JPH09113937A - Liquid crystal display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain both low power consumption and excellent display characteristics by making a light source, provided on the back of a liquid crystal panel, has light emission characteristics of the chromaticity of a warm color system and compensating the color of a light source by the liquid crystal panel which has spectral transmissivity characteristics of the chromaticity of a cold color system. SOLUTION: This device consists of the liquid crystal panel which is equipped with a common electrode 1, a signal electrode 3, and a pixel electrode formed on at least one of a couple of substrates 7 and 7 and a liquid crystal layer sandwiched between the substrates, and the light source 30 which is provided on the back of the liquid crystal panel about an observer. Then the light source 30 has light emission characteristics of the chromaticity of a warm color and the liquid crystal panel has spectral transmissivity characteristics of the chromaticity of a cold color system and compensates the color of the light source 30. Here, the maximum value of the light transmission spectrum of the liquid crystal panel is preferably in a wavelength range of 400-520nm and when a voltage is applied to the liquid crystal panel, the product of the thickness of the liquid crystal layer which changes an orientation direction and the refractive index anisotropy of the liquid crystal is preferably <=0.26μm.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an active matrix type liquid crystal display device.

[0002]

2. Description of the Related Art As a method for making the direction of an electric field applied to a liquid crystal substantially parallel to the surface of a substrate, a method using a pair of comb electrodes is known.
For example, Japanese Examined Patent Publication No. 63-21907, USP4345249, WO91 / 109
No. 36, JP-A-6-222397 and the like. However, it is necessary to reduce the power consumption of the entire liquid crystal display device in a display system (hereinafter referred to as a lateral electric field system) in which the direction of the electric field applied to the liquid crystal is almost parallel to the substrate surface by using the active element. No mention is made of the characteristics of the light source.

[0003]

In the horizontal electric field system, an opaque electrode is provided in the display pixel portion in order to apply an electric field substantially parallel to the substrate surface. Therefore, compared with the conventional method of applying an electric field using a transparent electrode in a direction substantially perpendicular to the substrate surface (hereinafter referred to as the vertical electric field method), the aperture ratio is reduced and the brightness in a bright state is reduced. Because,
A high brightness light source is required.

On the other hand, since the effective display mode in the horizontal electric field type liquid crystal display device is the birefringence mode, the transmittance T is generally

[0005]

(Equation 1)

It is represented by Here, T ₀ is mainly determined by the transmittance of the polarizing plate, θ is the angle between the effective optical axis of the liquid crystal layer and the polarization transmission axis, d is the thickness of the liquid crystal layer, Δn is the refractive index anisotropy of the liquid crystal, λ represents the wavelength of light. Therefore, since the transmittance of the liquid crystal display element always has the maximum value at a certain wavelength, the liquid crystal display element is colored. One solution is to satisfy the condition that the peak wavelength is 555 nm, which is the maximum wavelength of visual sensitivity, that is, (πd · Δn / 555) = π / 2, in the zero-order retardation. However, at this time,
As shown in FIG. 2, the transmittance drops sharply on the short wavelength side of the peak wavelength and gradually decreases on the long wavelength side, so that the liquid crystal display element is colored yellow. From the above, a cold color system, which is a complementary color of yellow, that is, a characteristic having a high color temperature is required as a light source.

Generally, a fluorescent tube is used as a light source for a liquid crystal display device. As the characteristics of the phosphor, the luminous efficiency in the short wavelength region is inferior to that in the long wavelength region, so that the brightness of a fluorescent tube with a high color temperature decreases, and when trying to obtain high brightness, the power consumption becomes low. There is a problem that it will increase. In particular, in notebook type personal computers and portable information devices, increase in power consumption is a problem that must be avoided in order to enable long-term use with a battery.

An object of the present invention is to provide a liquid crystal display device which has both low power consumption and good display characteristics.

[0009]

A liquid crystal display device of the present invention has a pair of substrates, a plurality of electrodes formed on at least one of the pair of substrates, and a liquid crystal layer sandwiched between the pair of substrates. It is composed of a liquid crystal panel and a light source provided on the back of the liquid crystal panel for the observer, and the light source has a light emission characteristic of warm color chromaticity, and the liquid crystal panel has a cold color chromaticity. It has the following spectral transmittance characteristics and compensates for the color of the light source.

Here, the warm color system refers to a hue that gives a reddish color such as yellow or orange to "white" of the standard C light source, and the cold color system refers to that of the standard C light source. "White" refers to a hue that gives a blue tint. The light source of warm color has a low transmittance on the short wavelength side, and the liquid crystal panel of cold color has a low transmittance on the long wavelength side.By combining these, the light in the visible light region is transmitted almost uniformly, The standard LCD for the entire liquid crystal display
Try to approach the "white" light source.

The present invention makes it possible to reduce power consumption. The reason for this will be described below. Warm-color fluorescent lamps require less power consumption to obtain the same brightness as cold-color fluorescent lamps. Generally, assuming that the power consumption of a fluorescent lamp with a color temperature of 6000K is 1, the power consumption required to obtain the same brightness is 5% and 10000 with a fluorescent lamp of 8000K.
K increases by 10%, and 4000K decreases by 5%. For example, a liquid crystal display device colored in yellow has a color temperature higher than at least the color temperature 6770K of the standard C light source (white), and in order to compensate for the color, the light source is preferably 10,000K or more. There is a need. For example,
In the vertical electric field type liquid crystal display device, when the power consumption of 2W is required by using the fluorescent lamp of 8700K, in the configuration of the horizontal electric field type liquid crystal display device using the fluorescent lamp of color temperature 10000K, it is necessary for the light source. The power consumption is 2.06W, which is lower than the color temperature of C light source (white).
For fluorescent lamp of 000K, 1.87W is enough, 400
At 0K, the power consumption is 1.79W.

A warm color light source can be obtained by changing the type and mixing ratio of the phosphor. In the case of a narrow band luminescent type fluorescent lamp, the fluorescent lamp has an emission peak at 450 to 490 nm, and 3Ca ₃ (PO ₄ ) ₂ · Ca (F, Cl) ₂ : Sb ³ +,
_{Sr 10 (PO 4) 6 Cl} 2: Eu 2 +, (Sr, Ca) 10 (PO 4)
₆ Cl ₂ : Eu ² +, (Sr, Ca) ₁₀ (PO ₄ ) ₆ Cl ₂ · n
B ₂ O ₃ : Eu ² +, (Ba, Ca, Mg) ₁₀ (PO ₄ ) ₆ C
l ₂ : Eu ² +, Sr ₂ P ₂ O ₇ : Sn ² +, Ba ₂ P ₂ O ₇ : T
i ⁴ +, 2SrO 0.84P ₂ O ₅ 0.16B ₂ O ₃ : E
u ² +, MgWO ₄ , BaAl ₈ O ₁₃ : Eu ² +, BaMg ₂
Al ₁₆ O ₂₇ : Eu ² +, BaMg ₂ Al ₁₆ O ₂₇ : Eu ² + M
a phosphor such as n ² +, SrMgAl ₁₀ O ₁₇ : Eu ² +, 54
LaPO ₄ : C having an emission peak at 0 to 550 nm
e ³ +, Tb ³ +, LaO ₃ · 0.2SiO ₂ · 0.9P
₂ O ₅ : Ce ³ +, Tb ³ +, Y ₂ SiO ₅ : Ce ³ +, Tb ³ +
, CeMgAl ₁₁ O ₁₉ : Tb ³ +, GdMgB ₅ O ₁₀ :
Ce ³ +, Tb ³ + and other phosphors, and (Sr, Mg) ₃ (PO ₄ ) ₂ : Sn ² +, which has an emission peak near 610 nm,
CaSiO ₃ : Pb ² +, Mn ² +, Y ₂ O ₃ : Eu ³ +, Y
It is made by mixing phosphors such as (P, V) O ₄ : Eu ³ +.
It is possible to realize a fluorescent lamp having various color temperatures by controlling the relative intensity in each light emitting region by changing the mixing ratio of these. In order to obtain a warm-colored fluorescent lamp having a low color temperature, it is sufficient to increase the mixing ratio of the phosphors having an emission peak near 610 nm.

To realize a cold liquid crystal display panel,
There are the following three methods.

(1) In order to obtain a cold color characteristic, the maximum transmittance is set in the short wavelength region. Since the emission wavelength of the phosphor corresponding to green is 540 to 550 nm, and the emission wavelength corresponding to blue is 450 to 490 nm,
When the wavelength that maximizes the transmittance is 520 nm or less, the blue color tone can be strengthened, and a cold liquid crystal display device can be obtained. To do so, from equation (1), d · Δn is 0.2
It should be 6 or less. At this time, d indicates the thickness (d _eff ) of the liquid crystal layer that changes the orientation direction when a voltage is applied. The liquid crystal molecules in the vicinity of the interface of the liquid crystal layer do not change the orientation direction even when a voltage is applied due to the influence of anchoring of the interface. Let d _LC be the liquid crystal layer held by the substrate and d _eff be the liquid crystal layer that changes the orientation direction when a voltage is applied.
_eff <d _LC , and the difference is considered to be approximately 300 to 400 nm.

(2) The liquid crystal display panel has a birefringent film. The birefringent film has a peak wavelength of the light transmission spectrum of the liquid crystal display panel in the short wavelength region of visible light of 4
It is set so as to be in the range of 00 to 520 nm, preferably 440 to 490 nm.

(3) The thickness of the liquid crystal layer in the red display portion of the color filter is made thinner than d _{LC in the} blue and green portions.

Threshold voltage Ec of horizontal electric field type liquid crystal display device
Is

[0018]

(Equation 2)

## EQU1 ## Here, d _LC is the thickness of the liquid crystal layer, K ₂ is the elastic constant of the twist of the liquid crystal, Δε is the dielectric anisotropy of the liquid crystal, and ε ₀ is the dielectric constant of the vacuum. Therefore, d _LC
Becomes thinner, the threshold voltage shifts to the higher voltage side.
Therefore, by setting the thickness of the liquid crystal layer to be thin only in the pixel portion for displaying red, the voltage-transmittance characteristic in red, that is, the long wavelength region can be shifted to the high voltage side. Therefore, the transmittance in each voltage is suppressed in the long wavelength region, and the liquid crystal display element can have a large transmittance in the short wavelength region. The change in the thickness of the liquid crystal layer is preferably in the range of 0.1 to 1 μm in order to sufficiently suppress the transmittance in the long wavelength region and prevent the color balance from being excessively disturbed. For example, it is possible to make d _LC thin by making the red portion of the color filter thick. Further, the thickness of the liquid crystal layer of the portion to the display of the blue color filter red, may be thicker than d _LC of the green parts. Also in this case, the change in the thickness of the liquid crystal layer is preferably in the range of 0.1 to 1 μm.

In the case of a conventional TN (twisted nematic) type liquid crystal display device in which a vertical electric field is applied to a substrate (vertical electric field type), the degree of coloring is low and the liquid crystal panel is positively colored. I can't.

[0021]

BEST MODE FOR CARRYING OUT THE INVENTION FIG. 3 shows definitions of an angle Φp formed by a polarization transmission axis of a polarizing plate and an angle Φ _LC formed by a liquid crystal molecule long axis (optical axis) direction near an interface with respect to an electric field direction. Since there are a pair of the polarizing plate and the liquid crystal interface above and below, respectively, they are denoted as Φp ₁ , Φp ₂ , Φ _LC1 , and Φ _LC2 as necessary.

FIGS. 4A and 4B are side sectional views showing the operation of the liquid crystal in one pixel of the horizontal electric field type liquid crystal display element.
(C) and (d) show the front view. FIG. 4A is a sectional view of the element side when no voltage is applied, and FIG. 4C is a front view at that time.
Shown in The linear electrodes 1, 3, inside the pair of transparent substrates
4 is formed, and the orientation control film 5 is applied and oriented on it. A liquid crystal composition is sandwiched between them. The liquid crystal molecules 6 are 45 degrees <| Φ _LC | ≤ 90 when no electrolysis is applied.
Oriented to have degrees. The liquid crystal molecule alignment on the upper and lower interfaces will be described here by taking parallel, that is, Φ _LC1 = Φ _LC2 as an example. Further, the dielectric anisotropy of the liquid crystal composition is assumed to be positive. When an electric field 9 is applied, the liquid crystal molecules change their directions in the direction of the electric field as shown in FIGS. 4 (b) and 4 (d). By disposing the polarizing plate 8 on the polarizing plate transmission axis 11, the light transmittance can be changed by applying an electric field. In addition,
There is no problem even if the dielectric anisotropy of the liquid crystal composition is negative. In that case, the initial orientation state is oriented so that 0 ° <| Φ _LC | ≦ 45 °.

Two glass substrates having a thickness of 1.1 mm are used as the substrates. A thin film transistor is formed on one of these substrates, and an insulating film and an alignment film are further formed on the surface thereof. In this embodiment, polyimide is used as the alignment film and a rubbing process for aligning the liquid crystal is performed. Similarly, an alignment film is formed on the other substrate and a rubbing process is performed. The rubbing directions on the upper and lower interfaces are almost parallel to each other, and the angle with the direction of the applied electric field is 75 degrees (Φ _LC1
= Φ _LC2 = 75 degrees). The dielectric anisotropy between these substrates is positive, its value is 12.0, and the refractive index anisotropy is 0.
A nematic liquid crystal composition of 079 (589 nm, 20 ° C.) is filled. The cell gap d is a state in which spherical polymer beads are dispersed and sandwiched between the substrates, and liquid crystal is sealed therein.
54 μm. Therefore, d _LC · Δn is 0.28 μm, and d _eff · Δn is 0.24 μm. A pair of substrates is sandwiched between two polarizing plates, and the polarization axis of _one polarizing plate is Φp ₁
= 75 degrees and the other is Φp ₂ = −15 degrees.

FIG. 1 schematically shows the liquid crystal display device of the present invention. In the above liquid crystal display panel, as a light source, a light source 3 having a light emission characteristic shown in FIG.
A liquid crystal display device is produced by using an edge light type backlight unit including 0, a light guide 32, a diffusion plate 33, and a prism sheet 34.

When driving the liquid crystal display device, the power consumption required for the light source section is 1.8 W, and the spectral transmittance of this liquid crystal display panel when a drive voltage is applied is shown in FIG. 9 (a). The spectrum when used is shown in FIG. These chromaticity coordinates are shown in FIG. Although the liquid crystal display panel is of a cold color type, a good white balance can be obtained by combining it with a light source having a low color temperature.

Dielectric anisotropy is positive between the substrates and its value is 9.
0 and the refractive index anisotropy is 0.082 (589 nm, 2
A nematic liquid crystal composition at 0 ° C. is filled. The cell gap d is set to 3.8 μm. Therefore, d _LC · Δn is 0.3
1 μm, and d _eff · Δn is 0.28 μm. A liquid crystal display device is prepared by using an edge light type backlight unit using a cold cathode fluorescent lamp having a color temperature of 11000K and a light emission characteristic shown in FIG. 8B as a light source.
FIG. 11A shows the spectral transmittance of this liquid crystal display panel when a drive voltage is applied, and FIG. 11B shows the spectrum when this light source is used. These chromaticity coordinates are shown in FIG. When combining a yellowish liquid crystal display panel with a cold light source, the power consumption required for the light source is 2W
It is.

The light source is replaced with an edge light type backlight unit having a color temperature of 5885K. At this time, the power consumption required for the light source unit is 1.8W. The spectrum when this light source is used is shown in FIG. 13 (a), and the chromaticity coordinates are shown in FIG. 13 (b). The liquid crystal display device has a yellow color even when visually observed.

As shown in FIG. 6, a color filter 24 is provided on the substrate opposite to the substrate having the transistor element. Dielectric anisotropy is positive between substrates and its value is 7.3
And the refractive index anisotropy is 0.074 (589 nm, 20
Enclose the nematic liquid crystal composition (° C.). The cell gap d is 3.2 μm when spherical polymer beads are dispersed and sandwiched between the substrates and liquid crystal is enclosed. Therefore,
d · Δn is 0.24 μm. FIG. 14A shows the spectral transmittance characteristics of this liquid crystal display element when a voltage is applied, and FIG. 14B shows the chromaticity coordinates of a liquid crystal display device including a light source. The chromaticity coordinates of driving voltage application are located at the standard light source C. The power consumption required for the light source section is 1.8 W, and a horizontal electric field type liquid crystal display device having a good color display can be obtained.

Between the substrates, the dielectric anisotropy is positive and its value is 9.0, and the refractive index anisotropy is 0.082 (589 nm, 20).
Enclose the nematic liquid crystal composition (° C.). The cell gap d is 3.7 μm when spherical polymer beads are dispersed and sandwiched between the substrates and liquid crystal is enclosed. Therefore, d _LC · Δn is 0.30 μm and d _eff · Δn is approximately 0.27 μm. Between the upper substrate and the polarizing plate, it is made of polycarbonate and has a retardation of 595n.
The retardation film of m (550 nm) has a slow axis angle Φ _F1 parallel to the upper polarizing plate, that is, Φ _F1 = Φ p ₁
Stick it so that it is = 75 degrees. This liquid crystal display panel has a color temperature 4348 having the light emission characteristics shown in FIG.
An edge light type backlight unit using a cold cathode fluorescent lamp of K is used as a light source. FIG. 15 shows a locus on the chromaticity coordinates when the voltage of this liquid crystal display device is turned on. The locus of chromaticity coordinates approaches the C light source,
The power consumption required for the light source is 1.7W.

On the substrate 7 facing the substrate having the transistor elements, as shown in FIG. 6, stripe-shaped R,
The color filters 24 of G, B, and 3 colors are provided, a protective film 25 for flattening the surface is laminated on the color filters, and the alignment film 5 is formed thereon. Between the substrate and the polarizing plate, it is made of polycarbonate and has a retardation of 349n.
The retardation film of m (550 nm) has a slow axis angle Φ _F1 orthogonal to the upper polarizing plate, that is, Φ _F1 = Φ p ₂
Stick it so that it is -15 degrees. This liquid crystal display panel has a color temperature 470 having a light emission characteristic shown in FIG.
An edge light type backlight unit using a cold cathode fluorescent lamp of 3K is used as a light source. In this liquid crystal display device, the chromaticity coordinates when a drive voltage is applied are close to the C light source, and the power consumption required for the light source unit is 1.75W.

The film thickness of the color filter is about 2 μm for the B and G pixel portions, and about 2.5 μm for the R pixel portion. This difference remains as a step of about 0.3 μm even after applying the flattening film by spin coating,
The difference is the thickness of the liquid crystal layer. In this liquid crystal display panel, an edge light type backlight unit using a cold cathode fluorescent lamp having a color temperature of 4703K is used as a light source. The wavelengths of this liquid crystal display device are 615 nm, 545 nm and 465 nm.
FIG. 16 shows the voltage-transmittance characteristic in nm, that is, the voltage-transmittance characteristic corresponding to each R, G, B pixel. It can be seen that the transmittance characteristic of the R pixel is shifted to the high voltage side. Therefore, in the transmittance of the liquid crystal display panel when a drive voltage is applied, the characteristic is that red is suppressed.
The white balance is good when a drive voltage is applied, and the power consumption required for the light source unit is 1.75W.

The thickness of the color filter is about 2 μm for the G and R pixel portions and about 1.5 μm for the B pixel portion. The thickness of the liquid crystal layer is about 3.8 μm for the G and R pixel portions and about 4.1 μm for the B pixel portion. An edge light type backlight unit using a cold cathode fluorescent lamp having a color temperature of 4703K is used as a light source in this liquid crystal display element. FIG. 17 shows the voltage-transmittance characteristic of the liquid crystal display device at wavelengths of 615 nm, 545 nm, and 465 nm, that is, the voltage-transmittance characteristic corresponding to each of the R, G, and B pixels. It can be seen that the transmittance characteristics of the B pixel are shifted to the low voltage side. Therefore,
In the transmittance of the liquid crystal display element when a drive voltage is applied, blue has a characteristic of being amplified. The white balance was good when the drive voltage was applied, and the power consumption required for the light source section was 1.75 W.

The film thickness of the color filter is about 2 μm for the G pixel portion, about 1.5 μm for the B pixel portion, and about 2.5 μm for the R pixel portion. The thickness of the liquid crystal layer is about 4.2 μm for the G pixel portion, about 3.9 μm for the R pixel portion, and about 3.9 μm for the B pixel portion. An edge light type backlight unit using a cold cathode fluorescent lamp having a color temperature of 4348K is used as a light source in this liquid crystal display panel. The voltage at the wavelengths of 615 nm, 545 nm, and 465 nm of this liquid crystal display element
FIG. 18 shows the transmittance characteristics, that is, the voltage-transmittance characteristics corresponding to the R, G, and B pixels. It can be seen that the transmittance characteristic of the B pixel is shifted to the low voltage side, and the transmittance characteristic of the R pixel is shifted to the high voltage side. The white balance is good when the drive voltage is applied, and the power consumption required for the light source unit is 1.7W.

The film thickness of the color filter is about 2 μm for the G and R pixel portions and about 1.5 μm for the B pixel portion. The thickness of the liquid crystal layer is about 4.5 μm for the G and R pixel portions and about 4.2 μm for the B pixel portion. The phase difference film, the upper substrate polarizing plates, made with polycarbonate over sulfonates, retardation used as a 997nm (550nm), parallel angle [Phi _F1 of the slow axis and the upper polarizing plate, i.e. [Phi _F1 = Φp
Stick it so that ₁ = 75 degrees. An edge light type backlight unit using a cold cathode fluorescent lamp having a color temperature of 4348K is used as a light source in this liquid crystal display panel. FIG. 19 shows the locus on the chromaticity coordinate due to the voltage application. It can be seen that the light source approaches the C light source as the voltage is applied. The white balance is good when the drive voltage is applied, and the power consumption required for the light source unit is 1.70 W.

[0035]

A liquid crystal display device having low power consumption and good white balance can be provided.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing a configuration of a liquid crystal display device of the present invention.

FIG. 2 is a diagram showing a spectral transmittance characteristic of a horizontal electric field type liquid crystal display panel.

FIG. 3 is a diagram showing definitions of a rubbing direction and an axial direction of a polarizing plate.

FIG. 4 is a diagram showing an operation of a horizontal electric field type liquid crystal display device.

FIG. 5 is a diagram showing color temperature and chromaticity coordinates in UCS chromaticity coordinates.

FIG. 6 is a diagram showing a configuration of a color filter substrate.

FIG. 7 is a diagram showing emission characteristics of a light source.

FIG. 8 is a diagram showing light emission characteristics of a light source.

FIG. 9 shows spectral transmittance characteristics of a liquid crystal display panel and spectral characteristics of a liquid crystal display device.

FIG. 10 is a C light source of a liquid crystal display panel, a light source, and chromaticity coordinates when the liquid crystal display device is used.

FIG. 11 shows spectral transmittance characteristics of a liquid crystal display panel and spectral characteristics of a liquid crystal display device.

FIG. 12 shows chromaticity coordinates of a C light source of a liquid crystal display panel, a light source, and a liquid crystal display device.

FIG. 13: Spectral characteristics of liquid crystal display panel, C light source of liquid crystal display panel, light source, chromaticity coordinates of liquid crystal display device.

FIG. 14 shows spectral transmittance characteristics of a liquid crystal display panel and chromaticity coordinates of a C light source, a light source, and a liquid crystal display device of the liquid crystal display panel.

FIG. 15 is a locus on a chromaticity diagram associated with voltage application of a liquid crystal display device.

FIG. 16 is a diagram showing voltage-transmittance characteristics at three wavelengths of a liquid crystal display device.

FIG. 17 is a diagram showing voltage-transmittance characteristics at three wavelengths of a liquid crystal display device.

FIG. 18 is a diagram showing voltage-transmittance characteristics at three wavelengths of a liquid crystal display device.

FIG. 19 is a diagram showing a locus on a chromaticity diagram associated with voltage application of a liquid crystal display device.

[Explanation of symbols]

1 ... Common electrode, 2 ... Gate insulating film, 3 ... Signal electrode, 4 ...
Pixel electrodes, 5 ... Alignment film, 6 ... Liquid crystal molecules, 7 ... Substrate, 8 ...
Polarizing plate, 9 ... Electric field, 10 ... Rubbing direction, 11 ... Transmission axis of polarizing plate, 23 ... Active matrix liquid crystal display element, 24 ... Color filter, 25 ... Protective film, 27 ... Insulating film, 30 ... Light source, 31 ... Light cover, 32 ... light guide,
33 ... Diffusion plate, 34 ... Prism sheet.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Osamu Ito 7-1-1 Omika-cho, Hitachi-shi, Ibaraki Hitachi Ltd. Hitachi Research Laboratory (72) Inventor Masato Oe 3300, Hayano, Mobara-shi, Chiba Shares Hitachi, Ltd. Electronic Device Division (72) Inventor Kazuhiko Yanagawa 3300 Hayano, Mobara, Chiba Prefecture Hitachi Electronic Device Division (72) Inventor Keiichiro Ashizawa 3300 Hayano, Mobara, Chiba Hitachi Electronic Device Business Department

Claims (7)

[Claims] 1. A liquid crystal panel having a pair of substrates, a plurality of electrodes formed on at least one of the pair of substrates, and a liquid crystal layer sandwiched between the pair of substrates, and one of the liquid crystal panels. A liquid crystal display device having a light source provided on a surface, wherein the light source has an emission characteristic of warm color chromaticity, and the liquid crystal panel has a spectral transmittance of cold color chromaticity. A liquid crystal display device having characteristics and compensating for the color of the light source. 2. The liquid crystal display device according to claim 1, wherein the maximum value of the light transmission spectrum of the liquid crystal panel is 400.
A liquid crystal display device having a wavelength range of ˜520 nm. 3. The liquid crystal display device according to claim 1, wherein the thickness (d _eff ) of the liquid crystal layer that changes the alignment direction when a voltage is applied to the liquid crystal panel, and the refractive index anisotropy (Δn) of the liquid crystal. A liquid crystal display device having a product d _eff · Δn of 0.26 μm or less. 4. The liquid crystal display device according to claim 1, wherein a pair of polarizing plates are arranged inside the liquid crystal panel so as to sandwich the pair of substrates, and a pair of polarizing plates is arranged between the polarizing plate and the substrate. A liquid crystal display device comprising a refraction film. 5. The liquid crystal display device according to claim 1, wherein a color filter is provided on at least one of the pair of substrates, and a thickness of a liquid crystal layer at a portion for transmitting red light transmits green light. A liquid crystal display device characterized in that it is thinner than the thickness of the liquid crystal layer of the portion. 6. The liquid crystal display device according to claim 1, wherein a color filter is provided on at least one of the pair of substrates, and a thickness of a liquid crystal layer at a portion for transmitting blue light is such that green light is transmitted. A liquid crystal display device, characterized in that it is thicker than the liquid crystal layer of the portion. 7. The liquid crystal display device according to claim 1, wherein the electric field formed in the liquid crystal layer by the plurality of electrodes is:
A liquid crystal display device, which is substantially parallel to the pair of substrates.