243449 centered on the slow phase axis of the third birefringent layer 235 indicated by the point R3 on the Poincare sphere. And thus reach point P2. The direction of rotation at this time is observed counterclockwise from the point R3 toward the origin Ο. Then, by penetrating the VA mode liquid crystal cell 230, the rotation is converted by a specific angle centering on the slow phase axis of the liquid crystal cell 230 indicated by the point L on the Poincare sphere, thereby reaching the point P3. At this time, the direction of rotation is observed from the point L toward the origin Ο in the counterclockwise direction. Finally, by penetrating the second λ/4 plate 240, the rotation is converted by a specific angle centering on the slow phase axis of the second λ/4 plate 240 indicated by the point Q2, thereby reaching the point Ρ4, and the point The extinction position of the second polarizing element 250 is the same as that of the second polarizing element 250. Thus, the liquid crystal display device 200 of Fig. 6 can block light from the backlight as viewed from the front direction when viewed from the oblique direction of 0° and 60°. Furthermore, in FIGS. 7 and 8-1, the position of the point Ρ1-Ρ4 depends on the Νζ coefficient Nzql of the first λ/4 plate 220, the Νζ coefficient Nzq2 of the second λ/4 plate 240, and the third birefringence. The thickness direction phase difference R3 of the layer 235 and the thickness direction phase difference Rlc of the liquid crystal cell 230 are shown in FIGS. 7 and 8-1 in the form of Nzql=Nzq2=2.0, R3=-61 nm, and Rlc=3 20 nm. As an example. In order to easily understand the transition of the polarization state, the position of each point is roughly indicated, and sometimes it is not accurate in principle. Further, in order to clearly show the map, arrows indicating the trajectory are not shown for the transition of the points P1 to P4. Moreover, the inventors have studied and found out that the optimum phase difference value of the third birefringent layer 235 exists in the corresponding coefficient zNzq1 of the first λ/4 plate 220 and the Νζ coefficient Nzq2 of the second λ/4 plate 240. R3. Here, the Νζ coefficient Nzq1 of the first λ/4 plate 220 and the Νζ coefficient Nzq2 of the second λ/4 plate 240 and the third birefringent layer 23 5 163390.doc -41 · 201243449 will be investigated by computer simulation. The results obtained by the relationship between the optimum values of the thickness direction retardation R3 are shown in Table 2 and Fig. 9. In the illustration of the Poincare sphere used in Fig. 8-1, it is divided into Pl->P2 conversion using the thickness direction phase difference R3 of the third birefringent layer 235, and the thickness of the liquid crystal cell 230 using the VA mode. The directional phase difference RlciP1 - p2 is converted and the polarization state transition of the plotted points P1 - P3 is performed. However, the two conversions only say that the center of rotation is the same and the direction of rotation is opposite, and the direction of rotation is determined by the sign of the phase difference in the direction of the yield. The angle of rotation is determined by the absolute value of the phase difference in the thickness direction. Therefore, even if the above two kinds of conversions are intended to be "the third birefringent layer 235 + VA mode liquid crystal cell 230", the direct PI-P3 conversion using the "total thickness direction phase difference R3 + Rlc" is also the same. In other words, as long as R3 + Rlc is the same, the optical characteristics of the liquid crystal display device do not differ depending on the thickness direction phase difference Ric of the VA mode liquid crystal cell 230. Therefore, Table 2 shows the results of calculating the optimum value of R3+R1C by computer simulation. Moreover, for the sake of simplicity, although the Nz coefficient Nzql of the first λ/4 plate 220 is the same as the Νζ coefficient Nzq2 of the second λ/4 plate 240 (Nzql=Nzq2=Nzq), the computer simulation is performed. It has been found that, as explained below, even if the Nz coefficient Nzql of the first/fourth board 220 and the Nz coefficient Nzq2 of the second λ/4 board 240 are different from each other, it can be considered as Nzql and Nzq2. Each of them is equal to the average value Nzq', and the optimum phase difference value R3 of the third birefringent layer 235 is calculated from the Nzq, so that the results of Table 2 and FIG. 8 can be directly referred to. As can be seen from Table 2 and Fig. 9, the following equation (A) is sufficiently approximated if the relationship between the average value Nzq and the optimum Rlc+R3 is in the range of 1.0 SNZqS2.9. The solid line shown in Fig. 9 represents the following formula (A).

Rlc+R3 = 169 nmxNzq-81 nm (A) 163390.doc -42· 201243449 As the thickness direction phase of the third birefringent layer 235 from the viewpoint of realizing a liquid crystal display having a high contrast in a wide viewing angle range R3+Rlc which is the sum of the thickness direction phase difference Rlc of the difference R3 and the VA mode liquid crystal cell 230 in the black display (when no voltage is applied to the liquid crystal layer) is optimally the optimum values shown in Table 2 and FIG. However, as long as the range of contrast under oblique viewing angle is not greatly reduced, it may be slightly deviated from the optimum value. From the viewpoint of sufficiently exerting the effect of the liquid crystal display device of the present invention, it is preferably in the range of an optimum value of 50 nm. [Table 2]

Nzq Rlc+R3(nm) 1.00 88 1.10 105 1.20 122 1.30 140 1.40 157 1.50 174 1.60 191 1.70 208 2.00 259 2.30 309 2.40 325 2.50 342 2.90 406 此处 Here, the reasons for the following cases are explained: even in the first λ When the Νζ coefficient Nzql of the /4 plate 220 and the Νζ coefficient Nzq2 of the second λ/4 plate 240 are different from each other, the third type calculated by using each of the assumptions Nzql and Nzq2 is equal to the average value Nzq. The optimal phase difference of the birefringent layer 235 is 163390.doc -43- 201243449 R3 'to block the self-alignment. Very extreme. Leakage when viewed obliquely, resulting in excellent viewing angle characteristics. Fig. 8-1 shows a form in which Nzqi = Nzq2 = 2.0, R3 = -61 nm, and Rlc = 320 nm as described above. 8-2 is a diagram showing the form of Nzql=3.0, Nzq2-1.0, R3=-61 nm, and Rlc=320 nm. FIG. 8_3 shows that Nzql=2.5, Nzq2=1.5, R3=-61 nm, Rlc. =320 nm, Figure 8-4 shows the form of Nzql = l.〇, Nzq2=3.0, R3=-61 nm, and Rlc=320 nm. Figure 8-5 shows Nzql = 1.5 and Nzq2=2.5 The form of R3=-61 nm and Rlc=320 nm, and the average value Nzq of Nzql and Nzq2 thereof is 2.0 as in the case of FIG. 8-1. As is clear from the observation, in either form, the point P4 is coincident with the extinction position E of the second polarizing element 250 in the self-aligning direction of the liquid crystal display device. Extreme 60. In the case of oblique observation, the light from the backlight can be blocked as in the case of viewing from the front. As shown in Fig. 8-6, the slow phase axis Q1 of the first χ/4 plate 220 is based on the case where Nzql is 2.0. If Nzql is less than 2.0, it is closer to the S2 axis side. If it is greater than 2_0, it is closer to the axis. Further, the retardation axis Q2 of the second person/four plate 240 is based on the case where Nzq2 is 2_0, and if Nzq2 is larger than 2.0, it is closer to the S1 axis side. If it is less than 2.0, it is closer to the S2 axis side. The design of Nzql=Nzq2=Nzq=2.0 is used as a reference. When Nzql is set to a small extent with ANzq, Nzq2 is set to a large extent with ANzq, thereby converting the rotation center of P0-P1 conversion and P3-P4. The center of rotation is appropriately displaced in the same direction, thereby keeping ZP1 POP3 substantially the same. As a result, as in the case of Nzql=NZq2=Nzq=2.0, the point P4 can be made coincident with the extinction position e of the polarizing element 163390.doc-44-201243449250. Contrary to this case, when Nzql is set to a large extent with the degree of ANzq with the design of Nzq1=Nzq2=Nzq=2.0, Nzq2 is set to a small extent with ANzq, whereby PO_>P1 can be converted. The center of rotation and the center of rotation of the P3 -> P4 transformation are appropriately displaced in the same direction, and as a result, Similarly to the case where Nzq1=Nzq2=Nzq=2.0, the point P4 can be made coincident with the extinction position E of the polarizing element 250. By the above method, even the Nz coefficient Nzql of the first λ/4 plate 220 and the second λ/4 plate When the Nz coefficients Nzq2 of 240 are different from each other, it is also possible to block by using the optimum phase difference R3' of the third birefringent layer 235 calculated by assuming that each of Nzql and Nzq2 is equal to the average value Nzq. The self-direction 〇°, the pole 60. The light leakage when viewed obliquely' thus obtains excellent viewing angle characteristics. Furthermore, if the Nz coefficient Nzql and the Nz coefficient Nzq2 are separately processed, the design of the phase difference condition becomes extremely Therefore, the meaning of the optimum phase difference value R3 can be calculated using the average value Nzq. (Compensation principle of the second step) First, the absorption axis orientation of the first polarizing element 210 is 90° and the second polarizing element 250 is considered. Absorbing axis orientation 〇° halved position (azimuth 45°) in the direction of self-tilting 60. The liquid crystal display device 200 of Fig. 6 which completed the first step is observed. As described above, 'in the first step' The display device 2 is based on the first λ/4 plate 220 The Nz coefficient Nzq1 and the Nz coefficient Nzq2 of the second λ/4 plate 240 select the optimum value of the thickness direction phase difference Rlc of the liquid crystal cell 230 and the thickness direction phase difference R3 of the third birefringent layer 235, thereby performing the orientation 0. In this condition, if the S1_S2 plane of the Poincare sphere is used, the light emitted from the backlight penetrates each of the polarizing elements 210, 163390.doc-45-201243449 250, and each birefringent layer 220. The polarization state of 240, 235, and liquid crystal cell 230 is as shown in FIG. First, the polarization state immediately after the first polarizing element 21 is penetrated on the Poincare sphere at the point P0', and the polarization state of the second polarizing element 250, which is represented by the point E, is the extinction state of the second polarizing element 250. The position (absorption axis orientation) is inconsistent. At azimuth 45. In the oblique direction, since the first and second polarizing elements 21, 250 are not orthogonal to each other, it is suggested that optical compensation is required. Then, by penetrating the first λ/4 plate 220, the polarization state at the point P 受到 is subjected to a specific angle centering on the slow phase axis of the first λ/4 plate 220 indicated by the point Q1 on the Poincare sphere. The rotation is converted to reach the point ρι. At this time, the direction of rotation is observed counterclockwise from the point Q1 toward the origin. Then, by penetrating the third birefringent layer 235, the rotation is converted by a specific angle centering on the slow phase axis of the third birefringent layer 235 indicated by the point R3 on the Poincare sphere. Point p2. Direction of rotation

. Then, by penetrating VA

The liquid crystal display device 200 of the step is at an orientation 45. 163390.doc is observed from the point R3 toward the origin 为 as a counterclockwise mode liquid crystal cell 230, and by the light of the Poincare sphere. That is, the light is not compensated for -46- 201243449. Furthermore, in FIG. 10, the positions of the points P1 to P4 depend on the first coefficient λ/4 plate 22 Νζ coefficient Nzq1, the second λ/4 plate 240 ΝΖ coefficient Nzq2, and the thickness of the third birefringent layer 235. The direction phase difference R3 and the thickness direction phase difference Rlc of the liquid crystal cell 23〇 are shown in FIG. 10 as Nzql=Nzq=2.0, R3=-61 nm,

The form of Rlc=320 nm is taken as an example. In order to easily understand the transition of the polarization state, the position of each point is roughly indicated, and sometimes it is not accurate. Further, in order to clearly show the map, arrows indicating the trajectory are not shown for the transition of the points P1 to P4. Then, it is considered that a first polarizing element (absorption axis orientation 90) 310 and a second birefringence layer (phase axis azimuth 0) 315 are sequentially stacked as shown in FIG.

The first λ/4 plate (late phase axis orientation 135.) 32 〇, the third birefringent layer 335, the VA mode liquid crystal cell 330, the second λ/4 plate (late phase axis orientation 45) 34 〇 and the second A circularly polarized VA mode liquid crystal display device 3 comprising a second birefringent layer of a polarizing element (absorption axis orientation 〇). The second birefringent layer is intended to be oriented 45. The optical compensation in the middle is added to the figure. Furthermore, in FIG. 11, the arrows depicted in the first and second polarizing elements 310, 350 indicate the orientation of the absorption axis, and the arrows depicted in the first and second persons/4 plates 320, 340 indicate The orientation of the slow phase axis, the arrow depicted in the second birefringent layer 315 indicates the orientation of the phase axis, and the ellipsoids interposed in the VA mode liquid crystal cell and the third birefringent layer 335 indicate the refraction. Rate the shape of the ellipsoid. First, consider the polarization state of the circular polarization mode liquid crystal display and the device 300 when the image is viewed from the front. If the plane of the magical Calais ball is used, 163390.doc -47·201243449, the light emitted from the backlight (not shown in the figure below, which is located below the first-polarizing element 31〇) is used to penetrate the polarizing elements. The polarization state of 31 〇, 35 〇, each of the birefringent layers 320, 340, 335, and 31 5 and the liquid crystal cell 33 is as shown in FIG. First, the polarized state immediately after penetrating the first polarizing element 310 is located at the point P0 on the Poincare sphere, and the polarized state absorbable by the second polarizing element 35 indicated by the point E is the extinction of the second polarizing element 350. The position (absorption axis orientation) is the same. Then, 'the second birefringent layer 315 is penetrated, but the polarized state at the point is subjected to a specific angle centering on the phase axis of the second birefringent layer 3 15 indicated by the point R2 on the Poincare sphere. With the rotation conversion, the polarization state does not change from the point P0. Then, by the penetrating state of the first λ/4 plate 32 〇 ' at the point Ρ 0 to be centered on the slow phase axis of the first λ/4 plate 320 indicated by the point Q 1 on the magical ball, The rotation of the angle is converted to reach point Ρ1. At this time, the direction of rotation is observed counterclockwise from the point Q1 toward the origin. Then, the third birefringent layer 335 and the VA mode liquid crystal cell 330' are penetrated. However, since the third birefringent layer 335 and the VA mode liquid crystal cell 33 have a phase difference of zero in the front direction, the polarization state does not change. Finally, by penetrating the second λ/4 plate 340, the rotation of the specific angle is centered on the slow phase axis of the second λ/4 plate 340 indicated by the point Q2, thereby reaching the point Ρ2. This point Ρ2 is equal to the extinction position ε of the second polarizing element 350. Thus, when viewed from the front direction, the liquid crystal display device 300 of FIG. 9 can block the light from the backlight as in the liquid crystal display device 100 of FIG. 2, thereby obtaining a good black display>|ν ° 163390.doc - 48- 201243449 Then consider the orientation 45. The middle is tilted 60. The direction of polarization of the circularly polarized VA mode liquid crystal display device of Fig. 11 is observed in the direction of Fig. 11. Under this condition, if the light emitted from the backlight is used to penetrate the polarizing elements 310, 350, the respective birefringent layers 320, 340, 335, 315 and the liquid crystal unit 330 by using the S1-S2 plane of the Magic Calais ball. The polarized state is as shown in FIG. First, the polarized state immediately after penetrating the first polarizing element 310 is located at the point P0 on the Poincare sphere, and the second polarizing element 35, which is indicated by the point £, can absorb the polarized state, that is, the second polarizing element. The extinction position of the 350 (absorption axis orientation) is inconsistent. Then, by penetrating the second birefringent layer 315, a rotation of a specific angle is sensed centering on the phase axis of the second birefringent layer 315 indicated by the point R2 on the Poincare sphere, thereby reaching To point p丨. At this time, the direction of rotation is observed from the point R2 toward the origin 为 in the clockwise direction. Furthermore, although it exists in the southern hemisphere of the Poincaré ball (S3<0), in order to facilitate the observation, it is shown in Fig. 13 in the same manner as other points (the points existing in the northern hemisphere or the equator). Show. Then, by penetrating the first λ/4 plate 32 〇, the polarization state at the point is specifically centered on the slow phase axis of the first λ/4 plate 320 indicated by the point Q1 on the Poincare sphere. The rotation of the angle is converted to reach point Ρ2. At this time, the direction of rotation is observed from the point Q1 toward the origin 为 in the counterclockwise direction. Then, by penetrating the third birefringent layer 335, the rotation is converted by a specific angle centering on the slow phase axis of the third birefringent layer 335 indicated by the point R3 on the Poincare sphere, thereby reaching Point p3. The direction of rotation at this time is observed counterclockwise from the point R3 toward the origin Ο. Then, by penetrating the liquid crystal cell 330, the rotation is converted by a specific angle from the point on the Poincare sphere [represented by the liquid crystal single 163390.doc -49-201243449 Arrived to point P4. At this time, the direction of rotation is from the point [observed as the counterclockwise direction toward the origin point 。. Finally, by penetrating the second person/4 plate 34A, the rotation of the specific angle is reached centering on the slow phase axis of the first λ/4 plate 340 indicated by the point q2 to reach the point Ρ5. That point! >5 and the extinction position of the second polarizing element 35〇. Thus, the liquid crystal display device 3 of the figure is from the orientation 45. , pole 60. When viewed obliquely, it also blocks light from the backlight as it is viewed from the front. Finally consider the orientation 0. The middle is tilted 6 inches. In the direction of the circular VA mode liquid crystal display device of Fig. u, the state of polarization is observed. Under this condition, if the light emitted from the backlight is used to penetrate the polarizing elements 310, 350, the respective birefringent layers 32, 34, 335, 315 and the liquid crystal unit 330 by using the S1_S2 plane of the Magic Calais ball. The polarized state is as shown in FIG. - firstly 'the polarization state immediately after the penetration of the first-polarizing element 31〇 is at the point P0 on the magical ball, and the second polarizing element 35, which is the second polarizing element 35, which is absorbed by the second polarizing element 35, is the second polarizing element 35. The extinction position (absorption axis orientation) of the crucible is uniform, and then penetrates the first birefringent layer 315, but the polarized state at the point p〇 is even the second birefringent layer represented by the ruler 2 on the Poincare sphere. The phase advance axis of 315 is rotated at a specific angle from the center, and the polarized state does not change from point (9). Then, by penetrating the 1/4th plate 32, the polarization state at the point P0 is subjected to a specific angle centering on the slow phase axis of the first λ/4 plate 320 indicated by the point Q1 on the Poincare sphere. The rotation is converted to reach point P1. At this time, the direction of rotation is observed in the counterclockwise direction from the point Q1 toward the origin. 163390.doc -50- 201243449 then 'by a third angle centered on the retardation axis of the third birefringent layer 335 represented by the point R3 on the Poincare sphere by penetrating the third birefringent layer 335 Rotate the conversion to reach the point? 2. The direction of rotation at this time is observed counterclockwise from the point R3 toward the origin 〇. Then, by penetrating the va mode liquid crystal cell 330, the rotation is converted by a specific angle centering on the slow phase axis of the liquid crystal cell 330 indicated by the point L on the magical ball, thereby reaching the point P3. At this time, the direction of rotation is observed from the point L toward the origin 〇 in the counterclockwise direction. Finally, by penetrating the λ/4 plate 34, the towel is rotated by a specific angle around the slow phase axis of the second λ/4 plate 340 indicated by the point Q2, thereby reaching the point Ρ4. This point Ρ4 is equal to the extinction position of the second polarizing element 35〇. In this way, the liquid crystal display device 3 of the figure is even if it is self-aligned. , pole 60. Observed obliquely, as in the case of viewing from the front, the light from the backlight can be blocked to obtain a good black display. Thus, the liquid crystal display device 3 of Fig. 11 which has completed the second step is in the front direction and the orientation 0. Oblique and azimuth 45. In the oblique direction, the light from the backlight can be blocked to obtain a good black display. Furthermore, in FIGS. 12, 13, and 14, the positions of the points Ρ1 to Ρ5 depend on the Νζ coefficient Nzql of the first λ/4 plate 320, the Νζ coefficient Nzq2 of the second λ/4 plate 34〇, and the third type. The thickness direction phase difference r3 of the birefringent layer 335, the thickness direction phase difference ric of the liquid crystal cell 330, and the second coefficient Bz of the second birefringent layer SB and the in-plane phase difference R2 are shown in FIG. 12, FIG. The form of Nzql=NZq2=2.0, R3=-61 nm, R1C=320 nm, Nz2=-〇.3〇, and R2=l 18 nm is shown as an example. In order to easily understand the transition of the polarization state, the position of each point is roughly indicated. 'Strictly speaking, it is sometimes inaccurate. 163390.doc -51- 201243449 In addition, for the sake of clarity, the arrows indicating the trajectories are not shown for the transition of the points P1 - P5. Moreover, the inventors have studied and found that the optimum Nz coefficient Nz2 of the second birefringent layer 315 exists corresponding to the Νζ coefficient Nzq1 of the first λ/4 plate 320 and the Νζ coefficient Nzq2 of the second λ/4 plate 340. And the phase difference R2. Here, the Νζ coefficient Nzql of the first λ/4 plate 320, the Νζ coefficient Nzq2 of the second λ plate 34〇, and the Νζ coefficient Nz2 of the second birefringent layer 315 and the in-plane phase difference are investigated by computer simulation. The results obtained by the relationship of the optimum values of R2 are shown in Table 3, Figure 15, and Figure 16. Moreover, for the sake of simplicity, the computer simulation is performed by making the Νζ coefficient Nzq1 of the first λ/4 plate 320 the same as the Νζ coefficient Nzq2 of the second λ/4 plate 340 (Nzql=Nzq2=Nzq), and the present invention It is found that even when the first coefficient λ/4 plate 320 has a Νζ coefficient Nzq1 and the second λ/4 plate 340 has a different coefficient Nzq2, it can be considered by considering each of Nzql and Nzq2 and its average value Nzq. Equally, the optimum value of the second coefficient Bz of the second birefringent layer 315 and the in-plane phase difference R2 is calculated based on the Nzq, so that the results of Table 3, FIG. 15 and FIG. 16 can be directly referred to. Since the reason is the same as that described using Figs. 7-6 and the like, the description thereof will be omitted. As is clear from Table 3, FIG. 15 and FIG. 16, the relationship between the average value Nzq and the optimum Nz2 and R2 is usually not simple, but if it is in the range of 1.0 SNzqS2.9, the following formulas (B) and (C) ) fully approximate it. The solid lines shown in Figs. 15 and 16 are different.

Nz2=-0.63 xNzq2+0.56xNzq+0.40 (B) R2=43 nm><Nzq2-226 nm><Nzq+370 nm (C) A liquid crystal display having a higher contrast ratio from a wider viewing angle range View 163390.doc -52- 201243449 Point departure 'Nz2 and R2 of the above second birefringent layer 315 are optimally the best values shown in Table 3, Figure 15 and Figure 16, but as long as they are not greatly reduced The range of contrast in the oblique viewing angle may also deviate slightly from the optimum value. From the viewpoint of sufficiently exerting the effects of the liquid crystal display device of the present invention,

Nz2 is preferably in the range of the best value of 〇8〇. R2 is preferably in the range of the optimum value ± 5 。. Furthermore, if the Nz coefficient NzqmNz coefficient Nzq2 is independently processed ', the design of the phase difference condition becomes extremely complicated. Therefore, the optimum Nz2 and R2 of the second birefringent layer 315 can be calculated using the 0 average value Nzq to be extremely significant. Further, according to Table 3 and Figure I5', in the range of Nzq < 1.40, the optimum value of Nz2 is 0 < Νζ 2 < The birefringent layer exhibiting the Nz coefficient in the range satisfies the biaxial retardation film of the relationship of nx > nz > ny, and thus is not suitable for the first birefringent layer, and is more difficult to manufacture than the second birefringent layer. High cost film. Furthermore, it is better to satisfy l, 40$Nzq in terms of solving this point. The present inventors have studied the method of realizing a liquid crystal display having a relatively high contrast ratio in a wider range of viewing angles at a lower cost and in a range of Nzq <14. As a result, it was found that in the range of Nzq <l.40, if the second birefringent layer of Nz2=〇 and R2=138 nm is used, the best nz2 satisfying Table 3, 'Fig. 15 and FIG. 16 is satisfied. The birefringent layer of R2 can fully exert the same effect. For example, in each of NZq=i ·〇〇, 1. j 〇, 1 2〇, 1.30, if the optimal R2 is calculated by fixing Nz2=〇, the optimal R2 is 138ηπ regardless of the value of Nzq. From the viewpoint of sufficiently exerting the effect of the liquid crystal display device of the present invention, it is preferable to satisfy 〇8〇$νζ2^) (optimum value -0.80 or more and 〇(=optimal value) or less), and Meet 88 163390.doc -53- 201243449 nm$R2$l 88 nm (optimal value 13 8 nm ± 50 nm range). [table 3]

Nzq Nz2 R2(nm) 1.00 0.35 186 1.10 0.25 169 1.20 0.15 154 1.30 0.10 148 1.40 -0.05 134 1.50 -0.15 127 1.60 -0.30 118 1.70 -0.45 111 2.00 -1.00 94 2.30 -1.65 81 2.40 -1.90 78 2.50 -2.15 75 2.90 -3.20 66 The present inventors have also studied the form of the above (2), that is, the configuration in which the second birefringent layer is disposed on both sides of the liquid crystal cell, and found that the first and second λ are corresponding. The average value Nzq of the Nz coefficients of the /4 plate has the optimum Nz coefficient Nz2 and the phase difference R2 of the first and second second birefringent layers. Here, the Nz coefficient Nzql of the first λ/4 plate, the Nz coefficient Nzq2 of the second λ plate, and the Nz coefficient Nz2 of the first and second second birefringent layers and the in-plane are investigated by computer simulation. The results obtained by the relationship between the optimum values of the phase differences R2 are shown in Table 4, Figure 17, and Figure 18. Moreover, for the sake of simplicity, the Nz coefficient Nzql of the first λ/4 plate is the same as the Nz coefficient Nzq2 of the second λ/4 plate (Nzql=Nzq2=Nzq), and the computer simulation is performed, and the inventor is not invented. 163390.doc •54· 201243449

,, even if the first coefficient λ/4 plate N coefficient Nzql and the second λ/4 plate Νζ coefficient Nzq2 are different from each other, it can be considered that each of Nzql and Nzq2 is equal to its average value Nzq, Based on the Nzq, the optimum values of the Nz coefficient Nz2 and the in-plane phase difference R2 of the first and second second birefringent layers are calculated, and the results of Table 4, FIG. 17, and FIG. 18 can be directly referred to. Since the reason is the same as that described using Figs. 7-6 and the like, the description thereof will be omitted. As is clear from Table 4, FIG. 17 and FIG. 18, although the relationship between the average value Nzq and the optimum Nz2 and R2 is usually not simple, if it is the range of 丨.OSNzqUJ, the following formulas (D) and (E) Fully similar to it. The solid lines shown in Figs. 17 and 18 are different.

Nz2=-0.87xNzq2+2.15xNzq R2=25 nmxNzq2-159 nm><Nzq+311 nm (E) From the viewpoint of achieving a higher contrast liquid crystal display in a wider viewing angle range, the first and second The Nz2&R2 of each of the second birefringent layers is optimally the optimum values shown in Table 4, FIG. 17 and FIG. 18, but as long as the range of contrast in the oblique viewing angle is not greatly reduced, Can (4) deviate from the optimal value. From the viewpoint of sufficiently exerting the effect of the liquid crystal display device of the present invention, Nz2 is preferably in the range of the optimum value side 8 (). R2 is preferably in the range of the optimum value (10) nm. The N 2 2 of the second second birefringent layer and the second second birefringent layer may satisfy the above range independently of each other as long as the difference between the two is not reached. Further, R2 of the first second birefringent layer and R2 of the second second birefringent layer may satisfy the above range independently of each other as long as the difference between the two is less than 20 nm. Further, if the Nz coefficient Nzql and the Nz coefficient Nzq2 are independently processed, the design of the phase difference = 163390.doc -55 - 201243449 will become extremely complicated. Therefore, the optimum Nz2 and R2 of the first and second second birefringent layers can be calculated using the average value Nzq to be extremely significant. Further, according to Table 4 and Fig. 17, in the range of Nzq < 2.00, the optimum value of Nz2 is 0 < Νζ 2 < The birefringent layer exhibiting the Nz coefficient in the range satisfies the biaxial retardation film of the relationship of nx > nz > ny, and thus is not suitable for the second birefringent layer, and is more difficult to manufacture than the second birefringent layer. High cost film. Furthermore, in terms of solving this point, it is preferable to satisfy 2.00 SNzq. The present inventors have studied the method of realizing a liquid crystal display having a relatively high contrast ratio in a wide range of viewing angles at a lower cost and in a simple manner for the range of Nzq <2.00. As a result, it was found that, in the case of Nzq < 2.00, if the second birefringent layer of Nz2 = 0 is used instead of the birefringent layer satisfying the optimum Nz2, R2 shown in Table 4, Fig. 17, and Fig. 18, The viewing angle characteristics can be effectively improved without using a biaxial retardation film controlled to nx > nz > ny (0< Nz < l). The best R2 corresponding to each Nzq is denoted as R2' and is shown in Table 4 and Fig. 19. From the viewpoint of sufficiently exerting the effect of the liquid crystal display device of the present invention, it is preferable to satisfy -0.80^Νζ2^0 (the optimum value is -0.80 or more and 0 (=optimal value) or less), and the 5 nm SR2S133 is satisfied. Nm (the best value is in the range of 40 nm). 163390.doc -56- 201243449 [Table 4]

Nzq Nz2 R2(nm) R2'(nm) 1.0 0.65 180 45 1.1 0.60 162 53 1.2 0.60 158 60 1.3 0.55 147 65 1.4 0.50 138 71 1.5 0.40 123 75 1.6 0.35 118 80 1.7 0.25 108 84 2.0 -0.05 89 93 2.3 - 0.40 77 2.4 -0.55 73 2.5 -0.70 69 2.6 -0.80 68 2.7 -1.00 64 2.8 -1.40 59 2.9 -2.45 49

代表 Representative examples of the liquid crystal display device of the present invention and the liquid crystal display of the present invention are shown below. (Supplementary Note 1) A liquid crystal display device which, when defining a police refractive layer satisfying the relationship of nx > ny^nZ, as the first birefringent layer, includes: a first polarizing element; a first λ/4 plate, The in-plane phase difference is adjusted to χ/4; the liquid crystal cell has a pair of substrates facing each other and a liquid crystal layer sandwiched between the pair of substrates; and the second λ-plate has a difference from the first λΜ The Νζ coefficient of the plate, and the in-plane phase difference is adjusted to λ/4; and the second polarizing element; and the first 163390.doc -57-201243449 and the second λ/4 plate are the first birefringent layer The orientation of the absorption axis of the second polarizing element is defined as 〇. At the time, the in-plane slow axis of the second person/4 plate is approximately 45. The angle 'the in-plane slow axis of the first λ/4 plate is approximately 135. The angle of the absorption of the first polarizing element is approximately 9 Å. In view of the above, the liquid crystal display device changes the display luminance by changing the state in which the liquid crystal molecules in the liquid crystal layer are substantially vertically aligned from the substrate surface to the state of the oblique alignment, and the liquid crystal layer includes the liquid crystal molecules at 125. ~32 5. The area of the azimuth oblique alignment and the liquid crystal molecules are at 1 〇2.5. ~122.5. The region of the azimuth oblique alignment, the liquid crystal molecules at 192.5. ~212.5. The area of the azimuth tilt alignment and the liquid crystal molecules are at 282.5. ~302.5. The area of the azimuth tilt alignment. (Supplementary Note 2) The liquid crystal display device of the first aspect, wherein one of the first λ/4 plate and the second λ/4 plate has a 2Νζ coefficient of 2 or more, and the first λ/4 plate and the second The other one of the λ/4 plates has a Νζ coefficient of 1 or more and less than 2. (Supplementary Note 3) The liquid crystal display device according to the first or second aspect, wherein the first and second/fourth plates have a larger twist factor in the back side of the liquid crystal cell. (Supplementary note 4) The liquid crystal display device according to any one of the preceding claims, wherein the first λ/4 plate has a Νζ coefficient greater than a Νζ coefficient of the second λ/4 plate, and is observed by the second polarizing element The face side in turn includes a surface treatment layer. The liquid crystal display device according to any one of the preceding claims, wherein the birefringent layer satisfying the relationship of ηΧ <ηγηΖ is defined as the second birefringent layer at 163390.doc -58- 201243449 The λ/4 plate and the first polarizing element further include two birefringent layers ′ and the in-plane axis of the second birefringent layer is substantially orthogonal to the absorption axis of the (four) first polarizing element. (Supplementary Note 6) The liquid crystal display device of the fifth aspect, wherein the second birefringent layer is disposed on a back side of the liquid crystal cell. (Supplementary note 7) The liquid crystal display device of the sixth aspect, wherein the first λ/4 plate has a Νζ coefficient greater than a Νζ coefficient of the second W4 plate, and the second birefringent layer and the first λ/4 plate It is disposed on the back side of the liquid crystal cell. (Attachment 8) The liquid crystal display device according to any one of the items 5 to 7, wherein the birefringent layer satisfying the relationship of nx and ny2nz is defined as the third birefringent layer, and the first λ/4 plate is At least one of the liquid crystal cells and between the liquid crystal cell and the second λ/4 plate further includes at least one layer of a third birefringent layer. (Supplementary Note 9) The liquid crystal display device of the eighth aspect, wherein the at least one layer of the third birefringent layer is disposed on the back side of the liquid crystal cell. (Supplementary note 10) The liquid crystal display device of the eighth aspect, wherein the first λ/4 plate has a Νζ coefficient greater than the λ coefficient of the second λ/4 plate, and the second birefringent layer, the first λ/4 The plate and the at least one layer of the third birefringent layer are disposed on the back side of the liquid crystal cell. The liquid crystal display device according to any one of claims 8 to 10, wherein the average value of the Nz coefficients of the first and second λ/4 plates is defined as Nzq, The thickness direction phase difference at the time of black display of the liquid crystal cell is defined as Rlc, and when the sum of the thickness direction phase differences of the at least one third type of birefringent layer is defined as R3, the following formulas (1) to (3), 1.0 are satisfied. <Nzq<2.9 (1) (169 nmxNzq-81 nm)-50 nm<Rlc+R3 (2)

Rlc+R3<(169 nmxNzq-81 nm)+50 nm (3). (Supplementary Note 12) The liquid crystal display device according to the ninth aspect, wherein the Nz coefficient of the second birefringent layer is defined as Nz2, and the in-plane phase difference is defined as R2, the following formulas (4) to (7) are satisfied. , (-0.63 xNzq2+0.56 xNzq+0.40)-0.80<Nz2 (4)

Nz2<(-0.63xNzq2 + 0.56xNzq+0.40)+0.80 (5) (43 nmxNzq2-226 nmxNzq+370 nm)-50 nm<R2 (6) R2<(43 nmxNzq2-226 nmxNzq+370 nm)+50 nm (7). (Supplementary Note 13) The liquid crystal display device of Attachment 12, in which 1.40 $ Nzq is satisfied. (Supplementary note 14) The liquid crystal display device according to any one of the preceding claims, wherein the average of the Nz coefficients of the first and second λ/4 plates is defined as Nzq, and the second birefringent layer is The Nz coefficient is defined as Nz2, and when the in-plane phase difference is defined as R2, Nzq<1.40 is satisfied, -0.80£Νζ2<0 is satisfied, and 88 163390.doc -60-201243449 nm$R2:Sl 88 nm is satisfied. (Supplementary Note 15) The liquid crystal display device according to any one of the items 5 to 7, wherein the birefringent layer satisfying the relationship of nx and ny > nz is defined as the third birefringent layer, and the first λ/4 is A third birefringent layer is not included between the plate and the liquid crystal cell and between the liquid crystal cell and the second λ/4 plate. (Supplementary note 16) The liquid crystal display device of claim 15, wherein the average value of the Νζ coefficients of the first and second λ/4 plates is defined as Nzq, and the thickness direction phase difference when the black cells of the liquid crystal cells are displayed is defined When Rlc is satisfied, the following formulas (1), (8), and (9), 1.0 < Nzq < 2.9 (1) (169 nm x Nzq - 81 nm) - 50 nm < Rlc (8)

Rlc<(169 nmxNzq-81 nm)+50 nm (9). (Supplementary Note 17) The liquid crystal display device according to supplementary note 16, wherein the enthalpy coefficient of the second birefringent layer is defined as Nz2, and the in-plane phase difference is defined as R2, the following formulas (4) to (7) are satisfied. , (-0.63xNzq2 + 0.5 6xNzq+0.40)-0.80<Nz2 (4)

Nz2<(-0.63 xNzq2+0.56><Nzq+0.40)+0.80 (5) (43 nmxNzq2-226 nmxNzq+370 nm)-50 nm<R2 (6) R2<(43 nmxNzq2-226 nmxNzq+370 nm ) +50 nm (7) 0 (Supplementary Note 18) The liquid crystal display device of Attachment 17, which satisfies 1.40^Nzq. 163390.doc -61 - 201243449 (Supplementary Note 19) The liquid crystal display device of Annex 15 or 16 wherein the average of the Nz coefficients of the above-mentioned first and second λ/4 plates is defined as Nzq, the second type of double The Nz coefficient of the refractive layer is defined as Nz2, and when the in-plane phase difference is defined as the ruler 2, Nzq<1.40 ' satisfies -〇.8〇sNz2^) and satisfies 88 nmSR2$188 nm ° (attachment 20). The liquid crystal display device according to any one of the preceding claims, wherein, when the average value of the Nz coefficients of the first and second λ/4 plates is defined as Nzq, Nzq < 2.00 is satisfied. The liquid crystal display device according to any one of the preceding claims, wherein the average value of the Nz coefficients of the first and second λ/4 plates is defined as Nzq, and 2.0 〇 SNzq is satisfied. (Supplementary Note 22) The liquid crystal display device of any one of 1 to 4, wherein when the birefringent layer satisfying the relationship of ηχ <ηγηζ is defined as the second birefringent layer, the first λ/ a first second birefringent layer between the fourth plate and the first polarizing element, and a second second birefringent layer between the second λ/4 plate and the second polarizing element, and the first The in-plane axis of the second birefringent layer is substantially orthogonal with respect to the absorption axis of the first polarizing element, and the in-plane axis of the second second birefringent layer is opposite to the second polarizing element The absorption axes are substantially orthogonal. (Supplementary note 23) 163390.doc. The method of claim 22, wherein the Nz coefficient and the in-plane phase difference of the second second birefringent layer are respectively different from the first second birefringent layer. The Nz coefficient and the in-plane phase difference are substantially the same. (Supplementary Note 24). The liquid crystal display device according to supplementary note 22 or 23, wherein the birefringent layer satisfying the relationship between nx and n^nz is defined as the third birefringent layer, the first λ/4 plate and the above At least one of the liquid crystal cells and between the liquid crystal cell and the second λ/4 plate further includes at least one layer of a third birefringent layer. (Supplementary Note 25) The liquid crystal display device according to supplementary note 24, wherein the at least one layer of the third birefringent layer is disposed on a back side of the liquid crystal cell. (Supplementary note 26) The liquid crystal display device of claim 25, wherein a coefficient of the first λ/4 plate is greater than an Nz coefficient of the second λ/4 plate, and the first λ/4 plate and the Q layer are at least one layer Three types of birefringent layers are disposed on the back side of the liquid crystal cell. (Supplementary Note 27) The liquid crystal display device according to any one of Claims 24 to 26, wherein the average value of the Nz coefficients of the first and second λ/4 plates is defined as Nzq, and the black color of the liquid crystal cell is displayed When the thickness direction phase difference is defined as Rlc ' and the sum of the thickness direction phase differences of the at least one layer of the third birefringent layer is defined as R3, the following formula 1.0 < Nzq < 2.9 (1) 163390.doc -63 - 201243449 ( 169 nmxNzq-81 nm)-50 nm<Rlc+R3 (2)

Rlc+R3<(169 nm><Nzq-81 nm) + 50 nm (3). (Supplementary note 28) The liquid crystal display device of claim 27, wherein the Nz coefficient and the in-plane phase difference of the second second birefringent layer and the Nz coefficient and the in-plane phase of the first second birefringent layer, respectively The difference is substantially the same, and when the Nz coefficient of the first and second second birefringent layers is defined as Nz2, and the in-plane phase difference is defined as R2, the following formulas (10) to (13) are satisfied, ( -0.87xNzq2+2.15 xNzq-0.76)-0.80<Nz2 (10)

Nz2 <(-0.87xNzq2+2.15xNzq-0.76)+0.80 (11) (25 nmxNzq2-159 nmxNzq+311 nm)-40 nm<R2 (12) R2<(25 nm><Nzq2-159 nm><<> Nzq + 311 nm) + 40 nm (13). (Supplementary Note 29) The liquid crystal display device of any one of the second to fourth aspect, wherein the Nz coefficient and the in-plane phase difference of the second second birefringent layer are respectively different from the first second birefringent layer The Nz coefficient and the in-plane phase difference are substantially the same, and the Nz coefficient of the first and second second birefringent layers is defined by defining an average value of the Nz coefficients of the first and second λ/4 plates as Nzq Defined as Nz2, and when the in-plane phase difference is defined as R2, it satisfies Nzq<2.00, satisfies -0.80$Nz2S0, and satisfies 5 nm$R2; ^ 13 3 nm 〇 (Note 30) Liquid crystal display as shown in Note 22 or 23 a device in which a birefringent layer satisfying a relationship of nx and ny2nz is defined as a third birefringent layer, between the first λ/4 plate and the liquid crystal cell, and the liquid crystal cell 163390.doc -64-201243449 A third birefringent layer is not included between the second λ/4 plate described above. (Supplementary note 31) The liquid crystal display device of claim 30, wherein the average value of the Νζ coefficients of the first and second λ/4 plates is defined as Nzq, and the thickness direction phase difference when the black cells of the liquid crystal cells are displayed is defined When Rlc is satisfied, the following formulas (1), '(8), and (9), 1.0<Nzq<2.9 (1) (169 nmxNzq-81 nm)-50 nm<Rlc (8) ζ) are satisfied.

Rlc<(169 nmxNzq-81 nm)+50 nm (9) ° (Supplementary Note 32) The liquid crystal display device according to supplementary note 3, wherein the second coefficient of the second birefringent layer and the in-plane phase difference are respectively The first second birefringent layer has substantially the same Νζ coefficient and the in-plane phase difference, and defines the Νζ coefficient of the first and second second birefringent layers as Νζ2, and the in-plane phase difference When defined as R2, the following formulas (10) to (13) are satisfied, ❹ (-0.87xNzq2+2.15 xNzq-0.76)-0.80<Nz2 (10)

Nz2<(-0.87xNzq2+2.15xNzq-0.76)+0.80 (11) (25 nm><Nzq2-159 nmxNzq+311 nm)-40 nm<R2 (12) . R2<(25 nmxNzq2-159 nmxNzq+311 Nm) +40 nm (13). (Supplementary note 33) The liquid crystal display device according to supplementary note 30 or 31, wherein a Νζ coefficient and an in-plane phase difference of the second second birefringent layer are respectively different from a first coefficient and a surface of the first second birefringent layer The internal phase differences are substantially the same, and the average value of the first and second λ/4 plates is defined as Nzq, and the first 163390.doc -65 - 201243449 and the second second birefringent layer are The Nz coefficient is defined as Nz2, and when the in-plane phase difference is defined as R2, 'satisfying Nzq<2.〇〇, satisfying _〇.8〇$Nz2s〇, and satisfying 5 nm$R2$133 nm. (Supplementary note 34) The liquid crystal display device according to any one of claims 24 to 29, wherein when the average value of the Nz coefficients of the first and second λ/4 plates is defined as Nzq, Nzq<2. (Note 35)

The liquid crystal display device of any one of 30 to 33, wherein the average value of the Nz coefficients of the upper first and second λ/4 plates is defined as N, full 2. 〇〇 SNz; q 〇 Each form may also be carried out without departing from the scope of the invention. Further, a state in which two or more preferred embodiments are combined with each other is also one of preferable embodiments. Advantageous Effects of Invention According to the present invention, it is possible to provide a cost-saving and excellent productivity.

The gray-scale viewing angle of the middle gray scale to the high gray scale is excellent: for outdoor use type liquid crystal display devices. The liquid crystal display device can preferably be a display device such as a sign display. [Embodiment] (Birefringent layer) The birefringence used in the present invention is not particularly limited. For example, it can be formed by fixing the material or the optical negative crystal material. , including thin sheets of inorganic materials. Ten I63390.doc -66 - 201243449=Double fold=layer formation method There is no special position, and the method of selecting the most sinfulness can be selected according to the design conditions. In the case of including a birefringent layer of a polymer film, for example, a solvent washing method, a solution extrusion method, or the like can be used. A method of simultaneously forming a plurality of birefringent layers by a co-extrusion method can also be used. As long as the desired phase difference is present, there can be no extension or extension. The stretching method is also not particularly limited, and can be used for heat shrinkage in addition to the roll stretching method, the inter-compression stretching method, the tenter transverse uniaxial stretching method, the oblique stretching method, and the vertical and horizontal double-axis ◎ stretching method. A special extension method for stretching under the action of the contraction force of the film. Further, in the case of a birefringent layer comprising a liquid crystal material, for example, a method of applying a liquid crystal material to a substrate film subjected to an alignment treatment and performing alignment fixation may be employed. As long as the desired phase difference is exhibited, it may be a method in which the base film is not subjected to a special alignment treatment, or a method in which the substrate film is peeled off from the base film after the alignment is fixed, and the film is transferred to another film. Further, a method of not fixing the alignment of the liquid crystal material can be used. Further, in the case of including a birefringent layer of a non-liquid crystalline material, the same formation method as that of the birefringent layer including the liquid crystalline material can be used. The first and second λ/4 plates are substantially 45 with respect to the polarizing element in order to constitute the circular polarizing plate. Since the layers are laminated at a relative angle, it is preferable to use an oblique stretching method in which the oblique direction is aligned with respect to the longitudinal direction of the roll film. Especially for the λ/4 plate having a smaller Νζ coefficient, it is preferable to use the oblique stretching method. On the other hand, for the λ/4 plate having a larger Νζ coefficient, it is preferable to use the oblique stretching method as much as possible. When the method cannot be used, the above other methods can be appropriately selected. The following description will be further specifically described by the type of the birefringent layer. (First Birefringent Layer: First and Second λ/4 Plates) 163390.doc •67· 201243449 As the first birefringent layer, a film containing a material having a positive birefringence as a component can be suitably used. Extend and defend the founder and so on. Examples of the material having a positive intrinsic birefringence include, for example, polycarbonate, polysulfone, polyether hard polyparaphenylene phthalate, polyethylene, polyvinyl alcohol, borneol, triacetyl cellulose, and Acetyl cellulose and the like. (Second Birefringent Layer) As the second birefringent layer, a film containing a material having a negative intrinsic birefringence as a component can be suitably used, and the shrinkage force of the heat-shrinkable film can be suitably used. The method of extending and curing a film containing a material having a positive intrinsic birefringence as a component is particularly advantageous from the viewpoint of simplification of the manufacturing method. It is preferable to carry out a film containing a material having a negative intrinsic birefringence as a component. Extended processing. The material which is negative in the intrinsic birefringence is exemplified by a resin composition containing an acrylic resin and a styrene resin, polystyrene, polyethylene naphthalene, polyethylene biphenyl, and ethylene. Bipyridine, polymethyl methacrylate, polymethyl acrylate, hydrazine-substituted maleimide copolymer, polycarbonate with fluorene skeleton, triacetyl cellulose (especially those with less acetylation) . In particular, a resin composition containing an acrylic resin and a styrene resin is preferred from the viewpoint of optical properties, productivity, and heat resistance. A method for producing such a film comprising a resin composition as a component is disclosed, for example, in Patent Document 9. (Third Birefringent Layer) As the third birefringent layer, a film containing a material having a positive birefringence as a component can be suitably used for longitudinal and transverse biaxial stretching, and a cholesteric shape is applied. Liquid crystal material such as liquid crystal or disk type liquid crystal, and 163390. doc-68-201243449, a non-liquid crystal material containing a polyimine or polyamine, or the like. (Polarizing element) As the polarizing element, for example, an anisotropic material such as a mis-filled material having dichroism can be suitably used to be adsorbed on a polyvinyl alcohol (PVA) film. (liquid crystal cell)

The liquid crystal cell divides the tilt direction of the liquid crystal molecules into a plurality of alignment division type VA modes in the pixel, that is, a so-called MVA mode (Muhi_d〇main VA. multi-domain type va mode), and by liquid crystal molecules in the liquid crystal layer The alignment is black display perpendicular to the substrate surface. In other words, in addition to the TFT method (active matrix method), the driving method of the liquid crystal cell may be a simple matrix method (passive matrix method) or a plasma addressing method. As an example of the configuration of the liquid crystal cell, it is shown that the liquid crystal layer is sandwiched between the substrates by one of the electrodes, and a voltage is applied between the electrodes. (Surface Treatment Layer) As the surface treatment layer, the following three types are mainly hard-coat layers for preventing damage, and the second type is a Ke (10)-'anti-glare layer for imparting anti-glare properties, and third. The anti-reflection layer is used to reduce surface reflection. Examples of the anti-inverse (four)' include an AR (Anti ― (10), anti-reflection) layer having a low reflectance, a owe region ‘low reflection layer having a higher reflectance than the AR layer, and a moth eye layer having a very low reflectance. Further, the surface treatment layer is usually formed on a transparent bite film (for example, a TAC film;). Further, a plurality of surface treatment layers may be laminated as such a laminate. For example, 163390.doc -69 - 201243449 may be cited as an AGLR (Anti Glare-Low Reflection) with an AG layer laminated on the LR layer. The layer, the AGAR (Anti Glare-Anti Reflection) layer of the AG layer is laminated on the AR layer. The observation side circular polarizing plate is preferably produced by a continuous winding technique using a protective film with a surface treatment layer, a polarizing element, and a smaller one in the first and second λ/4 plates. (Measurement Method of R, Rth, Νζ Coefficient, nx, ny, ηζ) The measurement was performed using a dual-rotating retarder type polarimeter (manufactured by Axometrics, trade name: Axo-scan). The in-plane phase difference R is measured from the normal direction of the birefringent layer. The main refractive index nx, ny, ηζ, the thickness direction phase difference Rth, and the Νζ coefficient are measured by the phase difference from the normal direction of the birefringent layer and the inclination from the normal direction by -50° to 50°. It is calculated by curve fitting of a well-known refractive index ellipsoid. The tilt orientation is the orientation orthogonal to the in-plane slow phase axis. Further, nx, ny, ηζ, Rxz, and Νζ are average refractive indices provided by the calculation conditions of the curve fitting = (nx + ny + nz) / 3, and the average refractive index of each birefringent layer is unified to 1.5. Calculation. For a birefringent layer having an actual average refractive index of not 1.5, the average refractive index is also assumed to be 1.5. (Method for Measuring Contrast-Viewing Angle Characteristics of Liquid Crystal Display Device) Measurement was carried out using a viewing angle measuring device (manufactured by ELDIM Co., Ltd., trade name: EZ Contrastl 60). The light source is a backlight of a liquid crystal television (trade name: LC37-GH1) manufactured by Sharp Corporation. Determine the orientation 45. The brightness of the white display in the oblique direction of 60° and the brightness of the black display are set to CR (45, 60). Also, the orientation 0 is measured. The white of the oblique 60° is 163390.doc -70- 201243449 The shell of the black display is displayed, and the ratio is set to CR (〇, 6〇). The present invention will be further described in detail by the following examples, but the invention is not limited to the examples. Embodiments 1 to 3, 7 and Comparative Example 3 The liquid crystal display devices of Embodiments 1 to 3 and 7 of the present invention and the liquid crystal display device of Comparative Example 3 are sequentially laminated with a backlight (not shown) as shown in FIG. a first polarizing element 410, a second birefringent layer 415, a first λ/4 plate (first birefringent layer) 420, a VA mode liquid crystal cell 43A, a second λ/4 plate 44A, and a second polarizing element A circularly polarized VA mode liquid crystal display device 4 obtained in 450. That is, the liquid crystal display device 4 of Fig. 20 is different from the liquid crystal display device 3 of Fig. 7 in that the third birefringent layer is not included. In the embodiments 丨~3, 7, the Nz coefficient of the first λ/4 plate 420 and the second λ/4 plate 44〇iNz coefficient are different from each other, but in the comparative example 3, the 'first λ/4 plate 420 The Nz coefficient is set to be the same as the second coefficient of the second λ/4 plate 440. Furthermore, in FIG. 2A, the front heads depicted in the first and second polarizing elements 410, 450 indicate the orientation of the absorption axis, and the arrows depicted in the first and second λ/4 plates 420, 44A are Indicates the orientation of the slow axis, and the arrow depicted in the second birefringent layer 41 5 indicates the orientation of the phase axis. The ellipsoid depicted in the VA mode liquid crystal cell 430 represents the shape of the index ellipsoid. . The liquid crystal cell 430 includes a thin film transistor (TFT) substrate, a color filter (CF) substrate, and a liquid crystal layer sandwiched therebetween. A vertical alignment film is disposed on the surface of the TFT substrate and the color filter substrate on the liquid crystal layer side, and an electrode is provided on the lower layer (substrate side) of each of the vertical alignment films. The alignment of the liquid crystal molecules is controlled by applying a desired voltage to the liquid crystal I63390.doc-71·201243449 layer by the electrodes of the TFT substrate and the electrodes of the color filter substrate. The liquid crystal layer contains liquid crystal molecules having a negative dielectric anisotropy. Therefore, in a state where no voltage is applied to the liquid crystal layer (off state), the liquid crystal molecules are aligned substantially perpendicularly to the surface of the vertical alignment film, and a state in which a voltage of a threshold voltage or more is applied to the liquid crystal layer (on state) is ' The liquid crystal molecules are tilted horizontally with respect to the surface of the vertical alignment film. Since the absorption axes of the first polarizing element 4 ι and the second polarizing element 450 are arranged to be orthogonal to each other (orthogonal polarization arrangement), the liquid crystal display device 400 performs black display in the off state. The liquid crystal cell 430 is a so-called liquid crystal cell of the MVA mode (multi-domain type VA mode) and has four regions in the pixel. The asymmetry of the tilting orientation can be effectively offset by the fact that the tilting directions of the four regions are in a substantially orthogonal relationship with each other when viewed from the front side. In the circular polarization mode, since the circularly polarized light is incident on the liquid crystal cell 43〇, the display is limited to the liquid crystal cell in the front direction (the normal direction with respect to the display screen). Penetration rate, but in the oblique direction, the tilting orientation of the liquid crystal molecules affects the transmittance of the liquid crystal cell. Therefore, by controlling the tilting orientation in the four regions, the grayscale viewing angle in the oblique direction can be improved. In the liquid crystal cell 430, as shown in Fig. 21, a liquid crystal is formed in each pixel to be 22.5. The region of the azimuth oblique alignment, the liquid crystal molecules are obliquely aligned in the 112.5° direction, and the liquid crystal molecules are at 2〇25. The orientation is obliquely aligned to the region 1) 3 and the liquid crystal molecules are at 292.5. Four areas in which the azimuth is inclined to the area D4. In order to improve the viewing angle characteristics, as shown in the figure, the four regions can be divided into two regions to which different voltages can be applied. 163390.doc -72- 201243449 In Fig. 22, a total is formed in the pixel. 8 regions, but for regions containing liquid crystal molecules having different polar angles, as long as the tilt directions are substantially the same as each other, they are also contained in the same region, so the number of regions is four. That is, regions D1 -1 and D1 -2 Although the polar angles of the liquid crystal molecules are different, the tilt orientations are 22.5 in common. Although the polar angles of the liquid crystal molecules are different in the regions D2-1 and D2-2, the tilt orientations are 112.5. The regions D3-1 and D3-2 are liquid crystal molecules. The polar angles are different but the tilting orientation is 202.5. The regions D4-1 and D4-2 have different polar angles of the liquid crystal molecules but the tilting orientation is 292.5. The 〇 and ' can also increase the number of pixels to more than four. For example, the liquid crystal unit 430 may be one pixel including a plurality of sub-pixels. In this case, the four regions as described above may be disposed one by one in each sub-pixel. In the liquid crystal unit 430 Control of tilt orientation of liquid crystal molecules The alignment control mechanism is formed by at least one of a TFT substrate and a CF substrate. The alignment control mechanism is not particularly limited, and examples thereof include a slit formed on the electrode of the substrate and a CF substrate. a combination of linearly extending dielectric protrusions formed on the lower layer (substrate side) of the vertical alignment film. At this time, the tilt orientation of the liquid crystal molecules in each region can be adjusted by adjusting the extension orientation and dielectric of the slit The orientation of the protuberances is controlled by the extending direction of the protuberances, and the stomach can be controlled by adjusting the orientation of the first polarizing element 410 and the like. Further, the tilting orientation of the liquid crystal molecules may be set on the TFT substrate and the CF substrate. The electric field generated by the influence of the upper electrode or the wiring, or the surface shape of the liquid crystal layer side of the tft substrate and the CF substrate, etc., deviates from the desired orientation 163390.doc • 73· 201243449. In the liquid crystal display device of the present invention If the liquid crystal molecules are included in the 22.5° azimuth oblique alignment region D1, the liquid crystal molecules are at 112.5. The azimuthal oblique alignment region D2 and the liquid crystal molecules are at 202.5. Azimuth tilt alignment The region D3 and the liquid crystal molecules are formed in the pixel at 292.5. The four regions of the azimuth oblique alignment region D4 are also included in the region D5, D6, and D7 due to poor alignment as shown in FIG. Embodiments 4 to 6 The liquid crystal display devices of Embodiments 4 to 6 of the present invention sequentially stack a backlight (not shown), a first polarizing element 51, and a first second as shown in FIG. Birefringent layer 5 15, first λ/4 plate (first birefringent layer) 52 〇, third birefringent layer 535, MVA mode liquid crystal cell 530, second λ/4 plate 54 〇, second A circularly polarized VA mode liquid crystal display device 5 obtained by the second birefringent layer 545 and the second polarizing element 550. That is, the liquid crystal display device 5 of Fig. 24 is different from the liquid crystal display device 3 of Fig. 11 in that it includes two second birefringent layer aspects. In the fourth to sixth embodiments, the coefficient of the first λ/4 plate 52〇iNz and the coefficient of the second λ/4 plate 540 are different from each other. The liquid crystal cell 53A has the same configuration as that of the liquid crystal cell 430 of the first embodiment, and includes a region in which liquid crystal molecules are obliquely aligned in a 22.5° direction, and liquid crystal molecules are at 112 5 . The area of the azimuth tilt alignment and the liquid crystal molecules are at 202.5. The area of the azimuth tilt alignment and the liquid crystal molecules are at 292.5. Four regions of the azimuth oblique alignment region are formed in each pixel. Further, in Fig. 24, the arrows drawn in the first and second polarizing elements 51A, 55B indicate the orientation of the absorption axis, and the arrows depicted in the first and second/input plates 520, 540 are Indicates the orientation of the slow axis, and the arrows depicted in the first and second second birefringent layers 515, 545 represent the orientation of the phase axis, liquid crystal cell 530 and third, 163390.doc -74 - 201243449 The ellipsoid depicted in the birefringent layer 535 represents the shape of its index ellipsoid. Comparative Example 1 A liquid crystal display device of Comparative Example 1 sequentially laminated a backlight (not shown), a first polarizing element 610, a first λ/4 plate (first birefringent layer) 620, and MVA as shown in FIG. A circularly polarized VA mode liquid crystal display device 600 obtained by a mode liquid crystal cell 630, a second λ/4 plate 640, a second birefringent layer 645, and a second polarizing element 650. In Comparative Example 1, the Νζ coefficient of the first λ/4 plate 620 and the Νζ coefficient of the second λ/4 plate 640 are set to be the same. The liquid crystal cell 630 has the same configuration as the liquid crystal cell 430 of the first embodiment, and includes a region in which the liquid crystal molecules are obliquely aligned at a direction of 22.5°, a region in which the liquid crystal molecules are obliquely aligned at an azimuth of 112.5°, and a region in which the liquid crystal molecules are obliquely aligned at a direction of 202.5°. And four regions in which the liquid crystal molecules are obliquely aligned in the azimuth of 292.5° are formed in each pixel. Further, in Fig. 25, the arrows drawn in the first and second polarizing elements 610, 650 indicate the orientation of the absorption axis, and the arrows depicted in the first and second λ/4 plates 620, 640 indicate The orientation of the slow phase axis, the arrow depicted in the second birefringent layer 645 indicates the orientation of the phase axis, and the ellipsoid depicted in the liquid crystal cell 630 indicates the shape of its index ellipsoid. Comparative Example 2 The liquid crystal display device of Comparative Example 2 sequentially laminated a backlight (not shown), a first polarizing element 710, a first second birefringent layer 715, and a first λ/4 plate as shown in FIG. (first birefringent layer) 720, MVA mode liquid crystal cell 730, third birefringent layer 735, second λ/4 plate 740, second second 163390.doc -75- 201243449 birefringent layer 745 And a circularly polarized liquid crystal display device 700 obtained by the second polarizing element 75 (four). In Comparative Example 2, the coefficient of the first λ/4 plate 72 is set to be the same as the coefficient of the second λ/4 plate 740. The liquid crystal cell 73A has the same configuration as that of the liquid crystal cell 430 of Embodiment 1, and includes liquid crystal molecules at 22.5. The region of the obliquely oriented alignment and the liquid crystal molecules are at ιΐ25. The area of the oblique tilting alignment and the liquid crystal molecules are at 202.5. The region of the azimuth oblique alignment and the liquid crystal molecules are at 292.5. The four regions of the region of the azimuth oblique alignment are formed in each pixel. Further, in Fig. 26, the arrows drawn in the first and second polarizing elements 710, 750 indicate the orientation of the absorption axis, and the arrows depicted in the first and second λ/4 plates 720, 740 indicate The orientation of the slow phase axes, the arrows depicted in the first and second second birefringent layers 715, 745 indicate the orientation of the phase axes thereof, as depicted in the liquid crystal cell 730 and the third birefringent layer 735. The ellipsoid indicates the shape of its index ellipsoid.

The material names, the axial angles, the in-plane retardation R, the thickness direction retardation Rth, or the Rlc and the coefficient of the liquid crystal cell of the polarizing element, the birefringent layer, and the liquid crystal cell of each example are shown in Table 5 and 下述 below. In the table, the axis of each birefringent layer is defined by the azimuth of the in-plane retardation axis, and the axis of the polarizing element is defined by the azimuth of the absorption axis. Furthermore, with regard to the second birefringent layer, although the in-plane phase axis is more important in design, but in the table, like the other birefringent layers, the axis of the second birefringent layer is the in-plane retardation axis. Azimuth definition. The in-plane axis of the second birefringent layer is orthogonal to the in-plane slow axis of the second birefringent layer. Further, in the table, the material names of the respective birefringent layers are indicated by the following abbreviations. ΝΒ: norbornene PI (Polyimide): polyimine 163390.doc -76- 201243449 TAC : triethylene fluorene cellulose A. Resin composition containing acrylic resin and styrene resin and then 'in the table' Nz coefficient The average value is defined as the average of the coefficient of the first λ/4 plate and the Νζ coefficient of the second λ/4 plate. (Evaluation result) The contrast_viewing angle characteristics of the liquid crystal display devices of the respective examples were measured, and the orientation was 〇. The polar angle is 60. Contrast [CR (〇, 6〇)] and azimuth 45. The polar angle ❹ 60° contrast ratio [CR(45,6〇)] is arranged in Tables 5 and 6 below. The "azimuth X., polar angle γ. contrast under" refers to the X . In the azimuth, the angle of view is tilted from the normal direction by γ. The contrast measured in the direction. That is, the polar angle indicates the angle between the front direction and the viewing direction. Further, the (1) orientation of each example is 0. , the polar horns. , (2) Azimuth 0. The polar angle is 6 inches. And (3) azimuth 45. The gamma curve at the polar angle of 6 〇 is shown in Figures 27 to 36. The gamma curve represents the change in voltage with respect to the transmittance applied to the liquid crystal layer with the gray scale value as the horizontal axis and the normalized luminance as the vertical axis. Since the display Q mode of the liquid crystal display device of each example is normal black display, the black display corresponds to the grayscale value of 0, and the white display corresponds to the grayscale value of 256. The larger the grayscale value, the greater the voltage applied to the liquid crystal layer. . The standardization of the brightness is set to 1. When the grayscale value is 256, the brightness is set to 1. Usually, a plurality of gamma curves obtained from different measurement directions are compared with each other as an index indicating how different degrees of vision of the kneading surface are displayed according to the direction in which the liquid crystal display device is observed. The closer the difference is, the more consistent the visual display is. 0 The liquid crystal display devices of Embodiments 1 to 7 of the present invention are compared with cr (〇, 60) and 163390.doc -77· 201243449 CR (45, 60). The CR (0, 60) and CR (45, 60) of the example 3 are equivalent. Further, the gamma curves of the liquid crystal display devices of Examples 1 to 7 were the same as those of the liquid crystal display devices of Comparative Examples 1 to 3. In the visual evaluation of the liquid crystal display devices of Examples 1 to 7, the display quality in the oblique viewing angle was also excellent. Further, in the first to seventh embodiments, since the Nz coefficient of the first λ/4 plate and the Nz coefficient of the second λ/4 plate are different from each other, the circular eccentric light of the first χ/4 plate having a small NZ coefficient is included. The board is excellent in productivity and can reduce costs. In particular, since a λ/4 plate of a general product manufactured by oblique extension can be used as a λ/4 plate whose Νζ coefficient is adjusted to be approximately 1.6, an embodiment including a λ/4 plate whose Νζ coefficient is adjusted to approximately 1.6 is used. The advantages of production are enormous. Further, in the first to seventh embodiments, since the first λ/4 plate having a small enthalpy coefficient is disposed on the observation surface side of the liquid crystal cell, it is possible to improve the observation surface side which is likely to cause an increase in variety in response to different surface treatment requirements. The productivity of the polarizing plate (on the side of the second polarizing element). Further, in Examples 1 to 3 and 7, the second birefringent layer was disposed on the back side (backlight side) of the liquid crystal cell, and compared with Example 4 to ό, Examples 1 to 3 and 7 were observed. The polarizing plate on the surface side (the second polarizing element side) is simpler in composition, and thus has higher productivity. In Examples 4 to 6, the third birefringent layer was disposed on the meniscus side (backlight side) of the liquid crystal cell, compared to Comparative Example 2, Examples 4 to 6 due to the observation surface = (first-polarized element) The configuration of the polarizing plate of the side is simpler, so the productivity is further improved. In the liquid crystal display device of Comparative Example 3, the Nz coefficients of the first and second λ/4 plates are relatively large, and thus it is sometimes difficult to produce the first One and two λ/4 plates. As described above, the liquid crystal display device according to the present invention can ensure extremely excellent display quality in the squint 163390.doc -78 - 201243449 corner, and obtain various advantages in manufacturing [Table 5].

Optical member name Material name Axis angle [°] Phase difference [nm] Nz coefficient Nz coefficient average evaluation result R Rth or Rlc CR (45, 60) CR (0, 60) Example 1 Second polarizing element 0 2.09 57 174 Second λ/4 plate ΝΒ 45 138 1.10 VA mode liquid crystal cell (22.5° ' 112.5° ' 202.5° ' 292.5°) 290 First λ; 4 plate ΝΒ 135 138 3.08 Second birefringent layer A 90 85 • 1.21 A polarizing element 90 Embodiment 2 Second polarizing element 0 2.09 58 175 Second λ/4 plate ΝΒ 45 138 1.65 VA mode liquid crystal cell (22.5°, 112.5° ' 202.5° ' 292.5°) 290 First λ/4 plate ΝΒ 135 138 2.53 Second birefringent layer A 90 85 -1.21 First polarizing element 90 Example 3 Second polarizing element 0 2.08 58 174 Second W4 plate ΝΒ 45 138 1.98 VA mode liquid crystal cell (22.5°, 112.5°, 202 , 5°, 292.5.) 290 First λ/4 plate 135 135 138 2.18 Second birefringent layer A 90 85 -1.21 First polarizing element 90 Example 4 Second polarizing element 0 2.15 58 175 Second second Birefringent layer A 0 85 -0.10 Second W4 plate 45 138 1.10 VA mode liquid crystal cell (22.5°, 112.5., 202.5., 292.5.) 320 Third birefringent layer TAC 2 -52 First λ/4 plate 135 135 138 3.20 First second birefringent layer A 90 85 -0.10 First polarizing element 90 Embodiment 5 Second polarizing element 0 2.14 58 175 Second second birefringent layer A 0 85 0.10 Second V4 board NB 45 138 1.65 VA mode liquid crystal cell (22.5°, 112.5°, 202, 5°, 292.5°) 320 Third birefringent layer TAC 2 -52 First λ/4 plate NB 135 138 2.65 First second birefringent layer A 90 85 -0.10 First polarizing element 90 Example 6 Second polarizing element 0 2.13 59 176 Second second birefringent layer A 0 85 -0.10 Second λ/4 plate NB 45 138 1.98 VA mode liquid crystal cell (22.5°, 112.5. 202.5. 292.5. 320 third birefringent layer TAC 2 -52 first V4 plate NB 135 138 2.28 first second birefringent layer A 90 85 •0.10 first polarizing element 90 embodiment 7 second polarizing element 0 2.05 52 176 Second λ/4 plate NB 45 138 1.65 VA mode liquid crystal cell (22.5°, 112.5., 202.5., 292.5.) 310 First V4 plate NB 135 138 2.45 Second birefringent layer A 90 105 -0.45 First polarized light Element 90 79- 163390.doc 201243449 [Table 6] Optical member name Material name Axis angle [°] Phase difference [nm] Nz coefficient Nz coefficient average evaluation result R Rth or Rlc CR (45'60) CR (0, 60 Comparative Example 1 Second polarizing element 0 2.08 58 175 Second birefringent layer A 0 85 -1.21 Second slab NB 45 138 2.08 VA mode liquid crystal cell (22.5°, 112.5° '202.5°' 292.5°) 290 A λ/4 plate NB 135 138 2.08 First polarizing element 90 Comparative example 2 Second polarizing element 0 2.13 60 176 Second second birefringent layer A 0 85 -0.10 Second λ/4 plate NB 45 138 2.13 Three birefringent layers TAC 2 52 VA mode liquid crystal cell (22.5° ' 11 2.5° ' 202.5° ' 292.5°) 320 First λ/4 plate NB 135 138 2.13 First second birefringent layer A 90 85 -0.10 First polarizing element 90 Comparative example 3 Second polarizing element 0 2.00 52 176 Second W4 board NB 45 138 2.00 VA mode liquid crystal cell (22.5° ' 112.5°' 202.5°' 292.5°) 310 First λ/4 plate NB 135 138 2.00 Second birefringent layer A 90 105 -0.45 First polarized light Element 90 Further, since the liquid crystal display device of each of the embodiments has a circular polarizing plate including a combination of a linear polarizing plate (polarizing element) and a λ/4 plate on both sides of the liquid crystal cell, the liquid crystal display device is displayed in a circularly polarized light VA mode. In addition to the effect of improving the transmittance, the circularly polarized VA mode can also obtain an anti-reflection effect, which is effective for improving the contrast. The anti-reflection function of the circularly polarized VA mode is a light that is reflected in the liquid crystal display device when it is incident on the liquid crystal display device from the periphery of the liquid crystal display device by the action of the circular polarizing plate, that is, the reflected light generated by the so-called internal reflection. , does not emit outside the liquid crystal display device. Therefore, according to the circularly polarized VA mode, light reflected on the surface of the black matrix, the wiring, the electrode, or the like in the liquid crystal cell is not easily emitted to the outside of the liquid crystal display device, and in particular, the liquid crystal display device can be prevented from being bright in the surrounding environment (bright environment). The contrast is reduced. On the other hand, as the reflected light which reduces the contrast of the liquid crystal display device in a bright environment -80-163390.doc 201243449, in addition to the reflected light generated by the internal reflection described above, it is also possible not to be surrounded by the liquid crystal display device. Light that is incident on the surface of the liquid crystal display device and is reflected by the surface of the liquid crystal display device, that is, reflected light generated by surface reflection. As a result of suppressing the reflected light generated by the internal reflection in the liquid crystal display device of the circularly polarized VA mode, the reflection due to the surface reflection * the amount of light significantly affects the visibility of the display screen. Therefore, by implementing a countermeasure for reducing the reflected light generated by the surface reflection in the liquid crystal display device of the circularly polarized VA mode, an extremely high contrast can be obtained in a bright environment, and the observer who observes the display screen can actually feel the display quality. Significantly improved. The antireflection film (layer) for suppressing surface reflection includes an antireflection film formed by laminating a plurality of films having different refractive indices, and an antireflection film having fine protrusions and pits formed on the surface. In particular, the "Moth Eye film" which is one of the latter anti-reflection films has a structure in which a plurality of protrusions having a smaller wavelength (380 to 780 nm) than visible light are provided on the surface, so that the surface can be reflected. The suppression is extremely excellent. As shown in Fig. 37 (a), the light incident on the moth eye film reaches the film base portion 362 via the fine projections 361 provided on the surface, so that the projection is located between the air layer and the film base portion. The region mixed with the air layer (the region between A_b in the figure) can be regarded as 'intermediate refractive index of the refractive index of the material constituting the film (about 1.5 in the case of the resin film) and the refractive index (1 〇) of the air. The area of the rate. That is, as shown in Fig. 37 (b), the refractive index of the region corresponds to the change in the volume ratio of the protrusion and the air layer, and the refractive index of the air in contact with the surface of the film is within a distance shorter than the wavelength of visible light. The gradual increase gradually increases to the refractive index of the material constituting the film. As a result, the light incident on the moth eye film does not recognize the interface between the air-films 163390.doc -81 - 201243449 as an interface having a different refractive index, so that the reflection of light generated at the interface can be greatly suppressed. By the moth eye film, for example, the surface reflectance of visible light is about 0.15%. If the moth eye film is disposed at a different interface of the fold (four), the effect of reducing the reflectance can be exhibited. For example, in the configuration shown in FIG. U, the internal reflection generated inside the second polarizing element 350 can include the second polarized light. The combination of the component and the second λ/4 plate 340 is suppressed by the circular polarizing plate. Therefore, for example, in the case where the moth eye film is added to the configuration of FIG. 11, the moth eye film 360 as shown in FIG. 38 is disposed on the display surface side (viewing surface side) of the second polarizing element 35A. . In a case where a member such as a protective plate is disposed on the display surface side of the second polarizing element 35 (), a plurality of interfaces may be present, and a moth eye film may be provided for each interface, and at least the liquid crystal is preferably exposed to the liquid crystal. The outside of the display unit. Specific examples of the moth eye film include a resin film having a plurality of protrusions having a shape of a substantially circular shape having a height of about 2 Å at a distance of about 2 〇〇 (10). As a method of producing the moth eye film, a technique of transferring the shape of the rice which is engraved in the mold (1 to 4 (4) is applied to the resin material applied to the substrate to transfer the shape] is a so-called nano imprint technique. Examples of the method for hardening the resin material in the nanoimprint technique include a thermal imprint technique, an ultraviolet (9) travilet, and a uv) nanoimprint technique. The uv nanoimprint technique is to form a film of an ultraviolet curable resin on a transparent substrate, and press the mold on the thin mold, and then irradiate ultraviolet rays, thereby forming a moth eye structure having a reverse shape of the mold on the transparent substrate. film. 163390.doc •82- 201243449 砝 In order to manufacture a thin scorpion with a moth eye by a large number of inexpensive embossing techniques, it is preferred to use a continuous winding process as compared to batch processing. According to the continuous winding treatment, the film having the moth-eye structure can be continuously produced by using a mold roll. The mold is light, and the outer surface of the cylindrical or cylindrical tube can be formed by anodization. There are pits of nano size. The Genlang polar oxidation method can form a non-seam (floating) moth-eye structure suitable for continuous production on the surface of the mold roll by randomly and uniformly forming a pit of a non-meter size on the surface. The respective embodiments of the above-described embodiments may be combined as appropriate without departing from the spirit and scope of the invention. Further, a form in which two or more preferred embodiments are combined with each other is also one of preferable embodiments. This application is based on the patent application 2〇ιι_嶋128, filed on March 31, 2011, and claims the priority based on the Paris Convention and the regulations of the country of transfer. The entire content of the request is for reference and in the application. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a view showing an azimuth angle 沴 and a polar angle 朝向 with respect to the direction A of the oblique alignment of liquid crystal molecules. Fig. 2 is a perspective exploded view showing the configuration of a circularly polarized VA mode liquid crystal display device including the simplest configuration, which does not include the second and third birefringent layers. Fig. 3(a) is a schematic diagram of the late phase sleeve of the -λ/4 plate and the second phase of the second λ/4 plate orthogonal to the front direction, viewed from the front direction (above and self-orientation 0) The mode diagram (below) e (b) is for the front direction 163390.doc -83- 201243449 Orthogonal phase of the first λ Μ plate and the second λ / 4 plate of the slow phase axis The pattern diagram (top) when viewed from the front direction and the pattern diagram (bottom) when viewed from the oblique direction of the orientation 45. (勹 is the absorption axis of the first polarizing element orthogonal to the front direction and the second The absorption axis of the polarizing element, the mode diagram (top) when viewed from the front direction, and the mode diagram when the self-orientation 45 is obliquely observed (bottom). FIG. 4 is a circularly polarized VA mode liquid crystal display device of FIG. The state of the polarized state of the transmitted light when viewed from the front direction is projected on the S1_S2 plane of the Poincare sphere as it passes through each member. Fig. 5 is a circularly polarized VA mode liquid crystal display device of Fig. 2. , the self-direction 〇., the pole 60. When viewed obliquely, the transmitted light is polarized. The case where each member changes from time to time is projected on the plane of the Poincare sphere. Fig. 6 is an exploded perspective view showing the configuration of a circularly polarized va mode liquid crystal display device including a third birefringent layer. 6 circular polarized VA mode liquid crystal display device (Nzql=Nzq2=2_〇, R3=_61 nm, Rlc=32〇nm form), when viewed from the front direction, the transmitted light polarization state passes each The case where the component changes from time to time is shown in the S1-S2 plane of the Poincare sphere. Fig. 8-1 is the circularly polarized VA mode liquid crystal display device of Fig. 6 (Nzql Nzq2-2.〇, RXl nm, Rlc= The shape of 320 nm), which is observed from the azimuth 〇., the pole 60. The oblique state of the transmitted light changes as it passes through each member, and is projected on the Sli2 plane of the Poincare sphere. 8-2 is a circular polarized VA mode liquid crystal display device of FIG. 6 163390.doc •84·201243449 (NZql = 3.〇, Nzq2 spitting, R3t6l nm, η:·), and the self-orientation is 0. The polarized state of the transmitted light changes as it passes through the members when viewed obliquely. The shape projection is shown in the S1-S2 plane of the Poincare sphere. Fig. 8-3 is the circularly polarized VA mode liquid crystal display device of Fig. 6 (Nzq Bu 2.5, Nzpy.S, R3 = _61 nm, Rlc = 32 〇) The form of nm "will be from the azimuth 0., the pole 60. When viewed obliquely, the polarization of the transmitted light 投影 state changes as it passes through each member. The projection is represented on the S1-S2 plane of the Poincare sphere. Figure

8-4 is a circularly polarized VA mode liquid crystal display device for FIG.

The shape of Rlc=320 nm (Nzql = l.〇, Nzq2=3.0, R3=_61 nm state) will be from the orientation 0. Extreme 60. The state in which the polarized state of the transmitted light changes as it passes through the respective members is projected on the S1-S2 plane of the Magical Ball. 8-5 is a circularly polarized VA mode liquid crystal display device of FIG.

(Nzql = 1.5, Nzq2 = 2.5, R3 = _61 nm, Rlc = 320 nm), will be from the azimuth 0. Extreme 60. The state in which the polarized state of the transmitted light changes as it passes through the respective members is projected on the S1-S2 plane of the Poincare sphere. Fig. 8-6 is a circularly polarized VA mode liquid crystal display device of Fig. 6, which will be self-aligned to zero. Extreme 60. The oblique phase axes of the first and second λ/4 plates when viewed obliquely are projected on the 81_82 plane of the Poincare sphere as a function of the Νζ coefficient. 9 is a graph showing the average Nzq of the Nz coefficients of the first and second λ/4 plates and the thickness direction of the third birefringent layer for the circularly polarized νΑ mode liquid crystal display device of FIG. A graph of the relationship between the best values of the difference R3. Figure 10 is a perspective view of the circularly polarized VA mode liquid crystal display device of Figure 6, taken from a 45 position. Extreme 60. The state in which the polarized state of the transmitted light changes as it passes through the respective members when viewed obliquely is projected on the s丨·s 2 plane of the Poincare sphere. Figure 11 is a perspective exploded view showing the configuration of a circularly polarized VA mode liquid crystal display device including second and third birefringent layers. Figure 12 is a view of the circularly polarized VA mode liquid crystal display device of Figure n (Nzql = Nzq2 = 2.0 > R3 = -61 nm > Rlc = 320 nm > Nz2 = -〇.3〇, R2 = 118 nm) 'The state in which the polarized state of the transmitted light changes as it passes through the respective members when viewed from the front direction is projected on the S1-S2 plane of the Poincare sphere. Fig. 13 is for the graph (Nzql = Nzq2 = 2.0 > R3 = -61 nm > Rlc = 320 nm > ΝζΙ - οΓο^ R2 = l18 nm), and the self-orientation is 45. Very extreme. Observed obliquely

The state in which the polarized state of the transmitted light changes as it passes through the respective members is shown in the S1-S2 plane of the Magic Calais ball. X Figure 14 is a pattern of liquid crystal display for the circular polarized light of Figure U (Nzql = Nzq2 = 2.0 ' R3 = -61 nm ' Rlc = 320 nm ' z 2 ~ . 3 〇, R2 = 118 nm), from Azimuth. Very extreme. <The state of polarization of transmitted light when viewed obliquely is reflected in the S1-S2 plane of the Poincare sphere whenever it passes through each member. Figure 15 is a graph showing the average Nzq of the Nz coefficients of the first and second λ/4 plates and the Nz coefficient of the second birefringent layer for the circularly polarized VA mode liquid crystal display of Figure 11; 163390.doc • 86 - 201243449 A chart of the relationship between the best values of Nz2. 16 is a view showing the optimum value of the average value Nzq of the Nz coefficients of the first and second λ/4 plates and the in-plane retardation R2 of the second birefringent layer for the circularly polarized VA mode liquid crystal display device of FIG. Relationship chart. Fig. 17 is a graph showing the relationship between the average value Nzq of the Nz coefficients of the first and second λ/4 plates and the optimum value of the Nz coefficient Nz2 of the first and second second birefringent layers. Fig. 18 is a graph showing the relationship between the average value Nzq of the Nz coefficients of the first and second λ/4 plates and the optimum value of the in-plane phase difference R2 of the first and second second birefringent layers. Figure 19 is a graph showing the average Nzq of the Nz coefficients of the first and second λ/4 plates when using the second birefringent layer of Nz2 = 0 in the range of Nzq < 2.00 and the first and second second A graph showing the relationship between the optimum values of the in-plane retardation R2 of the birefringent layer. Figure 20 is a perspective exploded view showing the configuration of a circularly polarized VA mode liquid crystal display device including a second birefringent layer and not including a third birefringent layer. Fig. 2 is a schematic view showing an example of a region formed in the liquid crystal cell of the first embodiment. Fig. 22 is a schematic view showing an example of a region formed in the liquid crystal cell of the first embodiment. Fig. 23 is a schematic view showing an example of a region formed in the liquid crystal cell of the first embodiment. Figure 24 is a perspective exploded view showing the configuration of a liquid crystal display device of a circularly polarized VA mode 163390.doc -87 - 201243449 comprising two second birefringent layers. Figure 25 is a perspective exploded view showing the configuration of a circularly polarized VA mode liquid crystal display device including a second birefringent layer. Figure 26 is a perspective exploded view showing the configuration of a circularly polarized VA mode liquid crystal display device including two second birefringent layers. Fig. 27 is a graph showing the gamma curve obtained by measuring the liquid crystal display device of Example 1. Fig. 28 is a graph showing the gamma curve obtained by measuring the liquid crystal display device of Example 2. Fig. 2 is a graph showing the gamma curve obtained by not measuring the liquid crystal display device of Example 3. Fig. 30 is a graph showing the gamma curve obtained by measuring the liquid crystal display device of Example 4. Fig. 3 is a graph showing the gamma curve obtained by measuring the liquid crystal display device of Example 5. Fig. 32 is a graph showing the gamma curve obtained by measuring the liquid crystal display device of Example 6. Figure 33 is a graph showing the gamma curve obtained by measuring the liquid crystal display device of Example 7. Fig. 34 is a graph showing the gamma curve obtained by measuring the liquid crystal display device of Comparative Example 1. Fig. 35 is a graph showing the gamma curve obtained by measuring the liquid crystal display device of Comparative Example 2. Fig. 36 is a graph showing the gamma 163390.doc -88 - 201243449 curve obtained by measuring the liquid crystal display device of Comparative Example 3. 37(a) is an enlarged schematic view showing a cross section of a moth eye film, and a description of a change in refractive index at an interface between a moth eye film and an air layer. FIG. 38 is a view showing a circularly polarized VA mode liquid crystal display with a moth eye. An exploded view of the composition of the membrane. [Explanation of main component symbols] (b) is a diagram. Attached to the device

100 circularly polarized VA mode liquid crystal display device 110 First polarizing element 111 Absorbing axis 120 of the first polarizing element First λ/4 plate 121 Delay axis of the first λ/4 plate 130 VA mode liquid crystal cell 140 Second λ/4 Plate 141 second λ/4 plate slow phase axis 150 second polarizing element 151 second polarizing element absorption axis 200 circularly polarized VA mode liquid crystal display device 210 first polarizing element 220 first λ/4 plate 230 VA mode liquid crystal cell 235 third birefringent layer 240 second λ/4 plate 250 second polarizing element 300 circularly polarized VA mode liquid crystal_display device 163390.doc -89- 201243449 310 first polarizing element 315 second birefringent layer 320 first λ/4 plate 330 VA mode liquid crystal cell 335 third birefringent layer 340 second λ/4 plate 350 second polarizing element 360 moth eye film 361 protrusion 362 film base portion 400 circularly polarized VA mode liquid crystal display device 410 first Polarizing element 415 Second birefringent layer 420 First λ/4 plate 430 VA mode liquid crystal cell 440 Second λ/4 plate 450 Second polarizing element 500 Circularly polarized VA mode liquid crystal display device 510 First polarizing element 515 A second birefringent layer 520 of the first λ / 4 plate 530 VA LC cell 535 birefringent layer 540 of the second λ / 4 plate 163390.doc -90- 201243449

545 550 600 610 620 630 640 645 650 700 710 715 720 730 735 740 745 750 D1 D2 D3 D4 Second second birefringent layer second polarizing element circularly polarized VA mode liquid crystal display device first polarizing element first λ / 4-plate VA mode liquid crystal cell second λ/4 plate second birefringent layer second polarizing element circularly polarized VA mode liquid crystal display device first polarizing element first second birefringent layer first λ/4 plate VA mode Liquid crystal cell, third birefringent layer, second λ/4 plate, second second birefringent layer, second polarizing element, liquid crystal molecules, 22.5° azimuth, oblique alignment, liquid crystal molecules, 112.5° azimuth, oblique alignment, liquid crystal molecules 202.5° azimuth oblique alignment of the liquid crystal molecules in the 292.5° azimuth tilt alignment area 163390.doc -91-

Claims (1)

201243449 VII. Patent application scope: 1. A liquid crystal display device, which is defined as a first birefringent layer when the birefringent layer satisfying the relationship of nx>ny^nz is sequentially provided: a first polarizing element; a λ/4 plate whose in-plane phase difference is adjusted to λ/4; a liquid crystal cell comprising a pair of substrates facing each other and a liquid crystal layer sandwiched between the pair of substrates; a second λ/4 plate, It has a different coefficient than the first λ/4 plate, and the in-plane phase difference is adjusted to χ/4; and the second polarizing element; and the first and first λ/4 plates are the first birefringent layer The orientation of the absorption axis of the second polarizing element is defined as 〇. The in-plane slow axis of the second λ/4 plate is approximately 45. From the angle, the in-plane slow axis of the first λ/4 plate is approximately 135. The angle of the absorption of the first polarizing element is approximately 9 〇. In the liquid crystal display device, the display luminance is changed by changing the state in which the liquid crystal molecules in the liquid crystal layer are substantially perpendicularly aligned with respect to the substrate surface to the oblique alignment state, and the liquid crystal layer has liquid crystal molecules at 12.5. ~32.5. The area of the azimuth oblique alignment and the liquid crystal molecules are at 102.5. ~122.5. The area of the azimuth oblique alignment and the liquid crystal molecules are at 192.5. ~212.5. The region of the azimuth oblique alignment and the liquid crystal molecules are at 282_5. ~302.5° azimuth tilted alignment area. 2. The liquid crystal display device of claim 1, wherein 163390.doc 201243449 one of the first λ/4 plate and the second λ/4 plate has an Nz coefficient of 2 or more; the first λ/4 plate and The other of the second λ/4 plates has an Nz coefficient of 1 or more and less than 2. 3. The liquid crystal display device of claim 1 or 2, wherein the first and second λ/4 plates have a larger Nz coefficient disposed on a back side of the liquid crystal cell. 4. The liquid crystal display device of any one of claims 1 to 3, wherein the Nz coefficient of the first λ/4 plate is greater than the Nz coefficient of the second λ/4 plate; and the observation surface side of the second polarizing element Furthermore, it has a surface treatment layer. 5. The liquid crystal display device of any one of claims 1 to 4, wherein the birefringent layer satisfying the relationship of nx <ny$nz is defined as the second birefringent layer, the first λ/4 plate A second birefringent layer is further provided between the first polarizing element and the in-plane axis of the second birefringent layer is substantially orthogonal to the absorption axis of the first polarizing element. 6. The liquid crystal display device of claim 5, wherein the second birefringent layer is disposed on a back side of the liquid crystal cell. 7. The liquid crystal display device of claim 6, wherein the Nz coefficient of the first λ/4 plate is greater than the Nz 163390.doc 201243449 number of the second λ/4 plate; the second birefringent layer and the first The λ/4 plate is disposed on the back side of the liquid crystal cell. 8. The liquid crystal display device according to any one of claims 5 to 7, wherein when the birefringent layer satisfying the relationship of ηχ and ny2nz is defined as the third double-refractive layer, the first λ/4 plate is At least one of the liquid crystal cells and between the liquid crystal cell and the second λ/4 plate further includes at least one third birefringent layer. The liquid crystal display device of claim 8, wherein the at least one layer of the third birefringent layer is disposed on a back side of the liquid crystal cell. 10. The liquid crystal display device of claim 8, wherein the first λ/4 plate has a Νζ coefficient greater than a Νζ coefficient of the second λ/4 plate; Q the second birefringent layer, the first λ/4 plate And the at least one layer of the third birefringent layer is disposed on the back side of the liquid crystal cell. 11. The liquid crystal display device according to any one of claims 8 to 10, wherein the average value of the Νζ coefficients of the first and second λ/4 plates is defined as Nzq, and the black color of the liquid crystal cell is displayed The phase difference in the thickness direction is defined as Rlc, and when the sum of the phase differences in the thickness direction of the at least one third birefringent layer is defined as R3, 163390.doc 201243449 satisfies the following formula (1) to (3): 1.0 <Nzq<;2.9 (1) (169 nmxNzq-81 nm)-50 nm<Rlc+R3 (2) Rlc+R3<(169 nmxNzq-81 nm)+50 nm (3) 0 12. Liquid crystal display device according to claim 11 Wherein the Nz coefficient of the second birefringent layer is defined as Nz2, and when the in-plane phase difference is defined as R2, the following formulas (4) to (7) are satisfied: (-0.63 xNzq2 + 0.56xNzq+0.40) -0.80<Nz2 (4) Nz2<(-0.63xNzq2+0.5 6xNzq+0.40)+0.80 (5) (43 nmxNzq2-226 nmxNzq+370 nm)-50 nm<R2 (6) R2<(43 nmxNzq2-226 nmxNzq+370 nm)+50 nm (7). 13. The liquid crystal display device of claim 12, wherein 1.40^Nzq is satisfied. 14. The liquid crystal display device of any one of claims 8 to 11, wherein the average of the Nz coefficients of the first and second λ/4 plates is defined as Nzq, and the Nz of the second birefringent layer is The coefficient is defined as Nz2, and when the in-plane phase difference is defined as R2, Nzq<1.40 is satisfied, -0.80$Nz2S0 is satisfied, and 88 nm$R2Sl 88 nm is satisfied. 15. The liquid crystal display device of any one of claims 5 to 7, wherein the birefringent layer satisfying the relationship of nx and ny > nz is defined as the third birefringent layer, on the first λ/4 plate A third birefringent layer is not provided between the liquid crystal cell and the liquid crystal cell and the second λ/4 plate. 163390.doc