JPH1090644A - Color liquid crystal display panel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a color display by using the double refraction effect of a liquid crystal or phase difference plate without using a color filter. SOLUTION: A liquid crystal cell 6 is held between a top side polarizing plate 1 and a back side polarizing plate 5, and uniaxially oriented phase difference plates 12, 13 are held between the top side polarizing plate 1 and a transparent substrate 2 of the liquid crystal cell 6. The liquid crystal molecules of the liquid crystal cell are oriented at 100 to 270 deg. twisting angle, and ΔnLC.dLC, of the liquid crystal layer is controlled to 1.2 to 2.2μm. The hue of the single plate of the top side polarizing plate (according to Hunter Lab series in NBS unit) is controlled to -2.0 to 2.0 for a and -8.0 to 0.0 for b. By this constitution, the obtd. color liquid crystal display panel realizes a display with whiteness when voltage is applied, higher color purity, larger numbers of colors and low cost.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a color liquid crystal display panel.

[0002]

2. Description of the Related Art A conventional color liquid crystal display panel capable of obtaining a colored display comprises a liquid crystal cell provided with a color filter and a pair of polarizing plates disposed so as to sandwich the liquid crystal cell. The color filter is provided on one of the substrates of the liquid crystal cell, and the color filter is formed on the substrate, and the transparent electrode is formed thereon. The liquid crystal cell is subjected to a twist alignment process, and the liquid crystal layer takes two states, that is, whether the liquid crystal layer rises or stays twisted depending on whether a voltage is applied or not. By combining this with a polarizing plate, the incident light is transmitted to provide a bright display of the color colored by the color filter, or the incident light is blocked, resulting in a dark (black) display.

However, a color liquid crystal display panel using a color filter has a problem that the light transmittance is low and the display is dark because a colored light is obtained using the color filter.

Therefore, a color liquid crystal display device in which light is colored by a birefringence of a liquid crystal layer of a liquid crystal cell and a polarizing plate without using a color filter (JP-A-06-308481),
A color liquid crystal display device utilizing not only a liquid crystal layer but also birefringence of a retardation plate (Japanese Patent Application Laid-Open Nos. 06-175125 and 06-175125).
301006) has been proposed.

[0005]

The color liquid crystal display device using the above-mentioned conventional color filter has a problem that the light transmittance is low, which is due to the absorption of light by the color filter. .

A color liquid crystal display device in which light is colored by the birefringence of a liquid crystal layer of a liquid crystal cell and a polarizing plate (Japanese Patent Application Laid-Open No. H06-3)
No. 08481) is slightly colored white, the number of colors that can be displayed is small, and the color purity of the color is low.

A color liquid crystal display device utilizing not only a liquid crystal layer but also birefringence of a retardation plate (Japanese Patent Laid-Open No. 06-175125,
In Japanese Patent Application Laid-Open No. 06-301006, the white color is slightly colored and the color purity of the displayable color is low.

SUMMARY OF THE INVENTION An object of the present invention is to provide a color liquid crystal display panel having good color purity by coloring transmitted light without using a color filter, suppressing white coloring.

[0009]

A first means for solving the above problems is to sandwich a liquid crystal between two upper and lower electrode substrates having transparent electrodes formed on opposing surfaces, and to move the liquid crystal molecules up and down. The liquid crystal is anisotropically twisted between 100 ° and 270 ° between the electrode substrates, and has an optical anisotropy Δn _LC of the liquid crystal and a liquid crystal layer thickness d _LC of the liquid crystal.
(Μm) △ n _LC · d _LC is 1.2 μm to 2.2 μm
And a liquid crystal cell arranged between the liquid crystal cells.
A polarizing plate, and the transmission axis of the polarizing plate is shifted at an angle of 45 ° ± 10 ° with respect to the liquid crystal molecule alignment direction on the polarizing plate adjacent substrate side of the liquid crystal cell. The hue (Hunter's Lab color system, NBS unit) is as follows: a is -2.0 to +2.0, b is -8.0 to 0.
It is characterized by being in the range of 0.

The first means can be applied to both a transmission type color liquid crystal display panel and a reflection type color liquid crystal display panel. When the first means is applied to a reflection type panel, the outer surface of the polarizing plate on the back side is used. Is provided with a reflector. Further, at least one retardation plate may be disposed between the liquid crystal cell and the polarizing plate on the front side.

When a retardation plate is arranged, the slow axis of the retardation plate adjacent to the liquid crystal cell is shifted by 90 ° ± 10 ° with respect to the liquid crystal molecule alignment direction on the side of the substrate adjacent to the retardation plate of the liquid crystal cell. It is desirable to shift the transmission axis of the front-side polarizing plate obliquely by 45 ° ± 10 ° with respect to the slow axis of the phase difference plate adjacent to the polarizing plate.

Further, it is desirable to use a three-dimensional refractive index controlled product for the phase difference plate. A second means for solving the above problem is to sandwich a liquid crystal between two upper and lower electrode substrates each having a transparent electrode formed on the opposing surface, and to disperse the molecules of the liquid crystal by 200 ° between the upper and lower electrode substrates. ~ 270 ° twist orientation,
The optical anisotropy Δn _LC of the liquid crystal and the liquid crystal layer thickness d of the liquid crystal
The product of _LC (μm) Δn _LC · d _LC is 1.2 μm to 2.2 μm
m, a liquid crystal cell, two polarizing plates sandwiching the liquid crystal cell, and one retardation plate disposed between the liquid crystal cell and a polarizing plate on the surface side, The product of the refractive index anisotropy △ n _{F of the} retardation plate △ n _F and the plate thickness d _F △ n _F · d _F becomes △
n _LC · d _LC − (0.10 μm to 0.20 μm).

This second means can be applied to both a transmission type color liquid crystal display panel and a reflection type color liquid crystal display panel. When the second means is applied to a reflection type panel, the outer surface of the polarizing plate on the back side is used. Is provided with a reflector.

Further, the slow axis of the phase difference plate adjacent to the liquid crystal cell is shifted by 90 ° ± 10 ° with respect to the liquid crystal molecule alignment direction on the side of the substrate adjacent to the phase difference plate of the liquid crystal cell. It is desirable that the axis be inclined at an angle of 45 ° ± 10 ° with respect to the slow axis of the phase difference plate adjacent to the polarizing plate.

It is desirable that the transmission axis of the rear-side polarizing plate is inclined by 45 ° ± 10 ° with respect to the liquid crystal molecule alignment direction on the substrate adjacent to the polarizing plate of the liquid crystal cell.

Further, the hue (Hu) of the simple substance of the polarizing plate on the front surface side is obtained.
lab color system, NBS unit).
It is desirable that 0 to +2.0 and b be in the range of -8.0 to 0.0.

Further, it is desirable to use a three-dimensional refractive index controlled product for the phase difference plate. Further, a third means for solving the above problem is to sandwich a liquid crystal between two upper and lower electrode substrates having transparent electrodes formed on opposing surfaces, and to disperse the molecules of the liquid crystal between the upper and lower electrode substrates by 200 ° to 200 °. 270 ° twist alignment, the optical anisotropy Δn _LC of the liquid crystal and the liquid crystal layer thickness d _LC of the liquid crystal
(Μm) △ n _LC · d _LC is 1.2 μm to 2.2 μm
And a liquid crystal cell arranged between the liquid crystal cells.
A polarizing plate, and at least two retardation plates disposed between the liquid crystal cell and the front-side polarizing plate, wherein the refractive index anisotropy Δn _F and the plate thickness d of the retardation plate the product of the _F △ n _F ·
The sum of d _F is Δn _LC · d _LC − (0.10 μm to 0.2
0 μm).

In the third means, the retardation plate is arranged such that the retardation axis of the retardation plate adjacent to the liquid crystal cell is set at 30 ° with respect to the slow axis of the retardation plate adjacent to the front-side polarizing plate. It is desirable to shift within.

Further, the present invention can be applied to both a transmission type color liquid crystal display panel and a reflection type color liquid crystal display panel. When the present invention is applied to a reflection type panel, a reflection plate is provided on an outer surface of a rear polarizing plate. .

Further, the slow axis of the phase difference plate adjacent to the liquid crystal cell is shifted by 90 ° ± 10 ° with respect to the liquid crystal molecule alignment direction on the side of the substrate adjacent to the phase difference plate of the liquid crystal cell. It is desirable that the axis be inclined at an angle of 45 ° ± 10 ° with respect to the slow axis of the phase difference plate adjacent to the polarizing plate.

It is preferable that the transmission axis of the rear-side polarizing plate is inclined by 45 ° ± 10 ° with respect to the liquid crystal molecule alignment direction on the substrate adjacent to the polarizing plate of the liquid crystal cell.

The hue (Hu) of the polarizing plate on the front side alone is
lab color system, NBS unit).
It is desirable that 0 to +2.0 and b be in the range of -8.0 to 0.0.

Further, it is desirable to use a three-dimensional refractive index controlled product for the phase difference plate. A fourth means for solving the above-mentioned problem is to sandwich a liquid crystal between two upper and lower electrode substrates having transparent electrodes formed on opposing surfaces, and to disperse the molecules of the liquid crystal between the upper and lower electrode substrates by 200 ° to 200 °. 270 ° twist alignment, the optical anisotropy Δn _LC of the liquid crystal and the liquid crystal layer thickness d _LC of the liquid crystal
(Μm) △ n _LC · d _LC from 1.2 μm to 2.2 μm
m, a liquid crystal cell, two polarizing plates sandwiching the liquid crystal cell, and one retardation plate disposed between the liquid crystal cell and a polarizing plate on the surface side, The product of the refractive index anisotropy △ n _{F of the} retardation plate △ n _F and the plate thickness d _F △ n _F · d _F becomes △
n _LC · d _LC + (0.05 μm to 0.15 μm).

The fourth means can be applied to both a transmission type color liquid crystal display panel and a reflection type color liquid crystal display panel. When the fourth means is applied to a reflection type panel, the outer surface of the polarizing plate on the back side is used. Is provided with a reflector.

Also, the slow axis of the phase difference plate adjacent to the liquid crystal cell is shifted by 90 ° ± 10 ° with respect to the liquid crystal molecule alignment direction on the side of the substrate adjacent to the phase difference plate of the liquid crystal cell. It is desirable that the axis be inclined at an angle of 45 ° ± 10 ° with respect to the slow axis of the phase difference plate adjacent to the polarizing plate.

It is preferable that the transmission axis of the rear-side polarizing plate is shifted by 45 ° ± 10 ° with respect to the liquid crystal molecule alignment direction on the side of the liquid crystal cell adjacent to the polarizing plate.

Further, the hue (Hu) of the simple substance of the polarizing plate on the front surface side is obtained.
lab color system, NBS unit).
It is desirable that 0 to +2.0 and b be in the range of -8.0 to 0.0.

Further, it is desirable to use a three-dimensional refractive index controlled product for the phase difference plate. A fifth means for solving the above-mentioned problem is that a liquid crystal is sandwiched between two upper and lower electrode substrates having transparent electrodes formed on opposing surfaces, and molecules of the liquid crystal are transferred between the upper and lower electrode substrates by 200 ° to 200 °. 270 ° twist alignment, the optical anisotropy Δn _LC of the liquid crystal and the liquid crystal layer thickness d _LC of the liquid crystal
(Μm) △ n _LC · d _LC is 1.2 μm to 2.2 μm
And a liquid crystal cell arranged between the liquid crystal cells.
A polarizing plate, and at least two retardation plates disposed between the liquid crystal cell and the front-side polarizing plate, wherein the refractive index anisotropy Δn _F and the plate thickness d of the retardation plate the product of the _F △ n _F ·
The sum of d _F is Δn _LC · d _LC + (0.05 μm to 0.1
5 μm).

In the fifth means, the retardation plate is arranged such that the retardation axis of the retardation plate adjacent to the liquid crystal cell is set at 30 ° with respect to the slow axis of the retardation plate adjacent to the front-side polarizing plate. It is desirable to shift within.

The present invention can be applied to both a transmission type color liquid crystal display panel and a reflection type color liquid crystal display panel. When applied to a reflection type panel, a reflection plate is provided on the outer surface of the polarizing plate on the back side. .

Further, the slow axis of the phase difference plate adjacent to the liquid crystal cell is shifted by 90 ° ± 10 ° with respect to the liquid crystal molecule alignment direction on the side of the substrate adjacent to the phase difference plate of the liquid crystal cell. It is desirable that the axis be inclined at an angle of 45 ° ± 10 ° with respect to the slow axis of the phase difference plate adjacent to the polarizing plate.

Preferably, the transmission axis of the back-side polarizing plate is shifted by 45 ° ± 10 ° with respect to the liquid crystal molecule alignment direction on the side of the liquid crystal cell adjacent to the polarizing plate.

Also, the hue (Hu) of the single polarizer on the front side is
lab color system, NBS unit).
It is desirable that 0 to +2.0 and b be in the range of -8.0 to 0.0.

Furthermore, it is desirable to use a three-dimensional refractive index controlled product for the phase difference plate.

[0035]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The details of the present invention will be described below using embodiments.

(Embodiment 1) Hereinafter, an embodiment of the first invention will be described with reference to FIGS.

FIG. 1 is a sectional view of a color liquid crystal display panel according to the first embodiment of the present invention. This color liquid crystal display panel has one liquid crystal cell 6 in which liquid crystal molecules 4 are twisted.
And a pair of polarizing plates 1 and 5 disposed with the liquid crystal cell 6 interposed therebetween.
Consists of

The liquid crystal cell 6 is of a simple matrix type. The electrodes 3 on the front transparent substrate 2 are a plurality of scanning electrodes formed in parallel with each other, and the electrodes 3 on the rear transparent substrate 2 are scanning electrodes. An orientation film is applied on a plurality of signal electrodes formed in a direction perpendicular to the substrate, and a particle size of 7.0 μm
Was sprayed, and a sealant was printed on the periphery and then bonded. A trans nematic liquid crystal (Δn = 0.2) having a chiral pitch of 18.42 μm was sealed after vacuum injection.

FIG. 2 is a plan view showing the liquid crystal molecule alignment directions 9 and 10 of the liquid crystal cell 6 and the transmission axes 8 and 11 of a pair of polarizing plates. The angle between the liquid crystal molecule orientation direction 9 of the front side transparent substrate, the liquid crystal molecule orientation direction 10 of the back side transparent substrate and the reference line 7 is θ1 = 165 °, θ2 = 195 °, and the liquid crystal molecules are oriented from the back side to the front side. Was twist-oriented at a twist angle of about 150 °. The angle between the transmission axis 8 of the front-side polarizing plate, the transmission axis 11 of the rear-side polarizing plate and the reference line 7 is ξ1 = 12.
0 ° and {2 = 60}.

The hue of the polarizing plate alone (Hunter's Lab color system, NBS unit) is
NPF-F1 where (a, b) ≒ (0.5, −7.0)
025DU (manufactured by Nitto Denko Corporation) was used.

In the color liquid crystal display panel having the above structure, in a state where the liquid crystal molecules of the liquid crystal cell are twisted, the linearly polarized light that has entered the liquid crystal cell through one polarizing plate passes through the liquid crystal cell while passing through the liquid crystal cell. The light becomes elliptically polarized light due to the birefringence of the cell, and enters the other polarizing plate.

When a voltage is applied between the electrodes of the liquid crystal cell, the birefringence in the liquid crystal cell changes due to a change in the alignment state of the liquid crystal molecules. When the light enters the plate and the liquid crystal molecules rise almost vertically, the birefringence of the liquid crystal cell hardly disappears, and the linearly polarized light that has entered through one polarizing plate enters the other polarizing plate in the same polarization state.

If the light incident on one of the polarizing plates is the same linearly polarized light as the light emitted from the other polarizing plate, all the wavelengths of light pass through the polarizing plate, and the emitted light is uncolored at this time. .

When the light incident on the other polarizing plate is elliptically polarized light, only the light having the wavelength of the polarization component transmitted through the polarizing plate is transmitted through the other polarizing plate, and the emitted light is It becomes colored light corresponding to the wavelength band.

Since the wavelength band of the light emitted through the other polarizing plate differs depending on the polarization state of the elliptically polarized light incident on the polarizing plate, the voltage applied to the liquid crystal cell is controlled to control the polarization state of the elliptically polarized light. Is changed, the color of the colored light can be changed.

Further, the Δn _LC · d _LC of the liquid crystal layer is 1.4 μm.
m, 150 ° twist orientation, when no voltage is applied,
Since the light incident on one of the polarizing plates becomes linearly polarized light substantially equal to that after exiting the other polarizing plate, a color closer to white can be displayed.

FIG. 3 shows a CIE chromaticity diagram showing a color change of colored light when a backlight is installed on the color liquid crystal display panel having the above-described structure and a voltage is applied.

A conventional color liquid crystal display panel (Japanese Unexamined Patent Publication No.
308481), the CIE chromaticity coordinates (x, y) are
White (0.36, 0.29), red (0.46, 0.3
9) and blue (0.25, 0.22), but from FIG. 3, the CIE chromaticity coordinates (x, y) when no voltage is applied (0. 33, 0.
34), and a D65 white light source (0.3
127, 0.3291) and red (0.50, 0.
34), and a color liquid crystal display panel having good color purity (0.19, 0.15) and blue (0.19, 0.15) can be provided at low cost because there is no color filter.

The twist angle is as small as 150 °, the orientation of liquid crystal molecules is easily stabilized, and the display capacity is small.

In this embodiment, the liquid crystal cell 6 has a twist angle of the liquid crystal molecules 4 of about 150 ° and the liquid crystal layer has a Δn _LC · d _LC of 1.40 μm. The liquid crystal molecules 4 may be twist-oriented at a twist angle of 100 ° to 270 °, and the Δn _LC · d _LC of the liquid crystal layer may be 1.2 μm to 2.2 μm.

In order to suppress yellow with high luminosity and to obtain a white display with little coloring when no voltage is applied, it is necessary to use a single hue (Hunter's Lab color system,
A) is -2.0 to +2.0, b is -8.
It is desirable to set it in the range of 0 to 0.0.

In the present embodiment, the transmission axes 8 and 11 of the polarizing plates and the liquid crystal molecule orientation directions 9 and
Although the angle of deviation from 10 is 45 °, the angle of deviation is desirably 45 ° ± 10 °.

In this embodiment, the color liquid crystal display panel is of a transmission type in which a backlight is provided. However, a reflection type color liquid crystal display panel may be provided by attaching a reflection plate outside the back side polarizing plate. .

In this embodiment, the polarizing plate is directly disposed on the surface of the liquid crystal cell. However, at least one retardation plate may be disposed between the liquid crystal cell and the polarizing plate on the surface. . When a retardation plate is disposed, the slow axis of the retardation plate adjacent to the liquid crystal cell is shifted by 90 ° ± 10 ° with respect to the liquid crystal molecule alignment direction on the substrate adjacent to the retardation plate of the liquid crystal cell. It is desirable to shift the transmission axis of the plate obliquely by 45 ° ± 10 ° with respect to the slow axis of the phase difference plate adjacent to the polarizing plate. Further, it is desirable to use a three-dimensional refractive index controlled product for the retardation plate.

(Embodiment 2) Hereinafter, an embodiment of the second invention will be described with reference to FIGS.

FIG. 4 is a sectional view of a color liquid crystal display panel according to the second and fourth embodiments of the present invention. This color liquid crystal display panel includes one liquid crystal cell 6 in which liquid crystal molecules 4 are twist-aligned, a pair of polarizing plates 1 and 5 arranged with the liquid crystal cell 6 interposed therebetween, and a liquid crystal cell 6 and a polarizing plate 1 on the front side. And one retardation plate 12 disposed between the two.

The liquid crystal cell 6 is of a simple matrix type. The electrodes 3 on the front transparent substrate 2 are a plurality of scanning electrodes formed in parallel with each other, and the electrodes 3 on the rear transparent substrate 2 are the scanning electrodes. An orientation film is applied on a plurality of signal electrodes formed in a direction perpendicular to the direction of the substrate, and a particle size between the two substrates is 9.5 μm.
Was sprayed, and a sealant was printed on the periphery and then bonded. A trans-nematic liquid crystal (Δn _LC = 0.2) having a chiral pitch of 15.8 μm was sealed after vacuum injection.

FIG. 5 shows the liquid crystal molecule alignment directions 9 and 10 of the liquid crystal cell 6, the slow axis direction 14 of one polycarbonate uniaxially stretched retardation plate, and the transmission axes 8 and 11 of a pair of polarizing plates.
FIG. The angle between the liquid crystal molecule orientation direction 9 of the front side transparent substrate, the liquid crystal molecule orientation direction 10 of the back side transparent substrate and the reference line 7 is θ1 = 215 °, θ2 = 145 °,
The liquid crystal molecules 4 are moved from the back side to the front side by approximately 250
Twist orientation was performed at a twist angle of ゜. The angle between the slow axis direction 14 of the uniaxially stretched phase difference plate and the reference line 7 is ψ1 = 121
゜, Δn _F1 · d _F1 = 1.726 μm. The angles between the transmission axis 8 of the front-side polarizing plate, the transmission axis 11 of the rear-side polarizing plate, and the reference line 7 were {1 = 76} and {2 = 100}.

The front side polarizing plate 1 is provided with the hue (Hunter's Lab color system, NBS unit) of the polarizing plate alone.
NPF-G where (a, b) ≒ (−1.0, + 2.0)
1225DU (manufactured by Nitto Denko Corporation) was used.

In the color liquid crystal display panel, the transmitted light is colored by the birefringence of the retardation plate, and the transmitted light is colored by the birefringence of the retardation plate and the birefringence of the liquid crystal in which the liquid crystal molecules are twisted. It is colored in another color.

When no voltage is applied between the electrodes of the liquid crystal cell, the light incident through one of the polarizers is caused by the birefringence of the twist-aligned liquid crystal molecules and the birefringence of the retardation plate. When the light is transmitted through the polarizing plate, the light becomes uncolored light.

When a voltage is applied between the electrodes of the liquid crystal cell, the birefringence in the liquid crystal cell changes in response to the change in the alignment state of the liquid crystal molecules. Therefore, coloring due to the birefringence of both the retardation plate and the liquid crystal cell. The color of the light changes.

When a voltage is further applied and the liquid crystal molecules rise almost perpendicularly to the substrate surface, the birefringence of the liquid crystal cell almost disappears, and the light transmitted through the other polarizing plate is reduced by the birefringence of the retardation plate. It becomes colored light only by.

Further, Δn _LC · d _LC of the liquid crystal layer was set to 1.9 μm.
m, 250 ° is twisted, if the product △ n _F · d _F of the refractive index anisotropy △ n _F and the plate thickness d _F of the phase difference plate was 1.726Myuemu, the off voltage applied state, the one Since the light incident on the polarizing plate becomes linearly polarized light substantially equal to that after exiting the other polarizing plate, a color closer to white can be displayed.

A backlight is installed on the color liquid crystal display panel having the above-described structure, and is driven by a voltage of (1/200) to (1/240) duty and (1/14) to (1/17) bias. It was controlled by the frame rate control method.

FIG. 6 shows a CIE chromaticity diagram showing the color change of the colored light when a voltage is applied. The CIE chromaticity coordinates (x, y) of a conventional color liquid crystal display panel (JP-A-6-308481) are white (0.36, 0.29), red (0.46, 0.39), blue (0, 0). .25, 0.2
2) and green (0.27, 0.47), and FIG. 6 shows that the CIE chromaticity coordinates (x, y) when the off-voltage is applied are (0, 0) by adopting the panel configuration of the present embodiment. .3
3, 0.35), which is closer to the D65 white light source (0.3127, 0.3291) and red (0.4
8, 0.30), blue (0.22, 0.21) and green (0.33, 0.50).

In the present embodiment, the liquid crystal cell 6 has a twist angle of the liquid crystal molecules 4 of approximately 250 °, the liquid crystal layer has a Δn _LC · d _LC of 1.90 μm, and a single retardation plate 1.
2 of △ n _F · d _F was a 1.726Myuemu, the liquid crystal cell 6 may also be twisted liquid crystal molecules 4 at 200 ° to 270 ° twist angle of the liquid crystal layer △ n _LC · d _LC may be from 1.2 μm to 2.2 μm, and the product Δn _F · d _F of the refractive index anisotropy Δn _{F of the} retardation plate and the plate thickness d _F is Δn _LC ·
d _LC - may be in a range of (0.10μm~0.20μm).

In this embodiment, the front-side polarizing plate 1
Used a polarizing plate whose hue is (a, b) ≒ (−1.0, + 2.0). However, when an off-voltage is applied, yellow with high luminosity is suppressed, and white display with little coloring is performed. In order to obtain the hue (Hunt) of the polarizing plate alone of the front-side polarizing plate,
er Lab color system, NBS unit), a is -2.0 to
It is desirable to use a front-side polarizing plate having +2.0 and b in the range of -8.0 to 0.0.

In this embodiment, polycarbonate is used for the uniaxially stretched retardation plate 12, but polyvinyl alcohol, polyarylate, polyether sulfone, or the like may be used.

Further, in the present embodiment, in the arrangement of the front-side polarizing plate and the retardation plate, the slow axis of the adjacent retardation plate of the liquid crystal cell with respect to the liquid crystal molecule alignment direction on the side of the substrate adjacent to the retardation plate of the liquid crystal cell. Although the shift angle is 94 °, the shift angle is desirably 90 ° ± 10 °.

Further, the shift angle of the transmission axis of the front-side polarizing plate with respect to the slow axis of the phase difference plate adjacent to the front-side polarizing plate was set to 45 °, and this shift angle was set to 45 ° ± 10 °. Is desirable.

In the present embodiment, the shift angle between the transmission axis 11 of the rear-side polarizing plate and the liquid crystal molecule orientation direction 10 of the substrate adjacent to the rear-side polarizing plate is set to 45 °.
It is desirable to be 5 ± 10 °.

Further, in this embodiment, the transmission type is a color liquid crystal display panel having a backlight, but a reflection type color liquid crystal display panel may be provided by attaching a reflection plate outside the back side polarizing plate. . In the case of a reflective type color liquid crystal display panel, the deviation angle between the transmission axis 11 of the rear-side polarizing plate and the liquid crystal molecule orientation direction 10 of the polarizing plate adjacent substrate adjacent to the reflecting plate 16 is set to 45 ° ± 10 °. But desirable.

Further, in order to obtain a color liquid crystal display panel having a wider viewing angle, the birefringence when the panel is viewed from the front and the birefringence when the panel is viewed at an angle are applied to the uniaxially stretched retardation plate 12. It is desirable to use a three-dimensional refractive index controlled product that can reduce the difference between the two.

(Embodiment 3) Hereinafter, an embodiment of the third invention will be described with reference to FIGS.

FIG. 7 is a sectional view of a color liquid crystal display panel according to the third and fifth embodiments of the present invention. This color liquid crystal display panel includes one liquid crystal cell 6 in which liquid crystal molecules 4 are twist-aligned, a pair of polarizing plates 1 and 5 arranged with the liquid crystal cell 6 interposed therebetween, and a liquid crystal cell 6 and a polarizing plate 1 on the front side. And two retardation plates 12 and 13 disposed between the two.

The liquid crystal cell 6 is of a simple matrix type. The electrodes 3 on the front transparent substrate 2 are a plurality of scanning electrodes formed in parallel with each other, and the electrodes 3 on the rear transparent substrate 2 are scanning electrodes. An alignment film is applied on a plurality of signal electrodes formed in a direction perpendicular to the substrate, and a particle size of 9.0 μm
Was sprayed, and a sealant was printed on the periphery and then bonded. A trans nematic liquid crystal (の n _LC = 0.2) having a chiral pitch of 15.0 μm was sealed after vacuum injection.

FIG. 8 shows the liquid crystal molecule alignment directions 9 and 10 of the liquid crystal cell 6, the slow axis directions 14 and 15 of the two polycarbonate uniaxially stretched retardation plates, and the transmission axes 8 and 11 of the pair of polarizing plates. FIG. Liquid crystal molecule orientation direction 9 of front transparent substrate, liquid crystal molecule orientation direction 1 of rear transparent substrate
The angle between 0 and the reference line 7 is θ1 = 215 °, θ2 = 145
The liquid crystal molecules 4 were twist-oriented at a twist angle of about 250 ° from the back side to the front side. The angle between the slow axis direction 14 of the uniaxially stretched phase difference plate adjacent to the front side polarizing plate 1 and the reference line 7 is { ₁ = 149}, Δn _F1 · d
_F1 = 1.000 μm, the angle between the slow axis direction 15 of the uniaxially stretched phase difference plate adjacent to the liquid crystal cell 6 and the reference line 7 is { ₂ = 131.5}, and Δn _F2 · d _F2 = 0. It was 650 μm. The angles of the transmission axis 8 of the front-side polarizing plate, the transmission axis 11 of the rear-side polarizing plate, and the reference line 7 are {1 = 110} and ξ2 = 10.
0 °.

The hue (Hunter's Lab color system, NBS unit) of the polarizing plate alone is applied to the front-side polarizing plate 1.
NPF-F where (a, b) ≒ (−0.5, −1.0)
1225DU (manufactured by Nitto Denko Corporation) was used.

In the color liquid crystal display panel, the transmitted light is colored by the birefringence of the retardation plate, and the transmitted light is transmitted by the birefringence of the retardation plate and the birefringence of the liquid crystal in which the liquid crystal molecules are twisted. It is colored in another color.

In the state where no voltage is applied between the electrodes of the liquid crystal cell, the light incident through one of the polarizing plates is changed by the birefringence of the twist-aligned liquid crystal molecules and the birefringence of the retardation plate. When the light is transmitted through the polarizing plate, the light becomes uncolored light.

When a voltage is applied between the electrodes of the liquid crystal cell, the birefringence in the liquid crystal cell changes in response to the change in the alignment state of the liquid crystal molecules. Therefore, coloring due to the birefringence of both the retardation plate and the liquid crystal cell. The color of the light changes.

Further, when a voltage is applied to cause the liquid crystal molecules to rise almost perpendicularly to the substrate surface, birefringence by the liquid crystal cell is almost eliminated, and the light transmitted through the other polarizing plate is reduced by the birefringence of the retardation plate. It becomes colored light only by.

The Δn _LC · d _LC of the liquid crystal layer was 1.8 μm.
m, 250} twist oriented, and the sum of the product Δn _F · d _F of the refractive index anisotropy Δn _{F of the} retardation plate and the plate thickness d _F is 1.650.
In the case where the shift of the slow axes of the two retardation plates is 17.5 ° in μm, the linearly polarized light in which the light incident on one of the polarizers is almost equal to the light emitted from the other polarizer in the off-voltage applied state Therefore, a color closer to white can be displayed.

A backlight is installed on the color liquid crystal display panel having the above configuration, and is driven by a voltage of (1/200) to (1/240) duty and (1/14) to (1/17) bias. It was controlled by the frame rate control method.

FIG. 9 is a CIE chromaticity diagram showing a color change of colored light when a voltage is applied. The CIE chromaticity coordinates (x, y) of a conventional color liquid crystal display panel (JP-A-6-308481) are white (0.36, 0.29), red (0.46, 0.39), blue (0, 0). .25, 0.2
2) and green (0.27, 0.47), and FIG. 9 shows that the CIE chromaticity coordinates (x, y) when the off-voltage is applied are (0, 0) by adopting the panel configuration of the present embodiment. .3
2, 0.34), which is closer to the D65 white light source (0.3127, 0.3291) and red (0.4
7, 0.29), blue (0.21, 0.20), and green (0.32, 0.49).

In this embodiment, the liquid crystal cell 6 has a twist angle of the liquid crystal molecules 4 of about 250 °, a liquid crystal layer having a Δn _LC · d _LC of 1.80 μm, and two retardation plates 1.
Δn _F · d _F of 2.13 is 1.000 μm, 0.650 μ
m, the liquid crystal cell 6 may have the liquid crystal molecules 4 twist-oriented at a twist angle of 200 ° to 270 °,
The Δn _LC · d _LC of the liquid crystal layer may be 1.2 μm to 2.2 μm, and the sum of the product Δn _F · d _F of the refractive index anisotropy Δn _{F of the} retardation plate and the plate thickness d _F. Is Δn _LC · d _LC − (0.10 μm ~
0.20 μm).

In the present embodiment, the front-side polarizing plate 1
Used a polarizing plate whose hue is (a, b) ≒ (−0.5, −1.0), but suppresses yellow with strong luminosity due to the application of off-voltage, and has little coloration. To obtain the display, the hue (Hunt) of the polarizing plate alone of the front-side polarizing plate is required.
er Lab color system, NBS unit), a is -2.0 to
It is desirable to use a front-side polarizing plate having +2.0 and b in the range of -8.0 to 0.0.

In this embodiment, polycarbonate is used for the uniaxially stretched retardation plates 12 and 13. However, polyvinyl alcohol, polyarylate, polyether sulfone, or the like may be used.

In the present embodiment, in the arrangement of the front-side polarizing plate and the retardation plate, the slow axis of the retardation plate adjacent to the liquid crystal cell with respect to the slow axis of the retardation plate adjacent to the front-side polarizing plate. Was set to 17.5 °, but this deviation angle was 30 °.
It is desirable to be within ゜.

Further, the shift angle of the slow axis of the adjacent retardation plate of the liquid crystal cell with respect to the liquid crystal molecule alignment direction on the side of the substrate adjacent to the retardation plate of the liquid crystal cell was set to 83.5 °. It is desirable to be 10 °.

Further, the shift angle of the transmission axis of the front-side polarizing plate with respect to the slow axis of the adjacent retardation plate of the front-side polarizing plate was 39 °, and this shift angle was 45 ° ± 10 °. Is desirable.

Further, in the present embodiment, the shift angle between the transmission axis 11 of the rear-side polarizing plate and the liquid crystal molecule orientation direction 10 of the substrate adjacent to the rear-side polarizing plate is set to 45 °.
It is desirable to be 5 ± 10 °.

In the present embodiment, the color liquid crystal display panel is of a transmission type in which a backlight is provided. However, a reflection type color liquid crystal display panel may be formed by attaching a reflection plate outside the back side polarizing plate. . In the case of a reflective type color liquid crystal display panel, the deviation angle between the transmission axis 11 of the rear-side polarizing plate and the liquid crystal molecule orientation direction 10 of the polarizing plate adjacent substrate adjacent to the reflecting plate 16 is set to 45 ° ± 10 °. Is desirable.

In order to obtain a color liquid crystal display panel having a wider viewing angle, two uniaxially stretched retardation plates 12 and 13 are provided.
In addition, it is desirable to use a three-dimensional refractive index control product that can reduce the difference between the birefringence when the panel is viewed from the front and the birefringence when the panel is viewed at an angle.

(Embodiment 4) Hereinafter, an embodiment of the fourth invention will be described with reference to FIGS. 4, 5, and 10. FIG.

FIG. 4 is a sectional view of a color liquid crystal display panel according to the second and fourth embodiments of the present invention. This color liquid crystal display panel includes one liquid crystal cell 6 in which liquid crystal molecules 4 are twist-aligned, a pair of polarizing plates 1 and 5 arranged with the liquid crystal cell 6 interposed therebetween, and a liquid crystal cell 6 and a polarizing plate 1 on the front side. And one retardation plate 12 disposed between the two.

The liquid crystal cell 6 is of a simple matrix type. The electrodes 3 on the front transparent substrate 2 are a plurality of scanning electrodes formed in parallel with each other, and the electrodes 3 on the rear transparent substrate 2 are scanning electrodes. An orientation film is applied on a plurality of signal electrodes formed in a direction perpendicular to the direction of the substrate, and a particle size between the two substrates is 9.5 μm.
Was sprayed, and a sealant was printed on the periphery and then bonded. A trans-nematic liquid crystal (Δn _LC = 0.2) having a chiral pitch of 15.8 μm was sealed after vacuum injection.

FIG. 5 shows the liquid crystal molecule alignment directions 9 and 10 of the liquid crystal cell 6, the slow axis direction 14 of one polycarbonate uniaxially stretched retardation plate, and the transmission axes 8 and 11 of a pair of polarizing plates.
FIG. The angle between the liquid crystal molecule orientation direction 9 of the front side transparent substrate, the liquid crystal molecule orientation direction 10 of the back side transparent substrate and the reference line 7 is θ1 = 215 °, θ2 = 145 °,
The liquid crystal molecules 4 were twisted at a twist angle of about 250 ° from the back side to the front side. The angle between the slow axis direction 14 of the uniaxially stretched retardation plate and the reference line 7 is {1 = 122.
5}, Δn _F1 · d _F1 = 1.966 μm. Transmission axis 8 of front-side polarizing plate, transmission axis 11 of back-side polarizing plate, and reference line 7
Are {1 = 169} and {2 = 100}.

The front-side polarizing plate 1 is provided with the hue (Hunter's Lab color system, NBS unit) of the polarizing plate alone.
LN-18 where (a, b) ≒ (−0.7, −0.7)
05T (produced by Poratechno) was used.

In the color liquid crystal display panel, the transmitted light is colored by the birefringence of the retardation plate, and the transmitted light is transmitted by the birefringence of the retardation plate and the birefringence of the liquid crystal in which the liquid crystal molecules are twisted. It is colored in another color.

When no voltage is applied between the electrodes of the liquid crystal cell, the light incident through one of the polarizing plates is changed by the birefringence of the twist-aligned liquid crystal molecules and the birefringence of the retardation plate. When the light is transmitted through the polarizing plate, the light becomes uncolored light.

When a voltage is applied between the electrodes of the liquid crystal cell, the birefringence in the liquid crystal cell changes in response to the change in the alignment state of the liquid crystal molecules. Therefore, coloring due to the birefringence of both the retardation plate and the liquid crystal cell. The color of the light changes.

Further, when a voltage is applied to cause the liquid crystal molecules to rise almost perpendicularly to the substrate surface, birefringence by the liquid crystal cell is almost eliminated, and the light transmitted through the other polarizing plate is reduced by the birefringence of the retardation plate. It becomes colored light only by.

The Δn _LC · d _LC of the liquid crystal layer was 1.9 μm.
m, 250 ° is twisted, if the product △ n _F · d _F of the refractive index anisotropy △ n _F and the plate thickness d _F of the phase difference plate was 1.966Myuemu, the off voltage applied state, the one Since light incident on the polarizing plate becomes linearly polarized light substantially equal to that after exiting the other polarizing plate, a color closer to white can be displayed.

A backlight is installed on the color liquid crystal display panel having the above configuration, and is driven by a voltage of (1/200) to (1/240) duty and (1/14) to (1/17) bias. It was controlled by the frame rate control method.

FIG. 10 is a CIE chromaticity diagram showing a color change of colored light when a voltage is applied. The CIE chromaticity coordinates (x, y) of a conventional color liquid crystal display panel (JP-A-6-308481) are white (0.36, 0.29), red (0.46, 0.39), blue (0, 0). .25, 0.2
2) and green (0.27, 0.47), and FIG. 10 shows that the CIE chromaticity coordinates (x, y) when the off voltage is applied are (0, 0) by adopting the panel configuration of this embodiment. .3
4, 0.32), which is closer to the D65 white light source (0.3127, 0.3291) and red (0.4
7, 0.28), blue (0.19, 0.19), and green (0.25, 0.50).

In this embodiment, the liquid crystal cell 6 has a twist angle of the liquid crystal molecules 4 of about 250 °, the liquid crystal layer has a Δn _LC · d _LC of 1.90 μm, and a single retardation plate 12.
Roh △ n _F · d _F is set to 1.966Myuemu, the liquid crystal cell 6 may be a liquid crystal molecule 4 is twisted by 200 ° to 270 ° twist angle of the liquid crystal layer △ n _LC · d _LC May be 1.2 μm to 2.2 μm, and the product Δn _F · d _F of the refractive index anisotropy Δn _{F of the} retardation plate and the plate thickness d _F is Δn _LC ·
d _LC + may be in the range of (0.05μm~0.15μm).

In the present embodiment, the front-side polarizing plate 1
Used a polarizing plate having a single hue of (a, b) ≒ (−0.7, −0.7). However, when off-voltage is applied, yellow with high luminous efficiency is suppressed and white with little coloring is suppressed. To obtain the display, the hue (Hunt) of the polarizing plate alone of the front-side polarizing plate is required.
er Lab color system, NBS unit), a is -2.0 to
It is desirable to use a front-side polarizing plate having +2.0 and b in the range of -8.0 to 0.0.

Further, in the present embodiment, polycarbonate is used for the uniaxially stretched retardation plate 12, but polyvinyl alcohol, polyarylate, polyether sulfone, or the like may be used.

In the present embodiment, in the arrangement of the front-side polarizing plate and the retardation plate, the slow axis of the adjacent retardation plate of the liquid crystal cell with respect to the liquid crystal molecule alignment direction on the substrate adjacent to the retardation plate of the liquid crystal cell. Although the shift angle is 92.5 °, it is preferable that the shift angle be 90 ° ± 10 °.

Further, the shift angle of the transmission axis of the front-side polarizing plate with respect to the slow axis of the phase difference plate adjacent to the front-side polarizing plate is 46.5.
However, it is desirable that the deviation angle be 45 ° ± 10 °.

Further, in the present embodiment, the shift angle between the transmission axis 11 of the rear-side polarizing plate and the liquid crystal molecule orientation direction 10 of the substrate adjacent to the rear-side polarizing plate is 45 °, but this shift angle is 4 °.
It is desirable to be 5 ± 10 °.

In this embodiment, the transmission type is a color liquid crystal display panel having a backlight. However, a reflection type color liquid crystal display panel may be provided by attaching a reflection plate outside the back side polarizing plate. . In the case of a reflective type color liquid crystal display panel, the deviation angle between the transmission axis 11 of the rear-side polarizing plate and the liquid crystal molecule orientation direction 10 of the polarizing plate adjacent substrate adjacent to the reflecting plate 16 is set to 45 ° ± 10 °. Is desirable.

In order to form a color liquid crystal display panel having a wider viewing angle, the birefringence when the panel is viewed from the front and the birefringence when the panel is viewed at an angle are provided on the uniaxially stretched retardation plate 12. It is desirable to use a three-dimensional refractive index controlled product that can reduce the difference in refraction.

(Embodiment 5) Hereinafter, an embodiment of the fifth invention will be described with reference to FIGS. 7, 8, and 11. FIG.

FIG. 7 is a sectional view of a color liquid crystal display panel according to the third and fifth embodiments of the present invention. This color liquid crystal display panel includes one liquid crystal cell 6 in which liquid crystal molecules 4 are twist-aligned, a pair of polarizing plates 1 and 5 arranged with the liquid crystal cell 6 interposed therebetween, and a liquid crystal cell 6 and a polarizing plate 1 on the front side. And two retardation plates 12 and 13 disposed between the two.

The liquid crystal cell 6 is of a simple matrix type. The electrodes 3 on the front transparent substrate 2 are a plurality of scanning electrodes formed in parallel with each other, and the electrodes 3 on the rear transparent substrate 2 are the scanning electrodes. An orientation film is applied on a plurality of signal electrodes formed in a direction perpendicular to the direction of the substrate, and a particle diameter of 8.0 μm
Was sprayed, and a sealant was printed on the periphery and then bonded. A trans nematic liquid crystal (Δn _LC = 0.2) having a chiral pitch of 13.3 μm was sealed after vacuum injection.

FIG. 8 shows the liquid crystal molecule alignment directions 9 and 10 of the liquid crystal cell 6, the slow axis directions 14 and 15 of the two polycarbonate uniaxially stretched retardation plates, and the transmission axis 8 of a pair of polarizing plates.
11 is a plan view of FIG. The angles between the liquid crystal molecule orientation direction 9 of the front side transparent substrate, the liquid crystal molecule orientation direction 10 of the back side transparent substrate and the reference line 7 are θ1 = 215 ° and θ2 = 145 °, and the liquid crystal molecules are oriented from the back side to the front side. 4 to almost 25
Twist orientation was performed at a twist angle of 0 °. The angle between the slow axis direction 14 of the uniaxially stretched retardation plate adjacent to the front-side polarizing plate 1 and the reference line 7 is { ₁ = 136}, Δn _F1 · d _F1 =
1.294 μm, and the angle between the slow axis direction 15 of the uniaxially stretched phase difference plate adjacent to the liquid crystal cell 6 and the reference line 7 is ψ2
= 124.5} and Δn _F2 · d _F2 = 0.392 μm. Transmission axis 8 of front side polarizing plate, transmission axis 1 of back side polarizing plate
The angle between 1 and the reference line 7 was {1 = 3} and {2 = 100}.

The hue (Hunter's Lab color system, NBS unit) of the polarizing plate alone is
NPF-F where (a, b) ≒ (−0.5, −1.0)
1225DU (manufactured by Nitto Denko Corporation) was used.

In the color liquid crystal display panel, the transmitted light is colored by the birefringence of the retardation plate, and the transmitted light is transmitted by the birefringence of the retardation plate and the birefringence of the liquid crystal in which the liquid crystal molecules are twisted. It is colored in another color.

When no voltage is applied between the electrodes of the liquid crystal cell, the light incident through one of the polarizing plates is changed by the birefringence of the twist-aligned liquid crystal molecules and the birefringence of the retardation plate. When the light is transmitted through the polarizing plate, the light becomes uncolored light.

When a voltage is applied between the electrodes of the liquid crystal cell, the birefringence in the liquid crystal cell changes in response to the change in the alignment state of the liquid crystal molecules. Therefore, coloring due to the birefringence of both the retardation plate and the liquid crystal cell. The color of the light changes.

Further, when a voltage is applied to cause the liquid crystal molecules to rise almost perpendicularly to the substrate surface, birefringence by the liquid crystal cell almost disappears, and the light transmitted through the other polarizing plate is reduced by the birefringence of the retardation plate. It becomes colored light only by.

The Δn _LC · d _LC of the liquid crystal layer was 1.6 μm.
m, 250} twist-oriented, and the sum of the product Δn _F · d _F of the refractive index anisotropy Δn _{F of the} retardation plate and the plate thickness d _F is 1.686.
In the case where the deviation of the slow axes of the two phase difference plates is 11.5 ° in μm, the linearly polarized light in which the light incident on one of the polarizers is almost equal to the light emitted from the other polarizer in the off-voltage applied state Therefore, a color closer to white can be displayed.

A backlight is installed on the color liquid crystal display panel having the above-described structure, and is driven with a voltage of (1/200) to (1/240) duty and (1/14) to (1/17) bias. It was controlled by the frame rate control method.

FIG. 11 is a CIE chromaticity diagram showing a color change of colored light when a voltage is applied. The CIE chromaticity coordinates (x, y) of a conventional color liquid crystal display panel (JP-A-6-308481) are white (0.36, 0.29), red (0.46, 0.39), blue (0, 0). .25, 0.2
2) and green (0.27, 0.47), but from FIG. 11, the CIE chromaticity coordinates (x, y) at the time of off-voltage application are (0, 0) by adopting the panel configuration of this embodiment. .3
4, 0.31), which is closer to the D65 white light source (0.3127, 0.3291) and red (0.5
6, 0.28), blue (0.16, 0.15), and green (0.21, 0.51).

In this embodiment, the liquid crystal cell 6 has a twist angle of the liquid crystal molecules 4 of about 250 °, the liquid crystal layer has a Δn _LC · d _LC of 1.60 μm, and the two retardation plates 1
Δn _F · d _F of 2, 13 is 0.392 μm, 1.294 μ
m, the liquid crystal cell 6 may have the liquid crystal molecules 4 twist-oriented at a twist angle of 200 ° to 270 °,
The Δn _LC · d _LC of the liquid crystal layer may be 1.2 μm to 2.2 μm, and the sum of the product Δn _F · d _F of the refractive index anisotropy Δn _{F of the} retardation plate and the plate thickness d _F. Is Δn _LC · d _LC + (0.05 μm ~
0.15 μm).

In the present embodiment, the front-side polarizing plate 1
Used a polarizing plate whose hue is (a, b) ≒ (−0.5, −1.0), but suppresses yellow with strong luminosity due to the application of off-voltage, and has little coloration. To obtain the display, the hue (Hunt) of the polarizing plate alone of the front-side polarizing plate is required.
er Lab color system, NBS unit), a is -2.0 to
It is desirable to use a front-side polarizing plate having +2.0 and b in the range of -8.0 to 0.0.

In this embodiment, polycarbonate is used for the uniaxially stretched retardation plates 12 and 13. However, polyvinyl alcohol, polyarylate, polyether sulfone, or the like may be used.

In the present embodiment, in the arrangement of the front-side polarizing plate and the retardation plate, the slow axis of the retardation plate adjacent to the liquid crystal cell with respect to the slow axis of the retardation plate adjacent to the front-side polarizing plate. Was set to 11.5 °, but this deviation angle was 30 °.
It is desirable to be within ゜.

Further, the shift angle of the slow axis of the adjacent retardation plate of the liquid crystal cell with respect to the liquid crystal molecule alignment direction on the side of the substrate adjacent to the retardation plate of the liquid crystal cell was 90.5 °. It is desirable to be 10 °.

Further, the shift angle of the transmission axis of the front-side polarizing plate with respect to the slow axis of the phase difference plate adjacent to the front-side polarizing plate was 47 °, and this shift angle was 45 ° ± 10 °. Is desirable.

Further, in the present embodiment, the shift angle between the transmission axis 11 of the rear-side polarizing plate and the liquid crystal molecule orientation direction 10 of the substrate adjacent to the rear-side polarizing plate is set to 45 °.
It is desirable to be 5 ± 10 °.

In the present embodiment, the color liquid crystal display panel is of a transmission type in which a backlight is provided. However, a reflection type color liquid crystal display panel may be formed by attaching a reflection plate outside the back side polarizing plate. . In the case of a reflective type color liquid crystal display panel, the deviation angle between the transmission axis 11 of the rear-side polarizing plate and the liquid crystal molecule orientation direction 10 of the polarizing plate adjacent substrate adjacent to the reflecting plate 16 is set to 45 ° ± 10 °. Is desirable.

In order to obtain a color liquid crystal display panel having a wider viewing angle, two uniaxially stretched retardation plates 12 and 13 are provided.
In addition, it is desirable to use a three-dimensional refractive index controlled product that can reduce the difference between the birefringence when the panel is viewed from the front and the birefringence when the panel is viewed at an angle.

[0137]

The color liquid crystal display device of the present invention does not use a color filter as in the conventional color liquid crystal display device, but uses only the birefringence of the liquid crystal layer or the birefringence of the uniaxially stretched retardation plate and the liquid crystal layer. The light is colored by the polarizing plate, a high transmittance is obtained, and the cost is reduced.

Further, by controlling the voltage applied to the liquid crystal cell, the color of the colored light can be changed, so that a plurality of colors can be displayed.

In the color liquid crystal display device according to the first aspect of the invention, the liquid crystal molecules are twisted at a twist angle of 100 ° to 270 °, and the Δn _LC · d _LC of the liquid crystal layer is set to 1.2 μm or less.
By setting the thickness to 2.2 μm, a color liquid crystal display panel that is close to white when no voltage is applied and has good red and blue color purity can be provided at low cost because no color filter is used.

Further, the hue (Hu
lab color system, NBS unit).
By setting 0 to +2.0 and b to be within the range of -8.0 to 0.0, yellow with higher luminosity is suppressed and a white display with less coloring is obtained.

The color purity can be improved by setting the shift angle between the transmission axis of the polarizing plate and the liquid crystal molecule alignment direction of each polarizing plate adjacent substrate to 45 ° ± 5 °.

Although the polarizing plate is directly disposed on the front side of the liquid crystal cell, a white display with less coloring is provided by disposing at least one retardation plate between the liquid crystal cell and the polarizing plate on the front side. Thus, the color purity of the color display can be improved.

When the retardation plate is provided, the slow axis of the retardation plate adjacent to the liquid crystal cell is shifted by 90 ° ± 10 ° with respect to the liquid crystal molecule alignment direction on the substrate adjacent to the retardation plate of the liquid crystal cell. A color liquid crystal display panel in which the color purity is further increased and the number of colors is increased by shifting the transmission axis of the front-side polarizing plate obliquely by 45 ° ± 10 ° with respect to the slow axis of the phase difference plate adjacent to the polarizing plate. Can be provided.

In the color liquid crystal display devices according to the second and third aspects of the present invention, the liquid crystal molecules are twisted at a twist angle of 200 ° to 270 °, and the Δn _LC · d _LC of the liquid crystal layer is 1.2 μm.
And ～2.2Myuemu, sum of products △ n _F · d _F of the refractive index anisotropy △ n _F and the plate thickness d _F of the retardation plate comprising at least one is _{△ n LC · d LC - (} 0. By setting the thickness in the range of 10 μm to 0.20 μm), a white display can be obtained when an off-voltage is applied, and a color liquid crystal display panel with increased color purity, increased number of colors, and reduced cost can be provided.

The hue (Hunter's Lab color system, NBS unit) of the polarizing plate alone of the front-side polarizing plate is such that a is -2.0 to +2.0 and b is -8.0 to 0.0. By setting the range, yellow with higher luminosity is suppressed and a white display with less coloring is obtained.

Further, in the color liquid crystal display devices according to the fourth and fifth aspects of the present invention, the liquid crystal molecules are twisted at a twist angle of 200 ° to 270 °, and the Δn _LC · d _LC of the liquid crystal layer is 1.2 μm to 2 μm. .2 μm, and the product of the refractive index anisotropy Δn _F and the plate thickness d _{F of} at least one retardation plate Δn _F.
The sum of d _F is Δn _LC · d _LC + (0.05 μm to 0.15
By setting the range to μm), a whiter display can be obtained when an off-voltage is applied, and a color liquid crystal display panel with increased color purity, increased number of colors, and reduced cost can be provided.

The hue (Hunter's Lab color system, NBS unit) of the polarizing plate alone of the front-side polarizing plate is such that a is -2.0 to +2.0 and b is -8.0 to 0.0. By setting the range, yellow with higher luminosity is suppressed and a white display with less coloring is obtained.

In the arrangement of at least two retardation plates used in the color liquid crystal display panel according to the third and fifth aspects of the present invention, the liquid crystal cell with respect to the slow axis of the retardation plate adjacent to the front-side polarizing plate is provided. By setting the shift angle of the slow axis of the adjacent retardation plate within 30 °, a color liquid crystal display panel with high color purity can be provided without a color filter.

In the arrangement of the front-side polarizing plate and the retardation plate used in the color liquid crystal display panel of the present invention, the retardation of the adjacent retardation plate of the liquid crystal cell with respect to the orientation direction of the liquid crystal molecules on the substrate adjacent to the retardation plate of the liquid crystal cell. 90 ° ±
It is desirable to be 10 °.

Further, the shift angle of the transmission axis of the front side polarizing plate with respect to the slow axis of the phase difference plate adjacent to the front side polarizing plate is set to 45 ° ±
By setting the angle to 10 °, a color liquid crystal display panel with high color purity can be provided without a color filter.

Further, by setting the angle of deviation between the liquid crystal molecule alignment direction of the back side polarizing plate used in the color liquid crystal display panel of the present invention and the substrate adjacent to the back side polarizing plate to 45 ° ± 10 °, the color purity is improved. A high color liquid crystal display panel can be provided without a color filter.

Further, a reflection type color liquid crystal display panel can be provided by attaching a reflection plate outside the back side polarizing plate used for the color liquid crystal display panel of the present invention.

Furthermore, the viewing angle dependence of the panel can be reduced by making the uniaxially stretched retardation plate used in the color liquid crystal display panel of the present invention a three-dimensional refractive index controlled product.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a color liquid crystal display device according to a first embodiment.

FIG. 2 is a plan view showing a liquid crystal molecule alignment direction of a liquid crystal cell and a transmission axis of a pair of polarizing plates in the color liquid crystal display device according to the first embodiment. (B) A diagram showing the liquid crystal molecule orientation direction of the front side transparent substrate and the liquid crystal molecule orientation direction of the back side transparent substrate.

FIG. 3 is a plan view showing a color change of colored light in the color liquid crystal display device of the first embodiment.

FIG. 4 is a sectional view of a color liquid crystal display device according to the second and fourth embodiments.

FIG. 5 shows the liquid crystal molecule alignment direction of the liquid crystal cell, the slow axes of two uniaxially stretched retardation plates, and the transmission axes of a pair of polarizing plates in the color liquid crystal display device according to the second and fourth embodiments. (A) A view showing a transmission axis of a front-side polarizing plate. (B) A view showing a slow axis of a retardation plate 1. (c) A liquid crystal molecule orientation direction of a front-side transparent substrate and a back-side transparent substrate. (D) A view showing the transmission axis of the back-side polarizing plate

FIG. 6 is a plan view showing a color change of colored light in a color liquid crystal display device according to a second embodiment.

FIG. 7 is a cross-sectional view of a color liquid crystal display device according to the third and fifth embodiments.

FIG. 8 shows the liquid crystal molecule alignment direction of the liquid crystal cell, the slow axes of two uniaxially stretched retardation plates, and the transmission axes of a pair of polarizing plates in the color liquid crystal display device according to the third and fifth embodiments. (A) a view showing the transmission axis of the front-side polarizing plate; (b) a view showing the slow axis of the phase difference plate 1; (c) a view showing the slow axis of the phase difference plate 2; The figure which shows the liquid crystal molecule orientation direction of a side transparent substrate, and the liquid crystal molecule orientation direction of a back side transparent substrate.

FIG. 9 is a plan view showing a color change of colored light in a color liquid crystal display device according to a third embodiment.

FIG. 10 is a plan view showing a color change of colored light in a color liquid crystal display device according to a fourth embodiment.

FIG. 11 is a plan view showing a color change of colored light in a color liquid crystal display device according to a fifth embodiment.

[Explanation of symbols]

 Reference Signs List 1 front side polarizing plate 2 transparent substrate 3 transparent electrode 4 liquid crystal molecule 5 back side polarizing plate 6 liquid crystal cell 7 reference line 8 transmission axis of front side polarizing plate 9 orientation direction of liquid crystal molecules of front side transparent substrate 10 liquid crystal of back side transparent substrate Molecular orientation direction 11 Transmission axis of back side polarizing plate 12 Phase difference plate 1 13 Phase difference plate 2 14 Slow axis of phase difference plate 1 15 Slow axis of phase difference plate 2 16 Reflection plate

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Hisanori Yamaguchi 1006 Kazuma Kadoma, Osaka Prefecture Matsushita Electric Industrial Co., Ltd.

Claims (13)

[Claims] 1. Two upper and lower sheets having transparent electrodes formed on opposing surfaces.
A liquid crystal is sandwiched between electrode substrates, and the molecules of the liquid crystal are
100 ° to 270 ° twist orientation between substrates,
Crystal anisotropy Δn_LCAnd a liquid crystal layer thickness d of the liquid crystal._LC(Μ
product with m) △ n _LC・ D_LCFrom 1.2 μm to 2.2 μm
Liquid crystal cell and two sheets of liquid crystal cell interposed therebetween.
A polarizing plate, wherein the transmission axis of the polarizing plate is
Of liquid crystal molecules on the substrate adjacent to the polarizer
45 ° ± 10 ° shifted obliquely, and the polarizing plate on the front side
Hue (Hunter's Lab color system, NBS unit)
a is in the range of -2.0 to +2.0, b is in the range of -8.0 to 0.0
And a color liquid crystal display panel. 2. The two upper and lower sheets having transparent electrodes formed on opposing surfaces.
A liquid crystal is sandwiched between electrode substrates, and the molecules of the liquid crystal are
100 ° to 270 ° twist orientation between substrates,
Crystal anisotropy Δn_LCAnd a liquid crystal layer thickness d of the liquid crystal._LC(Μ
product with m) △ n _LC・ D_LCFrom 1.2 μm to 2.2 μm
Liquid crystal cell and two sheets of liquid crystal cell interposed therebetween.
Polarizing plate, disposed between the liquid crystal cell and the front-side polarizing plate
And at least one retardation plate,
Hue of a polarizing plate alone (Hunter's Lab color system, N
BS unit), a is -2.0 to +2.0, b is -8.0
Color liquid crystal display characterized by being in the range of 0.0 to 0.0
panel. 3. An upper and lower two sheets having transparent electrodes formed on opposing surfaces.
A liquid crystal is sandwiched between electrode substrates, and the molecules of the liquid crystal are
200 ° to 270 ° twist alignment between substrates,
Crystal anisotropy Δn_LCAnd a liquid crystal layer thickness d of the liquid crystal._LC(Μ
product with m) △ n _LC・ D_LCFrom 1.2 μm to 2.2 μm
Liquid crystal cell and two sheets of liquid crystal cell interposed therebetween.
Polarizing plate, disposed between the liquid crystal cell and the front-side polarizing plate
Made of one retardation plate, and the refraction of the retardation plate
Rate anisotropy △ n_FAnd plate thickness d_FProduct △ n_F・ D_FIs △ n_LC・
d_LC− (0.10 μm to 0.20 μm).
Color liquid crystal display panel. 4. An upper and lower plate having transparent electrodes formed on opposing surfaces.
A liquid crystal is sandwiched between electrode substrates, and the molecules of the liquid crystal are
200 ° to 270 ° twist alignment between substrates,
Crystal anisotropy Δn_LCAnd a liquid crystal layer thickness d of the liquid crystal._LC(Μ
product with m) △ n _LC・ D_LCFrom 1.2 μm to 2.2 μm
Liquid crystal cell and two sheets of liquid crystal cell interposed therebetween.
Polarizing plate, disposed between the liquid crystal cell and the front-side polarizing plate
And at least two retardation plates,
Refractive index anisotropy of difference plate Δn_FAnd plate thickness d_FProduct △ n_F・ D_Fof
The sum is △ n_LC・ D_LC− (0.10 μm to 0.20 μm
m), a color liquid crystal display panel. 5. The arrangement of the retardation plate, wherein the slow axis of the retardation plate adjacent to the liquid crystal cell is shifted by 30 ° or less with respect to the slow axis of the retardation plate adjacent to the front-side polarizing plate. The color liquid crystal display panel according to claim 4, wherein: 6. An upper and lower two sheets having transparent electrodes formed on opposing surfaces.
A liquid crystal is sandwiched between electrode substrates, and the molecules of the liquid crystal are
200 ° to 270 ° twist alignment between substrates,
Crystal anisotropy Δn_LCAnd a liquid crystal layer thickness d of the liquid crystal._LC(Μ
product with m) △ n _LC・ D_LCFrom 1.2 μm to 2.2 μm
Liquid crystal cell and two sheets of liquid crystal cell interposed therebetween.
Polarizing plate, disposed between the liquid crystal cell and the front-side polarizing plate
Made of one retardation plate, and the refraction of the retardation plate
Rate anisotropy △ n_FAnd plate thickness d_FProduct △ n_F・ D_FIs △ n_LC・
d_LC+ (0.05 μm to 0.15 μm)
Color liquid crystal display panel. 7. An upper and lower two sheets having transparent electrodes formed on opposing surfaces.
A liquid crystal is sandwiched between electrode substrates, and the molecules of the liquid crystal are
200 ° to 270 ° twist alignment between substrates,
Crystal anisotropy Δn_LCAnd a liquid crystal layer thickness d of the liquid crystal._LC(Μ
product with m) △ n _LC・ D_LCFrom 1.2 μm to 2.2 μm
Liquid crystal cell and two sheets of liquid crystal cell interposed therebetween.
Polarizing plate, disposed between the liquid crystal cell and the front-side polarizing plate
And at least two retardation plates,
Refractive index anisotropy of difference plate Δn_FAnd plate thickness d_FProduct △ n_F・ D_Fof
The sum is △ n_LC・ D_LC+ (0.05 μm to 0.15 μ
m), a color liquid crystal display panel. 8. The arrangement of the retardation plate, wherein the slow axis of the retardation plate adjacent to the liquid crystal cell is shifted by 30 ° or less with respect to the slow axis of the retardation plate adjacent to the front-side polarizing plate. 8. The color liquid crystal display panel according to claim 7, wherein: 9. A single hue (Hunte) of the polarizing plate on the front side.
r is expressed by -2.0 to +
9. The color liquid crystal display panel according to claim 3, wherein 2.0 and b are in the range of -8.0 to 0.0. 10. The phase difference axis of the liquid crystal cell adjacent to the phase difference plate is shifted by 90 ° ± 10 ° with respect to the liquid crystal molecule alignment direction on the substrate side of the liquid crystal cell. 10. The transmission axis is shifted at an angle of 45. +-. 10.degree. With respect to a slow axis of a phase difference plate adjacent to the polarizing plate. Color liquid crystal display panel. 11. The liquid crystal cell according to claim 2, wherein the transmission axis of the back-side polarizing plate is shifted by 45 ° ± 10 ° with respect to the liquid crystal molecule alignment direction on the side of the liquid crystal cell adjacent to the polarizing plate. The color liquid crystal display panel according to 4, 5, 6, 7, 8, 9, or 10. 12. A three-dimensional refractive index controlled product is used as a retardation plate disposed between a liquid crystal cell and a front-side polarizing plate. , 8,9,1
The color liquid crystal display panel according to 0 or 11. 13. A polarizing plate according to claim 1, wherein a reflecting plate is provided outside the polarizing plate disposed on the back side.
3. The color liquid crystal display panel according to 3, 4, 5, 6, 7, 8, 9, 10, 11, or 12.