KR100950358B1 - Liquid crystal display device - Google Patents

Abstract

The liquid crystal display device is provided on one of the outer surfaces of the liquid crystal display panel LPN comprising uniformly oriented liquid crystal molecules, the first polarizing plate 51, the first retardation plate RF1-here, a nematic liquid crystal The nematic liquid crystal molecules are solidified in a state in which the molecules are co-orientated to the liquid crystal state along the vertical direction, and the first optical element OD1 including the second retardation plate RF2 and the second polarizing plate 52. It includes the second optical element (OD2) consisting of.

Liquid crystal display, optical element, liquid crystal molecule, polarizer, retarder

Description

Liquid crystal display device {LIQUID CRYSTAL DISPLAY DEVICE}

The present invention relates generally to liquid crystal display devices, and more particularly to transmissive liquid crystal display devices having a liquid crystal layer comprising uniformly oriented liquid crystal molecules.

For vertically aligned (VA) mode liquid crystal display devices having excellent display characteristics in the front viewing direction, such as twisted nematic (TN) mode liquid crystal display devices, by using a retardation film to compensate for the viewing angle A technique for realizing a wide viewing angle characteristic has been proposed (see, for example, Japanese Patent Application No. 2005-099236).

In addition, a technique for producing a biaxial birefringence film that can be applied to a liquid crystal display device such as a super twisted nematic (STN) mode liquid crystal display device has been proposed (for example, Japanese Patent Application Publication No. 2005-181451). Reference).

In recent years, with respect to a liquid crystal display device in which a liquid crystal layer comprising uniformly oriented liquid crystal molecules is provided between a pair of substrates, for example, for improvement of display quality such as improvement of contrast and increase of viewing angle, There has been a demand. On the other hand, there has been a demand for reduction of overall device thickness and cost reduction.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and an object of the present invention is to provide a liquid crystal display device having good display quality, which can realize a reduction in thickness and cost.

According to an aspect of the present invention, there is provided a liquid crystal display panel including a liquid crystal layer including uniformly oriented liquid crystal molecules disposed between a first substrate and a second substrate facing each other; A first polarizer plate and a first retardation plate and a second retardation plate provided on one of the outer surfaces of the liquid crystal display panel and disposed between the first polarizer plate and the liquid crystal display panel. A first optical element comprising a; And a second optical element including a second polarizing plate provided on another outer surface of the liquid crystal display panel, wherein the first retardation plate adds a predetermined delay to light having a predetermined wavelength, and generates nematic liquid crystal molecules. There is provided a liquid crystal display device comprising a liquid crystal film layer in which the nematic liquid crystal molecules solidify in a state that they are hybrid-aligned along a vertical direction.

The present invention can realize a reduction in thickness and cost, and can provide a liquid crystal display device having good display quality.

Further objects and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or will be learned by practice of the invention. The objects and advantages of the invention can be realized and attained using means and combinations particularly pointed out hereinafter.

Now, a liquid crystal display device according to an embodiment of the present invention will be described with reference to the accompanying drawings. In this embodiment, a liquid crystal display device is illustrated that includes a transmissive display portion that displays an image by selectively passing a backlight.

As shown in Figs. 1 and 2, the liquid crystal display device is an active-matrix-type color liquid crystal device including a transmissive liquid crystal display panel (LPN). The liquid crystal display panel LPN includes an array substrate (first substrate) AR, a counter substrate (second substrate) CT disposed opposite to the array substrate AR, and the array substrate AR and the counter substrate CT. It is comprised so that the liquid crystal layer LQ provided in between may be included.

In addition, the liquid crystal display device may include a first surface provided on one of the outer surfaces of the liquid crystal display panel LPN (that is, the other outer surface opposite to one outer surface of the array substrate AR facing the liquid crystal layer LQ). Second optical provided on the optical element OD1 and the other outer surface of the liquid crystal display panel LPN (that is, the other outer surface opposite to the one outer surface of the counter substrate CT facing the liquid crystal layer LQ). The element OD2 is included. The liquid crystal display device also includes a backlight unit BL that illuminates the liquid crystal display panel LPN from the first optical element OD1 side.

The liquid crystal display panel LPN includes a plurality of display areas DSP for displaying an image. The display area DSP is composed of a plurality of pixels PX arranged in an m × n matrix.

The array substrate AR is formed using an insulating substrate 10, such as a glass substrate or a quartz substrate, having light transmittance. In detail, the array substrate AR is disposed in the display area DSP in the row direction of the (m X n) pixel electrodes EP and the pixel electrodes EP disposed in the respective pixels. N scanning lines (Y, Y1 to Yn) formed, m signal lines (X, X1 to Xm) formed in the column direction of the pixel electrodes (EP), and respective pixels PX (M X n) switching elements (W) disposed in regions including intersections between scan lines (Y) and signal lines (X) in.

Further, in the driving circuit region DCT near the display region DSP, the array substrate AR is at least a portion of the scan line driver YD connected to the n scan lines Y, and the m signal lines. At least a portion of the signal line driver XD coupled to (X). The scan line driver YD continuously supplies the scan signals (drive signals) to the n scan lines Y under control by the controller CNT. The signal line driver XD, under the control of the controller CNT, performs video signals (drive signals) on the m signal lines X at a timing at which the switching elements W of each row are turned on by the scan signal. Supplies). Accordingly, the pixel electrodes EP in each row are set to pixel potentials corresponding to the video signals supplied through the associated switching elements W. FIG.

Each of the switching elements W is, for example, an n-channel thin film transistor and includes a semiconductor layer 12 disposed on the insulating substrate 10. The semiconductor layer 12 may be formed using, for example, polysilicon or amorphous silicon. In this embodiment, the semiconductor layer 12 is formed of polysilicon. The semiconductor layer 12 includes a source region 12S and a drain region 12D into which the channel region 12C is inserted. The semiconductor layer 12 is covered with the gate insulating film 14.

The gate electrode WG of the switching element W is connected to (or integrally formed with) the scan line Y. The gate electrode WG and the scan line Y are disposed on the gate insulating film 14. The gate electrode WG and the scan line Y are covered with the interlayer insulating film 16.

The drain electrode WD and the source electrode WS of the switching element W are disposed on the interlayer insulating film 16 on both sides of the gate electrode WG. The source electrode WS is connected to one associated signal line X (or integrally formed with the signal line X) and disposed in contact with the source region 12S of the semiconductor layer 12. The drain electrode WD is connected to one associated pixel electrode EP (or integrally formed with the pixel electrode EP) and disposed in contact with the drain region 12D of the semiconductor layer 12. The source electrode WS, the drain electrode WD, and the signal line X are covered with the organic insulating film 18.

The pixel electrode EP is disposed on the organic insulating layer 18 and is electrically connected to the drain electrode WD through a contact hole formed in the organic insulating layer 18. The pixel electrode EP is formed of a light transmissive conductive material such as indium tin oxide (ITO). The pixel electrode EP disposed in each associated pixel PX is covered with an alignment film 20.

On the other hand, the counter substrate CT is formed using a light transmissive insulating substrate 30 such as a glass substrate or a quartz substrate. In detail, the counter substrate CT includes a counter electrode ET in the display area DSP. The counter electrode ET is disposed to face the pixel electrodes EP associated with the plurality of pixels PX. The counter electrode ET is formed of a light transmissive conductive material such as ITO. The counter electrode ET is covered with the alignment layer 36.

The liquid crystal display device of the color display type includes a color filter layer 34 provided on the inner surface of the liquid crystal display panel LPN in association with each pixel. In the example shown in FIG. 2, the color filter layer 34 is provided on the counter substrate CT. The color filter layer 34 is formed of color resins of a plurality of colors, for example, three primary colors of red, blue, and green. A red color resin, a blue color resin, and a green color resin are disposed in association with the red pixel, the blue pixel, and the green pixel, respectively. The color filter layer 34 may be disposed on the array substrate AR side.

Each pixel PX is divided by a black matrix (not shown). The black matrix is disposed opposite the wirings such as the scan lines Y, the signal lines X, and the switching elements W provided on the array substrate AR.

When the counter substrate CT and the above-described array substrate AR are disposed to face each other alignment layers 20 and 36, spacers (not shown) that are disposed between the alignment layers 20 and 36 (eg, Predetermined spacing is provided by columnar spacers formed of resin material. The liquid crystal layer LQ is composed of a liquid crystal composition including liquid crystal molecules 40, which are sealed within a gap between the alignment layer 20 of the array substrate AR and the alignment layer 36 of the counter substrate CT. In the present embodiment, the liquid crystal layer LQ includes liquid crystal molecules 40 having a twist angle of 0 degrees (uniform orientation).

In the liquid crystal display device according to the embodiment of the present invention, as shown in FIG. 3, the first optical element OD1 and the second optical element OD2 control the polarization state of light passing therethrough. In detail, the first optical element OD1 has a polarization state of light passing through the first optical element OD1 so that light can be incident on the liquid crystal layer LQ in a polarization state of elliptical polarization as close to linear polarization as possible. To control. Therefore, while the backlight passes through the first optical element OD1, the polarization state of the backlight incident on the first optical element OD1 is changed to a predetermined polarization state. Then, the backlight exiting from the first optical element OD1 enters the liquid crystal layer LQ while maintaining a predetermined polarization state. When a voltage for black display (black display voltage) is applied to the liquid crystal layer LQ, the polarization state of light incident on the liquid crystal display panel LPN is affected by the phase difference of the liquid crystal layer LQ, and substantially Change to a linearly polarized state.

The second optical element OD2 passes through the second optical element OD2 so that light can be incident on the liquid crystal layer LQ in a polarization state of linearly polarized light (or an elliptical polarization state as close to linearly polarized light as possible). Control the polarization state of light. Therefore, while the light passes through the second optical element OD2, the polarization state of the light incident on the second optical element OD2 is changed into a predetermined polarization state, that is, a linear polarization state.

In other words, the polarization state of the light passing through the first optical element OD1 and the liquid crystal display panel LPN is substantially equal to the ellipticity of the light passing through the second optical element OD2 (= shortening). It is a substantially linear polarized light with directional amplitude Es / long axis amplitude Ep). Here, the substantially linear polarized light is a polarized state having an ellipticity of 0.1 or less, preferably 0.02 or less. By using this structure, the contrast in the vertical direction of the liquid crystal display panel LPN can be improved, and the viewing angle can be increased.

Each structural component will now be described in more detail.

The first optical element OD1 may include a first polarizer plate 51, a first retardation plate RF1 and a first disposed between the first polarizer 51 and the liquid crystal display panel LPN. 2 delay plate (RF2). In the example shown in FIG. 3, the first retardation plate RF1 is disposed between the first polarizing plate 51 and the liquid crystal display panel LPN (array substrate AR). The second retardation plate RF2 is disposed between the first polarizing plate 51 and the first retardation plate RF1.

The second optical element OD2 is formed of the second polarizing plate 52.

Each of the first and second polarizing plates 51 and 52 used in the present embodiment has an absorption axis and a transmission axis perpendicular to each other in a plane perpendicular to the traveling direction of light. Each of the polarizers extracts light having vibration surfaces in arbitrary directions, light having vibration surfaces in a direction parallel to the transmission axis, that is, light having a linear polarization state.

The first retardation plate RF1 used herein is a retardation plate having optical anisotropy. As shown in FIG. 4A, the first retardation plate RF1 includes a liquid crystal film layer 60, where nematic liquid crystal molecules 60 have optically positive uniaxial refractive index anisotropy. In this liquid crystal phase, it coagulates in a hybrid-aligned state along the vertical direction (ie, the thickness direction of the retardation plate).

For example, in the liquid crystal film layer 60 near the interface on the array substrate AR side, the liquid crystal molecules 61A are oriented at a relatively large inclination angle with respect to the interface (that is, the liquid crystal molecules 61A are substantially Oriented perpendicular to the interface). On the other hand, in the vicinity of the boundary surface on the second retardation plate RF2, the liquid crystal molecules 61B are oriented at a relatively small inclination angle with respect to the boundary surface (ie, the liquid crystal molecules 61B are substantially aligned parallel to the boundary surface). do). In summary, in the liquid crystal display panel LPN, the alignment direction of the liquid crystal molecules on the array substrate AR side when voltage is applied differs by 180 degrees from the compound direction of the liquid crystal molecules included in the first retardation plate RF1. NH film (manufactured by Nippon Oil Corporation) can be used as the first retardation plate (RF1). The liquid crystal film has a function of optically compensating for the delay of the liquid crystal layer LQ, which varies with the viewing angle due to the alignment of the liquid crystal molecules 40 included in the liquid crystal layer LQ, which increases the viewing angle. Corresponds to the delay plate having the function of

With respect to the liquid crystal layer LQ in which the orientation of the liquid crystal molecules 40 having refractive index anisotropy changes with the applied voltage and the retardation plate having refractive index anisotropy, when the birefringence is discussed, the slow axis has a relatively low refractive index. The fast axis corresponds to the axis where the refractive index is relatively small. It is assumed that the slow axis coincides with the oscillating plane of extraordinary rays and the fast axis coincides with the oscillating plane of normal rays. If the refractive indices of the normal light rays and the refractive indices of the abnormal light rays are no and ne, respectively, and the thickness of the liquid crystal layer LQ extended in the traveling direction of the light rays is d, the delay of the liquid crystal layer LQ is Δn · d (nm) = ( ne · d − no ·) (ie, Δn = ne−no). In addition, with respect to the retardation plate, main refractive indices corresponding to three mutually perpendicular axes are used. If the major refractive indices corresponding to the axes perpendicular to each other in the plane of the retardation plate are nx and ny, and the main refractive index corresponding to the axis in the vertical direction (ie, the thickness direction of the retardation plate) is nz and the thickness of the retardation plate is d, , The frontal delay of the delay plate is defined as R = (nx-ny) .d.

Each of the first retardation plate RF1 and the second retardation plate RF2 included in the first optical element OD1 has a slow axis and a fast axis perpendicular to each other, and have a predetermined frontal delay.

In detail, the first retardation plate RF1 has, in addition to the above-described viewing angle increasing function, a predetermined wavelength passing through a slow axis that is a director of the liquid crystal molecules 61 and a fast axis that is perpendicular to the slow axis. For example, it has the function of a delay plate adding a predetermined delay (i.e., lambda / m delay, where lambda is a wavelength and m is a positive number) between the light components of 550 nm.

Further, the second retardation plate RF2 has a predetermined delay (i.e., lambda / n delay, where lambda is a wavelength, n) between light components of a predetermined wavelength (e.g., 550 nm) passing through the fast axis and the slow axis. Is positive). ZEONOR (made by OPTES) and ARTON (made by JSR) can be used for the second retardation plate.

In the first optical element OD1, each of the structural components may include an absorption axis A1 of the first polarizing plate 51, an in-plane slow axis D1 of the first retardation plate RF1, And the in-plane slow axis D2 of the second retardation plate RF2 are arranged to have a predetermined angle relationship. In detail, the second retardation plate RF2 includes the first polarizing plate 51 such that the slow axis D2 of the second retardation plate RF2 is about 45 ° with respect to the absorption axis A1 of the first polarizing plate 51. ) Is disposed on. The first retardation plate RF1 includes the second retardation plate RF2 such that the slow axis D1 of the first retardation plate RF1 is about 90 ° with respect to the slow axis D2 of the second retardation plate RF2. Is disposed on. When the first optical element OD1 is disposed on the liquid crystal display panel LPN, the slow axis D1 of the first retardation plate RF1 having the viewing angle increasing function is the liquid crystal layer of the first optical element OD1. Liquid crystal molecules in the first retardation plate RF1 substantially parallel to the director of the liquid crystal molecules 40 of the LQ (the rubbing direction of the alignment layer 20 on the array substrate AR side). The hybrid-alignment direction of 61 is arranged to be opposite to the rubbing direction of the alignment film 20 on the array substrate AR side.

In the second optical element OD2, the second polarizing plate 52 is disposed such that its absorption axis A2 is perpendicular to the absorption axis A1 of the first polarizing plate 51 (about 90 °).

By such a structure, the first optical element OD1 has a function of converting the elliptically polarized light into light having a predetermined ellipticity or substantially linearly polarized light and increasing a viewing angle. In addition, the second optical element OD2 has a function of converting substantially linearly polarized light into an ellipticity substantially equal to an ellipticity of light passing through the first optical element OD1 and the liquid crystal display panel LPN. .

In particular, the birefringent material forming the retardation plate has a property that the main refractive index of the birefringent material depends on the wavelength of light. Thus, the delay R of the retardation plate depends on the wavelength of light passing through. Therefore, as described above, by using the first optical element OD1 to which at least two kinds of retardation plates are combined, the wavelength dependency of the delay R can be alleviated, and the range of all wavelengths used for the color display. At some delay may be added, and the desired polarization state may be obtained.

In detail, the backlight emitted from the first optical element OD1 is converted into light that is substantially linearly polarized and is incident on the liquid crystal layer LQ. It is assumed that the long axis direction of the light that is substantially linearly polarized is parallel to the X axis. In the liquid crystal layer LQ, when no voltage is applied (or when a low voltage is applied), a λ / 2 delay is added to the substantially linearly polarized light entering the liquid crystal layer LQ. Accordingly, the light emitted from the liquid crystal layer LQ is converted into linearly polarized light perpendicular to the substantially linearly polarized light entering the liquid crystal layer. In short, the oscillating plane of this linearly polarized light is parallel to the Y axis perpendicular to the X axis. Therefore, by using the second polarizing plate 52 having the absorption axis parallel to the X axis for the second optical element OD2, the linearly polarized light emitted from the liquid crystal layer LQ is high without using another retardation plate. Can pass through ("white display").

On the other hand, in the liquid crystal layer LQ, when a voltage is applied (or when a high voltage is applied), a delay that is substantially zero (zero) with respect to the substantially linearly polarized light incident on the liquid crystal layer LQ. Is added. Accordingly, the light emitted from the liquid crystal layer LQ maintains the same polarization state as that of the substantially linearly polarized light still entering the liquid crystal layer. In short, the oscillating plane of this linearly polarized light is parallel to the X axis. Therefore, by using the second polarizing plate 52 having the absorption axis parallel to the X axis for the second optical element OD2, the linearly polarized light emitted from the liquid crystal layer LQ is high without using another retardation plate. Absorption rate (“black display”) can be absorbed. As described above, since the second optical element is composed of only the second polarizing plate 52 without using the retardation plate, reduction in thickness and cost can be realized, and good optical characteristics can be obtained.

Next, with respect to a method for obtaining better optical properties, in particular with respect to optical compensation in black display, the frontal delay R (RF1) of the first retardation plate RF1 in the first optical element OD1. And a relationship between the front delay R (RF2) of the second retardation plate RF2 and the residual delay R (LQ) of the liquid crystal layer LQ in the black display.

Now, the residual delay R (LQ) of the liquid crystal layer LQ is described. When a voltage for a black display (“black display voltage”) is applied to the liquid crystal layer LQ, the liquid crystal molecules 40 located at an intermediate portion (“intermediate plane”) away from the interface of the substrate have an electric field in the long axis direction. Oriented to be substantially parallel to the direction. Therefore, the frontal delay of the intermediate surface of the liquid crystal layer LQ is considered to be substantially 0 nm. However, liquid crystal molecules 40 oriented near the interface of the substrate are affected by the orientation restricting force (“anchoring”) of the interface, and the liquid crystal molecules 40 have low response to voltage. Has a substantially initial orientation state. Therefore, the frontal delay around the boundary surface of the substrate of the liquid crystal layer LQ does not become 0 nm. As a result, even if a sufficiently high black display voltage is applied to the liquid crystal layer LQ to achieve a black display, a front delay remains in the liquid crystal layer LQ due to the effect of anchoring at the interface of the substrate. This is commonly referred to as "residual retardation".

In this embodiment, (1) each of the liquid crystal layers LQ, the first retardation plate RF1, and the second retardation plate RF2 used have a positive retardation rate, and (2) the liquid crystal layer ( The director of the liquid crystal molecules 40 in the LQ is set substantially parallel to the slow axis D1 of the first retardation plate RF1, and (3) the slow axis D1 of the first retardation plate RF1. Is set to about 90 ° with respect to the slow axis D2 of the second retardation plate RF2. Therefore, the front delay R (RF1) of the first retardation plate RF1 of the first optical element OD1 and the front delay R (RF2) of the second retardation plate RF2 and the liquid crystal layer LQ The total delay R (total) of the residual delay R (LQ) is expressed as R (total) = R (LQ) + R (RF1)-R (RF2).

In the above equation, each delay is set such that R (total) is zero, that is, R (LQ) + R (RF1) = R (RF2). Accordingly, optical compensation between the first optical element OD1 and the liquid crystal layer LQ may be realized. In detail, in the present embodiment, the polarization state of the backlight is not converted into substantially linear polarization only by the first optical element OD1 alone. In consideration of the residual delay of the liquid crystal layer LQ, the polarization state of the light emitted from the liquid crystal display panel LPN is converted into a substantially linear polarization (ellipticity <0.1).

More specifically, the sum of the residual delay of the liquid crystal layer LQ and the front delay of the first retardation plate RF1 is set to be substantially the same as the front delay of the second retardation plate RF2. Accordingly, in the black display, after the backlight passes through the first optical element OD1 and the liquid crystal layer LQ, the backlight from the backlight unit BL can be converted into light in a polarization state as close to linear polarization as possible. have. Therefore, in the case of the black display as well as the above-described white display, the polarization state of the light emitted from the first optical element OD1 and the liquid crystal layer LQ can be close to linear polarization having an ellipticity of substantially zero. Therefore, good optical characteristics can be obtained by simply using the second polarizing plate 52 for the second optical element OD2.

Next, the arrangement of the first optical element OD1 and the second optical element OD2 on the liquid crystal display panel LPN is discussed.

Detailed description is made with reference to FIG. 4B in which a liquid crystal display device is observed from the counter substrate CT side. For convenience, the X and Y axes that are perpendicular to each other are defined in a plane parallel to the major surface of the array substrate AR (or counter substrate CT), and the perpendicular direction to this plane is defined as the Z axis. do. The phrase "in plane" means "in plane defined by the X and Y axes". For example, the X axis corresponds to the horizontal direction of the screen, and the Y axis corresponds to the longitudinal direction of the screen. It is assumed that the direction (0 ° azimuth) on the positive side of the X axis corresponds to the right side of the screen, and the direction (180 ° azimuth) on the negative side of the X axis corresponds to the left side of the screen. In addition, the direction (90 ° azimuth) on the positive (+) side of the Y axis corresponds to the upper side of the screen, and the direction (270 ° azimuth) on the negative (-) side of the Y axis corresponds to the lower side of the screen.

In the liquid crystal display panel LPN, the rubbing direction of the alignment film 20 on the array substrate AR side is set to 45 ° with respect to the X axis.

The arrangement of the first optical element OD1 on the liquid crystal display panel LPN is set based on the rubbing direction of the alignment film 20. In detail, the 1st retardation plate RF1 is arrange | positioned so that the slow axis D1 may be orientated at the azimuth angle of 45 degrees-225 degrees parallel to the rubbing direction of the oriented film 20. FIG. In this case, the complex direction of the liquid crystal molecules included in the first retardation plate RF1 is 225 ° in the opposite direction to the rubbing direction of the alignment layer 20. The slow axis D2 of the second retardation plate RF2 is disposed substantially perpendicular to the slow axis of the first retardation plate RF1 (ie, 135 ° azimuth). Further, the first polarizing plate 51 has an absorption axis A1 of about 45 ° with respect to the slow axis D1 of the first retardation plate RF1 and the slow axis D2 of the second retardation plate RF2, eg, For example, they are arranged to be at 90 ° -270 ° azimuth.

On the other hand, the arrangement of the second optical element OD2 on the liquid crystal display panel LPN is, for example, in the azimuth direction of the light that is substantially linearly polarized from the liquid crystal layer LQ during the black display (in this case, the X axis (Azimuth direction parallel to). In detail, in the second optical element OD2, the second polarizing plate 52 has a polarization state (substantially linear) of the absorption axis A2 of the light emitted from the first optical element OD1 and the liquid crystal layer LQ. Polarization) is arranged to be substantially parallel to the major axis direction of the ellipsoid. In summary, the second polarizing plate 52 may be arranged such that its absorption axis A2 is at 0 ° -180 ° azimuth.

FIG. 5 shows the polarization state of the backlight emitted from the first optical element OD1 having the above-described structure and the liquid crystal layer LQ when a black display voltage (for example, 4.8 V) is applied to the liquid crystal layer LQ. . In the black display state, the polarization state of the light emitted from the first optical element OD1 and the liquid crystal layer LQ has a minimum possible amplitude Es compared to the amplitude Ep in the long axis direction. The ellipticity of the polarized light was about 0.017. It is also understood that the long axis direction of the substantially linearly polarized light is about 0 ° azimuth (X axis). From this, it can be seen that in order to display a high quality black image, the absorption axis A2 of the second polarizing plate 52 should preferably be set at 0 ° azimuth.

(Yes)

Next, an example of the liquid crystal display device according to this embodiment is described. The liquid crystal display device is designed in the following manner, for example.

In the liquid crystal display panel LPN, the liquid crystal layer LQ is composed of a liquid crystal composition including liquid crystal molecules that are uniformly oriented. MJ041113 (Δn = 0.065 manufactured by Merck) was used as the liquid crystal composition. At this time, the director (long-axis direction of the liquid crystal molecules) of the liquid crystal molecules 40 was limited by the rubbing direction of the alignment film 20 on the array substrate AR side, and was set to about 45 ° with respect to the X axis. The space | interval in liquid crystal layer LQ was set to 4.9 micrometers. In order to realize a black display, the voltage to be applied to the liquid crystal layer LQ was set to 4.8 V, and the residual delay of the liquid crystal layer LQ at this time was 60 nm.

First, in order to compensate for birefringence due to the liquid crystal molecules 40, the slow axis D1 of the first retardation plate RF1 of the first optical element OD1 disposed on the outer surface of the array substrate AR. That is, the alignment direction of the liquid crystal molecules 61 of the first retardation plate RF1 is set to an azimuth direction (for example, a 225 ° azimuth angle) substantially opposite to the rubbing direction of the array substrate AR, so that the relation of compensation Will be established. The frontal delay of the first retardation plate RF1 was set to 100 nm, for example.

Subsequently, the slow axis D2 of the second retardation plate RF2 is substantially perpendicular to the liquid crystal molecules 40 and the slow axis D1 of the first retardation plate RF1 (eg, 135 ° azimuth). Is set to). The front delay of the second delay plate RF2 is set to, for example, 160 nm, which corresponds to the sum of the residual delay of the liquid crystal layer LQ and the front delay of the first delay plate RF1.

Afterwards, the absorption axis A1 of the first polarizing plate 51 crosses the slow axis D1 of the first retardation plate RF1 and the slow axis D2 of the second retardation plate RF2 at about 45 °. Direction (eg, 90 ° azimuth).

On the other hand, the absorption axis A2 of the second polarizing plate 52 of the second optical element OD2 disposed on the outer surface of the counter substrate CT is substantially the absorption axis A1 of the first polarizing plate 51. Is set in the azimuth direction (eg, 0 ° azimuth) that is perpendicular to each other. As shown in Fig. 4B, the aforementioned azimuth direction with respect to the slow axis of the retardation plate and the azimuth direction with respect to the absorption axis of the polarizer are defined by angles with respect to the X axis.

The residual delay R (LQ) of the liquid crystal layer LQ, the delay R (RF1) of the first delay plate RF1, and the delay R (RF2) of the second delay plate RF2 are described above. It is not limited to values. If the values of the delays satisfy the relationship R (LQ) + R (RF1) = R (RF2), the same result is obtained in all cases.

An NH film having an average tilt angle β of 37 ° (manufactured by Nippon Oil Corporation) was used as the first retardation plate RF1. In this case, the average tilt angle β is defined as the angle of the main refractive index nz in the depth direction with respect to the vertical direction. In a simplified manner, the mean tilt angle β is defined as the value given by [(high tilt angle + low tilt angle) / 2 + low tilt angle]. For example, as shown in FIG. 4A, "high inclination angle" includes liquid crystal molecules 61A that are included in the complex-oriented liquid crystal molecules and which are raised at a maximum angle with respect to the main surface of the array substrate AR. Corresponds to the inclination angle (ie, the inclination of the array substrate with respect to the main surface). The "low inclination angle" corresponds to the inclination angle of the liquid crystal molecules 61B contained in the complex-oriented liquid crystal molecules and standing at the lowest angle with respect to the main surface of the array substrate AR.

According to this example, as shown in FIG. 6, a measurement result for viewing angle dependency of contrast ratio was obtained. In the figure showing the measurement result for the viewing angle dependency of the contrast ratio, the center corresponds to the vertical direction of the liquid crystal display panel LPN, and the concentric circles with respect to the vertical direction are inclined angles (viewing angles) of 10 ° to 80 ° with respect to the vertical direction. ) The characteristic diagram in FIG. 6 was obtained by connecting regions of isocontrast ratios in respective azimuth directions.

As shown in FIG. 6, according to the present example, it was confirmed that a sufficiently wide viewing angle of 160 ° having an iso contrast ratio (CR) = 10: 1 was obtained in both the vertical direction and the left and right directions of the screen. The contrast in the vertical direction of the screen was 400.

7A shows the structure of Comparative Example 1. FIG. The structure of the liquid crystal display panel LPN is the same as that of the above-described example. However, in Comparative Example 1, the first optical element OD1 includes a first polarizing plate, a half wavelength plate, and an NH film having an average tilt angle β of 28 degrees, and the second optical element ( OD2) includes a second polarizing plate, a half wave plate, and a quarter wave plate.

FIG. 7B shows measurement results for viewing angle dependency of contrast ratio in Comparative Example 1 having the structure shown in FIG. 7A. The viewing angle range having iso contrast ratio (CR) = 10: 1 was 140/145 ° in the vertical direction / left and right directions of the screen, respectively. The contrast in the vertical direction of the screen was 250. The measurement result of the comparative example 1 was inferior to the result of the said example.

According to the above example of the present invention, an improvement was confirmed for both the viewing angle range of the contrast and the iso contrast ratio in the vertical direction of the screen. With respect to these measurements, contrast in the vertical direction of the screen was measured by BM5-A (manufactured by TOPCON) and viewing angle characteristics by Ez-Contrast (manufactured by ELDIM).

Next, the difference between the present embodiment and Comparative Example 2 having the structure shown in Fig. 8 based on the same concept is classified, and an explanation is given to the reason why good viewing angle characteristics are obtained in this embodiment.

In this embodiment and Comparative Example 2 shown in FIG. 8, in this embodiment, the second retardation plate RF2 included in the first optical element OD1 is included in the second optical element OD2 in Comparative Example 2. Only the points are different. The present example and the comparative example 2 have the following points, that is, the liquid crystal layer (LQ); A relationship between the axial angles of the first retardation plate RF1 and the first polarizing plate 51 in the first optical element OD1; A relationship between the axial angles between the director of the liquid crystal molecules 40 included in the liquid crystal layer LQ and the first retardation plate RF1; The same is true for the front retardation R (RF1) of the first retardation plate RF1 and the average inclination angle of the first retardation plate RF1. The angle of the absorption axis A2 of the second polarizing plate 52 included in the second optical element OD2 with respect to the display panel LPN; the second retardation plate RF2 included in the second optical element OD2. Is equal for the relation between the axial angles of the front delay R (RF2) of and the slow axis D2 of the second delay plate RF2 and the slow axis D1 of the first delay plate RF1. Therefore, the TV characteristic in the frontal direction (i.e., the vertical direction of the screen) (i.e., the relationship between the transmittance of the liquid crystal layer LQ and the applied voltage) is the same between this embodiment and Comparative Example 2 shown in FIG. It is clear.

9A shows the simulation result of the viewing angle characteristic of this embodiment, and FIG. 9B shows the simulation result of the viewing angle characteristic of Comparative Example 2. FIG. From these simulation results, it can be seen that the present example and the comparative example 2 have substantially the same characteristics in the front direction, but are different in overall viewing angle characteristics. The present example has good viewing angle characteristics, but the comparative example 2 It can be seen that it has a narrower viewing angle.

To explain this result, for each structure, the polarization state of the backlight emitted from the first optical element OD1 and the liquid crystal layer LQ and the polarization of the ambient light passing through the second optical element OD2. An analysis on the matching between states was done.

Now assume that a predetermined voltage (= 4.8 V) for the black display is applied to the liquid crystal layer LQ. FIG. 10A is a characteristic diagram showing matching between two polarization states in the vertical direction of the screen in this embodiment, and FIG. 10B is a characteristic diagram showing matching between two polarization states in the vertical direction of the screen in Comparative Example 2. FIG. to be. The abscissa represents angles with respect to the vertical direction in the up and down direction of the screen, and the ordinate represents an ellipticity at 550 nm wavelength as a parameter indicating the polarization state. In the drawings, reference numeral “A” corresponds to a polarization state of a backlight emitted from the first optical element OD1 and the liquid crystal layer LQ, and reference numeral “B” denotes a polarization state of ambient light passing through the second optical element OD2. Corresponds to.

The azimuth direction of the liquid crystal molecules in the liquid crystal layer LQ is set to 45 °. 10A and 10B show the viewing angle characteristics in the vertical direction of the screen, but the same viewing angle characteristics also appear in the left and right directions of the screen. In order to realize good viewing angle compensation, it is important that the polarization state of the backlight emitted from the first optical element OD1 and the liquid crystal layer LQ substantially coincides with the polarization state of ambient light passing through the second optical element OD2. .

As is apparent from FIG. 10A, the two polarization states in this embodiment are substantially coincident. However, as shown in FIG. 10B, in Comparative Example 2, the two polarization states vary greatly as the viewing angle increases. Further, it can be seen that the front polarization state in Comparative Example 2 is an elliptical polarization having an ellipticity> 0.7, whereas the front polarization state in this embodiment is close to a substantially linear polarization having an ellipticity <0.1. In short, in the present Example and Comparative Example 2, linearly polarized light (or elliptical polarized light having a relatively small ellipticity) is mainly used in this embodiment, whereas in Comparative Example 2, circularly polarized light (or having a relatively large ellipticity) is used. Elliptical polarization) is different from each other in that it is mainly used.

When elliptical polarization having a relatively large ellipticity in the vertical direction of the screen is used as in Comparative Example 2, in most cases, it has a relationship of nx = ny> nz between the main refractive indices nx, ny, nz. A third retardation plate RF3 (negative C-plate, nC) is additionally provided to the second optical element OD2, or a negative biaxial film NB having an nx> ny <nz relationship is provided. If it is not used as the 2 retardation plate RF2, good display quality is not obtained.

FIG. 11A shows the viewing angle characteristics when the negative C-plate (manufactured by Nitto Denko) in the structure of Comparative Example 2 is disposed as the third retardation plate between the second engineering element OD2 and the liquid crystal layer LQ. . In negative C-plates, the retardation (Rth) defined as "Rth = [(nx-ny) / 2-nz] X film thickness" was set to 80 nm.

FIG. 11B illustrates a backlight emitted from the first optical element OD1 and the liquid crystal layer LQ in a structure in which a negative C-plate (Rth = 80 nm) is disposed between the second optical element OD2 and the liquid crystal layer LQ. The matching between the polarization state of and the polarization state of the ambient light passing through the second optical element (OD2). Matching between two polarization states is good, and good viewing angle characteristics can be obtained.

On the other hand, in the present embodiment, the polarization state of the backlight emitted from the first optical element OD1 and the liquid crystal layer LQ is converted into an elliptical polarization state close to substantially linearly polarized light having an ellipticity <0.1 in the front direction of the screen. Can be. Therefore, the second polarizing plate 52 alone may achieve the viewing angle compensation without using the negative C-plate (n-C) or the negative biaxial film for the second optical element OD2. Therefore, it is possible to provide a liquid crystal display device having good display quality, which can realize a reduction in thickness and cost.

The present invention is not directly limited to the above-described embodiments. In fact, structural components may be modified without departing from the spirit of the invention. By properly combining the structural components disclosed in the embodiments, various inventions can be made. For example, some structural elements may be omitted from all structural elements disclosed in the embodiments. In addition, structural elements may be combined as appropriate in different embodiments.

For example, in the above embodiment, each of the switching elements W is made of an n-channel thin film transistor. However, other structures can be constructed if various drive signals of a similar kind can be generated.

The second optical element OD2 may include a third retardation plate corresponding to the negative C-plate between the second polarizing plate 52 and the liquid crystal display panel LPN. Specifically, as shown in FIG. 12A, in the liquid crystal display device according to the modification of the present invention, the second optical element OD2 includes the second polarizing plate 52, the second polarizing plate 52, and the liquid crystal display panel ( The third delay plate RF3 is disposed between the LPNs.

The third retardation plate RF3 has refractive index anisotropy defined by the relationship nx = ny> nz, where nx and ny are refractive indices in the perpendicular directions to each other in the plane of the third retardation plate RF3, and nz is the third It is the refractive index in the vertical direction of the retardation plate RF3. In the third retardation plate RF3, the delay Rth in the vertical direction was set to 80 nm.

As shown in Fig. 12B, according to a modification having this structure, the measurement result for the viewing angle dependency of the contrast ratio in the structure of the embodiment (shown in Fig. 3) in which the third retardation plate RF3 is not provided. Compared to (shown in FIG. 6), it can be seen that almost the same viewing angle was obtained in the region having a low contrast ratio (eg, CR = 10: 1). However, in the structure of the embodiment in which the third retardation plate RF3 is not provided, it can be seen that a wider viewing angle is obtained in the region having a high contrast ratio (eg CR = 50: 1). Although not shown, even when the negative biaxial film NB is used as the third retardation plate RF3, similar characteristics as shown in FIG. 12B can be obtained.

Based on the above results, in particular, in order to increase the area of high contrast ratio, the structure of the present embodiment (ie, the structure in which the second optical element does not include both negative C-plates or negative biaxial films) is second to the second. It has been found that the optical element is more advantageous than the structure including the third retardation plate made of negative C-plate or negative biaxial film.

In the above-described embodiment, the first retardation plate RF1 is preferably made of the liquid crystal film layer 60 alone. Specifically, in the present embodiment, the first retardation plate RF1 is formed on the outer surface of the liquid crystal display panel LPN (that is, the outer surface of the insulating substrate 10 constituting the array substrate AR) and the second retardation plate. It consists of the liquid crystal film layer 60 which contacts (RF2). Like a NH film, a retardation plate having a liquid crystal film layer containing complex-oriented liquid crystal molecules performs an alignment treatment on a base film, coats a liquid crystal material on the base film, and the liquid crystal molecules It is obtained by solidifying a liquid crystal material in the state which maintains an orientation state. Triacetate cellulose (TAC) is widely used as a base film. However, the base film itself has a delay. In order to realize good optical compensation, it is required to perform compensation in consideration of the delay of the base film. Therefore, by using the NH film without the base film as in the above-described example, optical compensation can be easily realized. For reference, FIG. 13 shows measurement results obtained by measuring the viewing angle dependency of contrast ratio when the NH film with the base film is used as the first retardation plate RF1 in the same structure as in the above example.

It can be seen that a viewing angle nearly identical to the viewing angle in the structure without the base film of the example shown in FIG. 6 was obtained in a region with a low contrast ratio (eg CR = 10: 1). However, in the example of the structure without the base film, it can be seen that a wider viewing angle is obtained in the region having a high contrast ratio (eg CR = 50: 1). Based on the above results, in particular, in order to increase the area of high contrast ratio, the structure of the example (ie, the structure in which the first retardation plate RF1 is used without the base film (without TAC)) is used as the base film (TAC). It has been found that the first retardation plate RF1 having a is more advantageous than the structure used.

In the above-described embodiment, it is preferable to use the first retardation plate RF1 having the liquid crystal film layer 60 having a relatively large average inclination angle β, for example, β = 37 ° or the inclination angle close thereto. For reference, FIG. 14 shows measurement results obtained by measuring the viewing angle dependency of contrast ratio when a first retardation plate (NH film) having a liquid crystal film having β = 28 ° is applied to the same structure as in the above example. do.

It can be seen that a viewing angle nearly identical to the viewing angle in the structure with β = 37 ° in the example shown in FIG. 6 was obtained in a region with low contrast ratio (eg CR = 10: 1). However, it can be seen that in the structure of the above example with β = 37 °, a wider viewing angle is obtained in the region with a high contrast ratio (eg CR = 50: 1). Based on the above results, in particular, in order to increase the region of high contrast ratio, the average tilt angle of the structure of the above example (that is, the structure in which the first retardation plate RF1 with the liquid crystal film having a large average tilt angle) is used is small. It has been confirmed that the first retardation plate RF1 having the liquid crystal film having the structure is more advantageous than the structure used.

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and, together with the comprehensive description set forth above and the detailed description of the embodiments set forth below, serve to explain the principles of the invention. .

1 schematically shows the structure of a liquid crystal display device according to an embodiment of the present invention.

FIG. 2 schematically shows the cross-sectional structure of the liquid crystal display device shown in FIG. 1.

FIG. 3 schematically illustrates structures of the first optical element and the second optical element that may be used in the liquid crystal display device shown in FIG. 2.

4A is a diagram for explaining a relationship between the alignment of liquid crystal molecules of a liquid crystal display panel and the alignment of liquid crystal molecules of a first retardation plate when a voltage is applied.

FIG. 4B is a diagram for describing azimuth directions of slow axes of the delay plates illustrated in FIG. 3 and azimuth directions of absorption axes of polarizers.

5 is a characteristic diagram showing a polarization state after a backlight passes through the first optical element and the liquid crystal layer in the liquid crystal display device according to the present embodiment.

6 is a characteristic diagram showing a measurement result of viewing angle dependency of contrast ratio in a liquid crystal display device according to an example of this embodiment.

7A schematically shows the structure of a liquid crystal display device according to Comparative Example 1. FIG.

7B is a characteristic diagram showing a measurement result of viewing angle dependency of contrast ratio in a liquid crystal display device according to Comparative Example 1. FIG.

8 schematically shows the structure of a liquid crystal display device according to Comparative Example 2. FIG.

9A is a characteristic diagram showing a simulation result of viewing angle dependency of contrast ratio in a liquid crystal display device for the above example of this embodiment.

9B is a characteristic diagram showing a simulation result of viewing angle dependency of contrast ratio in a liquid crystal display device according to Comparative Example 2. FIG.

FIG. 10A illustrates the change in ellipticity in the vertical direction with respect to the polarization state of the backlight passing through the first optical element and the liquid crystal layer, and the vertical direction with respect to the polarization state of the ambient light passing through the second optical element. A characteristic diagram showing the matching between changes in ellipticity at.

FIG. 10B illustrates a change in ellipticity in the vertical direction with respect to the polarization state of the backlight passing through the first optical element and the liquid crystal layer in Comparative Example 2, and in the vertical direction with respect to the polarization state of the ambient light passing through the second optical element. This is a characteristic diagram showing matching between changes in ellipticity.

11A is a characteristic diagram showing a measurement result of viewing angle dependency of contrast ratio in Comparative Example 2 when a negative C-plate is disposed between the second optical element and the liquid crystal layer.

FIG. 11B is a change in ellipticity in the vertical direction with respect to the polarization state of the backlight passing through the first optical element and the liquid crystal layer in Comparative Example 2 when a negative C-plate is disposed between the second optical element and the liquid crystal layer. FIG. And a change in the ellipticity in the vertical direction to the polarization state of the ambient light passing through the second optical element.

12A schematically shows the structure of a liquid crystal display device according to a modification of the present invention in which a second optical element configured such that a third retardation plate (negative C-plate) is arranged between the second polarizing plate and the liquid crystal layer is used. .

FIG. 12B is a characteristic diagram showing a measurement result of viewing angle dependency of contrast ratio in the modification shown in FIG. 12A. FIG.

It is a characteristic view which shows the measurement result of the viewing angle dependency of contrast ratio in this Example in which NH film containing a base film is used as a 1st retardation plate.

Fig. 14 is a characteristic diagram showing a measurement result of viewing angle dependency of contrast ratio in this embodiment in which NH film having an average tilt angle of 28 degrees is used as the first retardation plate.

Claims (7)

delete As a liquid crystal display device, A liquid crystal layer including uniformly oriented liquid crystal molecules, the liquid crystal display panel being provided between a first substrate and a second substrate disposed to face each other; A first polarizer plate and a first retardation plate and a second retardation plate provided on one of the outer surfaces of the liquid crystal display panel and disposed between the first polarizer plate and the liquid crystal display panel. A first optical element comprising a; And A second optical element comprising a second polarizer provided on another outer surface of the liquid crystal display panel Including, The first retardation plate adds a predetermined retardation to light of a predetermined wavelength, and the liquid crystal film to which the nematic liquid crystal molecules solidify in a state in which nematic liquid crystal molecules are hybrid-aligned along a vertical direction. Including layers, And the first optical element controls a polarization state of light passing through the first optical element in such a manner that light having a substantially linear polarization polarization state is incident on the liquid crystal layer. As a liquid crystal display device, A liquid crystal layer including uniformly oriented liquid crystal molecules, the liquid crystal display panel being provided between a first substrate and a second substrate disposed to face each other; A first polarizer plate and a first retardation plate and a second retardation plate provided on one of the outer surfaces of the liquid crystal display panel and disposed between the first polarizer plate and the liquid crystal display panel. A first optical element comprising a; And A second optical element comprising a second polarizer provided on another outer surface of the liquid crystal display panel Including, The first retardation plate adds a predetermined retardation to light of a predetermined wavelength, and the liquid crystal film to which the nematic liquid crystal molecules solidify in a state in which nematic liquid crystal molecules are hybrid-aligned along a vertical direction. And a layer, said liquid crystal film layer in contact with said second retardation plate and said outer surface of said liquid crystal display panel. As a liquid crystal display device, A liquid crystal layer including uniformly oriented liquid crystal molecules, the liquid crystal display panel being provided between a first substrate and a second substrate disposed to face each other; A first polarizer plate and a first retardation plate and a second retardation plate provided on one of the outer surfaces of the liquid crystal display panel and disposed between the first polarizer plate and the liquid crystal display panel. A first optical element comprising a; And A second optical element comprising a second polarizer provided on another outer surface of the liquid crystal display panel Including, The first retardation plate adds a predetermined retardation to light of a predetermined wavelength, and the liquid crystal film to which the nematic liquid crystal molecules solidify in a state in which nematic liquid crystal molecules are hybrid-aligned along a vertical direction. Including layers, And the sum of the residual delay of the liquid crystal layer and the front delay of the first retardation plate is substantially equal to the front retardation of the second retardation plate. As a liquid crystal display device, A liquid crystal layer including uniformly oriented liquid crystal molecules, the liquid crystal display panel being provided between a first substrate and a second substrate disposed to face each other; A first polarizer plate and a first retardation plate and a second retardation plate provided on one of the outer surfaces of the liquid crystal display panel and disposed between the first polarizer plate and the liquid crystal display panel. A first optical element comprising a; And A second optical element comprising a second polarizer provided on another outer surface of the liquid crystal display panel Including, The first retardation plate adds a predetermined retardation to light of a predetermined wavelength, and the liquid crystal film to which the nematic liquid crystal molecules solidify in a state in which nematic liquid crystal molecules are hybrid-aligned along a vertical direction. Including layers, In the first optical element, an angle between an absorption axis of the first polarizing plate and a slow axis of the second retardation plate is set to about 45 °, and a slow axis of the first retardation plate And a director of the liquid crystal molecules included in the liquid crystal layer are set to be substantially parallel, and an angle between the slow axis of the first retardation plate and the slow axis of the second retardation plate is about 90 °. Is set to In the second optical element, an angle between an absorption axis of the second polarizing plate and an absorption axis of the first polarizing plate is set to about 90 °. As a liquid crystal display device, A liquid crystal layer including uniformly oriented liquid crystal molecules, the liquid crystal display panel being provided between a first substrate and a second substrate disposed to face each other; A first polarizer plate and a first retardation plate and a second retardation plate provided on one of the outer surfaces of the liquid crystal display panel and disposed between the first polarizer plate and the liquid crystal display panel. A first optical element comprising a; And A second optical element comprising a second polarizer provided on another outer surface of the liquid crystal display panel Including, The first retardation plate adds a predetermined retardation to light of a predetermined wavelength, and the liquid crystal film to which the nematic liquid crystal molecules solidify in a state in which nematic liquid crystal molecules are hybrid-aligned along a vertical direction. Including layers, The second optical element includes a third retardation plate between the second polarizing plate and the liquid crystal display panel, The third retardation plate has a relationship of nx = ny> nz, where nx and ny are refractive indices in directions perpendicular to each other in the plane of the third retardation plate, and nz is in the vertical direction of the third retardation plate. Refractive Index-A liquid crystal display device having refractive index anisotropy, defined as. As a liquid crystal display device, A liquid crystal layer including uniformly oriented liquid crystal molecules, the liquid crystal display panel being provided between a first substrate and a second substrate disposed to face each other; A first polarizer plate and a first retardation plate and a second retardation plate provided on one of the outer surfaces of the liquid crystal display panel and disposed between the first polarizer plate and the liquid crystal display panel. A first optical element comprising a; A second optical element including a second polarizing plate provided on another outer surface of the liquid crystal display panel; And A backlight unit illuminating the liquid crystal display panel from the first optical element side Including, The first retardation plate adds a predetermined retardation to light of a predetermined wavelength, and the liquid crystal film to which the nematic liquid crystal molecules solidify in a state in which nematic liquid crystal molecules are hybrid-aligned along a vertical direction. Liquid crystal display device comprising a layer.

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