JP2000098369A - Liquid crystal display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liq. crystal display device capable of easily exchanging a polarizing plate member. SOLUTION: This device 51 is constituted by arranging a LCD panel 52 between polarizing plate members 53 and 54 including a polarizer and the polarizing plate members 53 and 54 are independently arranged. Light from a light source lamp 55 is made incident on a light scattering plate 57 and the polarizing plate 54 directly or guided by a light transmission plate 56 and becomes a linearly polarized light. The same light is made incident on the LCD panel 52 arranged with space on the upper side of the polarizing plate member 54 and becomes an elliptically polarized light. The same light is made incident on the polarizing plate member 53 arranged on the LCD panel 52 and becomes a linearly polarized light. These members are covered by an upper and lower bezel 59 and 58. The polarizing plate members 53, 54 are constituted with a polarizer arranged between two transparent resin plates and further include a phase difference plate. The transparent resin plate is a non-axial resin plate having no property polarizing light. And an antidazzle processing is applied on a surface of the polarizing plate member 53 in a displaying face side.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to information equipment, AV
The present invention relates to a liquid crystal display device applied to (audio visual) devices and display devices such as advertising displays.

[0002]

2. Description of the Related Art FIG. 8 shows a prior art liquid crystal display device 1.
FIG. The liquid crystal display device 1 includes an illumination mechanism of a one-light type edge light system. Polarizing plate members 3 and 4 are attached to respective surfaces of an LCD (liquid crystal display) panel 2 constituting the liquid crystal display device 1. The LCD panel 2 is mounted on a mounting board 14 together with a TCP (tape carrier package) 15. A display member is configured including the LCD panel 2, the polarizing plate members 3 and 4, the mounting board 14, and the TCP 15.

On the side of the polarizing plate member 4 opposite to the display surface,
The lens 12, the light diffusion plate 7, the light guide plate 6, and the light reflection sheet 11 are arranged in this order. A light source lamp 5 is arranged on a side surface of the light guide plate 6, and light from the light source lamp 5 enters the LCD panel 2 directly or guided by the light guide plate 6. An illumination member is configured including the lens 12, the light diffusion plate 7, the light guide plate 6, the light reflection sheet 11, the light source lamp 5, and the lamp wiring 10, and these are arranged on the lower bezel 8, and Covered and fixed.

[0004] The display member is disposed above the illumination member fixed by the lower bezel 8 and the frame 13 via a buffer spacer 16, and the upper bezel 9 is further disposed. In this way, all components are covered and fixed by the lower bezel 8 and the upper bezel 9.

FIG. 9 is a cross-sectional view for explaining the polarizing plate member 3, and FIG. 9A is a cross-sectional view showing the polarizing plate member 3a before being attached to the LCD panel 2, and FIG. () Is a cross-sectional view showing a state in which it is attached. In the polarizing plate member 3a, protective layers 18 and 19 are provided on each surface of the polarizer 17, a protective sheet 20 is further provided on one protective layer 18, and an adhesive layer 21 is provided on the other protective layer 19 via an adhesive layer 21. Separator 2
2 is provided. When attaching to the LCD panel 2, the separator 22 is peeled off, and the exposed adhesive layer 21 and L
One side of the CD panel 2 is brought into contact with the surface of the substrate member 23. The polarizing plate member 4 is also configured in the same manner, and the adhesive layer 21 exposed by peeling the separator 22 and the LC
The surface of the other substrate member 24 constituting the D panel 2 is brought into contact.

[0006] The LCD panel 2 is basically constituted by sandwiching a liquid crystal layer 25 between one substrate member 23 and the other substrate member 24. One and other substrate members 23, 24
Is appropriately configured according to the type of the LCD panel 2, and generally includes a light-transmitting substrate and a display electrode provided on the liquid crystal layer side surface of the light-transmitting substrate. Further, a liquid crystal material constituting the liquid crystal layer 25 is appropriately selected according to the type of the LCD panel 2.

FIG. 10 is a cross-sectional view for explaining another polarizing plate member 3, and FIG. 10A is a cross-sectional view showing a polarizing plate member 3b before being attached to the LCD panel 2.
(B) is sectional drawing which shows the state which stuck. The polarizing plate member 3b is configured in substantially the same manner as the polarizing plate member 3a, except that the phase difference plate 26
And a separator 22 is provided on the phase difference plate 26 with an adhesive layer 27 interposed therebetween.

FIG. 11 is an exploded perspective view showing the liquid crystal display device 1. As described above, the LCD panel 2 and the polarizing plate member 3 are provided on the illumination member 29 including the lens 12, the light diffusion plate 7, the light guide plate 6, the light reflection sheet 11, the light source lamp 5, and the lamp wiring 10. , 4, mounting board 14
And a display member 28 including the TCP 15 and the upper bezel 9 are arranged to configure the liquid crystal display device 1.

FIG. 12 is a view for explaining the polarization function of the polarizer 17. As shown in FIG. The polarizing function of the polarizer 17 is to transmit only light that is perpendicular to the light traveling direction and vibrates strongly in a specific direction, and absorbs other light. The polarizing function of the polarizer 17 is such that, for example, a film made of PVA (polyvinyl alcohol) is stretched and immersed in a solution containing iodine or a dichroic dye to adsorb iodine molecules or dye molecules in the stretching axis direction of the film. It is obtained by dispersing and orienting. In FIG. 12, when light from a light source enters a polarizer 17 having a transmission axis (Y axis) and an absorption axis (Z axis) that is an extension axis, light vibrating in the absorption axis direction (extension axis direction) Light that is absorbed and vibrates in a direction perpendicular to the direction of the absorption axis is transmitted.

By attaching the polarizing plate members 3 and 4 to a TN (twisted nematic) type LCD panel 2 such that the transmission axes or absorption axes are orthogonal to each other, when no voltage is applied to the liquid crystal layer, On the other hand, light transmitted through the polarizing plate member passes through the other polarizing plate member, and a white display state is obtained. When a voltage is applied to the liquid crystal layer, light transmitted through one polarizing plate member is absorbed by the other polarizing plate member, and a black display state is obtained. Such a display method,
Generally, it is called an NW (normally white) system or a positive system. Conversely, the polarizer members 3 and 4 are set so that the transmission axis or the absorption axis is parallel to each other so that the TN type L
By sticking to the CD panel 2, a black display state occurs when no voltage is applied to the liquid crystal layer, and a white display state occurs when a voltage is applied to the liquid crystal layer.
(Normally black) method or negative method.

Regarding the polarizing plate members 3 and 4, the polarizer 17
Is obtained by adsorbing or dispersing iodine molecules and dye molecules on a PVA film as a base material as described above. The protective layers 18 and 19 are realized by acrylic resin or TAC (triacetyl cellulose) resin. Protective film 20
Is realized by a film of an acrylic resin or a TAC resin. Acrylic resin is used for the adhesive layers 21 and 27.

[0012]

When the liquid crystal display device 1 is used in a severe environment, the polarizing plate members 3 and 4 are deteriorated and need to be replaced. For that purpose, it is necessary to peel off the polarizing plate members 3 and 4 attached to the LCD panel 2 and to attach new polarizing plate members 3 and 4. On the other hand, when the size of the liquid crystal display device has been conventionally increased, the uniformity of the liquid crystal layer thickness of the LCD panel 2 and the warpage of the light-transmitting substrate constituting the substrate member of the LCD panel 2 greatly affect the display quality. Therefore, the display quality of the liquid crystal display device 1 is degraded by the stress applied to the LCD panel 2 when attaching new polarizing plate members 3 and 4. In addition, the polarizing plate member is deformed due to a change in environmental conditions after pasting, and stress is applied to the LCD panel 2,
The display quality of the liquid crystal display device 1 is reduced.

FIG. 13 is an exploded perspective view showing a liquid crystal display device 31 disclosed in Japanese Patent Application Laid-Open No. 1-164921. In the liquid crystal display device 31, the polarizing plate member can be replaced while keeping the display quality high. That is, the polarizing plate members 35 and 40 are attached not to the LCD panel 36 but to the light diffusion plate 34 and the parting plate 39. Specifically, the liquid crystal display device 1 has a light diffusion plate 34 on which a polarizing plate member 35 is attached and a parting plate on which a polarizing plate member 40 is attached, with the LCD panel 36 mounted on the mounting substrate 38 together with the TCP 37 interposed therebetween. 39 and an LCD of the light diffusion plate 34
The light source lamp 32 is disposed on the side opposite to the panel 36, and a light reflecting member 33 that reflects light from the lamp 32 toward the LCD panel 36 is provided.

However, the liquid crystal display device 3 shown in FIG.
In 1, the mechanism for attaching the polarizing plate members 35 and 40 to the light diffusion plate 34 and the parting plate 39 is required. Further, the light diffusion plate 34 and the parting plate 39 must have a structure that can withstand the deformation of the polarizing plate members 35 and 40. Further, the light diffusion plate 34 and the parting plate 39 to which the polarizing plate members 35 and 40 are attached
There are various types according to the type of liquid crystal display device. Therefore, the polarizing plate members 35 and 40 must be adhered to the various light diffusing plates 34 and the parting plate 39, and the versatility is poor, and the handling is complicated and difficult.

Further, when a polarizing plate member is attached to the LCD panel, if a defect due to the LCD panel occurs, L
It is necessary to replace not only the CD panel but also the polarizing plate member, which increases the cost required for replacement. This is the same even when the polarizing plate member is attached to a light diffusion plate or a parting plate.

Furthermore, when the polarizing plate member is attached to another member such as an LCD panel, dust and foreign matter are generated due to friction and contact involved in the work. If the generated dust or foreign matter adheres to a portion related to display, the display quality of the liquid crystal display device is deteriorated.

An object of the present invention is to provide a liquid crystal display device in which a polarizing plate member can be easily replaced.

[0018]

According to the present invention, in a liquid crystal display device having a liquid crystal display panel and at least one polarizing plate member including a polarizer, the polarizing plate members are independently arranged. Liquid crystal display device.

According to the present invention, since the polarizing plate members are independently disposed, when the polarizing plate members are deteriorated and need to be replaced, the influence on other members such as a liquid crystal display panel is taken into consideration. In addition, the polarizing plate member can be easily replaced. That is, since the polarizing plate member is not attached to the liquid crystal display panel, no stress is applied to the liquid crystal display panel, so that the uniformity of the liquid crystal layer thickness is not reduced and the light transmitting substrate is not warped. For this reason, the polarizing plate member can be replaced while maintaining the display quality of the liquid crystal display device high. Further, since there is no need to consider a mechanism for attaching the polarizing plate member to another member such as a liquid crystal display panel and the type thereof, it is excellent in versatility and easy to handle. In addition, when a defect caused by the liquid crystal display panel or other members occurs, only the part needs to be replaced,
The cost required for replacement is reduced. Furthermore, since the polarizing plate member is not attached to another member such as a liquid crystal display panel, there is no generation of dust or foreign matter, and a decrease in display quality of the liquid crystal display device can be prevented.

According to another aspect of the present invention, there is provided a liquid crystal display device for displaying an image by transmitting or blocking incident light, a light source, a light guide plate on which the light source is disposed on a side, and a light diffuser disposed on the light guide plate. A plate, a polarizing plate member including a polarizer disposed on the light diffusion plate, a liquid crystal display panel disposed above the polarizing plate member, and a polarizer including a polarizer disposed on the liquid crystal display panel. A liquid crystal display device comprising: a second polarizing plate member; and a housing that covers the light source, the light guide plate, the light diffusing plate, the polarizing plate member, the liquid crystal display panel, and the second polarizing plate member.

According to the present invention, the light from the light source is guided directly or by the light guide plate, is diffused by the light diffusion plate, passes through the polarizing plate member, and enters the liquid crystal display panel.
The incident light is controlled by the orientation of the liquid crystal molecules of the liquid crystal display panel, and is further transmitted through or absorbed by the second polarizing plate member. In this way, the display is performed by transmitting or blocking the incident light. Done. Each of these members described above is covered by a housing. In such a liquid crystal display device, the two polarizing plate members are configured independently of the other members. Therefore, the polarizing plate member can be easily replaced without considering the influence on other members such as the liquid crystal display panel. Thereby, the display quality of the liquid crystal display device can be kept high. In addition, the versatility of component replacement is excellent, handling is easy, and the cost required for replacement is reduced.

Further, the polarizing plate member of the present invention is characterized in that a polarizer is arranged between two transparent resin plates.

According to the present invention, the above-described polarizing plate member has a high mechanical strength because it is constituted by sandwiching a polarizer between two transparent resin plates serving as a base. It has excellent support and high impact resistance. Therefore, the polarizing plate member can be reliably provided independently of other members such as a liquid crystal display panel.

Further, the polarizing plate member of the present invention is characterized in that it further includes a retardation plate.

According to the present invention, the polarizing plate member including the above-mentioned retardation plate compensates for coloring caused by a phase difference of light generated in a liquid crystal layer of a liquid crystal display panel such as an STN (super twisted nematic) type. , It is possible to achromatic. Also, since the polarizer is sandwiched between two transparent resin plates serving as a base, it has high mechanical strength, excellent supportability of the polarizing plate member alone, and high impact resistance. Therefore, the polarizing plate member can be reliably provided independently of other members such as a liquid crystal display panel.

Further, the transparent resin plate of the present invention is characterized in that it is a non-axial transparent resin plate having no property of polarizing light.

According to the present invention, the transparent resin plate for maintaining the support of the polarizing plate member alone at a high level is realized by the above-mentioned resin plate, so that the polarizer can generate heat generated from a light source or the like. Can be prevented from being disturbed due to the influence of. In addition, since it is non-axial, the polarizing plate member can be further hardened and can be flattened.

Further, the present invention is characterized in that one of the two polarizing plate members disposed on the display surface side is subjected to anti-glare processing on the surface of the polarizing plate member.

According to the present invention, irregular reflection of external light on the display surface can be prevented by subjecting the polarizing plate member disposed on the display surface side to anti-glare processing. Therefore, the visibility of the display can be improved.

[0030]

FIG. 1 is a sectional view showing a liquid crystal display device 51 according to an embodiment of the present invention. The liquid crystal display device 51 includes an illumination mechanism of a one-light type edge light system. The liquid crystal display device 51 includes an LCD panel 52 and at least one (two in this embodiment) polarizing plate members 53 and 5.
The most characteristic feature is that the polarizing plate members 53 and 54 are independently arranged.

Light source lamp 5 constituting liquid crystal display device 51
5 is arranged on one side surface 56 a of the light guide plate 56. The light source lamp 55 is, for example, a linear cold-cathode tube, is arranged along the light guide plate side surface 56a, and the lamp wiring 60 is led out. The light guide plate 56 is realized by a transparent plastic made of an acrylic resin such as PMMA (polymethyl methacrylate) and a PC (polycarbonate) resin.

On one surface 56b of the light guide plate 56, light
A diffusion plate 57 is provided. The light diffusion plate 57 is, for example, transparent.
Light resin containing light diffusion material such as titanium oxide
A sheet of compound, or light spread on one or both sides
It is realized by a transparent sheet coated with paint containing
You. The other surface 5 opposing the one surface 56b of the light guide plate 56
A light reflection plate 61 is arranged on 6c. Light reflector 6
1 is, for example, TiO (Titanium oxide) and BaSO_Four 
(Barium sulfate) and other white pigments
Paint containing a reflective material such as glass beads
PET (polyethylene terephthalate) coated on one or both sides
(Rate) support sheet. Alternatively or
PET support sheet on which aluminum and silver are deposited
Is realized. The light reflecting plate 61 has a light diffusing property.
A gap between the light guide plate 56 and the other surface 56c.
It is preferable to arrange them.

On the light diffusion plate 57, a lens 62 is arranged. The lens 62 is, for example, a condenser lens. An illumination member is configured including the light source lamp 55, the lamp wiring 60, the light guide plate 56, the light diffusion plate 57, the light reflection plate 61, and the lens 62. The polarizing plate member 5 is provided on the lens 62.
4 are arranged. The polarizing plate member 54 is configured as described below. The illumination member and the polarizing plate member 54 described above are arranged on the lower bezel 58, and are covered and fixed by the frame 63. The frame 63 is formed of a heat-insulating resin such as an ABS (acrylonitrile-butadiene-styrene) resin at the periphery in the vicinity of the opening for display, and the other main body is formed of a resin such as a PC.

An LCD panel 52 is disposed above the polarizing plate member 54. Polarizing plate member 54 and LCD panel 52
And a gap is provided between them, and in this embodiment, about 0.8 m
m gaps are provided. The LCD panel 52 has a TCP 65
At the same time, it is mounted on the mounting substrate 64 and is arranged on the frame 63 via the buffer spacer 66. LCD panel 52
The polarizing plate member 53 is disposed on the substrate. Polarizing plate member 53
Is configured together with the polarizing plate member 54 as described later. An upper bezel 59 is arranged on the polarizing plate member 53. In this way, all the components are covered by the lower bezel 58 and the upper bezel 59, and the lower bezel 58 and the upper bezel 59 are joined and fixed.

FIG. 2 is a sectional view showing the polarizing plate member 53. The polarizing plate member 53 includes a protective layer 6 on each surface of the polarizer 67.
8 and 69, and an adhesive layer 70,
Transparent resin plates 71 and 74 are respectively provided via 73, and protective sheets 72 and 75 are further provided on the transparent resin plates 71 and 74.
Are provided respectively. The polarizing plate member 54 is similarly configured.

Regarding the polarizing plate members 53 and 54, the polarizer 6
Reference numeral 7 has a polarization function of transmitting only light that is perpendicular to the traveling direction of light and vibrates strongly in a specific direction, and absorbs other light. The polarizer 67 stretches a film made of, for example, PVA, immerses the film in a solution containing a dye having high durability against high temperature and high humidity such as iodine or a dichroic dye, and applies iodine molecules or dye molecules to the stretching axis of the film. It is created by adsorbing or dispersing and orienting in a direction.

The protective layers 68 and 69 are made of acrylic resin or TA.
It is realized by a resin having optical isotropy and high transparency such as C. The protective sheets 72 and 75 are made of acrylic resin or T
Implemented on AC sheets. For the adhesive layers 70 and 73, an acrylic resin having excellent transparency is used. The transparent resin plates 71 and 74 are realized by non-axial transparent resin plates having no property of polarizing light such as acrylic resin and PC. It is preferable not to use biaxial resin plates made of PET resin or the like as the transparent resin plates 71 and 74 because they disturb the polarization.

Since the polarizing plate members 53 and 54 have a structure in which the polarizer 67 is disposed between the transparent resin plates 71 and 74 serving as the base, they have high mechanical strength and excellent supportability by themselves. , With high impact resistance. Therefore, the LCD panel 5
2 and other members can be surely provided independently.

Further, when the product is transported as a product by the protective sheets 72 and 75, the transparent resin plate 71,
It is possible to prevent the surface of the base 74 from being scratched.
In addition, at the time of transport, the moisture resistance is high, antistatic
It is preferable to house in a container made of aluminum or the like.

Further, by realizing the transparent resin plates 71, 74 for maintaining the supportability of the polarizing plate members 53, 54 alone by using a resin plate having the above-described characteristics,
It is possible to prevent the polarizer 67 from being disturbed by the influence of heat generated from the light source lamp 55 and the like.
Further, since it is non-axial, the polarizing plate members 53 and 54 can be further hardened, and can be flattened.

The LCD panel 52 is basically configured by sandwiching a liquid crystal layer 78 between one substrate member 76 and the other substrate member 77. One and other substrate members 76, 77
Is appropriately configured according to the type of the LCD panel 52, and generally includes a light-transmitting substrate and a display electrode provided on the liquid crystal layer side surface of the light-transmitting substrate. The liquid crystal layer 7
The liquid crystal material constituting 8 is also appropriately selected according to the type of the LCD panel 52.

FIG. 3 is a sectional view showing another polarizing plate member 53. The polarizing plate member 53 is substantially the same as the polarizing plate member 53 of FIG. 2 except that a retardation plate 79 is provided on the protective layer 69 with an adhesive layer 73 interposed therebetween. A transparent resin plate 74 is provided with a layer 80 interposed therebetween.

FIG. 4 is an exploded perspective view showing the liquid crystal display device 51, and FIG. 5 is an overall perspective view. In addition,
FIG. 1 is a sectional view taken along line II of FIG. As described above, the polarizing plate member 54 and the LCD panel are provided on the illumination member 81 including the light source lamp 55, the lamp wiring 60, the light guide plate 56, the light diffusion plate 57, the light reflection plate 61, and the lens 62. 52 and a polarizing plate member 53 are arranged in this order, and further, an upper bezel 59 is arranged to configure the liquid crystal display device 51.

FIG. 6 is a diagram for explaining the principle of display on the liquid crystal display device 51. As shown in FIG. Here, the TN type L
An example of the NW method using the CD panel 52 and the polarizing plate members 53 and 54 not including the retardation plate shown in FIG. 2 will be described. In FIG. 6, the polarizers 6 of the polarizing plate members 53 and 54 are shown.
Only 7 is shown.

When light from a light source enters a polarizer 67 having a transmission axis and an absorption axis which is an extension axis, light vibrating in the absorption axis direction (extension axis direction) is absorbed, and is perpendicular to the absorption axis direction. Light that vibrates in different directions is transmitted. Two polarizers 6
7 is arranged so that the transmission axis or the absorption axis is orthogonal to each other and sandwiches the TN type LCD panel 52, so that when a voltage is not applied to the liquid crystal layer, light transmitted through the polarizer 67 is transmitted to the other side. Transmitted through the polarizer 67,
The display becomes white. When a voltage is applied to the liquid crystal layer, the light transmitted through one polarizer 67 is
And a black display state is obtained.

In the NB method, two polarizers 67 are arranged with the transmission axis or the absorption axis parallel to each other with the TN type LCD panel 52 interposed therebetween, and a voltage is applied to the liquid crystal layer. When there is no light, the light transmitted through one polarizer 67 is absorbed by the other polarizer 67, and a black display state is set. When a voltage is applied to the liquid crystal layer, light transmitted through one polarizer 67 transmits through the other polarizer 67, and a white display state is achieved.

FIG. 7 is a diagram for explaining another principle of display on the liquid crystal display device 51. In FIG. Here, STN
An example of the NB method using the LCD panel 52 of the mold type and the polarizing plate members 53 and 54 including the phase difference plate shown in FIG. 3 will be described. FIG. 7 shows only the polarizer 67 and the phase difference plate 79 of the polarizing plate members 53 and 54.

The two polarizers 67 are arranged such that their transmission axes or absorption axes are orthogonal to each other, so that the STN LC
It is arranged with the D panel 52 interposed. When no voltage is applied to the liquid crystal layer, the linearly polarized light transmitted through the polarizer 67 becomes elliptically polarized light by passing through the liquid crystal layer. This elliptically polarized light becomes linearly polarized light by the phase difference plate 79, is absorbed by the other polarizer 67, and becomes a black display state. When a voltage is applied to the liquid crystal layer, the linearly polarized light transmitted through the polarizer 67 becomes elliptically polarized light by passing through the liquid crystal layer. The elliptically polarized light is converted into elliptically polarized light close to linearly polarized light by the retardation plate 79, and is transmitted through the polarizer 67 to be in a white display state.

For example, in the case of the STN type liquid crystal display device 51, the light emitted from the light source lamp 55 is directly incident on the light diffusion plate 57, the lens 62 and the polarizing plate member 54. Alternatively, the light is incident on the light guide plate 56, and is repeatedly reflected, diffused, and totally reflected by the light reflection plate 61 provided on the surface 56 c of the light guide plate 56 and the emission end face of the light guide plate 56, and the light is reflected on the emission surface of the light guide plate 56. The light is guided to a certain surface 56 b and enters the light diffusion plate 57, the lens 62 and the polarizing plate member 54.

The light is converted to linearly polarized light by the polarizing plate member 54, and is emitted to the gap between the polarizing plate member 54 and the LCD panel 52, and the LCD panel 5 is left as it is without changing the polarization state.
2 is incident. In the liquid crystal layer, light is separated into ordinary rays and extraordinary rays, and linearly polarized light becomes elliptically polarized light. When a voltage is applied, a phase difference occurs between the ordinary ray and the extraordinary ray due to the birefringence effect, and an interference color (coloring) occurs due to the phase difference. LCD
The light emitted from the panel 52 enters the polarizing plate member 53, the phase difference is canceled by the polarizing plate member 53, and the light passes through the polarizing plate member 53 or is absorbed by the polarizing plate member 53.
In this way, the coloring caused by the phase difference is achromatic.

As described above, in the present embodiment, the polarizing plate members 53 and 54 are independently arranged to constitute the liquid crystal display device 51. Therefore, the polarizing plate members 53 and 54 are deteriorated and the necessity of replacement arises. Then, the polarizing plate members 53 and 54 can be easily replaced without considering the influence on other members such as the LCD panel 52.

For example, since the polarizing plate members 53 and 54 can be replaced without applying a stress to the LCD panel 52, the uniformity of the liquid crystal layer thickness can be maintained high, and the display quality of the liquid crystal display device 51 can be maintained high. be able to.

The other members such as the LCD panel 52, the light diffusing plate 57, and the lens 62 are provided with the polarizing plate member 5.
Since there is no need to consider the mechanism and the type for attaching 3, 54, it is excellent in versatility and easy to handle.

When a defect occurs in a member, only the member needs to be replaced, and the cost required for replacement is reduced.

Further, since the polarizing plate members 53 and 54 are not attached, there is no generation of dust and foreign matter, and the display quality of the liquid crystal display device 51 can be maintained high.

The polarizing plate member 5 arranged on the display surface side
It is preferable that the surface of 3 is subjected to anti-glare processing.
Thereby, irregular reflection of external light on the display surface can be prevented, and the visibility of display can be improved. The anti-glare processing can be performed by, for example, mixing silica as a light diffusing substance into an acrylic resin, and applying the mixture to a surface of the polarizing plate member 53, for example, a surface of a transparent resin plate with a thickness of 2 μm to 3 μm.

[0057]

As described above, according to the present invention, since the polarizing plate members are arranged independently, when the polarizing plate members are deteriorated and need to be replaced, the liquid crystal display panel or the like can be used. The polarizing plate member can be easily replaced without considering the influence on other members. Therefore, the display quality of the liquid crystal display device can be kept high, the versatility in replacing parts is excellent, the handling is easy, and the cost required for replacement is reduced.

According to the invention, the light from the light source is guided by the light guide plate, diffused by the light diffusion plate, incident on the liquid crystal display panel through the polarizing plate member, and transmitted through the second polarizing plate member. Alternatively, in a liquid crystal display device which is absorbed by the second polarizing plate member and transmits or blocks incident light in this manner to perform display, the two polarizing plate members are configured independently of other members. Therefore, the polarizing plate member can be easily replaced without considering the influence on other members such as the liquid crystal display panel.

Further, according to the present invention, since the polarizing plate member is constituted by sandwiching the polarizer by the transparent resin plate serving as the base,
The mechanical strength of the polarizing plate member is improved, and it has excellent supportability and high impact resistance. Therefore, the polarizing plate member can be reliably provided independently of other members such as a liquid crystal display panel.

Further, according to the present invention, the polarizing plate member including the retardation plate can compensate for the coloring caused by the phase difference of the light generated in the liquid crystal layer of the liquid crystal display panel of the STN type or the like, thereby achieving achromatic color. Since such a polarizing plate member is constituted by sandwiching a polarizer by a transparent resin plate serving as a base, the mechanical strength of the polarizing plate member is improved, and the polarizing plate member has excellent supportability and high impact resistance.

According to the present invention, since the transparent resin plate constituting the polarizing plate member is realized by a resin plate made of a non-polar resin having no polarizing property, the polarizer can reduce the heat generated by the light source or the like. It is possible to prevent the polarization property from being disturbed due to the influence. In addition, since it is non-axial, the polarizing plate member can be further hardened and can be flattened.

According to the present invention, since the anti-glare processing is performed on the polarizing plate member disposed on the display surface side, irregular reflection of external light on the display surface is prevented, and the visibility of the display is improved. be able to.

[Brief description of the drawings]

FIG. 1 shows a liquid crystal display device 51 according to an embodiment of the present invention.
FIG.

FIG. 2 is a cross-sectional view showing a polarizing plate member 53.

FIG. 3 is a sectional view showing another polarizing plate member 53;

FIG. 4 is an exploded perspective view showing the liquid crystal display device 51.

FIG. 5 is a perspective view showing the entire liquid crystal display device 51.

FIG. 6 is a diagram for explaining the principle of display in the liquid crystal display device 51.

FIG. 7 is a diagram for explaining another display principle in the liquid crystal display device 51.

FIG. 8 is a sectional view showing a liquid crystal display device 1 according to the prior art.

FIG. 9 is a cross-sectional view for explaining a polarizing plate member 3;
FIG. 9A is a cross-sectional view showing the polarizing plate member 3a before being attached to the LCD panel 2, and FIG. 9B is a cross-sectional view showing a state where the polarizing plate member 3a is attached.

FIG. 10 is a cross-sectional view for explaining another polarizing plate member 3, and FIG. 10 (A) is a cross-sectional view showing the polarizing plate member 3b before being attached to the LCD panel 2, and FIG. FIG. 3 is a cross-sectional view showing a state where it is attached.

FIG. 11 is an exploded perspective view showing the liquid crystal display device 1.

FIG. 12 is a diagram for explaining a polarization function of the polarizer 17;

FIG. 13 is an exploded perspective view showing a liquid crystal display device 31 disclosed in JP-A-1-164921.

[Explanation of symbols]

 Reference Signs List 51 liquid crystal display device 52 LCD (liquid crystal display) panel 53, 54 polarizing plate member 55 light source lamp 56 light guide plate 57 light diffusion plate 58 lower bezel 59 upper bezel 63 frame 67 light polarizer 68, 69 protective layer 70, 73, 80 Adhesive layer 71, 74 Transparent resin plate 72, 75 Protective film 76, 77 Substrate member 78 Liquid crystal layer 79 Retardation plate

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Claims (6)

[Claims] 1. A liquid crystal display device comprising a liquid crystal display panel and at least one polarizing plate member including a polarizer, wherein the polarizing plate members are independently arranged. 2. A liquid crystal display device that performs display by transmitting or blocking incident light, comprising: a light source; a light guide plate on which the light source is disposed on a side; a light diffusion plate disposed on the light guide plate; A polarizing plate member including a polarizer disposed on the light diffusion plate; a liquid crystal display panel disposed above the polarizing plate member; and a second polarization including a polarizer disposed on the liquid crystal display panel. A liquid crystal display device comprising: a plate member; and a housing that covers the light source, the light guide plate, the light diffusion plate, the polarizing plate member, the liquid crystal display panel, and the second polarizing plate member. 3. The liquid crystal display device according to claim 1, wherein the polarizing plate member is configured by disposing a polarizer between two transparent resin plates. 4. The liquid crystal display device according to claim 1, wherein the polarizing plate member further includes a retardation plate. 5. The liquid crystal display device according to claim 3, wherein the transparent resin plate is a non-axial transparent resin plate having no property of polarizing light. 6. The anti-glare treatment on one of the two polarizing plate members disposed on the display surface side, wherein a surface of the polarizing plate member is subjected to anti-glare processing.
The liquid crystal display device as described in the above.