Optical component set

Abstract

To provide an optical laminate which enables weight reduction and visibility improvement of VR goggles.SOLUTION: An optical laminate according to an embodiment of the present invention comprises a laminated film including a base material and a surface treated layer, and a retardation member, where the base material of the laminated film and the retardation member are disposed next to each other, and the retardation member comprises a first retardation layer, adhesive layer, and second retardation layer arranged in the described order. The adhesive layer has a thickness of 0.5 to 1.3 μm, inclusive.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to an optical laminate, a lens unit, and a display method.

Background Art

[0002] Image display devices represented by liquid crystal display devices and electroluminescence (EL) display devices (for example, organic EL display devices) have been rapidly spreading. In image display devices, in order to realize image display and improve the performance of image display, generally, optical members such as polarizing members and retardation members are used (for example, see Patent Document 1).

[0003] In recent years, new applications of image display devices have been developed. For example, goggles with a display (VR goggles) for realizing Virtual Reality (VR) have begun to be commercialized. Since VR goggles are being considered for use in various scenarios, weight reduction, improvement of visibility, etc. are desired. Weight reduction can be achieved, for example, by thinning the lenses used in VR goggles. On the other hand, the development of optical members suitable for a display system using thin lenses is also desired.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] In view of the above, the main object of the present invention is to provide an optical laminate that can achieve weight reduction and improvement of visibility of VR goggles.

Means for Solving the Problems

[0006] 1. The optical laminate according to an embodiment of the present invention includes a laminated film having a base material and a surface treatment layer, and a retardation member. The base material of the laminated film and the retardation member are arranged adjacent to each other. The retardation member includes a first retardation layer, an adhesive layer, and a second retardation layer in this order, and the thickness of the adhesive layer is 0.5 μm or more and 1.3 μm or less. 2. The optical laminate according to 1 above may have a laminate smoothness of 0.7 arcmin or less. 3. In the optical laminate according to 1 or 2 above, the adhesive layer may be a cured layer of a resin. 4. In the optical laminate according to any one of 1 to 3 above, the surface smoothness of the laminated film may be 0.5 arcmin or less. 5. In the optical laminate according to any one of 1 to 4 above, the base material of the laminated film may contain a (meth)acrylic resin. 6. In the optical laminate according to any one of 1 to 5 above, the surface treatment layer of the laminated film may have an antireflection function. 7. In the optical laminate according to any one of 1 to 6 above, the first retardation layer may exhibit a refractive index characteristic of nx > ny ≧ nz, and may satisfy the relationship of Re(450) < Re(550) < Re(650). 8. In the optical laminate according to any one of 1 to 7 above, the second retardation layer may exhibit a refractive index characteristic of nz > nx ≧ ny. 9. The optical laminate according to any one of 1 to 8 above may have a Y value of the visual sensitivity correction single transmittance of 93% or more. 10. An embodiment of the present invention is a lens portion used in a display system that displays an image to a user, comprising: a reflective polarizing member that is emitted forward from the display surface of a display element representing an image and reflects light that has passed through a polarizing member and a first λ / 4 member; a first lens portion disposed on the optical path between the display element and the reflective polarizing member; a half mirror disposed between the display element and the first lens portion, which transmits light emitted from the display element and reflects the light reflected by the reflective polarizing member toward the reflective polarizing member; a second lens portion disposed in front of the reflective polarizing member; and an optical laminate according to any one of 1 to 9 above disposed on the optical path between the half mirror and the reflective polarizing member. 11. A display method according to an embodiment of the present invention includes the steps of: passing light representing an image emitted through a polarizing member and a first λ / 4 member through a half mirror and a first lens portion; passing the light that has passed through the half mirror and the first lens portion through an optical laminate described in any of 1 to 9 above; reflecting the light that has passed through the optical laminate toward the half mirror with a reflective polarizing member; making the light reflected by the reflective polarizing member and the half mirror permeable to the reflective polarizing member by the optical laminate; and passing the light that has passed through the reflective polarizing member through a second lens portion. [Effects of the Invention]

[0007] According to the optical laminate of the embodiment of the present invention, it is possible to reduce the weight of VR goggles and improve their visibility. [Brief explanation of the drawing]

[0008] [Figure 1] This is a schematic diagram showing the general configuration of a display system according to one embodiment of the present invention. [Figure 2] Figure 1 is a schematic cross-sectional view showing an example of the details of the lens section of the display system. [Figure 3] This is a schematic perspective view showing an example of a multilayer structure contained in a reflective polarizing film. [Modes for carrying out the invention]

[0009] Embodiments of the present invention will be described below with reference to the drawings, but the present invention is not limited to these embodiments. While the drawings may schematically represent the width, thickness, shape, etc., of each part compared to the embodiments in order to clarify the explanation, these are merely examples and do not limit the interpretation of the present invention. Furthermore, in the drawings, the same or equivalent elements are denoted by the same reference numerals, and redundant explanations may be omitted.

[0010] (Definitions of terms and symbols) The definitions of terms and symbols used in this specification are as follows: (1) Refractive index (nx, ny, nz) "nx" is the refractive index in the direction where the refractive index is maximum in the plane (i.e., the slow phase axis direction), "ny" is the refractive index in the direction perpendicular to the slow phase axis in the plane (i.e., the fast phase axis direction), and "nz" is the refractive index in the thickness direction. (2) In-plane phase difference (Re) "Re(λ)" is the in-plane phase difference measured with light of wavelength λnm at 23°C. For example, "Re(550)" is the in-plane phase difference measured with light of wavelength 550nm at 23°C. Re(λ) can be calculated using the formula: Re(λ) = (nx - ny) × d, where d (nm) is the thickness of the layer (film). (3) Phase difference in the thickness direction (Rth) "Rth(λ)" is the phase difference in the thickness direction measured with light of wavelength λnm at 23°C. For example, "Rth(550)" is the phase difference in the thickness direction measured with light of wavelength 550nm at 23°C. Rth(λ) can be calculated using the formula: Rth(λ) = (nx - nz) × d, where d (nm) is the thickness of the layer (film). (4) Nz coefficient The Nz coefficient is calculated using the formula Nz = Rth / Re. (5)Angle When referring to an angle in this specification, the angle includes both clockwise and counterclockwise directions with respect to the reference direction. Therefore, for example, "45°" means ±45°.

[0011] FIG. 1 is a schematic diagram showing the general configuration of a display system according to an embodiment of the present invention. In FIG. 1, the arrangement and shape of each component of the display system 2 are schematically illustrated. The display system 2 includes a display element 12, a reflective polarizing member 14, a first lens unit 16, a half mirror 18, a first retardation member 20, a second retardation member 22, and a second lens unit 24. The reflective polarizing member 14 is disposed in front of the display surface 12a side of the display element 12 and can reflect the light emitted from the display element 12. The first lens unit 16 is disposed on the optical path between the display element 12 and the reflective polarizing member 14, and the half mirror 18 is disposed between the display element 12 and the first lens unit 16. The first retardation member 20 is disposed on the optical path between the display element 12 and the half mirror 18, and the second retardation member 22 is disposed on the optical path between the half mirror 18 and the reflective polarizing member 14.

[0012] The half mirror, or components disposed forward from the first lens unit (in the illustrated example, the half mirror 18, the first lens unit 16, the second retardation member 22, the reflective polarizing member 14, and the second lens unit 24) may be collectively referred to as a lens unit (lens unit 4).

[0013] The display element 12 is, for example, a liquid crystal display or an organic EL display, and has a display surface 12a for displaying an image. The light emitted from the display surface 12a passes through a polarizing member (typically, a polarizing film) that may be included in the display element 12 and is emitted as the first linearly polarized light.

[0014] The first retardation member 20 includes a first λ / 4 member that can convert the first linearly polarized light incident on the first retardation member 20 into the first circularly polarized light. When the retardation member does not include a member other than the first λ / 4 member, the first retardation member may correspond to the first λ / 4 member. The first retardation member 20 may be provided integrally with the display element 12.

[0015] The half mirror 18 transmits the light emitted from the display element 12 and reflects the light reflected by the reflective polarizing member 14 toward the reflective polarizing member 14. The half mirror 18 is provided integrally with the first lens unit 16.

[0016] The second retardation member 22 includes a second λ / 4 member that can transmit the light reflected by the reflective polarizing member 14 and the half mirror 18 through the reflective polarizing member 14. When the second retardation member does not include a member other than the second λ / 4 member, the second retardation member may correspond to the second λ / 4 member. The second retardation member 22 may be provided integrally with the first lens unit 16.

[0017] The first circularly polarized light emitted from the first λ / 4 member included in the first retardation member 20 passes through the half mirror 18 and the first lens unit 16 and is converted into second linearly polarized light by the second λ / 4 member included in the second retardation member 22. The second linearly polarized light emitted from the second λ / 4 member is reflected toward the half mirror 18 without passing through the reflective polarizing member 14. At this time, the polarization direction of the second linearly polarized light incident on the reflective polarizing member 14 is the same as the reflection axis of the reflective polarizing member 14. Therefore, the second linearly polarized light incident on the reflective polarizing member 14 is reflected by the reflective polarizing member 14.

[0018] The second linearly polarized light reflected by the reflective polarizing member 14 is converted into second circularly polarized light by the second λ / 4 member included in the second retardation member 22, and the second circularly polarized light emitted from the second λ / 4 member passes through the first lens unit 16 and is reflected by the half mirror 18. The second circularly polarized light reflected by the half mirror 18 passes through the first lens unit 16 and is converted into third linearly polarized light by the second λ / 4 member included in the second retardation member 22. The third linearly polarized light passes through the reflective polarizing member 14. At this time, the polarization direction of the third linearly polarized light incident on the reflective polarizing member 14 is the same as the transmission axis of the reflective polarizing member 14. Therefore, the third linearly polarized light incident on the reflective polarizing member 14 passes through the reflective polarizing member 14.

[0019] The light transmitted through the reflective polarizing member 14 passes through the second lens unit 24 and enters the user's eye 26.

[0020] For example, the absorption axis of the polarizing member included in the display element 12 and the reflection axis of the reflective polarizing member 14 may be arranged substantially parallel to each other or substantially perpendicular to each other. The angle formed by the absorption axis of the polarizing member included in the display element 12 and the slow axis of the first λ / 4 member included in the first retardation member 20 is, for example, 40° to 50°, may be 42° to 48°, or may be about 45°. The angle formed by the absorption axis of the polarizing member included in the display element 12 and the slow axis of the second λ / 4 member included in the second retardation member 22 is, for example, 40° to 50°, may be 42° to 48°, or may be about 45°.

[0021] The in-plane retardation Re(550) of the first λ / 4 member is, for example, 100 nm to 190 nm, may be 110 nm to 180 nm, may be 130 nm to 160 nm, or may be 135 nm to 155 nm. The first λ / 4 member preferably exhibits an inverse dispersion wavelength characteristic in which the retardation value increases with the wavelength of the measurement light. The first λ / 4 member preferably satisfies the relationship of Re(450) < Re(550) < Re(650). Re(450) / Re(550) of the first λ / 4 member is, for example, 0.75 or more and less than 1, and may be 0.8 or more and 0.95 or less.

[0022] The in-plane retardation Re(550) of the second λ / 4 member is, for example, 100 nm to 190 nm, may be 110 nm to 180 nm, may be 130 nm to 160 nm, or may be 135 nm to 155 nm. The second λ / 4 member preferably exhibits an inverse dispersion wavelength characteristic in which the retardation value increases with the wavelength of the measurement light. The second λ / 4 member preferably satisfies the relationship of Re(450) < Re(550) < Re(650). Re(450) / Re(550) of the second λ / 4 member is, for example, 0.75 or more and less than 1, and may be 0.8 or more and 0.95 or less.

[0023] In the lens portion 4, a space may be formed between the first lens portion 16 and the second lens portion 24. In this case, it is preferable that the member disposed between the first lens portion 16 and the second lens portion 24 is integrally provided with either the first lens portion 16 or the second lens portion 24. For example, it is preferable that the member disposed between the first lens portion 16 and the second lens portion 24 is integrated with either the first lens portion 16 or the second lens portion 24 via an adhesive layer. With such a configuration, for example, the handling of each member can be improved. The adhesive layer may be formed of an adhesive or a tack. Specifically, the adhesive layer may be an adhesive layer or a tack layer. The thickness of the adhesive layer is, for example, 0.05 μm to 30 μm.

[0024] Figure 2 is a schematic cross-sectional view showing an example of the details of the lens section of the display system shown in Figure 1. Specifically, Figure 2 shows a first lens section, a second lens section, and a component positioned between them. The lens section 4 comprises a first lens section 16, a first laminated section 100 provided adjacent to the first lens section 16, a second lens section 24, and a second laminated section 200 provided adjacent to the second lens section 24. In the example shown in Figure 2, the first laminated section 100 and the second laminated section 200 are spaced apart. Although not shown, a half-mirror may be integrally provided with the first lens section 16. Hereinafter, the first laminated section may be referred to as an optical laminate.

[0025] The first laminated portion 100 includes a second phase difference member 22 and an adhesive layer (e.g., an adhesive layer) 41 disposed between the first lens portion 16 and the second phase difference member 22, and is integrally provided with the first lens portion 16 by the adhesive layer 41. The first laminated portion 100 further includes a first protective member 31 disposed in front of the second phase difference member 22. The first protective member 31 is laminated on the second phase difference member 22 via the adhesive layer (e.g., an adhesive layer) 42 and is disposed adjacent to the second phase difference member 22. The first protective member 31 may be located on the outermost surface of the first laminated portion 100. In this specification, "adjacent" includes not only directly adjacent but also adjacent via an adhesive layer.

[0026] In the example shown in FIG. 2, the second retardation member 22 includes, in addition to the second λ / 4 member (first retardation layer) 22a, a member (second retardation layer) 22b having a refractive index characteristic of nz > nx ≧ ny. The second retardation member 22 has a laminated structure of the first retardation layer 22a and the second retardation layer 22b. By using the member 22b having the relationship of nz > nx ≧ ny, light leakage (for example, light leakage in an oblique direction) can be prevented. As shown in FIG. 2, in the second retardation member 22, it is preferable that the second λ / 4 member 22a is located in front of the member 22b having the relationship of nz > nx ≧ ny.

[0027] The second λ / 4 member (first retardation layer) 22a and the member (second retardation layer) 22b having the relationship of nz > nx ≧ ny are laminated via an adhesive layer 50. The second retardation member 22 includes the first retardation layer 22a, the adhesive layer 50, and the second retardation layer 22b. By laminating the retardation layers using the adhesive layer 50, the occurrence of cracks and fractures in the retardation layers can be suppressed. Also, peeling between the retardation layers can be prevented. And an optical laminate excellent in durability can be obtained. For example, when the thickness of at least one of the first retardation layer and the second retardation layer (for example, the second retardation layer) is 10 μm or less, cracks and fractures tend to occur.

[0028] The above second λ / 4 member preferably has a refractive index characteristic of nx > ny ≧ nz. Here, "ny = nz" includes not only the case where ny and nz are exactly equal but also the case where they are substantially equal. Therefore, within a range not impairing the effects of the present invention, ny < nz may occur. The Nz coefficient of the second λ / 4 member is preferably 0.9 to 3, more preferably 0.9 to 2.5, still more preferably 0.9 to 1.5, and particularly preferably 0.9 to 1.3.

[0029] The second λ / 4 member is formed of any suitable material that can satisfy the above characteristics. The second λ / 4 member can be, for example, a stretched film of a resin film or an alignment cured layer of a liquid crystal compound.

[0030] Examples of resins included in the above-mentioned resin film include polycarbonate resins, polyester carbonate resins, polyester resins, polyvinyl acetal resins, polyarylate resins, cyclic olefin resins, cellulose resins, polyvinyl alcohol resins, polyamide resins, polyimide resins, polyether resins, polystyrene resins, and acrylic resins. These resins may be used individually or in combination. Methods of combination include blending and copolymerization. When the second λ / 4 member exhibits inverse dispersion wavelength characteristics, a resin film containing a polycarbonate resin or a polyester carbonate resin (hereinafter sometimes simply referred to as a polycarbonate resin) can be suitably used.

[0031] Any suitable polycarbonate resin can be used as the above-mentioned polycarbonate resin. For example, the polycarbonate resin includes structural units derived from fluorene-based dihydroxy compounds, structural units derived from isosorbide-based dihydroxy compounds, and structural units derived from at least one dihydroxy compound selected from the group consisting of alicyclic diols, alicyclic dimethanol, di, tri, or polyethylene glycol, and alkylene glycol or spiroglycol. Preferably, the polycarbonate resin includes structural units derived from fluorene-based dihydroxy compounds, structural units derived from isosorbide-based dihydroxy compounds, structural units derived from alicyclic dimethanol, and / or structural units derived from di, tri, or polyethylene glycol; more preferably, it includes structural units derived from fluorene-based dihydroxy compounds, structural units derived from isosorbide-based dihydroxy compounds, and structural units derived from di, tri, or polyethylene glycol. The polycarbonate resin may optionally include structural units derived from other dihydroxy compounds. Further details regarding polycarbonate resins suitably used for the second λ / 4 member and methods for forming the second λ / 4 member are described, for example, in Japanese Patent Publication Nos. 2014-10291, 2014-26266, 2015-212816, 2015-212817, and 2015-212818, and the descriptions in these publications are incorporated herein by reference.

[0032] The thickness of the second λ / 4 member, which is composed of a stretched resin film, is, for example, 10 μm to 100 μm, preferably 10 μm to 70 μm, and more preferably 20 μm to 60 μm.

[0033] The orientation-solidified layer of the above-mentioned liquid crystal compound is a layer in which the liquid crystal compound is oriented in a predetermined direction within the layer, and this orientation state is fixed. Note that the term "orientation-solidified layer" is a concept that includes the orientation-cured layer obtained by curing liquid crystal monomers, as described later. In the second λ / 4 member, typically, rod-shaped liquid crystal compounds are oriented in a state where they are aligned along the slow axis direction of the second λ / 4 member (homogenous orientation). Examples of rod-shaped liquid crystal compounds include liquid crystal polymers and liquid crystal monomers. Preferably, the liquid crystal compound is polymerizable. If the liquid crystal compound is polymerizable, the orientation state of the liquid crystal compound can be fixed by polymerizing it after orientation.

[0034] The above-mentioned oriented solidified layer of liquid crystal compound (liquid crystal oriented solidified layer) can be formed by applying an orientation treatment to the surface of a predetermined substrate, coating the surface with a coating liquid containing the liquid crystal compound to orient the liquid crystal compound in the direction corresponding to the orientation treatment, and fixing the orientation state. Any appropriate orientation treatment can be used as the orientation treatment. Specifically, these include mechanical orientation treatment, physical orientation treatment, and chemical orientation treatment. Specific examples of mechanical orientation treatment include rubbing treatment and stretching treatment. Specific examples of physical orientation treatment include magnetic field orientation treatment and electric field orientation treatment. Specific examples of chemical orientation treatment include oblique deposition and photo-orientation treatment. Any appropriate conditions can be adopted for each orientation treatment depending on the purpose.

[0035] The orientation of liquid crystal compounds is achieved by treating them at a temperature that exhibits the liquid crystal phase, depending on the type of liquid crystal compound. This temperature treatment causes the liquid crystal compound to enter a liquid crystal state, and it then orients according to the orientation treatment direction on the substrate surface.

[0036] In one embodiment, the orientation state is fixed by cooling the liquid crystal compound oriented as described above. If the liquid crystal compound is polymerizable or crosslinkable, the orientation state is fixed by subjecting the liquid crystal compound oriented as described above to a polymerization treatment or a crosslinking treatment.

[0037] As the above-mentioned liquid crystal compound, any suitable liquid crystal polymer and / or liquid crystal monomer can be used. The liquid crystal polymer and liquid crystal monomer may be used individually or in combination. Specific examples of liquid crystal compounds and methods for producing liquid crystal alignment solidified layers are described, for example, in Japanese Patent Publication No. 2006-163343, Japanese Patent Publication No. 2006-178389, and International Publication No. 2018 / 123551. The descriptions in these publications are incorporated herein by reference.

[0038] The thickness of the second λ / 4 member, which is composed of a liquid crystal alignment solidification layer, is, for example, 1 μm to 10 μm, preferably 1 μm to 8 μm, more preferably 1 μm to 6 μm, and even more preferably 1 μm to 4 μm.

[0039] The phase difference Rth(550) in the thickness direction of the member (second phase difference layer) whose refractive index characteristics exhibit the relationship nz>nx≧ny is preferably -260nm to -10nm, more preferably -230nm to -15nm, and even more preferably -215nm to -20nm. In one embodiment, the second phase difference layer is a so-called positive C plate whose refractive index exhibits the relationship nx=ny. Here, "nx=ny" includes not only the case where nx and ny are exactly equal, but also the case where nx and ny are substantially equal. For example, it includes the case where Re(550) is less than 10nm. In another embodiment, the second phase difference layer exhibits the relationship nx>ny. In this case, the in-plane phase difference Re(550) of the second phase difference layer is preferably 10nm to 150nm, more preferably 10nm to 80nm.

[0040] A component exhibiting the relationship nz > nx ≥ ny in refractive index characteristics can be formed from any suitable material. Preferably, it is composed of a film containing a liquid crystal material fixed in a homeotropic orientation. The liquid crystal material (liquid crystal compound) that can be homeotropically oriented may be a liquid crystal monomer or a liquid crystal polymer. Specific examples of such liquid crystal compounds and film formation methods are listed in paragraphs

[0020] to

[0042] of Japanese Patent Application Publication No. 2002-333642. In this case, the thickness is preferably 0.1 μm to 5 μm, and more preferably 0.5 μm to 4 μm.

[0041] As another preferred example, a component whose refractive index characteristics are such that nz > nx ≥ ny may be a phase difference film formed from a fumarate diester resin as described in Japanese Patent Application Publication No. 2012-32784. In this case, the thickness is preferably 5 μm to 50 μm, and more preferably 10 μm to 35 μm.

[0042] The adhesive layer 50 contained in the second phase difference member 22 can be formed with any suitable adhesive. The adhesive is one that irreversibly changes from liquid to solid during the process of forming the adhesive layer, is fluid when applied, and hardens through a curing treatment (e.g., irradiation with active energy rays, heating). Preferably, a curable adhesive is used. Specifically, the adhesive layer 50 is preferably a cured resin layer. Preferably, an ultraviolet curable adhesive is used as the curable adhesive.

[0043] The above UV-curable adhesive contains a curable monomer such as a compound having a (meth)acryloyl group or a compound having a vinyl group. Preferably, a compound having a (meth)acryloyl group is used. Here, (meth)acryloyl group refers to an acryloyl group and / or a methacryloyl group.

[0044] The thickness of the adhesive layer included in the phase difference member is 1.3 μm or less, preferably 1.1 μm or less, and more preferably 0.9 μm or less. With such a thickness, an optical laminate with extremely excellent smoothness can be obtained. Specifically, when forming the adhesive layer, the adhesive may shrink during curing. This curing shrinkage can greatly affect the smoothness of the resulting optical laminate. In the above display system, the image may be magnified in the lens section (for example, by a convex lens), and the smoothness of the optical laminate can greatly affect visibility. A thin adhesive layer reduces the effect of curing shrinkage, making it possible to obtain an optical laminate with excellent smoothness. Furthermore, such an optical laminate can achieve remarkably excellent visibility in the above display system. For example, a clear image without distortion can be achieved. On the other hand, the thickness of the adhesive layer included in the phase difference member is preferably 0.5 μm or more from the viewpoint of durability.

[0045] The above-mentioned first protective member typically includes a substrate. The thickness of the substrate is preferably 5 μm to 80 μm, more preferably 10 μm to 50 μm, and even more preferably 15 μm to 40 μm. The surface smoothness of the substrate is preferably 0.7 arcmin or less, more preferably 0.6 arcmin or less, and even more preferably 0.5 arcmin or less. The surface smoothness can be measured by focusing the irradiated light onto the surface of the object.

[0046] The substrate can be composed of any suitable film. Examples of materials that make up the main component of the film constituting the substrate include cellulosic resins such as triacetylcellulose (TAC), polyester resins, polyvinyl alcohol resins, polycarbonate resins, polyamide resins, polyimide resins, polyethersulfone resins, polysulfone resins, polystyrene resins, cycloolefin resins such as polynorbornene, polyolefin resins, (meth)acrylic resins, acetate resins, etc. Here, (meth)acrylic refers to acrylic and / or methacrylic. In one embodiment, the substrate is preferably composed of a (meth)acrylic resin. By using a (meth)acrylic resin, a substrate with excellent smoothness (for example, satisfying the above surface smoothness) can be manufactured by extrusion molding. Thus, a protective member with excellent smoothness can be obtained.

[0047] The first protective member is preferably composed of a laminated film having a base material and a surface treatment layer formed on the base material. The thickness of the laminated film is preferably 10 μm to 80 μm, more preferably 15 μm to 60 μm, and even more preferably 20 μm to 45 μm. The thickness of the surface treatment layer is preferably 0.5 μm to 10 μm, more preferably 1 μm to 7 μm, and even more preferably 2 μm to 5 μm.

[0048] The surface treatment layer typically includes a hard coat layer. The hard coat layer is typically formed by applying a hard coat layer-forming material to a substrate and curing the applied layer. The hard coat layer-forming material typically includes a curable compound as a layer-forming component. Examples of curing mechanisms for curable compounds include thermosetting and photocuring. Examples of curable compounds include monomers, oligomers, and prepolymers. Preferably, a polyfunctional monomer or oligomer is used as the curable compound. Examples of polyfunctional monomers or oligomers include monomers or oligomers having two or more (meth)acryloyl groups, urethane (meth)acrylate or urethane (meth)acrylate oligomers, epoxy monomers or oligomers, and silicone monomers or oligomers.

[0049] The thickness of the hard coat layer is preferably 0.5 μm to 10 μm, more preferably 1 μm to 7 μm, and even more preferably 2 μm to 5 μm.

[0050] The surface treatment layer preferably includes a functional layer. The functional layer preferably functions as an anti-reflective layer. In a preferred embodiment, the surface treatment layer includes the hard coat layer and the anti-reflective layer in that order from the substrate side. The thickness of the functional layer is preferably 0.05 μm to 10 μm, more preferably 0.1 μm to 5 μm, and even more preferably 0.1 μm to 2 μm.

[0051] The first protective member having a surface treatment layer may be positioned such that the surface treatment layer is located on the front side. Specifically, the surface treatment layer may be located on the outermost surface of the first laminated portion. The surface treatment layer may have any suitable function. Preferably, the surface treatment layer has an anti-reflective function, for example, from the viewpoint of suppressing light loss at the interface with air and improving visibility. In one embodiment, the first protective member preferably has a maximum value of 2.0% or less in the 5° specular reflectance spectrum in the wavelength range of 420 nm to 680 nm, more preferably 1.2% or less, even more preferably 1.0% or less, and particularly preferably 0.8% or less. Here, the 5° specular reflectance can be measured, for example, by preparing a measurement sample by attaching the object to be measured to a black acrylic plate using an adhesive, and using a spectrophotometer (manufactured by Hitachi High-Technologies Corporation, product name "U-4100") as the measuring device, with the angle of incidence of light on the measurement sample being 5°.

[0052] The surface smoothness of the first protective member is preferably 0.5 arcmin or less, more preferably 0.4 arcmin or less. Substantively, the surface smoothness of the first protective member is, for example, 0.1 arcmin or more. The laminate smoothness of the optical laminate 100 is preferably 0.7 arcmin or less, more preferably 0.6 arcmin or less, and even more preferably 0.5 arcmin or less. By satisfying such laminate smoothness of the optical laminate, the generation of diffuse light can be suppressed, and the blurring of the image can be suppressed. The laminate smoothness of the optical laminate 100 is, for example, 0.1 arcmin or more. Note that the laminate smoothness can be obtained by irradiating the target with illumination light and detecting the degree of reflection and transmission of each member constituting the target (laminated body).

[0053] The optical laminate 100 may have excellent durability. For example, the laminate smoothness of the optical laminate 100 after being placed in an 80°C environment for 500 hours is preferably 0.7 arcmin or less, more preferably 0.6 arcmin or less, and even more preferably 0.5 arcmin or less. Furthermore, the laminate smoothness of the optical laminate 100 after being placed in a -40°C environment for 500 hours is preferably 0.7 arcmin or less, more preferably 0.6 arcmin or less, and even more preferably 0.5 arcmin or less.

[0054] The optical laminate 100 may have high transmittance. For example, the optical laminate 100 may have a Y value of the luminous efficiency correction single transmittance of 90% or more, preferably 93% or more, more preferably 94% or more, and even more preferably 95% or more.

[0055] The second laminated portion 200 includes a reflective polarizing member 14 and an adhesive layer (e.g., an adhesive layer) disposed between the reflective polarizing member 14 and the second lens portion 24. The second laminated portion 200 further includes, for example, an absorptive polarizing member 28 disposed between the reflective polarizing member 14 and the second lens portion 24, from the viewpoint of improving visibility. The absorptive polarizing member 28 is laminated in front of the reflective polarizing member 14 via an adhesive layer (e.g., an adhesive layer) 44. The reflective axis of the reflective polarizing member 14 and the absorptive polarizing member 28 may be arranged substantially parallel to each other, and the transmission axis of the reflective polarizing member 14 and the transmission axis of the absorptive polarizing member 28 may be arranged substantially parallel to each other. By laminating via an adhesive layer, the reflective polarizing member 14 and the absorptive polarizing member 28 are fixed, and misalignment of the axial arrangement between the reflective axis and the absorptive axis (transmission axis and transmission axis) can be prevented. In addition, adverse effects due to an air layer that may be formed between the reflective polarizing member 14 and the absorptive polarizing member 28 can be suppressed.

[0056] The second laminated portion 200 further includes a second protective member 32 positioned behind the reflective polarizing member 14. The second protective member 32 is laminated to the reflective polarizing member 14 via an adhesive layer (e.g., a tack layer) 43. The second protective member 32 may be located on the outermost surface of the second laminated portion 200. The first protective member 31 and the second protective member 32 are positioned opposite each other with space in between. The second protective member, like the first protective member, may typically be a laminated film having a base material and a surface treatment layer. In this case, the surface treatment layer may be located on the outermost surface of the second laminated portion. Details of the second protective member can be described in the same way as for the first protective member. Specifically, the reflective properties and their effects, smoothness, thickness, and constituent materials of the second protective member can be described in the same way as for the first protective member.

[0057] In the example shown in Figure 2, the second laminated portion 200 further includes a third phase difference member 30 positioned between the absorptive polarizing member 28 and the second lens portion 24. The third phase difference member 30 is laminated to the absorptive polarizing member 28 via an adhesive layer (e.g., an adhesive layer) 45. The third phase difference member 30 is also laminated to the second lens portion 24 via an adhesive layer (e.g., an adhesive layer) 46, and the second laminated portion 200 is integrally provided with the second lens portion 24. The third phase difference member 30 includes, for example, a third λ / 4 member. The angle between the absorption axis of the absorptive polarizing member 28 and the lagging axis of the third λ / 4 member included in the third phase difference member 30 is, for example, 40° to 50°, may be 42° to 48°, or may be approximately 45°. By providing such a member, for example, reflection of ambient light from the second lens portion 16 side can be prevented. If the third phase difference member does not include any members other than the third λ / 4 member, the third phase difference member may correspond to the third λ / 4 member.

[0058] The above-described reflective polarizing member transmits polarized light parallel to its transmission axis (typically linearly polarized light) while maintaining its polarization state, and reflects light in other polarization states. Typically, the reflective polarizing member is composed of a multilayer film (sometimes referred to as a reflective polarizing film). In this case, the thickness of the reflective polarizing member is, for example, 10 μm to 150 μm, preferably 20 μm to 100 μm, and more preferably 30 μm to 60 μm.

[0059] Figure 3 is a schematic perspective view showing an example of a multilayer structure included in a reflective polarizing film. The multilayer structure 14a alternates between layers A, which have birefringence, and layers B, which have substantially no birefringence. The total number of layers constituting the multilayer structure may be 50 to 1000. For example, the refractive index nx in the x-axis direction of layer A is greater than the refractive index ny in the y-axis direction, and the refractive index nx in the x-axis direction and the refractive index ny in the y-axis direction of layer B are substantially the same, so the refractive index difference between layer A and layer B is large in the x-axis direction and substantially zero in the y-axis direction. As a result, the x-axis direction can be the reflection axis and the y-axis direction can be the transmission axis. The refractive index difference between layer A and layer B in the x-axis direction is preferably 0.2 to 0.3.

[0060] The above-mentioned layer A is typically composed of a material that exhibits birefringence upon stretching. Examples of such materials include naphthalenedicarboxylic acid polyester (e.g., polyethylene naphthalate), polycarbonate, and acrylic resins (e.g., polymethyl methacrylate). The above-mentioned layer B is typically composed of a material that does not substantially exhibit birefringence upon stretching. Examples of such materials include a copolyester of naphthalenedicarboxylic acid and terephthalic acid. The above multilayer structure can be formed by a combination of co-extrusion and stretching. For example, the materials constituting layer A and layer B are extruded and then multilayered (e.g., using a multiplier). The resulting multilayer laminate is then stretched. The x-axis direction in the illustrated example may correspond to the stretching direction.

[0061] Examples of commercially available reflective polarizing films include the product names "DBEF" and "APF" from 3M, and "APCF" from Nitto Denko.

[0062] The orthogonal transmittance (Tc) of the reflective polarizing member (reflective polarizing film) may be, for example, 0.01% to 3%. The single-element transmittance (Ts) of the reflective polarizing member (reflective polarizing film) may be, for example, 43% to 49%, preferably 45% to 47%. The degree of polarization (P) of the reflective polarizing member (reflective polarizing film) may be, for example, 92% to 99.99%.

[0063] The above orthogonal transmittance, single-element transmittance, and polarization degree can be measured, for example, using a UV-Vis spectrophotometer. The polarization degree P can be calculated using a UV-Vis spectrophotometer to measure the single-element transmittance Ts, parallel transmittance Tp, and orthogonal transmittance Tc, and then calculated from the obtained Tp and Tc using the following formula. Note that Ts, Tp, and Tc are Y values ​​measured using a 2-degree field of view (C light source) according to JIS Z 8701 and corrected for luminous efficiency. Polarization degree P(%)={(Tp-Tc) / (Tp+Tc)} 1 / 2 ×100

[0064] The above-mentioned absorption-type polarizing member may typically include a resin film containing a dichroic substance (sometimes referred to as an absorption-type polarizing film). The thickness of the absorption-type polarizing film is, for example, 1 μm or more and 20 μm or less, but may also be 2 μm or more and 15 μm or less, 12 μm or less, 10 μm or less, 8 μm or less, or 5 μm or less.

[0065] The above-mentioned absorption polarizing film may be made from a single layer of resin film, or it may be made using a laminate of two or more layers.

[0066] When manufactured from a single layer of resin film, for example, an absorption polarizing film can be obtained by subjecting a hydrophilic polymer film, such as a polyvinyl alcohol (PVA) film, a partially formalized PVA film, or a partially saponified ethylene-vinyl acetate copolymer film, to dyeing treatment with a dichroic substance such as iodine or a dichroic dye, and stretching treatment. Among these, an absorption polarizing film obtained by dyeing a PVA film with iodine and uniaxially stretching it is preferred.

[0067] The above iodine staining is carried out, for example, by immersing the PVA-based film in an iodine aqueous solution. The stretching ratio for the above uniaxial stretching is preferably 3 to 7 times. Stretching may be performed after the staining treatment, or during the staining process. Alternatively, staining may be performed after stretching. If necessary, the PVA-based film may be subjected to swelling, crosslinking, washing, drying, etc.

[0068] When using the above-mentioned laminate of two or more layers, examples of laminates include a laminate of a resin substrate and a PVA-based resin layer (PVA-based resin film) laminated on the resin substrate, or a laminate of a resin substrate and a PVA-based resin layer coated and formed on the resin substrate. An absorption polarizing film obtained using a laminate of a resin substrate and a PVA-based resin layer coated and formed on the resin substrate can be produced, for example, by applying a PVA-based resin solution to a resin substrate, drying it to form a PVA-based resin layer on the resin substrate, and obtaining a laminate of a resin substrate and a PVA-based resin layer; or by stretching and dyeing the laminate to make the PVA-based resin layer an absorption polarizing film. In this embodiment, preferably, a polyvinyl alcohol-based resin layer containing a halide and a polyvinyl alcohol-based resin is formed on one side of the resin substrate. Stretching typically includes immersing the laminate in an aqueous boric acid solution and stretching it. Furthermore, stretching may, if necessary, further include air-stretching the laminate at a high temperature (e.g., 95°C or higher) before stretching in the aqueous boric acid solution. In addition, in this embodiment, the laminate is preferably subjected to a drying shrinkage treatment in which it shrinks by 2% or more in the width direction by heating while being transported in the longitudinal direction. Typically, the manufacturing method of this embodiment includes applying an air-assisted stretching treatment, a dyeing treatment, a water-based stretching treatment, and a drying shrinkage treatment to the laminate in this order. By introducing auxiliary stretching, it is possible to increase the crystallinity of PVA even when PVA is coated on a thermoplastic resin, making it possible to achieve high optical properties. At the same time, by increasing the orientation of PVA in advance, it is possible to prevent problems such as a decrease in the orientation of PVA and dissolution when immersed in water in the subsequent dyeing and stretching processes, making it possible to achieve high optical properties. Furthermore, when the PVA-based resin layer is immersed in a liquid, the disorder of the orientation of polyvinyl alcohol molecules and the decrease in orientation can be suppressed compared to when the PVA-based resin layer does not contain halides. As a result, the optical properties of the absorption polarizing film obtained through processing steps in which the laminate is immersed in a liquid, such as dyeing and water-based stretching, can be improved. Furthermore, by shrinking the laminate in the width direction through a drying shrinkage treatment, the optical properties can be improved.The resulting resin substrate / absorbent polarizing film laminate may be used as is (i.e., the resin substrate may be used as a protective layer for the absorbent polarizing film), or an appropriate protective layer may be laminated on the peeled surface obtained by removing the resin substrate from the resin substrate / absorbent polarizing film laminate, or on the surface opposite to the peeled surface, depending on the purpose. Details of such a method for manufacturing an absorbent polarizing film are described, for example, in Japanese Patent Application Publication No. 2012-73580 and Japanese Patent No. 6470455. The entire contents of these publications are incorporated herein by reference.

[0069] The orthogonal transmittance (Tc) of the absorbing polarizing member (absorbing polarizing film) is preferably 0.5% or less, more preferably 0.1% or less, and even more preferably 0.05% or less. The single-layer transmittance (Ts) of the absorbing polarizing member (absorbing polarizing film) is, for example, 41.0% to 45.0%, and preferably 42.0% or more. The degree of polarization (P) of the absorbing polarizing member (absorbing polarizing film) is, for example, 99.0% to 99.997%, and preferably 99.9% or more.

[0070] The in-plane phase difference Re(550) of the third λ / 4 member described above is, for example, 100 nm to 190 nm, but may also be 110 nm to 180 nm, 130 nm to 160 nm, or 135 nm to 155 nm. The third λ / 4 member preferably exhibits an inverse dispersion wavelength characteristic in which the phase difference value increases with the wavelength of the measured light. The Re(450) / Re(550) of the third λ / 4 member is, for example, 0.75 or more and less than 1, and may also be 0.8 or more and 0.95 or less. The third λ / 4 member preferably exhibits a refractive index characteristic in which nx > ny ≥ nz. The Nz coefficient of the third λ / 4 member is preferably 0.9 to 3, more preferably 0.9 to 2.5, even more preferably 0.9 to 1.5, and particularly preferably 0.9 to 1.3.

[0071] The third λ / 4 member is formed from any suitable material that can satisfy the above characteristics. The third λ / 4 member may be, for example, a stretched resin film or an oriented solidified layer of a liquid crystal compound. The same description as for the second λ / 4 member can be applied to the third λ / 4 member which is composed of a stretched resin film or an oriented solidified layer of a liquid crystal compound. The second λ / 4 member and the third λ / 4 member may be the same in composition (e.g., forming material, thickness, optical properties, etc.) or they may be different in composition.

[0072] The thickness of the adhesive layer used for laminating each of the above components can be set to any appropriate thickness. Preferably, the thickness of each adhesive layer used for laminating each of the above components is 3 μm or more and 20 μm or less, but it may be 15 μm or less, 12 μm or less, or 7 μm or less. With such thicknesses, the degree of unevenness on the surface of the adhesive layer can be suppressed, and the laminated portion can have excellent smoothness. [Examples]

[0073] The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples. The thickness, phase difference value, and surface smoothness are values ​​measured by the measurement methods described below. Unless otherwise specified, "parts" and "%" are based on weight. <thickness> Thicknesses of 10 μm or less were measured using a scanning electron microscope (JEOL Ltd., product name "JSM-7100F"). Thicknesses exceeding 10 μm were measured using a digital micrometer (Anritsu Corporation, product name "KC-351C"). <Phase difference value> The phase difference values ​​at each wavelength at 23°C were measured using a Müller matrix polarimeter (manufactured by Axometrics, product name "Axoscan"). <Surface smoothness> Surface smoothness was measured using a scanning white light interferometer (Zygo, product name "NewView9000"). Specifically, the sample was placed on a measurement platform with vibration isolation, interference fringes were generated using a single white LED illumination, and an interference objective lens (1.4x) with a reference plane was scanned in the Z direction (thickness direction) to selectively acquire the smoothness (surface smoothness) of the outermost surface of the measurement target within a 12.4 mm square field of view. When the object of measurement was an adhesive layer, the adhesive layer was bonded to a micro-slide glass (manufactured by Matsunami Glass Industry Co., Ltd., product name "S200200"), and the smoothness of the exposed adhesive surface was measured. When the object of measurement was a film, a 5 μm thick, smooth acrylic adhesive layer was formed on the above glass, and the film to be measured was laminated to this adhesive surface, taking care to prevent foreign matter, air bubbles, or deformation streaks from entering. The smoothness of the surface opposite the adhesive layer was then measured. The surface smoothness of the 5 μm thick, smooth acrylic adhesive layer was 0.30 arcmin. For the analysis, the surface smoothness (unit: arcmin) was defined as twice the angular index "Slope magnitude RMS" (equivalent to 2σ).

[0074] [Example 1] (Fabrication of λ / 4 member) Polymerization was carried out using a batch polymerization apparatus consisting of two vertical reactors equipped with stirring blades and reflux condensers controlled to 100°C. The mixture consisted of 29.60 parts by mass (0.046 mol) of bis[9-(2-phenoxycarbonylethyl)fluoren-9-yl]methane, 29.21 parts by mass (0.200 mol) of isosorbide (ISB), 42.28 parts by mass (0.139 mol) of spiroglycol (SPG), 63.77 parts by mass (0.298 mol) of diphenyl carbonate (DPC), and 1.19 × 10⁻¹⁶ calcium acetate monohydrate as a catalyst. -2 Part of mass (6.78×10 -5A mol (mol) of polymer was added. After purging the reactor with reduced pressure using nitrogen, the reactor was heated with a heat transfer medium, and stirring was started when the internal temperature reached 100°C. Forty minutes after the start of heating, the internal temperature was raised to 220°C, and while controlling the pressure to maintain this temperature, the pressure was reduced to 13.3 kPa 90 minutes after reaching 220°C. The phenol vapor produced as a by-product of the polymerization reaction was directed to a reflux condenser at 100°C, and the monomer components contained in the phenol vapor were returned to the reactor. The uncondensed phenol vapor was directed to a condenser at 45°C and recovered. Nitrogen was introduced into the first reactor to restore the pressure to atmospheric pressure, and then the oligomerized reaction mixture in the first reactor was transferred to the second reactor. Next, heating and depressurization in the second reactor were started, and the internal temperature reached 240°C and the pressure 0.2 kPa in 50 minutes. Polymerization was then allowed to proceed until the predetermined stirring power was reached. Once the predetermined power level was reached, nitrogen was introduced into the reactor to restore pressure, and the resulting polyester carbonate resin was extruded into water. The strands were then cut to obtain pellets.

[0075] The obtained polyester carbonate resin (pellets) was vacuum-dried at 80°C for 5 hours. Then, a long resin film with a thickness of 135 μm was produced using a film-making apparatus equipped with a single-screw extruder (manufactured by Toshiba Machine Co., Ltd., cylinder setting temperature: 250°C), a T-die (width 200 mm, setting temperature: 250°C), a chill roll (setting temperature: 120~130°C), and a winding machine. The obtained long resin film was stretched in the width direction at a stretching temperature of 143°C and a stretching ratio of 2.8 times to obtain a stretched film with a thickness of 47 μm. The Re(550) of the obtained stretched film was 143 nm, the Re(450) / Re(550) was 0.86, and the Nz coefficient was 1.12.

[0076] (Formation of a positive C plate) A liquid crystal coating solution was prepared by dissolving 20 parts by weight of a side-chain liquid crystal polymer represented by the following chemical formula (1) (the numbers 65 and 35 in the formula indicate the mole percent of monomer units and are conveniently represented as a block polymer: weight-average molecular weight 5000), 80 parts by weight of a polymerizable liquid crystal exhibiting a nematic liquid crystal phase (BASF: trade name Paliocolor LC242), and 5 parts by weight of a photopolymerization initiator (Ciba Specialty Chemicals: trade name Irgacure 907) in 200 parts by weight of cyclopentanone. The coating solution was then applied to a vertically aligned PET substrate using a bar coater, and the liquid crystal was aligned by heating and drying at 80°C for 4 minutes. By irradiating this liquid crystal layer with ultraviolet light and curing the liquid crystal layer, a positive C plate with a thickness of 4 μm and an Rth(550) of -100 nm was formed on the substrate. [ka]

[0077] (Fabrication of protective components) An acrylic film (40 μm thick, surface smoothness 0.45 arcmin) having a lactone ring structure is coated with the following hard coat layer forming material and heated at 90°C for 1 minute. After heating, the coated layer is exposed to a high-pressure mercury lamp with an integrated light intensity of 300 mJ / cm². 2 An acrylic film (44 μm thick, with a surface smoothness of 0.4 arcmin on the hard coat side) was fabricated by curing the coated layer with ultraviolet light, forming a hard coat layer with a thickness of 4 μm. Next, the anti-reflective coating liquid A described below was applied to the hard coat layer using a wire bar, and the applied coating liquid was heated at 80°C for 1 minute to dry and form a coating film. After drying, the coating film was exposed to a high-pressure mercury lamp with an integrated light intensity of 300 mJ / cm². 2 The coating was cured by irradiating it with ultraviolet light to form an anti-reflective layer A with a thickness of 140 nm. Next, the anti-reflective coating liquid B described below was applied to the anti-reflective layer A using a wire bar, and the applied coating liquid was heated at 80°C for 1 minute to dry and form a coating film. After drying, the coating film was exposed to a high-pressure mercury lamp with an integrated light intensity of 300 mJ / cm². 2The coating was cured by irradiating it with ultraviolet light to form an anti-reflective layer B with a thickness of 105 nm. In this way, a protective member (thickness 44 μm, surface smoothness of 0.4 arcmin on the anti-reflective layer side) was obtained.

[0078] (Hard coat layer forming material) A hard coat layer forming material was prepared by mixing 50 parts of urethane acrylic oligomer (manufactured by Shin Nakamura Chemical Co., Ltd., "NK Oligo UA-53H"), 30 parts of polyfunctional acrylate mainly composed of pentaerythritol triacrylate (manufactured by Osaka Organic Chemical Industry Co., Ltd., product name "Viscote #300"), 20 parts of 4-hydroxybutyl acrylate (manufactured by Osaka Organic Chemical Industry Co., Ltd.), 1 part of leveling agent (manufactured by DIC Corporation, "GRANDIC PC4100"), and 3 parts of photopolymerization initiator (manufactured by Ciba Japan, "Irgacure 907"), and diluting with methyl isobutyl ketone to a solid content concentration of 50%.

[0079] (Anti-reflective coating liquid A) 100 parts by weight of polyfunctional acrylate (manufactured by Arakawa Chemical Industries, Ltd., trade name "Opstar KZ6728", solids content 20% by weight), 3 parts by weight of leveling agent (manufactured by DIC, "GRANDIC PC4100"), and 3 parts by weight of photopolymerization initiator (manufactured by BASF, trade name "OMNIRAD907", solids content 100% by weight) were mixed. Butyl acetate was used as a diluent to adjust the solids content of the mixture to 12% by weight, and the mixture was stirred to prepare coating solution A for forming an anti-reflective layer.

[0080] (Coating liquid B for forming an anti-reflective layer) A mixture was prepared by combining 100 parts by weight of a polyfunctional acrylate mainly composed of pentaerythritol triacrylate (manufactured by Osaka Organic Chemical Industry Co., Ltd., product name "Viscoat #300", solid content 100% by weight), 150 parts by weight of hollow nanosilica particles (manufactured by JGC Catalysts & Chemicals Co., Ltd., product name "Thru-Ria 5320", solid content 20% by weight, weight-average particle size 75 nm), 50 parts by weight of solid nanosilica particles (manufactured by Nissan Chemical Industries, Ltd., product name "MEK-2140Z-AC", solid content 30% by weight, weight-average particle size 10 nm), 12 parts by weight of a fluorine-containing additive (manufactured by Shin-Etsu Chemical Co., Ltd., product name "KY-1203", solid content 20% by weight), and 3 parts by weight of a photopolymerization initiator (manufactured by BASF, product name "OMNIRAD907", solid content 100% by weight). To this mixture, a mixed solvent consisting of TBA (tert-butyl alcohol), MIBK (methyl isobutyl ketone), and PMA (propylene glycol monomethyl ether acetate) in a weight ratio of 60:25:15 was added as a diluent to prepare coating solution B for anti-reflective layer formation. The mixture was then stirred to achieve a total solid content of 4% by weight.

[0081] (Preparation of adhesive) An adhesive was prepared by mixing 62 parts by weight of hydroxyethyl acrylamide (manufactured by Kojinsha, trade name "HEAA"), 25 parts by weight of acryloylmorpholine (manufactured by Kojinsha, trade name "ACMO"), 7 parts by weight of PEG400# diacrylate (manufactured by Kyoeisha Chemical Co., Ltd., trade name "Light Acrylate 9EG-A"), 3 parts by weight of BASF's trade name "Irgacure 907", and 3 parts by weight of Nippon Kayaku's trade name "KAYACURE DETX-S" for 60 minutes.

[0082] (Fabrication of optical stacks) The above-mentioned adhesive was applied to the above-mentioned λ / 4 member (stretched film) so that the thickness after curing was 0.6 μm, and the above-mentioned positive C plate was bonded to it to obtain a phase difference member. The protective member (an acrylic film with a hard coat layer and an anti-reflective layer formed on it) was bonded to the λ / 4 member side of the obtained phase difference member via an adhesive layer with a thickness of 12 μm and a surface smoothness of 0.25 arcmin. Here, the acrylic film of the protective member was bonded so that it was positioned on the λ / 4 member side. Next, an adhesive layer with a thickness of 12 μm and a surface smoothness of 0.25 arcmin was formed on the positive C plate side of the phase difference member to obtain an optical laminate.

[0083] [Example 2] An optical laminate was obtained in the same manner as in Example 1, except that an adhesive was applied to the λ / 4 member so that the thickness after curing was 0.9 μm, and then a positive C plate was bonded to it.

[0084] [Example 3] An optical laminate was obtained in the same manner as in Example 1, except that an adhesive was applied to the λ / 4 member so that the thickness after curing was 1.3 μm, and then a positive C plate was bonded to it.

[0085] [Comparative Example 1] An optical laminate was obtained in the same manner as in Example 1, except that an adhesive was applied to the λ / 4 member so that the thickness after curing was 1.5 μm, and a positive C plate was bonded to it.

[0086] [Comparative Example 2] An optical laminate was obtained in the same manner as in Example 1, except that an adhesive was applied to the λ / 4 member so that the thickness after curing was 1.9 μm, and then a positive C plate was bonded to it.

[0087] [Comparative Example 3] An optical laminate was obtained in the same manner as in Example 1, except that a tack (5 μm thick) was used instead of adhesive when bonding the positive C plate to the λ / 4 member.

[0088] The optical laminates obtained in the examples and comparative examples were evaluated as follows. The evaluation results are shown in Table 1. (1) Laminate smoothness The smoothness of the laminate was measured using a phase-shift laser interferometer (Zygo, product name "DynaFiz"). Specifically, the optical laminate was laminated onto a micro-slide glass (Matsunami Glass Industry Co., Ltd., product name "S200200") to prevent the inclusion of foreign matter, air bubbles, or deformation streaks. Next, degassing was performed using a pressurized degasser (autoclave) to remove the effects of minute air bubbles. The degassing conditions were 50°C, 0.5 MPa, and 30 minutes. After degassing, the sample was allowed to cool at room temperature for 30 minutes or more to obtain the measurement sample. The sample was placed on a vibration-isolating measuring table, and a single-wavelength (wavelength 633 nm) laser was used to interfere with a standard instrument with guaranteed flatness, and the relative displacement within a predetermined area (a circle with a diameter of 30 mm) was measured. For the analysis, the "Slope magnitude RMS," an angular index obtained by extracting frequency values ​​from 0.1 / mm to 1 / mm, was doubled (corresponding to 2σ), and this value was defined as the smoothness of the laminate (unit: arcmin). (2) Appearance The appearance (transmitted light through the lens) of the optically laminated structure was evaluated using an optical lens (Thorabs, product name "LA1145") and a point light source (Hamamatsu Photonics, model number "L8425-01"). Specifically, a 45mm diameter circular optical laminate was laminated to the flat side of the optical lens to prevent foreign matter, air bubbles, or deformation streaks from entering the surface. Next, degassing was performed using a pressurized degasser (autoclave) to remove the effects of minute air bubbles. The degassing conditions were 50°C, 0.5 MPa, and 30 minutes. After degassing, the sample was allowed to cool at room temperature for 30 minutes or more to obtain the measurement sample. A point light source, an optical lens (measurement sample), and a screen were set up in this order, and the light from the point light source was projected onto the screen through the optical lens, and its appearance was evaluated. Here, the optical lens was held in place by a holder so that the light from the point light source entered from the convex side of the lens. The distance from the point light source to the screen was 1050 mm, and the distance from the optical lens to the screen was 130 mm. The visual appearance was evaluated by 10 evaluators who visually observed the light projected onto the screen through an optical lens and judged the presence or absence of wrinkles and undulations. The number of evaluators who judged that there were no wrinkles or undulations is shown in Table 1. (3)Durability A thermal shock test was conducted on the optical laminate using a thermal shock device (manufactured by ESPEC, product name "TSA-303EL-W"). An optical laminate, cut into a 45mm diameter circle using a laser cutting machine, was bonded to a glass plate. This was then placed in a -40°C environment for 0.5 hours, followed by a 85°C environment for 0.5 hours. The time taken for both heating and cooling was kept to within 6 minutes. After repeating this operation a total of 100 times, the appearance of the optical laminate was visually inspected to check for cracks and delamination. (Evaluation Criteria) • Good: No cracks or peeling observed. • Defect: Cracks and / or peeling are observed. (4) Transmittance The transmittance Ts of the optical laminate was measured using a UV-Vis spectrophotometer (JASCO Corporation, V-7100). Ts is the Y value after measuring according to JIS Z 8701's 2-degree field of view (C light source) and correcting for luminous sensitivity. The optical laminate was measured without being bonded to a substrate such as glass.

[0089] [Table 1]

[0090] In the durability evaluation, in Comparative Example 3, cracks were observed in the positive C plate, which was thinner than the λ / 4 member. The cracks were 10 mm or longer, originated from the edge of the sample, and were visible to the naked eye. On the other hand, when the optical laminate of Example 1 was subjected to the above evaluations after being placed in an 80°C temperature environment for 500 hours or in a -40°C temperature environment for 500 hours, the same results as when no such temperature treatment was applied (results shown in Table 1) were obtained.

[0091] The present invention is not limited to the embodiments described above, and various modifications are possible. For example, the configurations shown in the embodiments above can be replaced with configurations that are substantially the same, configurations that produce the same effects, or configurations that can achieve the same purpose. [Industrial applicability]

[0092] An optical laminate according to an embodiment of the present invention can be used, for example, in a display device such as a VR goggle. [Explanation of symbols]

[0093] 2 Display system, 4 Lens section, 12 Display element, 14 Reflective polarizing member, 16 First lens section, 18 Half mirror, 20 First phase difference member, 22 Second phase difference member, 24 Second lens section, 28 Absorbing polarizing member, 30 Third phase difference member, 31 First protective member, 32 Second protective member, 41 Adhesive layer, 42 Adhesive layer, 43 Adhesive layer, 44 Adhesive layer, 45 Adhesive layer, 46 Adhesive layer, 50 Adhesive layer, 100 First laminated section (optical laminate), 200 Second laminated section.

Claims

1. An optical laminate comprising a polarizing member, a first λ / 4 member, a second λ / 4 member, and an optical component set having a reflective polarizing member, Each component included in the optical component set is arranged such that light emitted forward from the display element passes through the polarizing member, the first λ / 4 member, and the optical laminate in that order, is reflected by the reflective polarizing member, and then passes through the optical laminate and is reflected forward again, passing through the optical laminate and the reflective polarizing member in that order. The optical laminate comprises a laminated film having a substrate and a surface treatment layer, and a phase difference member. The substrate of the laminated film and the phase difference member are arranged adjacent to each other. The phase difference member includes a first phase difference layer, an adhesive layer, and a second phase difference layer in this order. The aforementioned adhesive layer is a cured resin layer, The thickness of the adhesive layer is 0.5 μm or more and 1.3 μm or less. The first phase difference layer corresponds to the second λ / 4 member, Optical component set.

2. The optical component set according to claim 1, wherein the laminated smoothness of the optical laminate is 0.7 arcmin or less.

3. The optical component set according to claim 1, wherein the surface smoothness of the laminated film is 0.5 arcmin or less.

4. The optical component set according to claim 1, wherein the substrate of the laminated film comprises a (meth)acrylic resin.

5. The optical component set according to claim 1, wherein the surface treatment layer of the laminated film has an anti-reflective function.

6. The optical component set according to claim 1, wherein the first phase difference layer exhibits refractive index characteristics nx > ny ≥ nz and satisfies the relationship Re(450) < Re(550) < Re(650): Here, Re(450) represents the in-plane phase difference measured with light of a wavelength of 450 nm at 23°C, Re(550) represents the in-plane phase difference measured with light of a wavelength of 550 nm at 23°C, and Re(650) represents the in-plane phase difference measured with light of a wavelength of 650 nm at 23°C.

7. The optical component set according to claim 1, wherein the second phase difference layer exhibits refractive index characteristics nz > nx ≥ ny.

8. The optical component set according to claim 1, wherein the Y value of the luminous efficiency correction single transmittance of the optical laminate is 93% or more.

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