TW200405042A - Laminated polarizing film, polarizing light source device and liquid crystal display device - Google Patents

Abstract

In a liquid crystal display device or the like, a system with enhanced circular polarizing light is utilized to ensure the circular polarization under necessary wavelength of visual light domain and increase the transformation efficiency for the polarizing light, thereby increasing the brightness enhancement achieved by the reflective polarizing film. There is provided a laminated polarizing film 10 formed by a reflective line polarizing film 21, and at least one laminated layer implemented by low-wavelength scattered phase-difference film 22 or reverse-wavelength scattered phase-difference film. On the side of reflective line polarizing film 21, an absorbing type polarizing film 20 can be laminated. In addition, at any position of the layer structure, a light diffusing layer 26 can be laminated. There is also provided a polarizing light source device 64 which sequentially disposes light source members including light guiding plates 52 and reflective plates 53 on the phase-difference film 22 of the laminated polarizing film 1. Furthermore, there is provided a liquid crystal display device which disposes a liquid crystal unit 30 and an absorbing polarizing film 41 on the side of the laminated polarizing film 10. In addition, there is provided a laminated polarizing film 41 capable of increasing indoor brightness and outdoor visibility. Furthermore, there is provided a polarizing light source device using the laminated polarizing film, which has excellent visibility, and a liquid crystal display device. Furthermore, there are provided a absorbing type polarizing film 20 and a reflective line polarizing film 21 implemented laminated layer, and the polarizing penetration axes of the two are substantially parallel. On the side of the reflective line polarizing film 21, a laminated polarizing film 100 formed by a phase-difference layer 123 having positive two-axis alignment is laminated, and a light diffusing layer 24 can be laminated at any position. The light source members including the light guiding plates 52 and reflective plates 53 are arranged on the side of the phase-difference layer 123 of the laminated polarizing film 10 to construct a polarizing light source device. Moreover, the liquid crystal unit 30 and a front side absorbing type polarizing film 41 are arranged on the side of the laminated polarizing film 10 to construct a liquid crystal display device 65.

Description

200405042 (1) 发明. Description of the invention [Technical field to which the invention belongs] The present invention relates to a transmissive liquid crystal display device, a light source device suitable for the liquid crystal display device, and a laminated polarizing film. Specifically, the present invention relates to a laminated polarizing film for the purpose of improving the effect of increasing the brightness by a reflective polarizing film, a polarized light source device using the same, and a liquid crystal display device. Moreover, in a transmissive liquid crystal display device, the external light reaching the backlight device can be efficiently emitted from the liquid crystal display device again, which can improve the shell of the screen, and the external light such as outdoor sunlight is strong. A laminated polarizing film that does not reduce the visibility of the screen under polarized environments, and a polarized light source device and a transmissive liquid crystal display device using the same. [Prior art]

Liquid crystal display devices are used in various fields due to their small size and light weight. The liquid crystal molecules in the liquid crystal display device are not used as light-emitting substances such as cathode ray tubes (CRT), but only serve as light valves for controlling the polarization state of light. Therefore, if no method is used for illumination, At this time, the liquid crystal display portion will be invisible. Here, a transmissive liquid crystal display device is a light source device arranged on the back of the liquid crystal display section. This conventional liquid crystal display device will be described with reference to FIG. 9. The liquid crystal display device generally controls the polarization state of light passing therethrough by electrically changing the alignment state of liquid crystal molecules enclosed in the liquid crystal cell 30. The liquid crystal cell 30 is a pair of opposite The transparent electrode, that is, the back-side transparent electrode 31 and the front-side transparent electrode 3 2 and the liquid crystal layer 3 3 held between them (2) (2) 200405042. Although not shown in the figure, the liquid crystal cell 30 includes a cell substrate disposed on the two outermost surfaces, and an alignment film for aligning the liquid crystal layer 3 to 3, and a color filter layer for color display. On the front of the liquid crystal cell 30, a front-side absorption-type polarizing film 41 for detecting a polarization state of light transmitted therethrough is disposed, and an optical element such as a retardation film 42 is disposed. On the other hand, a polarized light source device 91 that emits only a specific polarized light toward the liquid crystal cell 30 is disposed on the back of the liquid crystal cell 30 through a retardation film (not shown) on the back side as necessary. The polarized light source device 91 is provided with an absorption-type polarizing film 20 at a position facing the liquid crystal cell 30, and a light source device 61 is provided on the back surface thereof as necessary. The light source device 61 is composed of a light guide plate 52 having a light source 51 on the side or below, and a reflective plate 5 3 behind the light guide plate 52. When the light source 51 is arranged on the side, the light from here is In fact, all the reflections from the reflecting mirror 54 are guided to the light guide plate 52, and further, they are emitted toward the side of the absorption-type polarizing film 25. The transmission-type liquid crystal display device 90 is configured in the above-described manner. In recent years, a brightness enhancement system has been adopted in which a reflective polarizing film is interposed between a back-side absorbing polarizing film and a light source device. This brightness enhancement system is described in, for example, Japanese Patent Publication No. 9-5 1 1 844. Among the emitted light from the light source device, the back side is previously absorbed by the reflective polarizing film and the polarizing film is absorbed by the polarizing film. The polarized light component is reflected in advance and returned to the light source device. It can be reused, and the brightness of the display device can be increased by increasing the amount of light that can be used. With this brightness enhancement system, the transmission brightness can be increased without increasing the power consumption (3) 200405042. On the contrary, the power consumption can be reduced while maintaining the transmission brightness.

This brightness-enhancing system can more efficiently convert the polarizing component returned to the light source device into a polarizing component that is transmitted through the back-side absorption-type polarizing film by the reflective polarizing film, but it is more important to increase the brightness improving rate. As a method for increasing the brightness improvement rate, as proposed in Japanese Patent Laid-Open No. 200 1-1 473 2 1, the optical axes of the reflective polarizing film and the retardation film can be set at 4 5 ° or 1 3 5 °. A method of using a 1 / 4-wavelength retardation film as a retardation film to arrange them alternately. According to this method, since the brightness enhancement system uses circularly polarized light, it can effectively perform polarization conversion, and can improve the brightness improvement effect.

In order to make effective use of this idea, it is desirable that circular polarization can be used in the entire field of visible light. However, a retardation film extended from a normal polycarbonate resin has a characteristic that the retardation becomes larger with respect to a short wavelength. Therefore, a single retardation film cannot satisfy circular polarization in the entire field of visible light. , Because the effect of improving the brightness cannot be achieved by circularly polarized light. On the other hand, transmissive liquid crystal display devices are widely used in liquid crystal displays, liquid crystal televisions, cameras, and portable information terminals of notebook personal computers or desktop personal computers, which are not used indoors. There are any particular problems, but when used outdoors, especially under sunlight, most of the visibility is significantly reduced. This is because the sunlight is mainly reflected on the outermost surface of the liquid crystal display device and cannot pass through the liquid crystal display portion. In order to improve this phenomenon, it is considered to implement a countermeasure to increase the number of pixels, aperture, and the like by performing a non-reflection treatment on the outermost surface of the -8- (4) 200405042 liquid crystal display device. In this way, the sunlight will once reach the light source device 6 1 disposed on the back side of the transmissive liquid crystal display device as shown in FIG. 9, and will be reflected again by the reflection plate 53 which is incorporated here, and the like, and will again be reflected. The light emitted to the outside is used as illumination light of the liquid crystal display section.

At this time, sunlight enters the light source device 61 through the back-side absorption type polarizing film 40 and is reflected by the light source device 61, and then enters the back-side absorption type polarizing film 40 again. Therefore, if the polarization state is not changed during this period, since there is no unnecessary polarized light that is absorbed when it is incident again on the back-side absorbing polarizing film 40, it is possible to efficiently use sunlight, thereby improving the Visibility under the sun. In an actual liquid crystal display device, since a material such as a diffusion sheet 55 or a lens sheet 56 is used to change the polarization state, the utilization efficiency of sunlight is slightly lowered. Here, if a reflective polarizing film is arranged, the above-mentioned brightness enhancement system can be made effective, and the utilization efficiency of sunlight can be improved.

However, when a transmissive liquid crystal display device in which a retardation film is laminated on a reflective linear polarizing film can be effectively increased in the room can be used to increase the effect of improving the brightness, the visibility outside the room will be reduced. Although the reason is still unknown, the following situations can be considered. That is, in order to use sunlight, it is best not to change the polarization state when the sunlight is passed through the back-side absorbing polarizing film and reflected by the light source device and re-enters the back-side absorbing polarizing film. In the case where a retardation film is laminated, when it is incident on the back-side absorbing polarizing film again, its polarization state is switched. In an ideal state, it becomes -9-(5) 200405042. All the light is reflected. The polarized light will be reflected again by the light source device, and it will have to be reciprocated once more. Here, it is necessary to make a double reciprocation of multiples when the retardation film is not used between the reflective linear polarizing film and the light source device. Therefore, in the process, the utilization efficiency of light is reduced due to factors such as dissipation. .

As described above, if a retardation film is used for the purpose of increasing the brightness improvement indoors, there is a problem that the visibility outdoors is reduced. Therefore, for applications such as notebook personal computers and desktop personal computer liquid crystal displays that are mainly used indoors, although a laminated body using a reflective linear polarizing film and a retardation film can be effective, For a liquid crystal display device, such as a mobile phone or a portable information terminal, that can be used indoors and outdoors, when a multilayer of a reflective linear polarizing film and a retardation film is used, although a bright Picture, but the problem of darkening the picture outside the house.

[Summary of the Invention] (Problems to be Solved by the Present Invention) Here, the object of the present invention is to improve the polarization conversion at the necessary wavelength in the visible light field by ensuring the circular polarization at the necessary wavelength in the field of improving the brightness of the circular polarization By this, it is possible to increase the brightness improvement rate achieved by the reflective polarizing film. Furthermore, another object of the present invention is to provide a liquid crystal display device in which a reflective polarizing film has been arranged, while maintaining the effect of increasing the transmission brightness by laminating a retardation layer, while maintaining the brightness outside the house. -10- (6) 200405042 The utilization efficiency of sunlight can ensure good visibility both inside and outside the house. More specifically, a laminated polarizing film capable of improving brightness indoors and improving visibility outdoors is provided, and a polarized light source device and a liquid crystal display device using the polarized light source device are provided. (Means for solving problems)

The present inventors have found that by specifying the wavelength dispersion characteristics of the retardation film, the brightness improvement effect when using circularly polarized light can be further improved, and the brightness improvement rate can be improved.

Furthermore, the present inventors have discovered that by using a laminated polarizing film that is laminated in the order of an absorptive polarizing film, a reflective polarizing film, and a retardation layer, the brightness improving system is provided by providing the retardation layer with a positive biaxiality. Alignment can maintain the transmission brightness improvement effect at a high level while suppressing the reduction of the reflection intensity improvement effect, and can also improve the overall brightness of the combination of transmission brightness and reflection brightness. The term "transmittance brightness" herein refers to the brightness of a polarized light source device and a liquid crystal display screen illuminated by light emitted from a light source in the liquid crystal display device. The reflection brightness refers to the brightness of a polarized light source device and a liquid crystal display screen illuminated by light incident from an external environment located outside the liquid crystal display device. That is, according to the present invention, an absorptive polarizing film and a reflective linearly polarizing film are provided to be laminated so that the polarization transmission axes of the two become substantially parallel, and further, a low wavelength is laminated on the side of the reflective linearly polarizing film. At least one of a dispersion retardation film and an inverse wavelength dispersion retardation film, -11-(7) 200405042, or a retardation layer having positive biaxial alignment. The low-wavelength dispersion retardation film or reverse wavelength retardation film used here is preferably one having a retardation of 1/4 wavelength. In addition, the optical axis of the 1/4 wavelength retardation film and the polarization transmission axis of the reflective linear polarizing film are preferably laminated or intersected at an angle of approximately 45 °.

A retardation layer having positive biaxial alignment is preferably a 1/4 wavelength retardation layer. At this time, the polarization transmission axis of the reflective polarizing film and the optical axis of the 1/4 wavelength retardation layer having positive biaxial alignment are preferably laminated or crossed at approximately 45 ° or 135 °. It is preferable that the 1/4 wavelength retardation layer having positive biaxial alignment is formed by one biaxially stretched film, or laminated by at least two retardation films with different optical axes. The latter retardation film uses a uniaxially stretched film.

In order to impart light diffusibility to these laminated polarizing films, at least one of the laminated polarizing films may be provided with a light diffusion layer having an in-plane retardation 値 of 3 nm or less at any one position. This light-diffusion layer may have adhesiveness. In order to easily handle the laminated polarizing film of the present invention, and to avoid unnecessary interface reflection, it is preferable that at least one pair of adjacent films or layers be tightly laminated with a pressure-sensitive adhesive. Furthermore, according to the present invention, there is provided a polarized light source device including a laminated polarizing film, a light source member, and a reflecting plate, and the light source device and the reflecting plate are sequentially arranged on the retardation film side of the laminated polarizing film. . Furthermore, according to the present invention, there is provided a polarizing light source device, a liquid crystal cell, and a front-side absorption-type polarizing film.

-12- (8) 200405042 and front-side absorptive polarizing film are liquid crystal display devices that are sequentially arranged on the laminated polarizing film side of the polarizing light source device. Here, a light diffusion layer may be laminated between the liquid crystal cell and the front-side absorption-type polarizing film. In addition, it is preferable that at least one pair of adjacent members of each member from the laminated polarizing film to the front-side absorption type polarizing film is tightly laminated with a pressure-sensitive adhesive. [Embodiment]

In order to clarify the present invention, the drawings will be described in detail below with reference to specific drawings. The laminated polarizing film 10 of the present invention, as shown in the schematic cross-sectional view of FIG. 1, is a laminated polarizing film 20 and a reflective linear polarizing film 21, and at least the reflective linear polarizing film side One laminated low-wavelength retardation retardation film 2 2 or reverse wavelength-dispersion retardation film 23. Fig. 1 (a) shows an example in which the reflective linear polarizing film 2 1 and the low-wavelength dispersion retardation film 2 2 are laminated, and in (b), the reflective linear polarizing film 2 1 and the inverse are shown. An example of laminating a wavelength-dispersed retardation film. The reflection type linear polarizing film 21 is one that transmits linearly polarized light in a specific vibration direction and reflects linearly polarized light in a direction orthogonal thereto. The so-called polarized light transmission axis of a reflective linear polarizing film refers to a direction in which the transmittance of the linearly polarized light having a specific vibration direction from the perpendicular direction of the polarized film becomes the largest, and the so-called polarized reflection axis refers to a direction orthogonal to the polarized light. . The reflective linear polarizing film may be, for example, a -13- (9) 200405042 using a difference in reflectance of a polarized component caused by a Brewster (angle) angle.

A reflective linear polarizing film (for example, described in Japanese Patent Publication No. 6-5 08449) is a reflective linear polarizing film (for example, described in Japanese Patent Application Laid-Open No. 2-3 0 8 1 0) having a fine metal linear pattern. In the 6th publication), at least two kinds of polymer films are laminated, and a reflective linear polarizing film using anisotropy of reflectance due to refractive index anisotropy (for example, described in Japanese Patent Publication No. 9-506837) In the bulletin), a reflective linear polarizing film having a sea-island structure formed of at least two types of polymers in a polymer film and utilizing anisotropy of reflectance due to refractive index anisotropy (eg, described in (U.S. Patent No. 5,825,543), a reflective linear polarizing film in which particles are dispersed in a polymer film and an anisotropy of reflectance due to refractive index anisotropy is used (for example, described in Special Table Hei ii) -5 0 9 0 1)), the inorganic particles are dispersed in the polymer film, and the anisotropy of the reflectance caused by the difference in scattering power caused by the particle size is used. Reflection type linear polarizing film (disclosed in Japanese Patent Publication 9 - Publication No. 297,204 persons) and the like.

Although the thickness of the reflective linear polarizing film is not particularly limited, from the viewpoint of thinning the liquid crystal display device, the thinner the better. Specifically, it is preferably 1 mm or less, and more preferably 0.2 mm or less. Here, in order to reduce the thickness, at least two types of polymer films are laminated, and IJ is a reflective linear polarizing film with anisotropic reflectance caused by refractive index anisotropy, or a polymer film. It has a sea-island structure composed of at least two types of polymers, and uses a reflective linear polarizing film using anisotropy of reflectance due to refractive index anisotropy, or a selective reflection characteristic using a cholesteric cystal The reflective linear polarizing film -14-(10) 200405042 is particularly suitable for reducing the thickness of the laminated polarizing film of the present invention.

The so-called low-wavelength dispersion retardation film is a retardation film having a small retardation and a small dependence on wavelength. In the present invention, the phase difference R (λ 2) in the wavelength λ 2 selected from the wavelength range of 4 0 to 4 9 0 rim is selected from the wavelength range of 7 5 0 to 7 6 Onm. A λR (λ 2) / R (λ!) divided by the phase difference R (λ!) in λ! is in the range of 0.95 or more and 1.0 5 or less as a low-wavelength dispersion retardation film. This low-wavelength dispersive retardation film is, for example, a retardation film composed of an original norbornene-based resin. Specifically, a film extended from the brand name "ARTON" (resin manufactured by JSR Corporation), or Trade name "S-Sheet" (phase retardation film manufactured by Sekisui Chemical Industry Co., Ltd.), etc. The so-called inverse wavelength dispersion retardation film 23 is, for example, Proceedings of The Seventh International Display Workshops (2000) proposed by Uclnyama and Yatabe. ) 'p407 — 410

As reported, it is a retardation film having a small phase difference ’at a short wavelength and a large phase difference 値 at a long wavelength. Compared with general retardation films, the shorter the wavelength, the larger the phase difference 値. Because the phase difference 値 has a characteristic that is opposite to the general phase difference 値 for wavelength dependence, it is called inverse wavelength dispersion phase difference film. In the present invention, the phase difference R (λ 2) in the wavelength λ 2 selected from the wavelength range of 4 0 to 490 nm is the phase in the wavelength 1 selected from the wavelength range of 7 50 to 760 nm. The difference R (λ 1) divided by the 値 R (λ 2) / R (λ!) Position obtained is in the range of 0.5 or more and 0.9 5 or less is called an inverse wavelength dispersion retardation film. As the inverse wavelength dispersion retardation film described above, for example, a film composed of a cellulose acetate resin described in Japanese Patent Application Laid-Open No. 2000 — -15- (11) 200405042 1 3 7 1 16 can be used. The polymer mixed film composed of polyphenylene ether and polystyrene described in Japanese Patent Application Laid-Open No. 200 1-42 1 2 1 includes, for example, a polymer having a mandible skeleton described in Japanese Patent Application Laid-Open No. 2002-48919. For a polymer film such as a carbonate resin, specifically, a trade name "WRF" (a retardation film manufactured by Teijin Corporation) can be used.

In the present invention, these low-wavelength-dispersed or reverse-wavelength-dispersed retardation films and reflective linear polarizing films are laminated to form a laminated polarizing film. The retardation film is preferably a 1/4 wavelength retardation film. A 1/4 wavelength retardation film can be obtained by using two or more retardation films.

As shown in FIG. 2, the axis direction is shown in a schematic diagram. Although the optical axis 104 of the 1/4 wavelength retardation film 24 and the polarized light transmission axis 101 of the reflective linear polarizing film 21 preferably intersect at about 45 °, if it is 40 ~ 50 ° doesn't matter. With this, for the incident light from the 1/4 wavelength retardation film 24 side, the reflective linear polarizing film 21 will reflect the single-polarized light component, and the reflected polarized component will pass through the 1/4 wavelength retardation film. , It has excellent circular polarization for the entire field of visible light, and can make the brightness improvement system work effectively. Ideally, although the entire field of visible light is preferably 1/4 wavelength, the low-wavelength-dispersed or inverse-wavelength-dispersed retardation film used in the present invention generally exhibits a wavelength dependence of the phase difference. Here, in the present invention, a retardation film having a phase difference 値 of a wavelength λ 3 selected from a wavelength range of 5C to 5 5 5 nm is 1 3 0 to 1 50 nm is a 1/4 wavelength retardation film. . The optical axis of the retardation film is the direction of the maximum refractive index in the plane of -16- (12) (12) 200405042 of the retardation film. The retardation film used in the present invention may have biaxiality (biaxiality). The so-called biaxiality is the direction of the maximum refractive index in the plane of the retardation film is the X-axis direction. When the refractive indices in the respective axial directions are set to nx, ny, and ηz, then nycnz. When the ζ coefficient used to express the alignment state is expressed by (ηχ- ηζ) / (ηλ-ny), the alignment state of the ζ coefficient # 1 is called biaxiality. When the low-wavelength-dispersion or reverse-wavelength-dispersion retardation film is a 1 / 4-wavelength retardation film, as shown in FIG. 3 as the pattern direction, the axis direction is relative to the axis direction of the laminated polarizing film shown in FIG. 2 , Although the direction of the polarization transmission axis 105 of the new laminated absorption-type polarizing film 20 is preferably the same direction as the polarization transmission axis 1 0 1 of the reflective linear polarizing film 21, that is, it is preferably approximately 0 °, but as long as it is below 10 °, there is no problem in use. As described above, although the angle formed by the polarized light transmission axis 101 of the reflective linear polarizing film 21 and the optical axis 104 of the 1/4 wavelength retardation film 24 is intersected at about 45 °, as described above, It does not matter if it is 40 ~ 50 °. An absorption-type polarizing film is one that allows linearly polarized light of a specific vibration direction to pass through, and absorbs linearly polarized light in a direction orthogonal to it. The polarization transmission axis of the absorptive polarizing film refers to the direction in which the linearly polarized light of a specific vibration direction has the maximum transmittance when incident from the vertical direction of the polarizing film. The direction orthogonal to it becomes the polarization absorption axis. As this absorption-type polarizing film, for example, a well-known iodine-based polarizing film -17- (13) 200405042 or a dye-based polarizing film can be used. The so-called iodine-based polarizing film is a film in which iodine is absorbed in an extended polyvinyl alcohol film, and the so-called dye-based polarizing film is a film in which a dichroic dye is absorbed in an extended polyvinyl alcohol film. In order to improve the durability of these polarized thin films, it is preferable to cover one side or both sides with a polymer film. As the material of the polymer to be protected, cellulose diacetate, cellulose triacetate, polyethylene terephthalate, orthobornene resin and the like can be used.

Although the thickness of the absorptive polarizing film is not particularly limited, when the laminated polarizing film of the present invention is used in a liquid crystal display device or the like, the absorptive linearly polarizing film is preferably thin. Specifically, it is preferably ≦ mm, and more preferably 0.2 mm or less.

In the present invention, 'the main purpose is to optimize the system used to increase the brightness provided between the reflective linear polarizing film and the light source device'. Therefore, it is sometimes better not to use a diffuser which is generally used. Therefore, it is preferable to insert the light diffusion layer nfl having an in-plane retardation of nm 30 nm or less into the laminated polarizing film. The place where the light diffusing layer is laminated is not particularly limited. An example at this time is shown in Figs. 4 and 5. FIG. 4 (a) shows a layer composed of an absorption-type polarizing film 20, a reflection-type polarizing film 21, and a low-wavelength dispersion retardation film 2 2 shown in FIG. 1 (a). A light diffusion layer 26 is arranged on the outside of 20. (B) of FIG. 4 illustrates a case where a light diffusion layer 26 is disposed between the absorption-type polarizing film 20 and the reflection-type linear polarizing film 21. (C) of FIG. 4 shows a light diffusing layer 26 disposed between the reflective linear polarizing film 21 and the low-wavelength dispersion retardation film 22. (D) of FIG. 4 is a case where a light-diffusion layer 26 is arranged on the outer side of the thin film 22 at the low wavelength dispersion phase difference -18- (14) 200405042. Fig. 5 shows an example when the reverse dispersion retardation film 23 is used, and the low-wavelength dispersion retardation film 2 2 in Fig. 4 (a)) is replaced with the reverse wavelength dispersion retardation film 23. Since the light diffusion layer 2 6 preferably has a high total light transmittance, the total light transmittance is preferably more than 80%, and more preferably 90%. It is also used as an indicator of the diffusion performance of the light diffusion layer 26. Although the turbidity () ratio can be arbitrarily set according to the desired diffusion performance, it is usually 30% or more and 95% or less. The turbidity here is a material of the light diffusion layer 26 represented by the scattered light transmittance / total light transmittance X 1 00 (%), although it is not particularly limited, for example, an organic or inorganic material that has been dispersed therein is used. Polymer films of fine particles, or pressure-sensitive adhesives, refractive index-modulated light diffusion films, and the like. In order to reduce the number of parts of the laminated polarizing film and to make the thickness thinner, the light-diffusion pressure-sensitive adhesive having organic or inorganic fine particles is particularly one of the light-diffusion layers. Here, the material constituting the organic or inorganic fine particles is polymethyl methacrylate, polystyrene, polysiloxane, dioxane, titanium oxide, or the like. As the parent pressure-sensitive adhesive, a well-known thing can be used. For example, an acrylic pressure-sensitive adhesive, a rubber pressure-sensitive adhesive, a polysiloxane pressure-sensitive adhesive, or a polyurethane pressure-sensitive adhesive. Among them, an acrylic pressure-sensitive adhesive is preferably used. In order to make the laminated polarizing film of the present invention more rational, the film or layer formed with the pressure-sensitive adhesive is tightly sealed to prevent the loss of light wavelength due to unnecessary reflection ~ (D The phase is therefore up. Haze, through (expanded. Can be light expanded to reduce the dispersion is good, each adhesive is easy to apply, can be borrowed. Sense. 19- (15) 200405042 well-known adhesive can be used Various things. Examples include pressure-sensitive adhesives, rubber-based pressure-sensitive adhesives, polysiloxane polyurethane pressure-sensitive adhesives, etc. Among them, pressure-sensitive adhesives are preferred. Although the thickness of pressure-sensitive adhesives is not It is usually 1 / ^ m or more, 100 // m or less, and preferably; | 5 0 # m or less. The laminated polarizing film of the present invention can be laminated with a parallax film. A carbonate of an appropriate retardation film Films composed of synthetic polymers such as resins, acrylate resins, and polyethylene resins, or natural polymers such as cellulose diacetate as a single axis film, or coated on a transparent polymer film With compound or liquid A thin film made of a composition (for example, a nWV film sold by Japan Petrochemical Co., Ltd. "NH film" or "LC film", "VAG film" by Sumitomo Chemical Industries, etc.). When the purpose is optical compensation, the liquid crystal single film of the polarizing film is laminated. In order to prevent the loss due to the intermediate, it is best to implement the laminated polarizing film of the present invention with a pressure-sensitive adhesive. In the case of a reflective relaminated absorption polarizing film, it becomes a polarized light source device using the film side as a light exit surface. The light exit surface of the device is a display device with a liquid crystal panel for display. These polarized light source devices As for acrylic pressure-sensitive adhesives, the use of acrylate is particularly limited, but examples of phases that pass E 20 // m or more or are optically compensated are polymer resins, orthobornyl esters, cellulose triethyl or Optically anisotropically stretched in two axes. Phase difference air is arranged on the element side of the liquid crystal cell sold by Fuji Film Corporation. The light accumulates the layer. The linearly polarizing film side absorbs linearly polarized light, in which the polarized light source is a transmissive liquid crystal transmissive liquid crystal display -20- (16) 200405042 The device is based on the example shown in the sectional schematic diagram of FIG. 6 The example shown in FIG. 6 is the same as that shown in FIG. 4 (a), according to the light diffusion layer 26, the absorption-type polarizing film 20, the reflection-type linear polarizing film 21, and the low wavelength. A light source device 61 is arranged on the low-wavelength dispersed retardation film 22 on the low-wavelength dispersed retardation film 22 of the laminated polarizing film 10 in which the dispersed retardation film 22 is sequentially laminated, thereby forming a polarized light source device 64.

The light source device 61 shown in FIG. 6 is a form of a side light source. The light source device 61 includes a light source 51, a light guide plate 52, and a reflective plate 53 arranged on the back of the light guide plate 52. The light from the light source 51 on the side of the light plate 5 2 is reflected by a mirror 5 4 that covers one side of the light guide plate 5 2 that does not face the light source 51, and is first taken into the light guide plate 52 and advanced therethrough. In addition, the light is uniformly emitted from the front side of the light guide plate 52 in accordance with the reflection in the reflection plate 53. The light source device basically includes a light source member and a reflecting plate. When the light source device is in the form of a side light source shown in FIG. 6, the light source member is constituted by the light source 5 1 and the light guide plate 52. This light source device 61 is disposed on the low-wavelength dispersion retardation film 22 side of the laminated polarizing film 10 to form a polarized light source device 64. Furthermore, the absorption-type polarizing film 20 on the laminated polarizing film 10 is disposed facing the back surface of the liquid crystal cell 30 through the light-diffusing layer 26, and the retardation film 4 2 and the front-side absorption-type polarizing film 41 are disposed. A transmissive liquid crystal display device 6 is arranged on the front side of the liquid crystal cell 30. Although FIG. 6 shows an example of using the laminated polarizing film 10 shown in FIG. 4 (a), the laminated polarizing film can of course be used. 10 is changed to those shown in Figs. 4 (b) to (d), or changed to those shown in Figs. 5 (a) to (d). No -21-(17) 200405042 What is the tube, the light source device 6 1 provided with a light source member and a reflecting plate is disposed on the retardation film 22 or 23 side of the laminated polarizing film 10. A conventional polarized light source device has widely used a diffusion sheet 55 or a lens sheet 56 shown in FIG. 9. Although one or both of the polarized light source devices 64 of the present invention can be arranged, these will cause a disorder of the polarization state between the reflective linear polarizing film and the light source device, so it is best if possible. Do not configure.

In the polarized light source device 64 to the transmissive liquid crystal display device 67 shown in FIG. 6, the light source used in the light source device 61 is not particularly limited, but it is the same as long as it is a known polarized light source device or a liquid crystal display device. Land can be used in the present invention. A suitable light source 51 may specifically be a cold cathode tube, a light-emitting diode, an inorganic or organic electroluminescence (EL) lamp, or the like.

The reflection plate 53 is not particularly limited, but may be used in a well-known polarized light source device or a liquid crystal display device. Specifically, it can be a white plastic sheet with a cavity formed inside, and a plastic sheet coated with a white pigment such as titanium oxide or zinc on the surface. A multilayer sheet formed by laminating at least two types of plastic films with different refractive indices. Plastic sheet, sheet made of metal like aluminum or silver, etc. For these pieces, either a mirror finisher or a rough finisher can be used. The material of the plastic sheet constituting the reflecting plate is also not particularly limited, and may be, for example, polyethylene, polypropylene, polyethylene, polyethylene terephthalate, polyethylene naphthalate, polycarbonate, or original borneol. Olefin, polyurethane, polyacrylate, polymethyl methacrylate. The light guide plate 52 shown in FIG. 6 is a person who can take in -22- (18) 200405042 light emitted from the light source 51 into the inside as a planar light emitter, or can use a well-known polarized light source device or Used in liquid crystal display devices. The light guide plate is made of, for example, a plastic sheet or a glass plate, and may be one that has been subjected to a concave-convex process, a white-dot printing process, or a full-image process on the back side. When the light guide plate is made of a plastic sheet, although the material is not particularly limited, it is preferable to use polycarbonate, orbornene-based resin, polymethyl methacrylate, or the like.

A diffusion sheet 5 5 (shown in FIG. 9) arranged as necessary on the exit surface side of the light source device is a sheet that allows incident light to be transmitted randomly. Usually, the combined light transmittance is above 60% and the turbidity is between More than 10% of optical components. Here, the higher the total light transmittance of the diffusion sheet is, the better, more preferably, it has a total light transmittance of 80% or more. Although the diffusion sheet is not particularly limited, for example, a plastic sheet or a glass plate obtained by roughening a plastic sheet or a glass plate or forming a cavity or adding particles to the inside can be used. Although the material of the so-called plastic sheet is not particularly limited, polyethylene, polypropylene, polyvinyl chloride, polyethylene terephthalate, polyethylene naphthalate, polycarbonate, and original borneol can be used. Ethylene resin, polyurethane, polyacrylate, polymethyl methacrylate. Although the roughening treatment is not particularly limited, it may be a sandblasting or emboss roll pressing process, or the surface may be coated with plastic particles, glass particles, or silicon dioxide particles. The method of mixing the particles in the resin. On the other hand, a lens sheet 5 6 (shown in FIG. 9), which is arranged on the exit surface side of the light source device as necessary, is a light collector that collects light emitted from the light source. The lens sheet may be, for example, a micro lens array formed with a fine number of prisms on a plastic sheet, or a micro lens array covered with a convex lens or a concave lens. -23- (19) 200405042

The transmissive liquid crystal display device of the present invention is a laminated polarizing film 10 as an exit surface of a polarized light source device 64 in the example shown in FIG. 6. A liquid crystal cell 30 and an absorption polarizing film 4 on the front side are arranged in this order. 1 adult. Here, one or more retardation films 42 are arranged between the liquid crystal unit 30 and the front-side absorption type polarizing diaphragm 41 as necessary. Furthermore, a light diffusion layer may be disposed on the front side of the liquid crystal cell 30 as necessary. Moreover, you may arrange both a retardation film and a light-diffusion layer. The optical diffusion layer preferably has an in-plane phase difference 値 below 30 mm. It is preferable that each member constituting the transmissive liquid crystal display device, particularly each member from the laminated polarizing film 10 to the front-side absorption polarizing film 41, is closely contacted by a pressure-sensitive adhesive. Build up. Furthermore, it is better that all adjacent members are closely laminated with each other by a pressure-sensitive adhesive.

The liquid crystal cell 30 used in the liquid crystal display device has a function of changing the alignment state of the liquid crystal by applying a voltage in order to switch the amount of transmitted light. The liquid crystal cell is enclosed between two substrates. On the inside of each of the two substrates, a back-side transparent electrode 31 and a front-side transparent electrode 3 2 are arranged, and the liquid crystal layer 3 3 is held between these. Although not shown, the liquid crystal cell 30 is additionally provided with an alignment film for aligning the liquid crystal layer 33, and for color display, it has a color filter layer and the like. In the present invention, the type of the liquid crystal constituting the liquid crystal cell 30 or the driving method thereof is not particularly limited, but a TN liquid crystal or a STN liquid crystal or the like, which is also known, can be used. In addition, the present invention can also be applied to various displays using polarized light, such as a thin film transistor (TFT) driving method, a vertical alignment (VA) method, an In-Plane driving method, and an optical compensation band (0 C B). -24- (20) 200405042

Regarding the front-side absorption-type polarizing film 41, the same thing as that described above as an example of the absorption-type polarizing film constituting the laminated polarizing film of the present invention can be used. The retardation film 42 disposed between the liquid crystal cell 30 and the front-side absorption-type polarizing film 41 according to necessity is usually a stretched film of a resin. A suitable example may be a polycarbonate resin or a polyacrylate. Synthetic thermoplastic polymers such as cyclic polyolefin resins, such as resins based on resins, poly-coded resins, polyvinyl alcohols, and borneol M-based resins, or natural polymers such as cellulose triacetate The film is stretched in one or two axes by an extension device such as a tensioner. Alternatively, a film obtained by applying a liquid crystal compound to a transparent polymer film, such as "WV film sold by Fujifilm", (trade name), "quoted by Nippon Petrochemical Co., Ltd." An LC film, (trade name), "νΑ (: film" (trade name), etc., sold by Sumitomo Chemical Industries, Ltd.) is used as the retardation film 42. Furthermore, when a light diffusion layer is laminated on the front side of the liquid crystal cell 30 In the case of the layer, the same thing as the previous description of the example of the light diffusing layer constituting the laminated polarizing film of the present invention can be used. The following is a detailed description of another embodiment of the present invention. When the present invention is using a reflective type When combining a retardation layer in a system for improving the brightness of a polarizing film, 'by using a retardation layer with a positive biaxial alignment, it is possible to maintain the brightness improvement effect achieved by the retardation layer in the room'. Use the sunlight outside the house. Generally, when you look at a liquid crystal display device, it is viewed from the approximate normal direction of the display screen. That is, Chamber from the primary light source means emitted to the rear side toward the normal direction, the back surface side by sequentially through the polarizing film -25- (21) 200 405 042

, Liquid crystal cell, front side polarizing film, etc. to form a display image and see. On the other hand, outside the house, although the sunlight must be taken into the light source device on the back side at a time, after the light is taken in, the light emitted mainly in the normal direction can be seen as if it were originally emitted from the light source device. Here, it is necessary to consider where the sunlight enters the liquid crystal display device and whether it reaches the light source device on the back side. That is, since the user stands in the normal direction of the display screen in order to see the display screen, sunlight cannot be incident from the normal direction. Or the user blocks the incidence of sunlight, and the liquid crystal display device enters into the shadow of the user, so the sunlight cannot be used. That is, when using sunlight, sunlight can only be incident from an angle where the user is not present, that is, it can be incident only from an angle other than the normal direction.

As mentioned earlier, the application of the polarization conversion function generated by the retardation layer to a brightness enhancement system can effectively use a display device indoors, that is, use a light emitted from a light source device to view a display screen, and Using a display device outside the house, that is, when the display screen is viewed in a state where external light such as sunlight is taken in, has the opposite effect. However, in the case where the light emitted from the light source device is used and the case where external light is used, the light path is different because the light path is different, that is, in the light path until external light reaches the light source device, if the retardation layer When not functioning, you can exclude the bad effects caused by @ 外 光. That is, although the retardation layer can function effectively in the normal direction, if the direction of incidence of sunlight is oblique and cannot function effectively, the bad influence caused by taking in sunlight can be ruled out. In general, the so-called positive biaxial retardation layer ′ has a large relation between its retardation function and the incident angle of light. Therefore, -26- (22) 200405042, by using a phase difference layer having the above-mentioned positive biaxiality, can effectively perform the phase difference function with respect to the normal direction, and has no phase difference function with respect to the oblique direction. , So you can have both indoor and outdoor functions.

Fig. 10 is a schematic cross-sectional view showing the layer structure of another laminated polarizing film 10 of the present invention. As shown in the figure, the laminated polarizing film 1 of the present invention is formed by sequentially laminating an absorptive polarizing film 20, a reflective linear polarizing film 21, and a retardation layer 1 2 3 having positive biaxial alignment. . At this time, the polarization transmission axis 105 of the absorption-type polarizing film 20 is approximately parallel to the polarization transmission axis 101 of the reflection-type linear polarizing film 21, as in the direction of the axis shown in (a) of FIG. 11.

Regarding the laminated body of the absorption-type polarizing film 20 and the reflection-type linearly-polarizing film 21 described above, a phase difference layer 1 2 3 having positive biaxial alignment is further laminated on the outside of the reflection-type linearly-polarizing film 21. The so-called positive biaxial alignment refers to the anisotropy of the surface refractive index, and refers to a case where the refractive index in the biaxial direction is larger than the refractive index in the thickness direction. Specifically, when the direction of the maximum refractive index in the plane of the layer is the X axis, the axis in the plane orthogonal to the plane is the y axis, the thickness direction is the z axis, and the When the refractive index is set to nx, ny, and nz, it means nx > ny > nz. In other words, the Nz coefficient = (nx — nz) / (nx-) used to indicate the alignment state is larger than 1. The retardation layer having positive biaxial alignment used in the present invention must have an Nz coefficient larger than 1.5, preferably 2 or more, still more preferably 3 or more, more preferably 5 or more. The optical axis of the retardation layer in this specification refers to the direction of the maximum refractive index ', that is, -27- (23) 200405042, the X-axis direction.

The material of the retardation layer 1 23 having positive biaxial alignment is not particularly limited. It may be a single layer or a multilayer body composed of two or more layers. In the case of lamination, the retardation films of the same kind may be laminated, or the retardation films of different kinds may be laminated. Examples of the retardation film include synthetic polymers such as cyclic polyolefin resins including polycarbonate resins, polypropylene resins, polyethylene resins, and original norbornene resins. Films made of natural polymers such as cellulose diacetate and cellulose triacetate extending in one or two axes, or layers made of a compound with optical anisotropy or a liquid crystal composition Aligned on transparent polymer film.

It has completely positive biaxial alignment, that is, it becomes a phase difference layer between nx and ny > nz. Although it can be produced by biaxially stretching synthetic polymers or natural polymers, it can also be used. Other uniaxially oriented films that are biaxially extended for synthetic polymers or natural polymers, that is, methods that use two nx> ny films and stick them together so that the respective extension axes are orthogonal 'It is made by a method of in-plane alignment of a biaxial compound such as an inorganic layered compound or a cholesteric liquid crystal, a method of applying a orthogonal layer to two layers composed of a uniaxial compound coated with a nematic liquid crystal, or the like. Although an i / 4 wavelength retardation layer having positive biaxial alignment can be produced by a biaxial stretching method of a synthetic polymer or a natural polymer, it can also be formed by combining two or more synthetic polymers or Natural polymer implements uniaxial alignment formed by uniaxial extension, that is, the nx> ny film makes the optical axis -28- (24) 200405042

The method of attaching them differently is to laminate two or more layers of a uniaxial compound such as a nematic liquid crystal and make the optical axis differently. The method is to use an inorganic layered compound or a cholesteric liquid crystal. The biaxial compound is a complete biaxially aligned retardation layer which is aligned in the plane, and is produced by a method such as a uniaxially oriented retardation layer. Here, when an optically anisotropic compound or a liquid crystal composition is subjected to alignment coating and a stretched film is laminated and used, the compound or the liquid crystal composition having optical anisotropy is stretched. The thickness of the film can be reduced by applying the coating alignment on the film.

When the retardation layer 123 is composed of a single layer or a multilayer body having two or more layers with the same optical axis, if the direction in which the retardation layer has the largest refractive index in the plane is the X axis, When the direction orthogonal to the X-axis in the plane is set to the y-axis, the thickness direction is set to the Z-axis, the refractive index in the respective axial directions is set to nx, ny, and nz, or the thickness of the layer is set to d, Then the in-plane phase difference 値 R is expressed by the above formula R = (nx — ny) xd. The X-axis direction with the largest refractive index in the plane is the backward phase axis, and the y-axis direction that is orthogonal to it in the plane is the leading phase axis. On the other hand, when the retardation layer is composed of two or more layers, and the optical axes of at least one pair constituting the retardation layer are not parallel, it is difficult to directly define the direction of the maximum refractive index in the retardation plane. . At this time, the two polarizing elements are arranged so that the polarization transmission axes of the two polarizers are parallel to each other, and the retardation layer is interposed therebetween and rotated to obtain the axial direction that produces the maximum transmittance. Therefore, it can be judged that the axis direction is equivalent to the backward phase axis, or equivalent to the leading phase axis. If it is equivalent to the backward phase axis, this axis is set to the X axis, or if it is equivalent to the leading phase axis, it is related to the -29- (25) 200405042

The axis orthogonal to the in-plane axis is set to the x-axis, and the in-plane phase difference 値 R in appearance is measured. In addition, when the two retardation films are laminated such that the respective backward phase axes are orthogonal to each other, the in-plane phase difference 整体 of the entire laminated body is theoretically the respective surfaces of the two retardation films. The difference of the internal phase difference 値, therefore, the backward phase axis of the retardation film having a large phase difference between the two planes becomes the backward phase axis (X-axis) of the entire laminated body. In this case, the X-axis (backward phase axis) direction is set as the optical axis of the retardation layer in either case.

As shown in FIG. U (a), as described above, with the absorption polarizing film 20 and the reflective linear polarizing film 21, the former polarized light transmission axis 1 005 and the latter polarized light transmission axis 1 〇1 are used as described above. Arranged in approximately parallel to maximize the brightness improvement effect. Therefore, when the retardation layer 1 2 3 having positive biaxial alignment is laminated, the phase of the polarized light transmission axis 1 〇1 of the reflective linear polarizing film 21 and the phase having positive biaxial alignment are adjusted by adjusting The angle formed by the optical axis 1 73 of the difference layer 1 2 3 can adjust the brightness and improve the efficiency. When the phase difference layer 1 2 3 having a positive biaxial alignment is a 1/4 wavelength phase difference layer, as shown in FIG. 1 1 As shown in (a) to (c), the polarization transmission axis 105 of the absorption-type polarizing film 20 and the polarization transmission axis of the reflective linear polarization film 21 are arranged substantially parallel. Moreover, these The polarized light transmission axes 105 and 101 and the optical axis 173 of the retardation layer 123 are arranged at an angle of 45 ° or 135 °, thereby maximizing the brightness enhancement effect. Practically, as long as these angles are set within i 5% of the center. In the present invention, since the main purpose is to optimize the brightness improvement system between the reflective polarized light -30- (26) (26) 200405042 film and the light source device, it is in the form shown in FIG. 9 On the other hand, in some cases, the diffusion sheet 55 used in a light source device is preferably not used. Therefore, it is preferable to incorporate the light diffusion layer into the laminated polarizing film. The position where the light diffusing layer is laminated is not particularly limited as long as the in-plane phase difference 値 of the light diffusing layer is 3 Onm or less. An example at this time is shown in FIG. 13. (A) of FIG. 13 has a layer structure composed of the absorptive polarizing film 20 / the reflective linear polarizing film 2 1 / the retardation layer 1 2 3 having positive biaxial alignment shown in FIG. 10. The light diffusion layer 26 is disposed outside the absorption-type polarizing film 20. Fig. 13 (b) shows the light diffusion layer 26 arranged between the absorption-type polarizing film 20 and the reflection-type linear polarizing film 21. (C) of FIG. 13 shows that the light diffusion layer 26 is disposed between the reflective linear polarizing film 21 and the retardation layer 1 2 3 having positive biaxial alignment. (D) of FIG. 13 shows that the light diffusion layer 26 is arranged outside the phase difference layer 1 2 3 having positive biaxial alignment. At this time, although the in-plane phase difference of the light diffusion layer 26 is of course the largest, Fortunately, it is below 30nm, but it can also be larger. The light diffusion layer 26 preferably has the same total light transmittance and haze ratio as described above. The material of the light diffusion layer 26 is the same as described above. Furthermore, in order to facilitate the handling of the laminated polarizing film obtained as described above, it is preferable to use a pressure-sensitive adhesive agent for adhesion between the formed films or layers. The type and thickness of the pressure-sensitive adhesive are as described above. Also, a retardation film for optical compensation can also be laminated in the same manner. Examples of the retardation film may be the same as those described above. -31-(27) 200405042 The laminated polarizing film may be a polarized light source device that uses the absorption-type polarizing film side as the light exit surface. Further, the liquid crystal cell for display can be disposed on the side of the absorption-type polarizing film in the polarized light source device to be a transmissive liquid crystal display device. These polarized light source devices and transmissive liquid crystal devices will be described with reference to the examples shown in the cross-sectional schematic diagrams in FIG. 14.

The example shown in FIG. 14 is the same as that shown in FIG. 13 (a), in which the light source device 61 is disposed on the retardation layer 123 and the reflective linear polarizing film in accordance with positive biaxial alignment. 21. The absorption-type polarizing film 20 and the light-diffusing layer 26 are laminated in this order to form a polarized light source device 64 on the retardation layer 1 23 side of the laminated polarizing film 10.

The light source device 61 in FIG. 14 is an edge light type, and includes a light source 5 1, a light guide plate 5 2, and a reflective plate 5 3 arranged on the back of the light guide plate 5 2, and from the side of the light guide plate 5 2. The light from the light source 5 1 is reflected by a reflecting plate 5 4 that covers one side of the light guide plate 5 2 that does not face the light source 51. With the reflection of the reflecting plate 5 3, the light is uniform from the front side of the light guide plate 5 2 To release. The light source device 61 basically includes a light source member and a reflecting plate. When the light source device 61 is a side-light type as shown in FIG. 14, the light source member 51 and the light guide plate 52 are used to constitute the light source member. This light source device 61 is disposed on the side of the laminated polarizing film 10 with a positive biaxially-aligned retardation layer 1 2 3 to form a polarized light source device 64. The side of the absorbing polarizing film 20 of the laminated polarizing film 10 is disposed facing the rear surface of the liquid crystal cell 30, and the retardation film 42 and the front side of the absorbing polarizing film 41 are disposed on the front side of the liquid crystal cell 30. A transmissive liquid crystal display device 65 is configured. Fig. 14 shows an example using the laminated polarizing film -32- (28) (28) 200405042 1 〇 shown in Fig. 13 (a), but of course, the laminated polarizing film 10 can also be changed to Fig. 13 ( b) ~ (d). No matter which laminated polarizing film is used, the light source device 61 having a light source member and a reflecting plate is disposed on the retardation layer 1 2 3 side of the laminated polarizing film 10. In the conventional polarized light source device, a diffusion sheet 55 or a lens sheet 56 shown in Fig. 9 has been widely used. Although one or both of the polarized light source devices 64 shown in FIG. 14 can be arranged, these may cause the disorder of the polarization state between the reflective polarizing film and the light source device. It is best not to configure if possible. As another example of the transmissive liquid crystal display device 67 of the present invention, as shown in the example of FIG. 14, the liquid crystal cell 30 and the front-side absorption type polarizing film 41 are sequentially arranged to emit light as a polarized light source device 64. 10 side of the laminated polarizing film. Here, if necessary, one or more retardation films are arranged between the liquid crystal cell 30 and the front-side absorption-type polarizing film 41. If necessary, a light diffusion layer may be disposed on the front side of the liquid crystal cell 30. Furthermore, both the retardation film and the light diffusion layer may be arranged at the same time. The light-diffusion layer preferably has an in-plane phase difference 値 of 30 nm or less. For each member constituting the transmissive liquid crystal display device, in particular, each member from the laminated polarizing film 10 to the front-side absorbing polarizing film 41, it is preferable that at least one pair of adjacent members is a pressure-sensitive adhesive. Carry out close-packing. Furthermore, it is more preferable that all adjacent members are adhered to each other with a pressure-sensitive adhesive. The liquid crystal cell 30 used in the liquid crystal display device 67 is as described above. Regarding the front-side absorption-type polarizing film 41, the same thing as that described in the case of the absorption-type polarizing film constituting the laminated polarizing film of the present invention described in -33- (29) 200405042 can be used as described above. Examples Although the examples of the present invention are shown below, the present invention is not limited to these examples. In addition, the materials used to make the laminated polarizing film in the examples are as follows.

(1) Absorptive polarizing film SRW062A: Iodine-based absorptive polarizing film, obtained by Jiayou Chemical Industry Co., Ltd. (2) Reflective polarizing film DBEF-P: Laminate two kinds of polymer films and use refractive index anomaly Anisotropic thin films with reflectivity due to the properties were obtained by Sumitomo 3M. (3) a retardation film (a retardation layer)

SEF340138, SEF460275, SEF460565, and SEF460690: All are thin films with ordinary wavelength dispersion properties extended from polycarbonate resins. They were obtained from Sumitomo Chemical Industries, Ltd. SEN340 1 40, SEN49 02 7 5: Low-wavelength dispersion retardation film extended from original norbornene resin " ARTON "sold by JSR Co., Ltd., obtained by Sumitomo Chemical Industry Co., Ltd. S EW48 0 1 8 3 : Inverse wavelength dispersion retardation film manufactured by Teijin Co., Ltd., obtained by Sumitomo Chemical Industry Co., Ltd. For these retardation films, an automatic multi-refractive index manufactured by Oji Measurement Co., Ltd. -34- (30) 200405042 is used Calculate "KOBRA — 21 ADH" to obtain the index R (4 8 3 nm) / R of the wavelength dispersion of the phase difference calculated from the phase difference 値 R (549nm) at 549nm, and the phase difference 483 at 483nm and 755nm. (7 5 5 nm) and Nz coefficient at 5 8 9 nm. Similarly, an automatic multi-refractive index meter "KOBRA-2 2 AD AD '" manufactured by Oji Measurement Co., Ltd. was used at a wavelength of 5 The in-plane phase difference 値 and the N ζ coefficient were measured at 50 nm. The results are shown in Tables 1-1, 1, and 2 °. Table 1 to 1 R (5 49nm) R (4S3nm) R (T55nm) Nz coefficient SEF3 40 1 3 8 1 40nm 1.10 1.34 SEN340140 1 4 3 nm 1.01 1.44 SE W4 8 0 1 3 8 1 4 1 nm 0.83 0.89 8 nm 1.33 SEN490275 2 7 5 nm 0.99

(4) Light-diffusing layer light-diffusing pressure-sensitive adhesive # Β: an in-plane phase difference 値 of 0 mm ′ and -35- (31) 200405042 an acrylic pressure-sensitive pressure-sensitive adhesive having fine particles dispersed and a turbidity of 78%, Obtained by Sumitomo Chemical Industries, Ltd. Reference example 1

The light source device was removed from the TFT color liquid crystal module "NL 1 02 7 6AC 24 — 0 5" manufactured by Japan Electric Co., Ltd. The light source device is in the form of one-side light. A cold-cathode tube is arranged at the end of the light guide plate, and a reflective plate composed of a white plastic sheet is arranged on the light guide plate. Two lens sheets are arranged on the light guide plate, and further above it. With one diffuser. In this light source device, it is also possible to remove only the diffusion sheet, and reconfigure the "Lightup" as a diffusion sheet made by KiMOTO Co., Ltd. to become a light source device 80 for evaluation. As shown in FIG. On the adhesive agent 8 2 side, a laminated film 8 3 and 1.1 mm thick which is closely laminated in accordance with the order of the reflective linear polarizing film 21, the light diffusion layer 26, the absorption polarizing film 20, and the pressure-sensitive adhesive agent 8 2 is applied. A polarized light source device 8 5 is produced by attaching the glass plates 81 together and placing the glass plate 81 on the light source device 80 as an upper side. A polarimeter is used for the polarized light source device 85. (Trade name "BM-7" manufactured by Tope On Co., Ltd.) was used to measure the transmission brightness. The results are shown in Table 2. Example 1 The order is pressure-sensitive adhesive # 7 / absorptive linear polarizing film SRW0 6 2A / Light Diffusion Sensitive Adhesive # B / Reflective Linear Polarizing Film DBEF — P / Pressure Sensitive Adhesive # 7 / Low Wavelength Dispersion Phase Difference Film -36- (32) 200405042

S ENE 3 4 0 1 4 0, and the polarization transmission axis of the absorption linear polarizing film is parallel to the polarization transmission axis of the reflective linear polarizing film, and the polarization transmission axis of the reflective linear polarizing film is tightly laminated and low-wavelength dispersed. The optical axis of the retardation film is crossed at 4 5 ^ to produce the laminated polarizing film 10 of the present invention. As shown in FIG. 8, the laminated film 8 3 used in Reference Example 1 was replaced with the laminated glass film 8 1 on the pressure-sensitive adhesive 8 2 side so that the laminated glass film 81 was placed on the upper side. The mm-thick glass plate 81 was placed on the light source device 80 used in Reference Example 1 to produce a polarized light source device 86 according to the present invention. For this polarized light source device 86, the transmission brightness was measured by the same method as in Reference Example 1. The results are shown in Table 2. For Reference Example 1, the brightness enhancement effect achieved by adding the low-wavelength dispersive retardation film 22 (SEN3 40 1 40) is more than 1.5 times, and a high-brightness polarized light source device is obtained. Example 2

Except that the low-wavelength dispersion retardation film SEN340 1 40 in Example 1 was used instead of the reverse-wavelength dispersion retardation film SEW4 8 0 1 3 8, the rest were evaluated in the same manner as in Example 1. The results are shown in Table 2. Compared with Reference Example 1, the brightness enhancement effect achieved by adding the reverse wavelength dispersion retardation film SEW48 0 1 3 8 is more than 1.05 times, and a high-brightness polarized light source device is obtained. Comparative Example 1 Except that instead of the low-wavelength dispersion retardation film -37- (33) 200405042 SEN3 40 1 40 in Example 1, a retardation film SEF3 40 1 3 8 with ordinary wavelength dispersion characteristics was used. Evaluation was performed in the same manner as in Example 1. The results are shown in Table 2. Compared with Reference Example 1, the brightness improvement effect achieved by adding the retardation film SEF 3 4 0 1 3 8 stagnates at less than 1.05 times. Table 2 The brightness of the transmittance relative to Reference Example 1 is 6 64 cd / m2 Example 1 699 cd / m2 1 · 〇8 times Example 2 703 cd / m2 1. 〇9 times Comparative Example 1 671 cd / m2 1.04 times

Reference example 2

Except that the diffuser sheet "Lightap 100TL4" used in the light source device 80 used in Reference Example 1 was changed to a diffuser sheet "Lightup 100SXE" manufactured by KiMOTO Co., Ltd., it was evaluated in the same manner as in Reference Example 1. It was evaluated. The results are shown in Table 3. Example 3 A laminated polarizing film produced in Example 1 and a 1.1-mm-thick glass plate were pasted together and placed in Reference Example 2 in the same state as in Example 1. The light source device used in the evaluation was evaluated in the same manner as in Reference Example. The results are shown in Table 3. Compared with Reference Example 2, a low -38- (34) 200405042 wavelength dispersion retardation film SEN40 1 40 was added. The achieved brightness improvement effect is more than 1.05 times, and a high-brightness polarized light source device is obtained. Example 4 The laminated polarizing film produced in Example 2 was pasted together with a 1.1-mm-thick glass plate. The author placed the light source device used in Reference Example 2 in the same state as in Example 2 and evaluated it in the same manner as in Reference Example 2. The results are shown in Table 3. Compared to Reference Example 2, it was added Inverse wavelength dispersion phase difference The luminance improving effect reached film SEW4 8 0 1 3 8 1.05 times or more, to obtain a polarized light source device with high luminance. Comparative Example 2

The laminated polarizing film produced in Comparative Example 1 and a 1.1-mm-thick glass plate were pasted together, and the light source device used in Reference Example 2 was placed in the same state as Comparative Example 1. 1 Perform the same evaluation. Compared with Reference Example 2, the brightness enhancement effect achieved by adding the retardation film SEF3 40 1 3 8 is stagnant at less than 1.5 times. • 39- (35) 200405042 Table 3 Brightness ratio of transmittance relative to Reference Example 2 Reference Example 2 583cd / m2 Example 3 6 1 7 cd / m 2 1 · 0 6 times Example 4 620cd / m2 1.0 6 times Comparative Example 2 597 cd / m2 1.02 times

Reference example 3

Remove the liquid crystal panel from the TFT color liquid crystal module "NL 1 0 2 7 6 AC 2 4-0 5" made by Japan Electric Co., Ltd., and change the diffuser film built into the light emitting side of the light source device into a company K i Μ Ο Τ Ο diffused film "Lightup 100TL4" becomes the light source device 80. As shown in Fig. 15, according to the reflective linear polarizing film 2 1 (DBEF-P), the light diffusion layer 2 6 (light diffusion pressure Adhesive #B), absorption-type polarizing film 20 (SRW062A), and pressure-sensitive adhesive 82 (pressure-sensitive adhesive # 7) are laminated in this order to produce a laminated film 1 8 3. At this time, the absorption-type polarizing film 2 The polarized light transmission axis of 0 is parallel to the reflective linear polarizing film 21. The polarized light transmission axis of 1 is arranged in parallel. The laminated film 183 and the 1.1 mm-thick glass substrate 81 are pasted together on the pressure-sensitive adhesive 82 side. A polarized light source device was produced by placing the glass plate 81 on the light source device 180 so that it faces upward. With respect to the polarized light source device 1 8 5, the transmission brightness and reflection brightness were measured by the method shown in (A) below. 'The results are shown in Table 4. -40- (36) 200405042 (A) Degree of Evaluation Method The polarized light source device 1 8 5 manufactured as described above is horizontally placed on a dome (trade name "ENV-B — 2" manufactured by Otsuka Optical Co., Ltd. As shown in FIG. 16, the ring-shaped fluorescent lamp 187 of the dome is horizontally arranged on the pedestal of the lower cover, and the ring-shaped fluorescent lamp 187 can be adjusted by adjusting the height from the pedestal (not shown). The lighting angle of the fluorescent lamp with respect to the base when lighting is 1 8 8 (the slope of the lamp with respect to the normal direction of the base) is adjusted to 15 °. A brightness meter 1 89 (manufactured by TOP CON Co., Ltd.) is arranged above the base. Trade name " BM — 7 ") to measure the brightness. The measurements are all performed in a dark room. (A- 1) The light source device 1 80 is lit by the brightness, and the ring fluorescent lamp 1 8 7 is turned off In the state, the transmission brightness of the polarized light source device 1 8 5 is measured by a luminance meter 1 8 9. (A-2) Measurement of reflection brightness

The light source device 180 was turned off, and the reflection brightness of the polarized light source device 1 8 5 was measured by a luminance meter 1 89 while the ring-shaped fluorescent lamp was turned on. Throughout Example 5 A phase difference film SEF4 602 7 5 (in-plane phase difference 値 2 75 nm) and a phase difference film SEF3 40 1 3 8 were made as if the optical axes of the two were orthogonal to each other by the pressure-sensitive adhesive # 7. (In-plane retardation 値 138 nm) is tightly laminated to produce a quarter-wavelength retardation layer having positive biaxial alignment. For -41-(37) 200405042, this 1/4 wavelength retardation layer with positive biaxial alignment is measured by the automatic multi-refractive index meter `` KOBRA — 2 1 ADH " manufactured by Oji Measurement Co., Ltd. In-plane phase difference 値 and Nz coefficient at 55 nm. The results are shown in Table 4.

The quarter-wave retardation layer 123 having positive biaxial alignment produced here is a first retardation film 123a (SEF460275) and a second retardation film 1 2 3 b (see FIG. 17). SEF 3 4 0 1 3 8) laminated with pressure-sensitive adhesive 82 (pressure-sensitive adhesive # 7). In addition, as shown in the same figure, on the first retardation film 123 a (SEF46 0275) side of the 1/4 wavelength retardation layer 1 2 3, the laminated film 183 produced in Reference Example 3 is subjected to pressure sensing. The adhesive agent 82 is closely laminated on the reflective linear polarizing film 21 side to produce a laminated polarizing film 10. At this time, the polarization transmission axis of the reflective linear polarizing film 21 and the optical axis of the quarter-wave retardation layer 123 having positive biaxial alignment are arranged or crossed at 45 °. This laminated polarizing film 10 is laminated to a 1.1 mm thick glass plate 81 on the pressure-sensitive adhesive 8 2 side of the laminated film 83, and is disposed as if the glass plate 81 is an upper side. A polarized light source device 1 8 6 was fabricated on the light source device 1 80 used in Reference Example 3. Regarding this polarized light source device 1 8 6, the transmission brightness and the reflection brightness were measured by the same method as in Reference Example 3. The results are shown in Table 4. Example 6 The phase difference film SEF460690 (in-plane phase difference 値 700 nm) and the phase difference were thin by the pressure-sensitive adhesive # 7 such that the optical axes of the two orthogonally intersect with each other -42- (38) 200405042 film SEF460 5 65 ( The in-plane retardation (値 60 nm) is tightly laminated to produce a 1/4 wavelength retardation layer having positive biaxial alignment. The in-plane phase difference 値 and the Nz coefficient at a wavelength of 5 5 Onm are measured for the 1/4 wavelength retardation layer having positive biaxial alignment. Further, SEF460690 was used as the first retardation film 23a, and SEF460565 was used as the second retardation film 2 3 6. In the same state as in Example 5 (Fig. 17), a laminated polarizing film 10 was produced. The transmission brightness and reflection brightness were measured by the same method, and the results are shown in Table 4. Example 7

The phase difference film SEF490275 (in-plane phase difference 値 2 7 5nm) and the phase difference film SEF3 40 1 40 (in-plane phase difference 値 138nm) are made by the pressure-sensitive adhesive # 7 such that the optical axes of the two are orthogonal to each other. A tightly laminated layer is implemented to produce a 1/4 wavelength retardation layer having positive biaxial alignment. The in-plane phase difference 値 and the Nz coefficient at a wavelength of 5 5 Onm were measured for the 1/4 wavelength retardation layer having positive biaxial alignment. Further, using SEF4902 7 5 as the first retardation film 123a and SEF340 1 40 as the second retardation film 1 2 3 6, a laminated polarizing film was produced in the same state as in Example 5 (FIG. 17). 1 〇. The transmission brightness and reflection brightness were measured by the same method, and the results are shown in Table 4. Comparative Example 3 The reflective polarizing film 21 side of the laminated film 1 8 3 shown in FIG. 15 produced in Reference Example 3 is a retardation film SEF3 40 1 3 8 (in-plane-43- (39) 200405042 phase The differential polarization is 1 3 8 nm), and the laminated polarized film is produced by tightly laminating the pressure-sensitive adhesive # 7 such that the polarization axis of the former and the optical axis of the latter cross at 45 °. This laminated polarizing film was used in place of the 1/4 wavelength retardation layer having positive biaxial alignment in Example 5, and the others measured transmission brightness and reflection brightness in the same state as in Example 5. And the result table is not in Table 4. Table 4 First and second in-plane Nz transmission brightness * reflection brightness * retardation film retardation film phase difference 値 coefficient (cd / m2) (cd / m2) Reference Example 3 — — — 645 377 Example 5 SEF460275 SEF340138 132nm 2.49 696 340 [1.08] [0.90] Example 6 SEF460690 SEF460565 137nm 5.37 699 336 [1.08] [0.89] Example 7 SEN490275 SEN340140 138nm 2.21 692 336 [1.04] [0.89] Comparative Example 3 SEF340138 _ 138nm 1.44 671 318

[1.04] [0.84] * The bracketed value below is the brightness ratio compared to Reference Example 3. As can be seen from Table 4, compared with the polarized light source device of Reference Example 3, the normal 1/4 wavelength retardation film SEF is added. In Comparative Example 3 after 3 40 1 3 8 except that the transmission brightness improvement effect stagnates less than 1.05 times, the reflection is bright -44- (40) 200405042

The degree is also reduced to less than 0.85 times. In comparison, in Examples 5 to 7 in which a 1/4 wavelength retardation layer having positive biaxial alignment is added to the same polarized light source device, the transmission brightness is improved to that of Reference Example 3. 1.5 times or more. On the other hand, the ratio of the reflection brightness lower than that of Reference Example 1 is 0.85 times or more, and the reduction ratio of reflection brightness is stopped at 1.5. %the following. Therefore, by adding a retardation layer having positive biaxial alignment in addition to the absorption-type polarizing film and the reflection-type polarizing film, the brightness of the liquid crystal display device can be further improved, and even external light can be effectively used. Reference Example 4 Except that the light diffusion device Lightup 100TL4 in the light source device 8 used in Reference Example 3 was changed to a diffusion film `` Lightup 1 0 0 SXE '' made by κίΜΟΤ Co., the same as the reference example 3 Evaluation was performed in the same manner, and the results are shown in Table 5.

Example 8 A light source device used in Reference Example 4 was placed in the same state as in Example 5 by laminating the laminated polarizing film prepared in Example 5 on a 1.1 mm-thick glass plate. Evaluation was performed in the same manner as in Reference Example 4, and the results are not shown in Table 5. Example 9 A laminated polarizing film prepared in Example 6 was attached to a -45- (41) (41) 200405042 1 · 1 mm thick glass plate, and was placed in the same state as in Example 6 for reference. The light source device used in Example 4 was evaluated in the same manner as in Reference Example 4, and the results are shown in Table 5. Example 10 A light source device used in Reference Example 4 was placed in the same state as in Example 7 by applying the laminated polarizing film produced in Example 7 to a 1.1 mm thick glass plate. The evaluation was performed in the same manner as in Reference Example 4, and the results are shown in Table 5. Comparative Example 4 A laminated polarizing film having the same retardation film SEF 3 4 0 1 3 8 as the user used in Comparative Example 3 was laminated in the same state as that of Comparative Example 3 and the light source used in Reference Example 4 was arranged. The device was evaluated in the same manner as in Reference Example 4, and the results are shown in Table 5.

-46-(42) 200405042 Table 5 Nz transmission brightness * reflection brightness * in the first and second planes Phase difference film Phase difference film Phase difference 値 Coefficient (cd / m2) (cd / m2) Reference Example 4 — — One 583 288 Example 8 SEF460275 SEF340138 132nm 2.49 614 263 [1.05] [0.91] Example 9 SEF460690 SEF460565 137nm 5.37 617 261 [1.06] [0.91] Example 10 SEN490275 SEN340140 138nm 2.21 612 263 [1-05] [0.91] Comparative Example 4 SEF340138 — 138nm 1.44 597 248

[1.02] [0.86] * In the lower brackets, the brightness ratio compared to Reference Example 4

As can be seen from Table 5, compared to the polarized light source device of Reference Example 4, and Comparative Example 4 in which a normal 1 / 4-wavelength retardation film SEF 3 40 1 3 8 is added, the effect of improving the transmission brightness stagnates less than 1.05 times. , Its reflection brightness is also reduced to less than 0.9 times. Compared to this, for Examples 8 to 10 in which the same polarized light source device is added with a quarter-wave retardation layer having a positive biaxial alignment of 1/4, in addition to the transmission brightness compared to Reference Example 4, It is increased to more than 1.0 times. On the other hand, the ratio of the reflection brightness lower than that of Reference Example 3 to that of Reference Example 3 is 0.9 times or more, and the reduction ratio of reflection brightness is stopped at 1.0. %the following. -47- (43) 200405042 (Effect of the invention) By using the laminated polarizing film of the present invention on the right, the transmission brightness of a local transmission type liquid crystal display device can be improved. In addition, by using the laminated polarizing film of the present invention, in addition to improving the transmission brightness of the transmissive liquid crystal display device, since the utilization efficiency of external light can be improved, the visual effect of a display screen outdoors can be improved.

[Brief Description of the Drawings] Fig. 1 is a schematic cross-sectional view showing an example of the structure of a layer of a laminated polarizing film of the present invention. Fig. 2 is a schematic view showing an example of the axis configuration of the laminated polarizing film of the present invention. Fig. 3 is a schematic diagram showing the axis structure of the laminated polarizing film of the present invention in which an absorption-type polarizing film is laminated.

Fig. 4 is a schematic cross-sectional view showing an example of a layer structure of a laminated polarizing film of the present invention when a light diffusion layer has been laminated. Fig. 5 is a schematic sectional view showing another example of the layer structure of the laminated polarizing film of the present invention when a light diffusion layer has been laminated. Fig. 6 is a schematic sectional view showing an example of a liquid crystal display device of the present invention. Fig. 7 is a schematic sectional view showing the structure of a polarized light source device evaluated in Reference Example 1. Figs. Fig. 8 is a schematic sectional view showing the configuration of a polarized light source device evaluated in Reference Example 1. Figs. -48- (44) 200405042 Fig. 9 is a schematic sectional view showing the structure of a conventional transmissive liquid crystal display device. Fig. 10 is a schematic cross-sectional view showing an example of a constitution of a laminated polarizing film of the present invention. Fig. 11 is a schematic view showing an example of the axis configuration of the laminated polarizing film of the present invention.

Fig. 13 is a schematic cross-sectional view showing an example of a layer structure of a laminated polarizing film of the present invention when a light diffusion layer has been laminated. Fig. 14 is a sectional view showing an example of a liquid crystal display device of the present invention. Fig. 15 is a schematic sectional view showing the configuration of a polarized light source device evaluated in Reference Example 3. Figs. FIG. 16 is a schematic cross-sectional view showing the structure of a device for measuring brightness used in Reference Example 3. FIG.

Fig. 17 is a schematic sectional view showing the configuration of a polarized light source device evaluated in Example 6. Element comparison table 1 〇: Multilayer polarizing film 20: Absorptive polarizing film 2 1: Reflective linear polarizing film 22: Low-wavelength dispersion retardation film 2 3: Inverse-wavelength dispersion retardation film 2 4: Low-wavelength dispersion or reverse-wavelength dispersion 1/4 wavelength retardation film -49-(45) 200405042 2 6: light diffusion layer 3 0: liquid crystal cell 3 0, 3 1: transparent electrode 3 3: liquid crystal layer 40: back-side absorption type polarizing film 4 1: Front-side absorptive polarizing film 42: retardation film

5 1: Light source 5 2: Light guide plate 5 3: Reflective plate 5 4: Mirror 5 5: Diffusion sheet 5 6: Lens sheet 6 1: Light source device 64: Polarized light source device

6 7: Transmissive liquid crystal display device 8 0: Light source device used in reference example 8 1: Glass plate 8 2: Pressure-sensitive adhesive 8 3: Laminated film evaluated in Reference Example 1 8 5: In reference Polarized light source device 8 6 used in Example 1: Polarized light source device 8 used in Example 1: Ring phosphor 8 8: Illumination angle of ring phosphor when lighting -50- ( 46) 200405042 8 9: Brightness meter 90: Conventional transmission type liquid crystal display device 9 1: Conventional polarization light source device 1 〇1: Polarization transmission axis of reflective linear polarizing film 104: Optical axis of 1/4 wavelength retardation film 1 〇5: Polarized light transmission axis of the absorption-type polarizing film 1 2 3: Phase difference layer with positive biaxial alignment

123a, 123b: retardation film 172: polarization transmission axis of reflective polarizing film 1 7 3: light of 1/4 wavelength retardation layer with positive biaxial alignment 1 8 3: evaluated in Reference Example 3 Laminated film 1 8 5: Polarized light source device used in Reference Example 3 1 8 6: Polarized light source device used in Example 5

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Claims (1)

(1) 200405042 Patent application scope 1 · A laminated polarizing film, characterized in that: if the polarization axis of the absorption polarizing film and the reflective linear polarizing film are laminated approximately parallel to each other, moreover, At least one of a low-wavelength dispersive retardation film and a reverse-wavelength dispersive retardation film or a retardation layer having positive biaxial alignment is laminated on a reflective linear polarizing film side. 2 · If the laminated polarizing film of item 1 of the patent application, the retardation film has a phase difference of 1/4 wavelength, and the optical axis of the retardation film and the polarization transmission axis of the reflective linear polarizing film intersect at approximately 45 ° . 3. For the laminated polarizing film of the first item of the patent application, a retardation layer with positive biaxial alignment can be used as a 1/4 wavelength retardation layer. The polarization transmission axis of the reflective linear polarizing film and The optical axis of the 1/4 wavelength retardation layer of the biaxial alignment is laminated at approximately 45 ° or 1 3 5 °. 4. If the laminated polarizing film of the first scope of the patent application, the retardation layer having positive biaxial alignment is composed of a biaxially stretched film. 5. If the laminated polarizing film of the first scope of patent application ' The retardation layer having positive biaxial alignment is formed by laminating at least two retardation films having different optical axes. 6. The laminated polarizing film according to item 1 of the patent application scope. At least one retardation film is a uniaxially stretched film. 7. For example, the laminated polarizing film of the first scope of the patent application is' more and more '4' > Γ \ X 乃 -52- (2) 200405042 at least one layer of the laminated layer has an in-plane phase difference of 値 30nm or less Layer 8 · The light diffusion layer has adhesiveness, as in the laminated polarizing film of item 7 of the scope of patent application. 9 · If the laminated polarizing film according to item 1 of the patent application, at least one pair of adjacent films or layers is tightly laminated with a pressure-sensitive adhesive. 1 〇. A polarized light source device, characterized in that: The laminated polarizing film, the light source member, and the reflecting plate according to the first item are provided, and the light source member and the reflecting plate are arranged in order on the retardation film or retardation layer side of the laminated polarizing film. 1 1. A liquid crystal display device comprising the polarized light source device described in Item 10, a liquid crystal cell, and a front-side absorption polarizing film, and the liquid crystal cell and the front-side absorption polarizing film are arranged in order. On the side of the laminated polarizing film of the polarized light source device. 12. For a liquid crystal display device with a scope of application of patent No. π, a light diffusing layer having an in-plane phase difference of 30 nm or less is laminated between the liquid crystal cell and the front-side absorption type polarizing film. 13. In the case of a liquid crystal display device according to item 11 of the patent application scope, at least one pair of adjacent members of each member from the laminated polarizing film to the front-side absorptive polarizing film is tightly laminated with a pressure-sensitive adhesive. -53-