JP2015118352A - Liquid crystal display element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a static driving TN-liquid crystal display element having a wide viewing angle and excellent in contrast.SOLUTION: A TN-liquid crystal display element 100 driven by a static driving method comprises: a liquid crystal cell 10 including a pair of substrates 11, 12, a liquid crystal layer 13, and transparent electrodes 11a, 12a; a pair of polarizers 21, 22; and viewing angle expansion films 31, 32. The liquid crystal layer 13 of the liquid crystal display element 100 is set to have a thickness (cell gap) of 2 μm or more and 3 μm or less, a retardation (Δnd) value of 0.25 μm or more and 0.5 μm or less, and a pretilt angle θp of 3° or more and 5° or less, and an On-voltage by static driving is set to be equal to or higher than twice the threshold voltage V10 of the liquid crystal layer 13.

Description

  The present invention relates to a liquid crystal display element, and more particularly to a twisted nematic type (TN type) liquid crystal display element provided with a viewing angle widening film.

  As this type of liquid crystal display element, the one disclosed in Patent Document 1 is known. The liquid crystal display element according to Patent Document 1 improves the display contrast of a TN liquid crystal display element by disposing a viewing angle widening film between a liquid crystal cell and a polarizing element.

JP-A-6-214116

  A viewing angle widening film is widely used in liquid crystal display elements including active elements such as TFT (Thin Film Transistor). In this case, a liquid crystal display element having a cell gap of about 4 μm to 6 μm is selected. Incidentally, it is naturally desirable to improve the contrast even in a static drive type liquid crystal display element. However, the methodology in the case of a liquid crystal display element having an active element cannot be directly applied to a liquid crystal display element of a static drive system. For example, if the cell gap is set within the above range, there may be a case where sufficient contrast cannot be realized.

  The present invention has been made in view of the above circumstances, and an object thereof is to provide a TN type liquid crystal display element of a static drive system having a wide viewing angle and good contrast.

In order to achieve the above object, the liquid crystal display element according to the present invention is
A liquid crystal cell having a pair of substrates facing each other, a liquid crystal layer positioned between the pair of substrates, and a transparent electrode provided on the liquid crystal layer side of each of the pair of substrates;
A pair of polarizing plates facing each other across the liquid crystal cell;
A viewing angle widening film positioned between the liquid crystal cell and at least one of the pair of polarizing plates,
A twisted nematic liquid crystal display element in which a voltage is applied to the transparent electrode by a static drive method,
The liquid crystal layer has a thickness of 2 μm or more and 3 μm or less,
The retardation value of the liquid crystal layer is 0.25 μm or more and 0.5 μm or less,
The pretilt angle of the liquid crystal layer is 3 ° or more and 5 ° or less,
ON voltage by static drive is more than twice the threshold voltage of the liquid layer,
It is characterized by that.

  According to the present invention, it is possible to provide a TN type liquid crystal display element of a static drive system with a wide viewing angle and good contrast.

(A) is a figure for demonstrating schematic structure of the liquid crystal display element which concerns on one Embodiment of this invention, (b) is an example of the display element of the liquid crystal display element which concerns on one Embodiment of this invention. FIG. It is a figure of the table | surface which shows a simulation result. It is a figure of the graph which shows the voltage-transmittance characteristic of an Example, the comparative example 1, and the comparative example 2. FIG. (A) And (b) is the figure which showed the data used as the basis of the graph of FIG.

  An embodiment of the present invention will be described with reference to the drawings.

  A liquid crystal display element 100 according to this embodiment shown in FIG. 1A is configured as a twisted nematic (TN (Twisted Nematic)) type and positive display type (normally white mode) liquid crystal display element. A predetermined display element 4 is displayed as shown in FIG.

  As shown in FIG. 1A, the liquid crystal display element 100 includes a liquid crystal cell 10, polarizing plates 21 and 22, viewing angle widening films 31 and 32, and a backlight 40.

  As shown in FIG. 1A, the liquid crystal cell 10 includes substrates 11 and 12 that are a pair of transparent substrates facing each other, and a liquid crystal layer 13. Each of the substrates 11 and 12 is made of, for example, glass, plastic, or the like, and is disposed such that the main surfaces (opposing surfaces) of the substrates 11 and 12 are parallel to each other. The substrate 11 is positioned closer to the observer 1 who visually recognizes the display element 4 than the liquid crystal layer 13.

  The substrate 11 is provided with a transparent electrode 11a and an alignment film 11b that covers the transparent electrode 11a from the liquid crystal layer 13 side. The substrate 12 is provided with a transparent electrode 12a and an alignment film 12b that covers the transparent electrode 12a from the liquid crystal layer 13 side.

  The transparent electrodes 11a and 12a are made of, for example, an ITO (Indium Tin Oxide) film containing indium oxide as a main component, and each is patterned into a predetermined shape. The transparent electrode 11a is formed on the substrate 11 and the transparent electrode 12a is formed on the substrate 12 by a known method (sputtering, vapor deposition, etching, etc.). The transparent electrode 11a is configured as a common electrode, and the transparent electrode 12a is configured as a segment electrode. Both electrodes are electrically connected to a driving IC (Integrated Circuit) 2 by a known method. The driving IC 2 is mounted on, for example, a circuit board (not shown) located on the back side (the side opposite to the observer 1) of the liquid crystal display element 100, and applies a driving voltage to both electrodes by a static driving method. The transparent electrode 11a may be configured as a segment electrode, and the transparent electrode 12a may be configured as a common electrode.

  The liquid crystal display element 100 corresponds to the shape of both electrodes in a region where the transparent electrode 11a and the transparent electrode 12a overlap in the normal direction of the opposing surfaces of the substrate 11 and the substrate 12 (hereinafter also simply referred to as the substrate normal direction). The displayed display element 4 is displayed (see FIG. 1B). The display element 4 is an element for indicating information displayed by the liquid crystal display element 100, and is composed of a symbol (including letters and numbers), a figure, or a combination thereof. As an example, as shown in FIG. 1B, the liquid crystal display element 100 can display a display element 4 such as a figure (so-called segment) representing a number by a combination and a character “km”. The liquid crystal display element 100 displays the display element 4 substantially black in the substantially white background region 3 by making light non-transparent in the region where the ON voltage is applied to the transparent electrodes 11a and 12a. In the liquid crystal display element 100, a region where the transparent electrode 11a and the transparent electrode 12a do not overlap and a region where no on-voltage is applied become the substantially white background region 3. Thus, the liquid crystal display element 100 is configured as a positive display type (normally white mode).

  Each of the alignment films 11b and 12b is a film (for example, polyimide) that is in contact with the liquid crystal layer 13, and is formed by a known method (for example, flexographic printing). The alignment film 11b is formed so as to cover the transparent electrode 11a from the liquid crystal layer 13 side, and the alignment film 12b is formed so as to cover the transparent electrode 12a from the liquid crystal layer 13 side. The alignment films 11b and 12b are rubbed, and thereby the alignment direction of liquid crystal molecules constituting the liquid crystal layer 13 is defined. The alignment process applied to the alignment films 11b and 12b is not limited to the rubbing process, but may be other known processes such as a photo-alignment process and a protrusion alignment process.

  The liquid crystal layer 13 is formed by sealing a liquid crystal material in a sealed space formed by a sealing material (not shown) that joins the substrate 11 and the substrate 12 and both substrates. The layer thickness (cell gap) of the liquid crystal layer 13 is kept constant by a spacer (not shown).

Here, the cell gap d of the liquid crystal display element 100 is set to about 4 to 6 μm, whereas the cell gap d of the liquid crystal display element 100 is an effective value of the voltage applied to the liquid crystal layer 13. In order to increase, it is set small.
Specifically, the cell gap d of the liquid crystal display element 100 is set to satisfy a condition (hereinafter referred to as condition 1) of 2 μm or more and 3 μm or less (2 μm ≦ d ≦ 3 μm). The refractive index anisotropy Δn of the liquid crystal layer 13 is set to a value between approximately 0.1 and 0.25. The liquid crystal layer 13 has a retardation Δnd, which is the product of the refractive index anisotropy Δn of the liquid crystal layer 13 and the cell gap d, of 0.25 μm to 0.5 μm (0.25 μm ≦ Δnd ≦ 0.5 μm). ) (Preferably 0.3 μm to 0.4 μm (0.3 μm ≦ Δnd ≦ 0.4 μm)) (hereinafter referred to as Condition 2).

  The liquid crystal molecules of the liquid crystal layer 13 are aligned with the alignment film 11b and the alignment film 12b that are rubbed in directions orthogonal to each other when viewed from the normal direction of the substrate. And the end on the substrate 12 side are twisted at an angle of about 90 ° and are oriented so as to rotate (turn) little by little from one substrate side to the other substrate side (chiral structure). . Thus, the liquid crystal layer 13 when no voltage is applied has chirality.

Further, in the liquid crystal layer 13, the liquid crystal molecules at positions close to the substrate 11 and the substrate 12 are arranged with an inclination with respect to the substrate surface (pretilt is given). This tilt angle is called a pretilt angle θp. In the present embodiment, the pretilt angle θp is used in order to reduce the transmittance of the display element 4 when the on-voltage is applied to the liquid crystal layer 13 and to achieve high contrast. Of 3 ° to 5 ° (3 ° ≦ θp ≦ 5 °), preferably 4 ° to 5 ° (4 ° ≦ θp ≦ 5 °) (hereinafter referred to as Condition 3). Is set.
In the conventional TN liquid crystal display element, the pretilt angle is set to about 1 to 2 degrees in order to increase the steepness. However, in the liquid crystal display element 100 according to the present embodiment, the pretilt angle is realized in order to realize high contrast. In this way, θp is set larger than the conventional one.

  Each of the polarizing plates 21 and 22 emits light incident from one surface side from the other surface side as linearly polarized light along a transmission axis orthogonal to the absorption axis. Both polarizing plates are, for example, iodine-based polarizing plates (polarizing filters). The polarizing plate 21 and the polarizing plate 22 face each other across the liquid crystal cell 10. The polarizing plate 21 is located closer to the viewer 1 than the polarizing plate 22. The polarizing plate 21 and the polarizing plate 22 are arranged so that their transmission axes are substantially orthogonal to each other (just including orthogonal) as viewed from the normal direction of the substrate (crossed Nicol arrangement). For example, as viewed from the normal direction of the substrate, the polarizing plate 21 is arranged so that its transmission axis is perpendicular to the rubbing direction applied to the alignment film 11b, and the polarizing plate 22 has its transmission axis applied to the alignment film 12b. Are arranged so as to be orthogonal to the direction of the rubbing process.

  The viewing angle widening films 31 and 32 are obtained by coating a TAC (Triacetylcellulose) film, which is also called a wide view (WV) film, with a dicotic liquid crystal layer. In addition, as the viewing angle widening films 31 and 32, known films such as those obtained by uniaxially stretching a film of polycarbonate (PC) or polyvinyl alcohol (PVA) can be used as appropriate. As will be described later, in the region where the on-voltage is applied in the liquid crystal layer 13, the liquid crystal molecules of the liquid crystal layer 13 are aligned along the voltage application direction (substrate normal direction). Liquid crystal molecules do not rise sufficiently near the interface between the substrates 11 and 12. For this reason, if no measures are taken, the display contrast may be reduced when the display surface of the liquid crystal display element 100 is viewed obliquely. The viewing angle widening films 31 and 32 prevent such problems from occurring and widen the viewing angle. The viewing angle refers to the size of the central angle (the angle formed between the substrate normal and the line of sight of the observer 1) when the range in which the display surface of the liquid crystal display element can be normally viewed from the center is represented by a fan shape. The larger the viewing angle, the more correctly the display element of the liquid crystal display element can be visually recognized (without contrast and color tone unevenness) even when viewed from an oblique direction.

  The viewing angle widening film 31 is provided between the liquid crystal cell 10 and the polarizing plate 21, and optically compensates for alignment defects when an on-voltage is applied on the substrate 11 side of the liquid crystal layer 13. For example, the viewing angle widening film 31 is attached to the surface of the polarizing plate 21 on the liquid crystal cell 10 side. The viewing angle widening film 32 is provided between the liquid crystal cell 10 and the polarizing plate 22, and optically compensates for alignment defects when an on-voltage is applied on the substrate 12 side of the liquid crystal layer 13. For example, the viewing angle widening film 32 is attached to the surface of the polarizing plate 22 on the liquid crystal cell 10 side.

  The backlight 40 is located on the back side of the polarizing plate 22 (on the side opposite to the observer 1), and illuminates the liquid crystal cell 10 by emitting light in a planar shape. The backlight 40 is composed of, for example, a light emitting diode and a light guide member. The liquid crystal display element 100 is configured as a transmissive type that performs transmissive display with the light of the backlight 40. In addition, it is also possible to provide a transflective layer such as a half mirror on the back side of the polarizing plate 22 so that the liquid crystal display element 100 is a so-called transflective type.

Here, how the liquid crystal display element 100 performs display will be briefly described.
In the liquid crystal display element 100, when no voltage is applied, the liquid crystal molecules remain substantially parallel to the substrate surface, and the liquid crystal layer 13 remains chiral. In this case, light emitted from the backlight 40 and converted into linearly polarized light by passing through the polarizing plate 22 is approximately twist angle (in this embodiment) due to the chirality of the liquid crystal layer 13 when passing through the liquid crystal layer 13. The polarization direction is inclined by 90 °). Thereby, the light that has passed through the liquid crystal layer 13 passes through the polarizing plate 21 that is arranged in a relationship of crossed Nicols with the polarizing plate 22. As a result, the background area 3 is displayed substantially white.
On the other hand, in a region where an on-voltage sufficiently higher than the threshold voltage is applied, the liquid crystal molecules of the liquid crystal layer 13 are aligned substantially along the voltage application direction (substrate normal direction), Since the chirality is lost, the polarization direction of the linearly polarized light that has passed through the polarizing plate 22 from the backlight 40 does not substantially change even when it passes through the liquid crystal layer 13. Therefore, the light that has passed through the liquid crystal layer 13 cannot pass through the polarizing plate 21. Thereby, the display element 4 is displayed in black.

  The liquid crystal display element 100 according to the present embodiment is configured to satisfy the above conditions 1 to 3. In addition, the ON voltage applied to the liquid crystal layer 13 from the driving IC 2 via the transparent electrodes 11a and 12a by the static drive method is set as high as possible, so that the liquid crystal molecules of the liquid crystal layer 13 can be changed when the ON voltage is applied. I tried to get as much display contrast as possible. Specifically, the on-voltage (effective voltage value at the time of turning on the display element 4 in the display state) is the threshold voltage V10 (the voltage at which the transmittance changes by 10% based on the transmittance when no voltage is applied). Was set to satisfy the condition of 2 times or more (hereinafter referred to as Condition 4). The conditions 1 to 4 are summarized again as follows.

Condition 1: Cell gap d is 2 μm or more and 3 μm or less Condition 2: Retardation Δnd value is 0.25 μm or more and 0.5 μm or less (preferably 0.3 μm or more and 0.4 μm or less)
Condition 3: Pretilt angle θp is 3 ° to 5 ° (preferably 4 ° to 5 °)
Condition 4: ON voltage is more than twice the threshold voltage V10

  From here, based on the simulation results shown in FIG. 2 to FIG. 4A and FIG. 4B, how the above conditions 1 to 4 are derived together with the usefulness of the liquid crystal display element 100 that satisfies these conditions. explain. This simulation result is derived by simulation software “LCD MASTER ver 8.1” manufactured by Shintech Co., Ltd.

  In this simulation, in the liquid crystal display element 100, the refractive index anisotropy of the liquid crystal layer 13 is Δn = 0.146, and the twist angle is −90 ° (90 ° twisted counterclockwise when viewed from the viewer 1 side). Then, SKN-18243T (manufactured by Polatechno Co., Ltd.) was selected as the polarizing plates 21 and 22, and the ON voltage was 5V. In addition, since this simulation mainly focuses on examining the front contrast, the viewing angle widening films 31 and 32 are not taken into consideration.

  Under the above conditions, the cell gap d is changed in the range of 1.5 μm to 6 μm and θp is appropriately changed in the range of 2 ° to 6 °, so that the transmittance when no voltage is applied (background transmission in FIG. 2). Rate), the transmittance when the on-voltage is applied (5v transmittance in FIG. 2), and the front contrast. The static drive method generally requires performance with a contrast of 150 or higher and a background transmittance of 25% or higher. In FIG. 2, those satisfying this performance are indicated as determination “◯”, those not satisfying are determined “x”, and those not satisfying are indicated as determination “Δ”.

In FIG. 2, when the cell gap d = 1.5 μm (Δnd = 0.219) and θp = 4 °, both the background transmittance and the contrast are less than the standard (determination “×”). When the cell gap is increased to d = 2 μm (Δnd = 0.292) without changing θp = 4 °, both the background transmittance and the contrast are good (determination “◯”).
As a result, even when the pretilt angle θp is 4 °, which is larger than the conventional case, if the cell gap d and the retardation Δnd are too small (the cell gap d is less than 2 μm), sufficient contrast cannot be obtained. I understand.

Next, attention is focused on the range of θp of 3 ° to 6 ° with a cell gap d = 2.5 μm (Δnd = 0.365). When θp is 4 °, 5 °, and 6 °, the background transmittance and the contrast are good (judgment “◯”), and when θp is 3 °, the contrast is “145”, which is slightly lower. The display quality is within an allowable range (judgment “Δ”). Next, focusing on the same cell gap (d = 2.5 μm) and θp of 2 °, the contrast is as low as “133” (determination “×”).
Thereby, even when the cell gap d is 2.5 μm, which is narrower (smaller) than the conventional case, if the pretilt angle θp is too small (when θp is less than 3 °), sufficient contrast can be obtained. I understand that there is not.

  Subsequently, attention is focused on the case where the cell gap d is in the range of 3 μm to 6 μm and θp is 4 °. When the cell gap d is as wide as 4 μm to 6 μm (large) as in the prior art, the contrast is low, which is not acceptable (determination “x”). When the cell gap d is 3 μm, the contrast is slightly low, “140”, but it is acceptable for the display quality (determination “Δ”).

Considering the above, in order to improve the contrast in the static drive type liquid crystal display element 100, the cell gap d should be set to 2 μm to 3 μm and the pretilt angle θp should be set to 3 ° to 5 °. I understand.
As for the retardation Δnd, the range of 0.292 to 0.438 μm is an allowable range from the table of FIG. 2, but Δn is set to a fixed value of 0.146, and as described above. Considering that a liquid crystal layer 13 having a refractive index anisotropy Δn of approximately 0.1 to 0.25 can be appropriately selected, a preferable range of the retardation Δnd is 0.25 μm or more and 0.5 μm or less. It was supposed to be. However, in order to improve the contrast, the retardation Δnd is preferably 0.3 μm or more and 0.4 μm or less.

  Further, in FIG. 2, when the cell gap d is 2.5 and θp is 6 °, the contrast is good (judgment “◯”), but when θp exceeds 5 °, the alignment of liquid crystal molecules varies. May increase, and the yield may decrease. Considering this, the range of the pretilt angle θp is set so that θp is 3 ° to 5 °, more preferably 4 ° to 5 °.

Further, in FIG. 2, in the range where the contrast is good (judgment “◯” “Δ”), the threshold voltage V10 is less than half of the ON voltage 5V. That is, it can be seen that if the on-voltage is set to be twice or more the threshold voltage V10, the contrast is improved.
In the table of FIG. 2, in the range where the ON voltage is less than twice the threshold voltage V10 (cell gap d is 4 to 6 μm and θp is 4 °), the contrast is “89”, “56”. ”And“ 40 ”, it can be seen that it is useful to set the ON voltage as in condition 4.

  Next, the influence of the cell gap d and the pretilt angle θp on the transmittance will be described with reference to a VT (voltage-transmittance) curve in FIG. The graph of FIG. 3 is drawn based on the data shown in FIGS. 4A and 4B, and this data is derived by the same simulation as described above. In this simulation, as a liquid crystal display element, a cell gap d and a pretilt angle θp satisfying the above conditions (d = 2.5 μm, θp = 4 °, hereinafter referred to as an example), and a pretilt angle θp Only that does not satisfy the condition (d = 2.5 μm, θp = 2 °, hereinafter referred to as Comparative Example 1), and only the cell gap d that does not satisfy the condition (d = 6 μm, θp = 4 °) (Hereinafter referred to as Comparative Example 2).

  Referring to FIG. 3, when the curve C1 according to the example, the curve C2 according to the comparative example 1, and the curve C3 according to the comparative example 2 are compared, the example is more on the on-voltage (5V) than the comparative examples 1 and 2. It can be seen that the transmittance of is low. Specifically, as shown in FIG. 4B, when the voltage is 5 V, the transmittance of the example is “0.1984”, the transmittance of Comparative Example 1 is “0.2373”, and the transmittance of Comparative Example 2 is. The rate is lower than “0.8149”. For this reason, in the Example, it turns out that the display element 4 (refer FIG.1 (b)) can be displayed more black. On the other hand, when no voltage is applied, the transmittance of the example is “31.4035”, the transmittance of the comparative example 1 is “31.4748”, and the transmittance of the comparative example 2 is shown in FIG. “32.6649”, although the transmittance of the example is slightly lower than the transmittance of Comparative Examples 1 and 2 (the higher the transmittance when no voltage is applied, the better). It is the value of. From this, it can be seen that the example has better contrast than Comparative Examples 1 and 2.

The liquid crystal display element 100 described above includes a pair of substrates 11 and 12 facing each other, a liquid crystal layer 13 positioned between the pair of substrates 11 and 12, and a liquid crystal layer 13 side of each of the pair of substrates 11 and 12. A liquid crystal cell 10 having transparent electrodes 11a and 12a provided, a pair of polarizing plates 21 and 22 facing each other across the liquid crystal cell 10, and between the liquid crystal cell 10 and the pair of polarizing plates 21 and 22 A twisted nematic type liquid crystal display device 100 having a viewing angle widening film 31 and 32 positioned thereon, and a voltage is applied to the transparent electrodes 11a and 12a by a static drive method, and the thickness of the liquid crystal layer 13 (cell gap d ) Is 2 μm or more and 3 μm or less, the retardation (Δnd) value of the liquid crystal layer 13 is 0.25 μm or more and 0.5 μm or less, and the pretilt angle θp of the liquid crystal layer 13 is 3 °. And the upper 5 ° or less, the on-voltage by static driving is more than twice the threshold voltage V10 of the liquid crystal layer 13.
Thus, since the liquid crystal display element 100 is configured to satisfy the conditions 1 to 4, the contrast is good as described above. In addition, since a viewing angle widening film is provided, the contrast is good at a wide viewing angle.
The retardation value of the liquid crystal layer 13 may be 0.3 μm or more and 0.4 μm or less, and the pretilt angle θp of the liquid crystal layer 13 may be 4 ° or more and 5 ° or less. In this way, a better contrast can be realized.

  In addition, this invention is not limited by said embodiment and drawing. Of course, changes (including deletion of components) can be added to these. For example, in the above description, the viewing angle widening films 31 and 32 are provided on both sides of the front and back of the liquid crystal cell 10, but may be provided on one side of the liquid crystal cell 10. In the above description, the liquid crystal display element 100 has been described as a positive display type. However, the polarizing plates 21 and 22 are arranged in a parallel Nicol relationship so that their transmission axes are substantially parallel to each other. (Normally black mode).

  In the above description, in order to facilitate the understanding of the present invention, the description of known unimportant technical matters is appropriately omitted.

100 ... Liquid crystal display element
1… Observer
2 ... Drive IC
3 ... Background area
DESCRIPTION OF SYMBOLS 4 ... Display element 10 ... Liquid crystal cell 11, 12 ... Substrate 11a, 12a ... Transparent electrode 11b, 12b ... Alignment film 13 ... Liquid crystal layer 21, 22 ... Polarizing plate 31, 32 ... Viewing angle expansion film 40 ... Backlight

Claims (2)

A liquid crystal cell having a pair of substrates facing each other, a liquid crystal layer positioned between the pair of substrates, and a transparent electrode provided on the liquid crystal layer side of each of the pair of substrates;
A pair of polarizing plates facing each other across the liquid crystal cell;
A viewing angle widening film positioned between the liquid crystal cell and at least one of the pair of polarizing plates,
A twisted nematic liquid crystal display element in which a voltage is applied to the transparent electrode by a static drive method,
The liquid crystal layer has a thickness of 2 μm or more and 3 μm or less,
The retardation value of the liquid crystal layer is 0.25 μm or more and 0.5 μm or less,
The pretilt angle of the liquid crystal layer is 3 ° or more and 5 ° or less,
The ON voltage by static drive is more than twice the threshold voltage of the liquid crystal layer,
The liquid crystal display element characterized by the above-mentioned. The retardation value of the liquid crystal layer is 0.3 μm or more and 0.4 μm or less,
The pretilt angle of the liquid crystal layer is 4 ° or more and 5 ° or less,
The liquid crystal display element according to claim 1.

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