Display system, display method, display body, and method for manufacturing a display body

Abstract

To provide a display system capable of achieving weight reduction and high definition of a VR goggle.SOLUTION: A display system displays an image to a user. The display system comprises: a display element having a display surface that emits light representing the image forward via a polarization member; a reflection portion that is disposed in front of the display element, includes a reflection type polarization member, and reflects the light emitted from the display element; a first lens portion disposed on an optical path between the display element and the reflection portion; a half mirror that is disposed between the display element and the first lens portion, transmits the light emitted from the display element, and reflects the light reflected by the reflection portion toward the reflection portion; a first λ / 4 member disposed on an optical path between the display element and the half mirror; and a second λ / 4 member disposed on an optical path between the half mirror and the reflection portion. A slow axis of the first λ / 4 member and a slow axis of the second λ / 4 member are arranged so as to be substantially parallel to each other.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a display system, a display method, a display body, and a method for manufacturing the display body.

Background Art

[0002] Image display devices typified 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 started to be commercialized. Since VR goggles are being considered for use in various scenarios, weight reduction, high definition, 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 a display system that can achieve weight reduction and high definition of VR goggles.

Means for Solving the Problems

[0006] According to one aspect of the present invention, the following display systems [1] to [7] are provided. [1] A display system that displays images to a user, A display element having a display surface that emits light representing an image forward via a polarizing member, A reflective portion is positioned in front of the above-mentioned display element and includes a reflective polarizing member, which reflects light emitted from the above-mentioned display element. A first lens portion is arranged in the optical path between the above-mentioned display element and the above-mentioned reflective portion, A half-mirror is positioned between the display element and the first lens section, which transmits light emitted from the display element and reflects the light reflected by the reflecting section back towards the reflecting section. A first λ / 4 member is arranged in the optical path between the above-mentioned display element and the above-mentioned half-mirror, A second λ / 4 member is positioned in the optical path between the half-mirror and the reflecting part, Equipped with, A display system in which the slow axis of the first λ / 4 member and the slow axis of the second λ / 4 member are arranged to be substantially parallel to each other. [2] The display system according to [1], wherein the polarization direction of the light emitted through the polarizing member and the reflection axis of the reflective polarizing member are substantially orthogonal to each other. [3] The angle between the absorption axis of the polarization member included in the display element and the slow axis of the first λ / 4 member is 40° to 50°. The display system according to [1] or [2], wherein the angle between the absorption axis of the polarizing member included in the display element and the slow axis of the second λ / 4 member is 40° to 50°. [4] The display system according to any one of [1] to [3], wherein the first lens portion and the half mirror are integrated. [5] A display system according to any one of [1] to [4], comprising a second lens portion positioned in front of the reflective portion. [6] The display system according to any one of [1] to [5], wherein the reflective portion includes an absorbing polarizing member positioned in front of the reflective polarizing member. [7] The display system according to [6], wherein the reflection axis of the reflective polarizing member and the absorption axis of the absorptive polarizing member are arranged substantially parallel to each other.

[0007] According to another aspect of the present invention, the following display methods [8] to [9] are provided. [8] The step of passing the light representing the image emitted through the polarizing member through the first λ / 4 member, The steps include passing the light that has passed through the first λ / 4 member through the half mirror and the first lens section, The steps include passing the light that has passed through the above-mentioned half-mirror and the above-mentioned first lens portion through a second λ / 4 member, The steps include: reflecting the light that has passed through the second λ / 4 member toward the half mirror using a reflective section that includes a reflective polarizing member; The step includes making the light reflected by the above-mentioned reflective portion and the above-mentioned half-mirror passable through the above-mentioned reflective portion by the second λ / 4 member, The slow axis of the first λ / 4 member and the slow axis of the second λ / 4 member are arranged to be substantially parallel to each other. Display method. [9] The display method according to [8], wherein the polarization direction of the light emitted through the polarizing member and the reflection axis of the reflective polarizing member are substantially orthogonal to each other.

[0008] According to another aspect of the present invention, a display body comprising the display system described in any of [1] to [7] above is provided. In yet another aspect of the present invention, a method for manufacturing a display body comprising the display system described in any of [1] to [7] above is provided. [Effects of the Invention]

[0009] According to the display system of the embodiment of the present invention, it is possible to achieve lighter weight and higher resolution for VR goggles. [Brief explanation of the drawing]

[0010] [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]It is a schematic diagram for explaining the propagation of light and the polarization state in a display system according to one embodiment of the present invention.

Embodiments for Carrying Out the Invention

[0011] Hereinafter, embodiments of the present invention will be described with reference to the drawings, but the present invention is not limited to these embodiments. Also, for the purpose of making the explanation clearer, the drawings may schematically show the width, thickness, shape, etc. of each part as compared with the embodiments, but this is merely an example and does not limit the interpretation of the present invention.

[0012] (Definitions of Terms and Symbols) The definitions of terms and symbols in this specification are as follows. (1) Refractive Index (nx, ny, nz) "nx" is the refractive index in the direction where the in-plane refractive index is maximum (i.e., the slow axis direction), "ny" is the refractive index in the direction orthogonal to the slow axis in the plane (i.e., the fast 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 λ nm at 23°C. For example, "Re(550)" is the in-plane phase difference measured with light of wavelength 550 nm at 23°C. Re(λ) is obtained by the formula: Re(λ)=(nx - ny)×d when the thickness of the layer (film) is d (nm). (3) Phase Difference in the Thickness Direction (Rth) "Rth(λ)" is the phase difference in the thickness direction measured with light of wavelength λ nm at 23°C. For example, "Rth(550)" is the phase difference in the thickness direction measured with light of wavelength 550 nm at 23°C. Rth(λ) is obtained by the formula: Rth(λ)=(nx - nz)×d when the thickness of the layer (film) is d (nm). (4) Nz Coefficient The Nz coefficient is obtained by Nz = Rth / Re. (5) Angle In this specification, when an angle is mentioned, unless otherwise specified, the angle includes both clockwise and counterclockwise directions with respect to the reference direction. For example, "45°" means ±45°. Also in this specification, "approximately parallel" includes the case where the angle is 0°±5°, preferably 0°±3°, more preferably 0°±1°, and even more preferably 0°±0.5°, and "approximately orthogonal" includes the case where the angle is 90°±5°, preferably 90°±3°, more preferably 90°±1°, and even more preferably 90°±0.5°.

[0013] Figure 1 is a schematic diagram showing the general configuration of a display system according to one embodiment of the present invention. Figure 1 schematically illustrates the arrangement and shape of each component of the display system 2. The display system 2 comprises a display element 12, a reflecting section 14 including a reflective polarizing member, a first lens section 16, a half mirror 18, a first phase difference member 20, a second phase difference member 22, and a second lens section 24. The reflecting section 14 is positioned in front of the display element 12 on the display surface 12a side and can reflect light emitted from the display element 12. The first lens section 16 is positioned in the optical path between the display element 12 and the reflecting section 14, and the half mirror 18 is positioned between the display element 12 and the first lens section 16. The first phase difference member 20 is positioned in the optical path between the display element 12 and the half mirror 18, and the second phase difference member 22 is positioned in the optical path between the half mirror 18 and the reflecting section 14.

[0014] The components positioned in front of the half-mirror (in the illustrated example, the half-mirror 18, the first lens section 16, the second phase difference member 22, the reflecting section 14, and the second lens section 24) are sometimes collectively referred to as the lens section (lens section 4).

[0015] 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. 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 first linearly polarized light.

[0016] The first retardation member 20 is a λ / 4 member that can convert the first linearly polarized light incident on the first retardation member 20 into the first circularly polarized light (hereinafter, the first retardation member may be referred to as the first λ / 4 member). Note that the first retardation member 20 may be provided integrally with the display element 12.

[0017] The in-plane retardation Re(550) of the first retardation member 20 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.

[0018] The first retardation member 20 preferably exhibits an inverse dispersion wavelength characteristic in which the retardation value increases according to the wavelength of the measurement light. Re(450) / Re(550) of the first retardation member 20 is, for example, less than 1, may be 0.95 or less, may further be less than 0.90, or may further be 0.85 or less. Re(450) / Re(550) of the first retardation member 20 is, for example, 0.75 or more.

[0019] In one embodiment, the first retardation member 20 satisfies all of Re(400) / Re(550) < 0.85, Re(650) / Re(550) > 1.03, and Re(750) / Re(550) > 1.05. The first retardation member 20 preferably satisfies at least one selected from 0.65 < Re(400) / Re(550) < 0.80 (preferably, 0.7 < Re(400) / Re(550) < 0.75), 1.0 < Re(650) / Re(550) < 1.25 (preferably, 1.05 < Re(650) / Re(550) < 1.20), and 1.05 < Re(750) / Re(550) < 1.40 (preferably, 1.08 < Re(750) / Re(550) < 1.36), more preferably satisfies at least two, and even more preferably satisfies all.

[0020] The first retardation member 20 preferably exhibits 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 that does not impair the effects of the present invention, ny < nz may occur. The Nz coefficient of the first retardation member 20 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.

[0021] The first retardation member 20 is formed of any suitable material that can satisfy the above characteristics. The first retardation member 20 can be, for example, a stretched film of a resin film or an alignment cured layer of a liquid crystal compound.

[0022] Examples of the resin contained in the 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, acrylic resins, and the like. These resins may be used alone or in combination (for example, blended or copolymerized). When the first retardation member 20 exhibits an inverse dispersion wavelength characteristic, a resin film containing a polycarbonate resin or a polyester carbonate resin (hereinafter sometimes simply referred to as a polycarbonate resin) can be preferably used.

[0023] As the polycarbonate resin described above, any suitable polycarbonate resin can be used as long as the effects of the present invention are obtained. 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 first phase difference member and methods for forming the first phase difference member are described, for example, in Japanese Patent Publication No. 2014-10291, Japanese Patent Publication No. 2014-26266, Japanese Patent Publication No. 2015-212816, Japanese Patent Publication No. 2015-212817, and Japanese Patent Publication No. 2015-212818, and the descriptions in these publications are incorporated herein by reference.

[0024] The thickness of the first phase difference member 20, which is composed of a stretched resin film, is, for example, 10 μm to 100 μm, preferably 10 μm to 70 μm, more preferably 10 μm to 40 μm, and even more preferably 20 μm to 30 μm.

[0025] 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 first phase difference member, typically, rod-shaped liquid crystal compounds are oriented in a state where they are aligned in the slow phase axis direction of the first phase difference 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.

[0026] 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.

[0027] 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.

[0028] 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.

[0029] 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.

[0030] The thickness of the first phase difference member 20, 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.

[0031] The half-mirror 18 transmits light emitted from the display element 12 and reflects the light reflected by the reflecting part 14 back towards the reflecting part 14. The half-mirror 18 is integrally provided with the first lens part 16.

[0032] The second phase difference member 22 is a λ / 4 member that can transmit light reflected by the reflecting portion 14 and the half mirror 18 through the reflecting portion 14, which includes a reflective polarizing member (hereinafter, the second phase difference member may be referred to as the second λ / 4 member). The second phase difference member 22 may be provided integrally with the first lens portion 16.

[0033] The in-plane phase difference Re(550) of the second phase difference member 22 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.

[0034] The second phase difference member 22 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 second phase difference member 22 is, for example, less than 1, may be 0.95 or less, and may be less than 0.90, or even less than 0.85. The Re(450) / Re(550) of the second phase difference member 22 is, for example, 0.75 or more.

[0035] In one embodiment, the second retardation member 22 satisfies all of Re(400) / Re(550) < 0.85, Re(650) / Re(550) > 1.03, and Re(750) / Re(550) > 1.05. The second retardation member 22 preferably satisfies at least one selected from 0.65 < Re(400) / Re(550) < 0.80 (preferably, 0.7 < Re(400) / Re(550) < 0.75), 1.0 < Re(650) / Re(550) < 1.25 (preferably, 1.05 < Re(650) / Re(550) < 1.20), and 1.05 < Re(750) / Re(550) < 1.40 (preferably, 1.08 < Re(750) / Re(550) < 1.36), more preferably satisfies at least two, and still more preferably satisfies all of them.

[0036] The second retardation member 22 preferably exhibits 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 that does not impair the effects of the present invention, ny < nz may occur. The Nz coefficient of the second retardation member 22 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.

[0037] The second retardation member 22 is formed of any suitable material that can satisfy the above characteristics. The second retardation member 22 can be, for example, a stretched film of a resin film or an alignment cured layer of a liquid crystal compound. Regarding the second retardation member 22 composed of a stretched film of a resin film or an alignment cured layer of a liquid crystal compound, the same explanation as that for the first retardation member 20 can be applied. The first retardation member 20 and the second retardation member 22 may be members having the same configuration (forming material, thickness, optical characteristics, etc.) or members having different configurations.

[0038] The reflective portion 14 may include an absorptive polarizing member (typically, an absorptive polarizing film). In this case, the absorptive polarizing member may be positioned in front of the reflective polarizing member (closer to the eye). The reflective axis of the reflective polarizing member and the absorptive polarizing member may be positioned substantially parallel to each other. For example, the reflective polarizing member and the absorptive polarizing member may be laminated with an adhesive layer in between, and the reflective portion 14 may include a laminate having the reflective polarizing member and the absorptive polarizing member.

[0039] The above-mentioned reflective polarizing member transmits polarized light parallel to its transmission axis (typically linearly polarized light) while maintaining its polarization state, and can reflect light in other polarization states. The orthogonal transmittance (Tc) of the reflective polarizing member may be, for example, 0.01% to 3%. The single-layer transmittance (Ts) of the reflective polarizing member may be, for example, 43% to 49%, preferably 45% to 47%. The degree of polarization (P) of the reflective polarizing member may be, for example, 92% to 99.99%. The reflective polarizing member is typically composed of a multilayer film (sometimes referred to as a reflective polarizing film). Examples of commercially available reflective polarizing films include the product names "DBEF" and "APF" from 3M, and "APCF" from Nitto Denko. The above-mentioned absorbing polarizing member is typically composed of a resin film containing a dichroic substance (sometimes referred to as an absorbing polarizing film).

[0040] Typically, the slow axis of the first phase difference member 20 and the slow axis of the second phase difference member 22 are arranged approximately parallel to each other. Also, the absorption axis of the polarizing member included in the display element 12 and the reflection axis of the reflective polarizing member included in the reflection section 14 can be arranged approximately parallel to each other (in other words, the polarization direction of the light emitted through the polarizing member included in the display element 12 and the reflection axis of the reflective polarizing member included in the reflection section 14 can be approximately orthogonal to each other). The angle between the absorption axis of the polarizing member included in the display element 12 and the slow axis of the first phase difference member 20 is, for example, 40° to 50°, may be 42° to 48°, or may be approximately 45°. The angle between the absorption axis of the polarizing member included in the display element 12 and the slow axis of the second phase difference member 22 is, for example, 40° to 50°, may be 42° to 48°, or may be approximately 45°. By adjusting the axial relationship of each member to this state, the coloration of transmitted light can be suitably suppressed.

[0041] Hereinafter, a display system in one embodiment of the present invention will be described with reference to Figures 1 and 2. Figure 2(a) is a schematic diagram illustrating the propagation of light in the display system, and Figure 2(b) is a schematic diagram illustrating the change in the polarization state of light due to transmission through or reflection by each component in the display system. In Figure 2, the solid arrow attached to the display element 12 indicates the absorption axis direction of the polarizing member included in the display element 12, the arrows attached to the first phase difference member 20 and the second phase difference member 22 indicate the slow phase axis direction, the solid arrow attached to the reflective polarizing member 14a included in the reflecting section 14 indicates the reflection axis direction, and the dotted arrows indicate the transmission axis direction of each polarizing member.

[0042] Light L emitted from the display element 12 as first linearly polarized light via the polarizing member is converted into first circularly polarized light by the first λ / 4 member 20. The first circularly polarized light passes through the half mirror 18 and the first lens portion 16 (not shown in Figure 2) and is converted into second linearly polarized light whose polarization direction is orthogonal to that of the first linearly polarized light by the second λ / 4 member 22. The polarization direction of the second linearly polarized light is in the same direction (approximately parallel) as the reflection axis of the reflective polarizing member 14a included in the reflection portion 14. Therefore, the second linearly polarized light incident on the reflection portion 14 is reflected toward the half mirror 18 by the reflective polarizing member 14a.

[0043] The second linearly polarized light reflected by the reflecting section 14 is converted into a second circularly polarized light by the second λ / 4 member 22. The rotation direction of the second circularly polarized light is the same as the rotation direction of the first circularly polarized light. The second circularly polarized light emitted from the second λ / 4 member 22 passes through the first lens section 16 and is reflected by the half mirror 18, where it is converted into a third circularly polarized light that rotates in the opposite direction to the second circularly polarized light. The third circularly polarized light reflected by the half mirror 18 passes through the first lens section 16 and is converted into a third linearly polarized light by the second λ / 4 member 22. The polarization direction of the third linearly polarized light is perpendicular to the polarization direction of the second linearly polarized light and is in the same direction (approximately parallel) to the transmission axis of the reflective polarizing member 14a. Therefore, the third linearly polarized light can be transmitted through the reflective polarizing member 14a. Furthermore, although not shown in the figures, if the reflective portion includes an absorbing polarizing member, its absorption axis is positioned to be approximately parallel to the reflection axis of the reflective polarizing member 14a. As a result, the third linearly polarized light that passes through the reflective polarizing member 14a can pass through the absorbing polarizing member as is.

[0044] Light that has passed through the reflective section 14 passes through the second lens section 24 and enters the user's eye 26.

[0045] In Figure 2, when viewed from the display element 12 side, the lagging axes of the first phase difference member 20 and the second phase difference member 22 are arranged at a 45° counterclockwise angle with respect to the absorption axis of the polarizing member included in the display element 12. However, the same explanation can be applied even if they are arranged at a 45° clockwise angle. [Examples]

[0046] The present invention will be specifically described below with reference to examples, but the present invention is not limited in any way to these examples. The test and evaluation methods in the examples are as follows. When "parts" is written, it means "parts by weight" unless otherwise specified, and when "%" is written, it means "percent by weight" unless otherwise specified.

[0047] (1) 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"). (2) In-plane phase difference Re(λ) Samples were prepared by cutting out the center and both ends of a λ / 4 member in the width direction into squares measuring 50 mm in width and 50 mm in length, with one side parallel to the width direction of the member. The in-plane phase difference at each wavelength at 23°C was measured using a Müller matrix polarimeter (Axometrics, product name "Axoscan"). (3) Transmittance and polarization of a single unit The single-layer transmittance Ts, parallel transmittance Tp, and orthogonal transmittance Tc of polarizing films or laminates were measured using a spectrophotometer (Otsuka Electronics Co., Ltd., "LPF-200"). These Ts, Tp, and Tc values ​​are Y values ​​obtained by measuring under a 2-degree field of view (C light source) according to JIS Z8701 and correcting for luminous sensitivity. From the obtained Tp and Tc values, the polarization degree of the polarizing film was determined using the following formula. Degree of polarization (%)={(Tp-Tc) / (Tp+Tc)} 1 / 2 ×100 (4) Hue Light from a light source is incident on the λ / 4 member side surface of the laminates prepared in the examples and comparative examples, and the parallel hue (a) of the light emitted from the polarizing film side surface is determined. * value, b * The value was measured using a spectrophotometer (Otsuka Electronics Co., Ltd., "LPF-200").

[0048] [Manufacturing Example 1: Fabrication of λ / 4 component] A batch polymerization apparatus consisting of two vertical reactors equipped with stirring blades and reflux condensers controlled to 100°C was used to prepare the reactor. The mixture contained 29.60 parts by weight (0.046 mol) of bis[9-(2-phenoxycarbonylethyl)fluoren-9-yl]methane, 29.21 parts by weight (0.200 mol) of isosorbide (ISB), 42.28 parts by weight (0.139 mol) of spiroglycol (SPG), 63.77 parts by weight (0.298 mol) of diphenyl carbonate (DPC), and 1.19 × 10⁻¹⁶ calcium acetate monohydrate as a catalyst. -2 Weight part (6.78×10 -5 A 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. The obtained polyester carbonate resin (pellets) was vacuum-dried at 80°C for 5 hours. Then, a long resin film with a thickness of 130 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 140°C and a stretching ratio of 2.7 times. This resulted in a phase difference film (λ / 4 member) with a thickness of 47 μm, a Re(590) of 143 nm, and an Nz coefficient of 1.2. The Re(450) / Re(550) of the λ / 4 member was 0.856.

[0049] [Manufacturing Example 2: Production of Polarizing Film] As a thermoplastic resin substrate, an amorphous isophthalic copolymer polyethylene terephthalate film (thickness: 100 μm) in a long length with a Tg of approximately 75°C was used, and one side of the resin substrate was subjected to corona treatment. A PVA aqueous solution (coating solution) was prepared by dissolving 100 parts by weight of a PVA-based resin, which was prepared by mixing polyvinyl alcohol (degree of polymerization 4200, degree of saponification 99.2 mol%) and acetoacetyl-modified PVA (manufactured by Mitsubishi Chemical Corporation, trade name "Gosenex Z410") in a 9:1 ratio, with 13 parts by weight of potassium iodide. A PVA aqueous solution was applied to the corona-treated surface of a resin substrate and dried at 60°C to form a 13 μm thick PVA-based resin layer, thereby creating a laminate. The resulting laminate was uniaxially stretched 2.4 times in the longitudinal direction (longitudinal direction) in an oven at 130°C (air-assisted stretching). Next, the laminate was immersed for 30 seconds in an insolubilization bath at a liquid temperature of 40°C (a boric acid aqueous solution obtained by mixing 4 parts by weight of boric acid with 100 parts by weight of water) (insolubilization treatment). Next, the film was immersed for 60 seconds in a staining bath at 30°C (an iodine aqueous solution obtained by mixing iodine and potassium iodide in a weight ratio of 1:7 with 100 parts by weight of water) while adjusting the concentration so that the transmittance (Ts) of the final absorption polarizing film would be the desired value (staining treatment). Next, the material was immersed for 30 seconds in a crosslinking bath at a liquid temperature of 40°C (a boric acid aqueous solution obtained by mixing 3 parts by weight of potassium iodide and 5 parts by weight of boric acid with 100 parts by weight of water) (crosslinking treatment). Subsequently, the laminate was immersed in a boric acid aqueous solution (boric acid concentration 4% by weight, potassium iodide concentration 5% by weight) at a liquid temperature of 70°C, and uniaxially stretched in the longitudinal direction (longitudinal direction) between rolls with different peripheral speeds to achieve a total stretch ratio of 5.5 times (underwater stretching treatment). Subsequently, the laminate was immersed in a washing bath at a liquid temperature of 20°C (an aqueous solution obtained by mixing 4 parts by weight of potassium iodide with 100 parts by weight of water) (washing treatment). Subsequently, the laminate was dried in an oven maintained at approximately 90°C while being brought into contact with a SUS (stainless steel) heated roll whose surface temperature was maintained at approximately 75°C (drying shrinkage treatment). The shrinkage rate in the width direction of the laminate due to the drying shrinkage treatment was 5.2%. In this way, an absorption-type polarizing film with a thickness of approximately 5 μm was formed on a resin substrate. A cycloolefin resin film (thickness: 25 μm) was bonded to the surface of the obtained absorption polarizing film (the side opposite to the resin substrate) via an ultraviolet-curing adhesive. Specifically, the curing adhesive was applied to a total thickness of approximately 1 μm and bonded using a roll press. Then, UV light was irradiated from the cycloolefin resin film side to cure the adhesive. Next, the resin substrate was peeled off. This resulted in a polarizing film having a cycloolefin resin film / absorption polarizing film structure. The polarizing film had a single-unit transmittance (Ts) of 43.4%, a polarization degree of 99.993%, and parallel a * The value is -2.0, parallel b * The value was 6.1.

[0050] [Example 1] Laminate 1 was fabricated by laminating four λ / 4 components obtained in Manufacturing Example 1 onto one side of the polarizing film obtained in Manufacturing Example 2, so that they were designated as λ / 4 components 1 to 4 and had the axial relationships and lamination configuration shown in Table 1 (the angles shown in Table 1 are angles based on the absorption axis direction of the absorption polarizing film as viewed from the polarizing film side, where "+" means clockwise and "-" means counterclockwise). The lamination of each component was performed by bonding them together via an acrylic adhesive layer (manufactured by Nitto Denko Corporation, 5 μm thick).

[0051] [Comparative Example 1] Laminate C1 was fabricated in the same manner as in Example 1, except that the four λ / 4 members 1 to 4 were laminated in the axial relationship and laminated configuration shown in Table 1.

[0052] [Table 1]

[0053] Table 2 shows the measurement results of the individual transmittance and hue of the laminates obtained in the above examples and comparative examples. The laminates prepared in the examples and comparative examples are simplified evaluation models of the display system according to the embodiment of the present invention. Specifically, the hue of light incident on the λ / 4 member 1 side of the laminate and emitted from the polarizing film side can be evaluated as the hue of the light emitted forward from the display element via the polarizing member in the display system according to the embodiment of the present invention, after passing through the first phase difference member and the second phase difference member in that order, and then being reflected by the reflecting part and the half mirror, passing through the second phase difference member two more times, and then passing through the reflecting part and emitted forward.

[0054] [Table 2]

[0055] As shown in Table 2, according to the display system of the embodiment of the present invention, by arranging the first λ / 4 member and the second λ / 4 member so that their slow axes are parallel to each other, the coloration of the transmitted light is suppressed compared to a configuration in which the slow axes are orthogonal to each other, and transmitted light with a neutral hue can be obtained.

[0056] 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]

[0057] The display system according to an embodiment of the present invention can be used, for example, in a display device such as VR goggles. [Explanation of symbols]

[0058] 2 Display System 4. Lens section 12 Display elements 14 Reflector 16 First lens section 18 Half Mirror 20 First phase difference member 22 Second phase difference member 24 Second lens section

Claims

1. A display system that displays images to the user, A display element having a display surface that emits light representing an image forward via a polarizing member, Displaced in front of the display element, and including a reflective polarizing member, a reflective portion that reflects light emitted from the display element, A first lens portion is arranged in the optical path between the display element and the reflecting portion, A half-mirror is 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 reflecting portion toward the reflecting portion, A first λ / 4 member is arranged in the optical path between the display element and the half mirror, A second λ / 4 member is positioned in the optical path between the half mirror and the reflecting portion, Equipped with, The angle between the slow axis of the first λ / 4 member and the slow axis of the second λ / 4 member is within the range of 0° ± 5°. The angle between the polarization direction of the light emitted through the polarizing member and the reflection axis of the reflective polarizing member is within the range of 90° ± 5°. The angle between the absorption axis of the polarizing member included in the display element and the lagging axis of the first λ / 4 member is 40° to 50°. The angle between the absorption axis of the polarizing member included in the display element and the lagging axis of the second λ / 4 member is 40° to 50°. The first λ / 4 member and the second λ / 4 member are, 1.03 < Re(650) / Re(550) < 1.20, and 1.05<Re(750) / Re(550)<1.36, A display system that satisfies the requirements.

2. The display system according to claim 1, wherein the first lens portion and the half mirror are integrated.

3. The display system according to claim 1, further comprising a second lens portion positioned in front of the reflective portion.

4. The display system according to claim 1, wherein the reflective portion includes an absorbing polarizing member disposed in front of the reflective polarizing member.

5. The display system according to claim 4, wherein the angle between the reflection axis of the reflective polarizing member and the absorption axis of the absorptive polarizing member is within the range of 0° ± 5°.

6. The steps include passing light representing an image emitted through a polarizing member through a first λ / 4 member, The steps include: passing the light that has passed through the first λ / 4 member through the half mirror and the first lens section; The steps include: passing the light that has passed through the half mirror and the first lens portion through the second λ / 4 member; The steps include: reflecting the light that has passed through the second λ / 4 member toward the half mirror using a reflective section that includes a reflective polarizing member; The step of making the light reflected by the reflecting portion and the half-mirror passable through the reflecting portion by the second λ / 4 member, The angle between the slow axis of the first λ / 4 member and the slow axis of the second λ / 4 member is within the range of 0° ± 5°. The angle between the polarization direction of the light emitted through the polarizing member and the reflection axis of the reflective polarizing member is within the range of 90° ± 5°. The angle between the absorption axis of the polarization member and the slow axis of the first λ / 4 member is 40° to 50°. The angle between the absorption axis of the polarization member and the slow axis of the second λ / 4 member is 40° to 50°. The first λ / 4 member and the second λ / 4 member are, 1.03 < Re(650) / Re(550) < 1.20, and 1.05<Re(750) / Re(550)<1.36, A display method that satisfies the requirements.

7. A display body comprising the display system described in any one of claims 1 to 5.

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