Display system and method for manufacturing display system

Abstract

Provided is a method of manufacturing a display system that is for displaying an image to a user and that comprises: a display element having a display surface that, via a polarization member, emits light representing an image in the forward direction; a reflection-type polarization member that is disposed in front of the display element and reflects the light emitted from the display element; a first lens part that is disposed on an optical path between the display element and the reflection-type polarization member; a half mirror that is disposed between the display element and the first lens part, and that transmits the light emitted from the display element and reflects the light reflected by the reflection-type polarization member toward the reflection-type polarization member; a first retardation member that is disposed on an optical path between the display element and the half mirror, and that includes a first λ / 4 member and a first λ / 2 member; and a second retardation member that is disposed on an optical path between the half mirror and the reflection-type polarization member, and that includes a second λ / 4 member and a second λ / 2 member. As the first retardation member and the second retardation member, used is a retardation member including a λ / 4 member and a λ / 2 member which both have an in-plane retardation equal to or greater than or equal to or less than a reference in-plane retardation.

Description

Display system and method for manufacturing a display system

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

[0002] Image display devices typified by liquid crystal display devices and electroluminescent (EL) display devices (e.g., 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 (see, for example, Patent Document 1).

[0003] In recent years, new applications for image display devices have been developed. For example, near-eye displays (VR goggles) for realizing Virtual Reality (VR) have begun to be commercialized. Since VR goggles are being considered for use in various scenarios, higher definition and the like are desired.

[0004] Japanese Patent Application Laid-Open No. 2021-103286

[0005] In view of the above, the main object of the present invention is to provide a display system such as a high-definition VR goggles and a method for manufacturing the same.

[0006] [1] According to one aspect of the present invention, a display element having a display surface that emits light representing an image forward via a polarizing member; a reflective polarizing member disposed in front of the display element and reflecting the light emitted from the display element; a first lens portion disposed in 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 the light emitted from the display element and reflects the light reflected by the reflective polarizing member toward the reflective polarizing member; and between the display element and the half mirror A method for manufacturing a display system that displays an image to a user, comprising: a first phase difference member arranged on the optical path and including a first λ / 4 member and a first λ / 2 member; and a second phase difference member arranged on the optical path between the half mirror and the reflective polarizing member and including a second λ / 4 member and a second λ / 2 member, wherein the in-plane phase difference of the first λ / 4 member and the second λ / 4 member is Q nm, and the in-plane phase difference of the first λ / 2 member and the second λ / 2 member is H nm, and the difference from Q nm is within a predetermined range. The process involves preparing multiple λ / 4 members, preparing multiple λ / 2 members having an in-plane phase difference within a predetermined range from Hnm, dividing the λ / 4 members into group A1 having an in-plane phase difference of Qnm or greater than or greater than Qnm and group A2 having an in-plane phase difference of Qnm or less than or less than Qnm, dividing the λ / 2 members into group B1 having an in-plane phase difference of Hnm or greater than or greater than Hnm and group B2 having an in-plane phase difference of Hnm or less than or less than Hnm, and using one of the following methods (i) to (iv) to prepare the first phase difference member and the second phase difference (i) to manufacture the first phase difference member using a λ / 4 member selected from group A1 and a λ / 2 member selected from group B1, and to manufacture the second phase difference member using a λ / 4 member selected from group A1 and a λ / 2 member selected from group B1, (ii) to manufacture the first phase difference member using a λ / 4 member selected from group A2 and a λ / 2 member selected from group B2, and to manufacture the second phase difference member using a λ / 4 member selected from group A2 and a λ / 2 member selected from group B2.A manufacturing method is provided which includes (iii) manufacturing the first phase difference member using a λ / 4 member selected from group A1 and a λ / 2 member selected from group B1, and manufacturing the second phase difference member using a λ / 4 member selected from group A2 and a λ / 2 member selected from group B2, and (iv) manufacturing the first phase difference member using a λ / 4 member selected from group A2 and a λ / 2 member selected from group B2, and manufacturing the second phase difference member using a λ / 4 member selected from group A1 and a λ / 2 member selected from group B1. [2] The manufacturing method described in [1] above is to prepare a plurality of λ / 4 members having Re(550) in the range of Qs ± 3.5 nm, wherein the in-plane phase difference Re(550) of the first λ / 4 member and the second λ / 4 member is Qs nm, and the in-plane phase difference Re(550) of the first λ / 2 member and the second λ / 2 member is Hs nm, and to prepare a plurality of λ / 4 members having Re(550) in the range of Hs ± 3.2 nm, and to prepare a plurality of λ / 2 members having Re(550) in the range of Hs ± 3.2 nm, and to Qs nm This may include dividing the materials into groups A1 having Re(550) of Qs nm or more or greater than Qs nm and group A2 having Re(550) of Qs nm or less or less than Qs nm, dividing the λ / 2 members into groups B1 having Re(550) of Hs nm or more or greater than Hs nm and group B2 having Re(550) of Hs nm or less or less than Hs nm, and manufacturing the first phase difference member and the second phase difference member by any of the methods (i) to (iv) above. [3] In the manufacturing method described in [2] above, preparing a plurality of λ / 4 members having Re(550) in the range of Qs ± 3.5 nm may include preparing a plurality of λ / 4 members having Re(550) in the range of Qs × 0.975 to Qs × 1.025. [4] In the manufacturing method described in [2] or [3] above, preparing a plurality of λ / 2 members having Re(550) in the range of Hs ± 3.2 nm may include preparing a plurality of λ / 2 members having Re(550) in the range of Hs × 0.99 to Hs × 1.01. [5] In the manufacturing method described in any of [1] to [4] above, the Nz coefficients of the first λ / 4 member, the second λ / 4 member, the first λ / 2 member, and the second λ / 2 member are,[6] In the manufacturing method described in any of [1] to [5] above, the Re(450) / Re(550) of the first λ / 4 member, the second λ / 4 member, the first λ / 2 member, and the second λ / 2 member may each be 1.05 or less. [7] In the manufacturing method described in any of [1] to [6] above, the angle between the slow axis of the first λ / 4 member and the slow axis of the first λ / 2 member may be within the range of 60°±5°. [8] In the manufacturing method described in any of [1] to [7] above, the angle between the slow axis of the second λ / 4 member and the slow axis of the second λ / 2 member may be within the range of 60°±5°. [9] In the manufacturing method described in any of [1] to [8] above, the angle between the slow axis of the first λ / 4 member and the slow axis of the second λ / 4 member may be 0° to 5°.

[10] In the manufacturing method described in any of [1] to [9] above, the angle between the slow axis of the first λ / 2 member and the slow axis of the second λ / 2 member may be 0° to 5°.

[11] According to another aspect of the present invention, a display system for displaying an image to a user, comprising: a display element having a display surface that emits light representing an image forward via a polarizing member; a reflective polarizing member disposed in front of the display element and reflecting the light emitted from the display element; 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 the light emitted from the display element and reflects the light reflected by the reflective polarizing member toward the reflective polarizing member; and the display element and the half A display system is provided which includes a first phase difference member, which is arranged in the optical path between the half mirror and the reflective polarizing member and includes a first λ / 4 member and a first λ / 2 member, and a second phase difference member, which is arranged in the optical path between the half mirror and the reflective polarizing member and includes a second λ / 4 member and a second λ / 2 member, wherein when the Re(550) of the first λ / 4 member, the first λ / 2 member, the second λ / 4 member and the second λ / 2 member are Q1 nm, H1 nm, Q2 nm and H2 nm, respectively, the relationship 0 ≤ |Q1 - Q2| ≤ 7 and the relationship 0 ≤ |H1 - H2| ≤ 6.4 are provided.

[12] The display system described in

[11] above is3. The relationships 2 ≤ |Q1 - Q2| ≤ 7 and 0 ≤ |H1 - H2| ≤ 6.4 may be satisfied.

[0007] According to embodiments of the present invention, a display system such as high-definition VR goggles and a method for manufacturing the same are provided.

[0008] This is a schematic diagram showing the general configuration of an example of a display system according to an embodiment of the present invention. This is a schematic diagram illustrating direct ghosting and double bounce. This is a diagram showing the results of direct ghosting evaluation and double bounce evaluation. This is a diagram showing the results of direct ghosting evaluation and double bounce evaluation. This is a diagram showing the results of direct ghosting evaluation and double bounce evaluation.

[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 for clarity, they are merely examples and do not limit the interpretation of the present invention.

[0010] (Definitions of Terms and Symbols) The definitions of terms and symbols used herein are as follows: (1) Refractive Index (nx, ny, nz) "nx" is the refractive index in the direction in which the refractive index in the plane is maximum (i.e., in the direction of the slow phase axis), "ny" is the refractive index in the direction perpendicular to the slow phase axis in the plane (i.e., in the direction of the fast phase axis), 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 by 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 a wavelength of 550 nm at 23°C. Rth(λ) is obtained by the formula: Rth(λ) = (nx - nz) × d, where d (nm) is the thickness of the layer (film). (4) Nz coefficient The Nz coefficient is obtained by Nz = Rth / Re. (5) Angle When an angle is referred to in this specification, unless otherwise specified, the angle includes both clockwise (+) and counterclockwise (-) with respect to the reference direction. Therefore, for example, "45°" means ±45°. Also in this specification, "approximately parallel" includes the range of 0° ± 10°, preferably within the range of 0° ± 5°. "Approximately orthogonal" includes the range of 90° ± 10°, preferably within the range of 90° ± 5°.

[0011] A. Display System Figure 1 is a schematic diagram showing the general configuration of an example of a display system according to an 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 14a, 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.

[0012] 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 first linearly polarized light.

[0013] The first phase difference member 20 includes a first λ / 2 member 20H and a first λ / 4 member 20Q arranged in this order toward the front. The first phase difference member 20 can convert a first linearly polarized light incident on the first phase difference member 20 into a first circularly polarized light. The first phase difference member 20 may be provided integrally with the display element 12.

[0014] 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.

[0015] The second phase difference member 22 includes a second λ / 4 member 22Q and a second λ / 2 member 22H arranged in this order toward the front. The second phase difference member 22 is configured to transmit light reflected by the reflecting portion 14 and the half mirror 18 through the reflecting portion 14. The second phase difference member 22 may be provided integrally with the first lens portion 16.

[0016] The first circularly polarized light emitted from the first phase difference member 20 passes through the half mirror 18 and the first lens portion 16 and is converted into a second linearly polarized light by the second phase difference member 22. The second linearly polarized light emitted from the second phase difference member 22 is reflected towards the half mirror 18 without passing through the reflective polarizing member included in the reflecting portion 14. At this time, the polarization direction of the second linearly polarized light incident on the reflective polarizing member included in the reflecting portion 14 is in the same direction as the reflection axis of the reflective polarizing member. Therefore, the second linearly polarized light incident on the reflecting portion is reflected by the reflective polarizing member.

[0017] The second linearly polarized light reflected by the reflective section 14 is converted into a second circularly polarized light by the second phase difference member 22, and the second circularly polarized light emitted from the second phase difference member 22 passes through the first lens section 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 section 16 and is converted into a third linearly polarized light by the second phase difference member 22. The third linearly polarized light is transmitted through the reflective polarizing member. At this time, the polarization direction of the third linearly polarized light incident on the reflective polarizing member included in the reflective section 14 is in the same direction as the transmission axis of the reflective polarizing member. Therefore, the third linearly polarized light incident on the reflective section 14 is transmitted through the reflective polarizing member.

[0018] Light that passes through the reflective section 14 passes through the second lens section 24 and enters the user's eye 26.

[0019] The display system 2 may include an absorptive polarizing member (typically an absorptive polarizing film) in front of the reflective polarizing member in the reflective section 14. The reflection axis of the reflective polarizing member and the absorption axis of the absorptive polarizing member may be arranged substantially parallel to each other, and the transmission axis of the reflective polarizing member and the transmission axis of the absorptive polarizing member may be arranged substantially parallel to each other. As a result, the third linearly polarized light that has passed through the reflective polarizing member can pass through the absorptive polarizing member as is.

[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 included in the reflection section 14 may be arranged substantially parallel to each other or substantially 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 λ / 2 member 20H is, for example, 5° to 35°, may be 10° to 20°, may be 12° to 18°, or may be about 15°. The angle between the absorption axis of the above polarizing member and the slow axis of the first λ / 4 member 20Q is, for example, 55° to 85°, may be 70° to 80°, may be 72° to 78°, or may be about 75°. The angle between the slow axis of the first λ / 2 member 20H and the slow axis of the first λ / 4 member 20Q is, for example, 55° to 65°, may be 57° to 63°, may be 58° to 62°, or may be about 60°. The angle between the absorption axis of the polarizing member included in the display element 12 and the slow axis of the second λ / 2 member 22H is, for example, 5° to 35°, may be 10° to 20°, may be 12° to 18°, or may be about 15°. The angle between the absorption axis of the above polarizing member and the slow axis of the second λ / 4 member 22Q is, for example, 55° to 85°, may be 70° to 80°, may be 72° to 78°, or may be about 75°. The angle between the slow axis of the second λ / 2 member 22H and the slow axis of the second λ / 4 member 22Q is, for example, 55° to 65°, may be 57° to 63°, may be 58° to 62°, or may be about 60°. The angle between the slow axis of the first λ / 4 member 20Q and the slow axis of the second λ / 4 member 22Q is, for example, 0° to 5°, may be 0° to 3°, may be 0° to 2°, or may be about 0°. In this case, the angle between the slow axis of the first λ / 2 member 20H and the slow axis of the second λ / 2 member 22H is, for example, 0° to 5°, may be 0° to 3°, may be 0° to 2°, or may be about 0°.

[0021] The in-plane phase difference Re(550) of the first λ / 4 member 20Q and the second λ / 4 member 22Q 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.

[0022] The first λ / 4 member 20Q and the second λ / 4 member 22Q may each exhibit inverse dispersion wavelength characteristics, positive dispersion wavelength characteristics, or flat wavelength dispersion characteristics. The Re(450) / Re(550) of the first λ / 4 member and the second λ / 4 member are, for example, 1.05 or less. When the first λ / 4 member and the second λ / 4 member exhibit inverse dispersion wavelength characteristics, Re(450) / Re(550) may be, for example, 0.75 or more and less than 1, and 0.8 or more and 0.95 or less. When the first λ / 4 member and the second λ / 4 member exhibit flat wavelength dispersion characteristics, Re(450) / Re(550) may be, for example, 0.99 to 1.03, and Re(650) / Re(550) may be, for example, 0.98 to 1.02.

[0023] The first λ / 4 member 20Q and the second λ / 4 member 22Q are, preferably, so-called Z plates whose refractive index characteristics exhibit the relationship nx > nz > ny. The Nz coefficients of the first λ / 4 member and the second λ / 4 member are, for example, 0.2 to 0.8, preferably 0.3 to 0.7, more preferably 0.4 to 0.6, and even more preferably 0.46 to 0.54.

[0024] The in-plane phase difference Re(550) of the first λ / 2 member 20H and the second λ / 2 member 22H is, for example, 200 nm to 330 nm, but may also be 230 nm to 330 nm, 230 nm to 290 nm, or 250 nm to 280 nm.

[0025] The first λ / 2 member 20H and the second λ / 2 member 22H may each exhibit inverse dispersion wavelength characteristics, positive dispersion wavelength characteristics, or flat wavelength dispersion characteristics. The Re(450) / Re(550) of the first λ / 2 member and the second λ / 2 member are, for example, 1.05 or less. When the first λ / 2 member and the second λ / 2 member exhibit inverse dispersion wavelength characteristics, Re(450) / Re(550) may be, for example, 0.75 or more and less than 1, and 0.8 or more and 0.95 or less. When the first λ / 2 member and the second λ / 2 member exhibit flat wavelength dispersion characteristics, Re(450) / Re(550) may be, for example, 0.99 to 1.03, and Re(650) / Re(550) may be, for example, 0.98 to 1.02.

[0026] The first λ / 2 member 20H and the second λ / 2 member 22H are, preferably, so-called Z plates whose refractive index characteristics exhibit the relationship nx > nz > ny. The Nz coefficients of the first λ / 2 member and the second λ / 2 member are, for example, 0.2 to 0.8, preferably 0.3 to 0.7, more preferably 0.4 to 0.6, and even more preferably 0.46 to 0.54.

[0027] As described above, in the display system 2, linearly polarized light emitted forward from the display surface 12a of the display element 12 passes through the first phase difference member 20 and the second phase difference member 22 in that order, then passes through the second phase difference member 22 two more times due to reflection by the reflective polarizing member 14a and re-reflection by the half mirror 18, and then passes through the reflective polarizing member 14a and is emitted forward, thereby being visible to the viewer. In such an optical path, it is desirable that the first λ / 4 member 20Q in the first phase difference member 20 and the second λ / 4 member 22Q in the second phase difference member 22 have a predetermined in-plane phase difference that coincides with each other (preferably a reference in-plane phase difference as a design reference value in the display system (hereinafter also referred to as "reference Re")), and it is also desirable that the first λ / 2 member 20H in the first phase difference member 20 and the second λ / 2 member 22H in the second phase difference member 22 have a predetermined in-plane phase difference that coincides with each other (preferably a reference in-plane phase difference as a design reference value in the display system). If the in-plane phase difference with respect to the reference Re becomes large, the light emitted from the display element 12 will deviate from the designed optical path, and problems such as direct ghosting (DG), where light that should be reflected by the reflective polarizing member 14a is transmitted through the reflective polarizing member 14a and becomes visible, and double bounce (DB), where light that should pass through the reflective polarizing member 14a is reflected by the reflective polarizing member 14a before becoming visible, may occur, as shown in Figure 2.

[0028] When the reference Re(550) of the first λ / 4 member and the second λ / 4 member in the display system 2 is Qsnm, the measured Re(550) of the first λ / 4 member and the second λ / 4 member are Q1nm and Q2nm, respectively, the reference Re(550) of the first λ / 2 member and the second λ / 2 member is Hsnm, and the measured Re(550) of the first λ / 2 member and the second λ / 2 member are H1nm and H2nm, respectively, it is preferable that Qs, Q1, Q2, Hs, H1, and H2 satisfy any of the following (a) to (d). (a) Q1 ≥ Qs and H1 ≥ Hs, and Q2 ≥ Qs and H2 ≥ Hs (b) Q1 ≤ Qs and H1 ≤ Hs, and Q2 ≤ Qs and H2 ≤ Hs (c) Q1 ≥ Qs and H1 ≥ Hs, and Q2 ≤ Qs and H2 ≤ Hs (d) Q1 ≤ Qs and H1 ≤ Hs, and Q2 ≥ Qs and H2 ≥ Hs

[0029] The above (a) to (d) means that the combination of the first λ / 4 member and the first λ / 2 member constituting the first phase difference member, and the combination of the second λ / 4 member and the second λ / 2 member constituting the second phase difference member, will be either a combination of upper deviations or a combination of lower deviations (where "upper deviation" means having an Re(550) of 550 or higher than the reference Re(550), and "lower deviation" means having an Re(550) of 550 or lower than the reference Re(550)). Direct ghosting and / or double bounce can be suppressed by using a combination of a first phase difference member including a first λ / 4 member and a first λ / 2 member, both having a Re(550) of or greater than the reference Re(550), or a first phase difference member including a first λ / 4 member and a first λ / 2 member, both having a Re(550) of or less than the reference Re(550), and a second phase difference member including a second λ / 4 member and a second λ / 2 member, both having a Re(550) of or greater than the reference Re(550), or a second phase difference member including a second λ / 4 member and a second λ / 2 member, both having a Re(550) of or less than the reference Re(550).

[0030] Q1, Q2, and Qs satisfy, for example, the relationships -3.5 ≤ Qs - Q1 ≤ 3.5 and -3.5 ≤ Qs - Q2 ≤ 3.5, preferably -3 ≤ Qs - Q1 ≤ 3 and -3 ≤ Qs - Q2 ≤ 3, and more preferably -2.5 ≤ Qs - Q1 ≤ 2.5 and -2.5 ≤ Qs - Q2 ≤ 2.5. The effects of the present invention can be suitably obtained when the deviation of Q1 and Q2 with respect to Qs is, for example, within the range of ±3.5 nm.

[0031] In one embodiment, Q1 and Q2 are, for example, within the range of Qs × 0.975 to Qs × 1.025, preferably Qs × 0.98 to Qs × 1.02, more preferably Qs × 0.985 to Qs × 1.015, and even more preferably Qs × 0.99 to Qs × 1.01. The effects of the present invention can be suitably obtained when the deviation of Q1 and Q2 from Qs is ±2.5% or less of Qs, preferably ±2% or less.

[0032] H1, H2, and Hs satisfy, for example, the relationships -3.2 ≤ Hs - H1 ≤ 3.2 and -3.2 ≤ Hs - H2 ≤ 3.2, preferably -3 ≤ Hs - H1 ≤ 3 and -3 ≤ Hs - H2 ≤ 3, and more preferably -2 ≤ Hs - H1 ≤ 2 and -2 ≤ Hs - H2 ≤ 2. The effects of the present invention can be favorably obtained when the deviation of H1 and H2 from Hs is, for example, within the range of ±3.2 nm, preferably within the range of ±3 nm.

[0033] In one embodiment, H1 and H2 are preferably in the range of Hs × 0.99 to Hs × 1.01, and more preferably in the range of Hs × 0.995 to Hs × 1.005. The effects of the present invention can be suitably obtained when the deviation of H1 and H2 from Hs is 1% or less of Hs.

[0034] Qs 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. Hs is, for example, 200 nm to 330 nm, but may also be 230 nm to 330 nm, 230 nm to 290 nm, or 250 nm to 280 nm.

[0035] In one embodiment, Q1, Q2, H1, and H2 satisfy the relationships 0 ≤ |Q1 - Q2| ≤ 7 and 0 ≤ |H1 - H2| ≤ 6.4. Even if one or more in-plane phase differences of the first λ / 4 member, the second λ / 4 member, the first λ / 2 member, and the second λ / 2 member deviate from their reference in-plane phase difference, satisfying the above relationships allows for favorable suppression of direct ghosting and / or double bounce.

[0036] |Q1-Q2| is, for example, 7 or less, and can be 6 or less, or 5 or less. |Q1-Q2| is, for example, 0 or more, and can be 2 or more, 3 or more, 3.2 or more, greater than 3.2, or greater than 3.5. Even if Q1 and Q2 do not match, if the difference between them is within the above range, direct ghosting and / or double bounce can be suitably suppressed.

[0037] |H1-H2| is, for example, 6.4 or less, and can be 6 or less, 5 or less, or 4 or less. |H1-H2| is, for example, 0 or more, and can be 2 or more, 3 or more, 3.2 or more, greater than 3.2, or greater than 3.5. Even if H1 and H2 do not match, if the difference between them is within the above range, direct ghosting and / or double bounce can be suitably suppressed.

[0038] The first λ / 4 member and the second λ / 4 member (sometimes collectively referred to as the λ / 4 member), and the first λ / 2 member and the second λ / 2 member (sometimes collectively referred to as the λ / 2 member), are each formed from any suitable material that can satisfy the above characteristics. The λ / 4 member and the λ / 2 member may each be, for example, a stretched film of a resin film or an oriented solidified layer of a liquid crystal compound.

[0039] Examples of resins included in the above-mentioned resin film include polyarylate resins, polyamide resins, polyimide resins, polyester resins, polyaryletherketone resins, polyamideimide resins, polyesterimide resins, polyvinyl alcohol resins, polyfumarate ester resins, polyethersulfone resins, polysulfone resins, cycloolefin resins, polycarbonate resins, cellulose resins, and polyurethane resins. These resins may be used individually or in combination (e.g., blended, copolymerized). Among these, cycloolefin resins are preferred, and norbornene resins are more preferred. Specifically, norbornene resins include the "cycloolefin resin obtained by hydrogenating a ring-opening polymer of norbornene monomers" described in Japanese Patent Application Publication No. 2006-208925.

[0040] The λ / 4 and λ / 2 members can be manufactured, for example, by laminating a high-shrinkage film (e.g., a polypropylene film) to both sides of a polymer film mainly composed of the resin described above, and then heat-stretching it using a roll stretching machine in a longitudinal uniaxial stretching method. The high-shrinkage film is used to impart a shrinkage force in a direction perpendicular to the stretching direction during heat stretching, thereby increasing the refractive index (nz) in the thickness direction of the Z plate. There are no particular restrictions on the method of laminating the high-shrinkage film to both sides of the polymer film, but one method is to provide an acrylic adhesive layer with an acrylic polymer as the base polymer between the polymer film and the high-shrinkage film for bonding.

[0041] The thickness of the λ / 4 member and the λ / 2 member is, for example, 20 μm to 200 μm, and for example, 30 μm to 150 μm.

[0042] The reflective polarizing member 14a can transmit polarized light parallel to its transmission axis (typically linearly polarized light) while maintaining its polarization state, and reflect light with other polarization states (typically light with a polarization state orthogonal to its transmission axis). Typically, the reflective polarizing member is composed of a film having a multilayer structure (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. Examples of commercially available reflective polarizing films include the product names "DBEF" and "APF" manufactured by 3M, and the product name "APCF" manufactured by Nitto Denko Corporation.

[0043] The orthogonal transmittance (Tc) of the reflective polarizing member (reflective polarizing film) can be, for example, 0.001% to 3%. The single transmittance (Ts) of the reflective polarizing member (reflective polarizing film) is, for example, 43% to 49%, preferably 45% to 47%. The degree of polarization (P) of the reflective polarizing member (reflective polarizing film) can be, for example, 92% to 99.99%.

[0044] The polarizing member that may be included in the display element 12 and the absorption-type polarizing member that may be included in the reflection unit 14 may typically include a resin film containing a dichroic substance as an absorption-type polarizing film. The orthogonal transmittance (Tc) of the polarizing member or the absorption-type polarizing member is preferably 0.5% or less, more preferably 0.1% or less, and even more preferably 0.05% or less. The single transmittance (Ts) of the polarizing member or the absorption-type polarizing member is, for example, 41.0% to 45.0%, preferably 42.0% or more. The degree of polarization (P) of the polarizing member or the absorption-type polarizing member is, for example, 99.0% to 99.997%, preferably 99.9% or more.

[0045] Although not shown, a third retardation member may be disposed between the display element 12 and the first retardation member 20. The third retardation member is provided, for example, from the viewpoint of compensating for the deviation of the optical axis relationship between the polarizing member included in the display element and the reflection-type polarizing member accompanying the change in the viewing angle. In this case, the third retardation member may include at least one optical compensation layer having a slow axis. The optical compensation layer having a slow axis may be arranged such that its slow axis is substantially orthogonal or substantially parallel to the absorption axis of the polarizing member. According to such a configuration, the light emitted as the first linearly polarized light from the display element 12 can pass through the third retardation member without substantially changing its polarization state. In this specification, the "optical compensation layer having a slow axis" means an optical compensation layer having Re(550) of 10 nm or more.

[0046] In one embodiment, the third retardation member may be composed of a member (so-called Z-plate) showing a refractive index characteristic of nx > nz > ny. In this case, the slow axis of the Z-plate may be arranged so as to be substantially orthogonal or substantially parallel to the absorption axis of the polarizing member.

[0047] The in-plane retardation Re(550) of the Z-plate is, for example, 200 nm to 350 nm, preferably 230 nm to 320 nm, more preferably 250 nm to 300 nm. The Nz coefficient of the Z-plate is, for example, 0.2 to 0.8, preferably 0.3 to 0.7, more preferably 0.4 to 0.6. The Z-plate may exhibit inverse dispersion wavelength characteristics, positive dispersion wavelength characteristics, or flat wavelength dispersion characteristics.

[0048] In another embodiment, the third retardation member includes a layer (so-called negative B-plate) showing a refractive index characteristic of nx > ny > nz and a layer (so-called positive B-plate) showing a refractive index characteristic of nz > nx > ny, which are laminated in this order toward the first retardation member side. The slow axes of both the negative B-plate and the positive B-plate may be arranged so as to be substantially orthogonal to the absorption axis of the polarizing member.

[0049] The in-plane phase difference Re(550) of the negative B plate described above is, for example, 60 nm to 190 nm, preferably 80 nm to 170 nm, and more preferably 100 nm to 150 nm. The phase difference Rth(550) in the thickness direction of the negative B plate is, for example, 60 nm to 200 nm, preferably 80 nm to 180 nm, and more preferably 100 nm to 160 nm. The Nz coefficient of the negative B plate is, for example, 1.1 to 3.0, and preferably 1.1 to 2.7. The negative B plate may exhibit inverse dispersion wavelength characteristics, positive dispersion wavelength characteristics, or flat wavelength dispersion characteristics.

[0050] The in-plane phase difference Re(550) of the positive B plate described above is, for example, 10 nm to 60 nm, preferably 15 nm to 55 nm, and more preferably 20 nm to 45 nm. The phase difference Rth(550) in the thickness direction of the positive B plate is, for example, -250 nm to -10 nm, preferably -200 nm to -20 nm, and more preferably -150 nm to -60 nm. The Nz coefficient of the positive B plate is, for example, -4.0 to -1.0, preferably -3.5 to -1.5, and more preferably -3.0 to -2.0. The positive B plate may exhibit inverse dispersion wavelength characteristics, positive dispersion wavelength characteristics, or flat wavelength dispersion characteristics.

[0051] The forming material and manufacturing method for the Z-plate described above may be as described above with respect to the λ / 4 member and the λ / 2 member. The negative B-plate and the positive B-plate can each be manufactured by a manufacturing method known in the art using any suitable resin material that satisfies the above characteristics.

[0052] The thickness of the third phase difference member varies depending on its configuration, but is, for example, 200 μm or less, preferably 5 μm to 170 μm, and more preferably 10 μm to 150 μm.

[0053] B. Method of manufacturing the display system The display system described in Section A may be manufactured by any suitable method. For example, in the case where the reference in-plane phase difference of the first λ / 4 member and the second λ / 4 member is set to Q nm, and the reference in-plane phase difference of the first λ / 2 member and the second λ / 2 member is set to H nm, the process is as follows: Prepare a plurality of λ / 4 members having an in-plane phase difference within a predetermined range from Q nm (Step I); Prepare a plurality of λ / 2 members having an in-plane phase difference within a predetermined range from H nm (Step II); Group the λ / 4 members into group A1 having an in-plane phase difference of Q nm or more or greater than Q nm and group A2 having an in-plane phase difference of Q nm or less or less than Q nm (Step III); Group the λ / 2 members into group B1 having an in-plane phase difference of H nm or more or greater than H nm and group B2 having an in-plane phase difference of H nm or less or less than H nm (Step IV); and manufacture the first phase difference member and the second phase difference member by any of the following methods (i) to (iv) (Step V). (i) The first phase difference member is manufactured using a λ / 4 member selected from group A1 and a λ / 2 member selected from group B1, and the second phase difference member is manufactured using a λ / 4 member selected from group A1 and a λ / 2 member selected from group B1, (ii) The first phase difference member is manufactured using a λ / 4 member selected from group A2 and a λ / 2 member selected from group B2, and the second phase difference member is manufactured using a λ / 4 member selected from group A2 and a λ / 2 member selected from group B2, (iii) The first phase difference member is manufactured using a λ / 4 member selected from group A1 and a λ / 2 member selected from group B1, and the second phase difference member is manufactured using a λ / 4 member selected from group A2 and a λ / 2 member selected from group B2, (iv) The first phase difference member is manufactured using a λ / 4 member selected from group A2 and a λ / 2 member selected from group B2, and the second phase difference member is manufactured using a λ / 4 member selected from group A1 and a λ / 2 member selected from group B1.

[0054] A manufacturing method according to one embodiment of the present invention is as follows: The reference Re(550) of the first λ / 4 member and the second λ / 4 member is set to Qsnm, and the reference Re(550) of the first λ / 2 member and the second λ / 2 member is set to Hsnm; a plurality of λ / 4 members having Re(550) in the range of Qs ± 3.5nm is prepared (Step I); a plurality of λ / 2 members having Re(550) in the range of Hs ± 3.2nm is prepared (Step II); the λ / 4 members are divided into group A1 having Re(550) of Qsnm or greater or greater than Qsnm and group A2 having Re(550) of Qsnm or less or less than Qsnm (Step III); The process may include: dividing the above λ / 2 members into group B1 having Re(550) of Hsnm or greater or greater than Hsnm and group B2 having Re(550) of Hsnm or less or less than Hsnm (step IV); and manufacturing the first phase difference member and the second phase difference member by any of the above methods (i) to (iv) (step V). The above embodiments will be described in detail below, with the above embodiments as representative examples. However, the manufacturing method of the display system of the present invention is not limited to the above representative examples. For example, the in-plane phase difference may be the in-plane phase difference at a wavelength X nm other than 550 nm. In that case, the difference between the in-plane phase difference (Q nm) of Re(X) of the λ / 4 member prepared in step I and the in-plane phase difference (H nm) of Re(X) of the λ / 2 member prepared in step II can be appropriately adjusted by referring to the above representative examples. Specifically, the difference in in-plane phase difference at the above wavelength X nm can be adjusted such that Q1, Q2, H1, and H2 satisfy the relationships 0 ≤ |Q1 - Q2| ≤ 7 and 0 ≤ |H1 - H2| ≤ 6.4.

[0055] [Step I] In Step I, a plurality of λ / 4 members having Re(550) in the range of Qs ± 3.5 nm, for example, in the range of Qs ± 3.2 nm or Qs ± 3 nm, are prepared. The λ / 4 members may be elongated or sheet-like. In this specification, "elongated" means an elongated shape in which the length is sufficiently longer than the width, and for example, includes an elongated shape in which the length is 10 times or more, preferably 20 times or more, than the width. Sheet-like λ / 4 members may be, for example, substantially rectangular in shape.

[0056] For example, a long λ / 4 member having Re(550) within the range of Qs ± 3.5 nm can be obtained by preparing a wide and long λ / 4 member (mother λ / 4 member), slitting the mother λ / 4 member along its longitudinal direction and, if necessary, along its width direction to obtain a plurality of slit λ / 4 members, obtaining the Re(550) of the slit λ / 4 members, and selecting a slit λ / 4 member having Re(550) within the range of Qs ± 3.5 nm.

[0057] For example, a single-wafer λ / 4 member having Re(550) within the range of Qs ± 3.5 nm can be obtained by preparing a mother λ / 4 member, slitting the mother λ / 4 member along the longitudinal direction and, if necessary, along the width direction to obtain multiple slit λ / 4 members, punching out the slit λ / 4 members so that the angle between each side and the slow axis is a predetermined angle to obtain multiple single-wafer λ / 4 members, obtaining Re(550) for the single-wafer λ / 4 members, and selecting a single-wafer λ / 4 member having Re(550) within the range of Qs ± 3.5 nm.

[0058] Preparing the mother λ / 4 member may include selecting a wide and long λ / 4 member in which the variation of Re(550) in the width direction is, for example, 10 nm or less, preferably 7 nm or less. The width of the mother λ / 4 member may be, for example, 500 mm to 1500 mm, or for example, 900 mm to 1200 mm. The length of the mother λ / 4 member may be, for example, 100 m to 2000 m, or for example, 500 m to 1000 m.

[0059] The Re(550) of an elongated λ / 4 member can be obtained, for example, by measuring the Re(550) at multiple locations in the width direction at the starting end of the elongated λ / 4 member (for example, two locations at both ends in the width direction) and / or at multiple locations in the width direction at the ending end (for example, two locations at both ends in the width direction), and calculating the average value.

[0060] The Re(550) of a single-leaf λ / 4 member can be obtained, for example, by measuring the Re(550) at multiple locations (e.g., two or more or all corners) within the plane of the single-leaf λ / 4 member and calculating their average value. Alternatively, for example, several λ / 4 members may be selected from a plurality of single-leaf λ / 4 members (for example, 2 to 6 λ / 4 members may be selected from 30 to 300 single-leaf λ / 4 members), and the Re(550) may be measured and calculated for each of the selected λ / 4 members in the same manner as above. The average value of the calculated Re(550) for each λ / 4 member may then be applied as the Re(550) of the plurality of single-leaf λ / 4 members. For example, from a plurality of sheet-like λ / 4 members punched out from a single slit λ / 4 member, two λ / 4 members may be selected: one punched out early (e.g., at the starting end) and one punched out later (e.g., at the ending end). Re(550) may be measured and calculated for each λ / 4 member in the same manner as described above, and the average value may be applied as the Re(550) for all sheet-like λ / 4 members punched out from the same slit λ / 4 member.

[0061] [Step II] In Step II, a plurality of λ / 2 members having Re(550) within the range of Hs ± 3.2 nm, for example, within the range of Hs ± 3 nm, are prepared. The λ / 2 members may be elongated or in the form of single leaves. Single-leaf λ / 2 members may be, for example, substantially rectangular in shape.

[0062] For example, a long λ / 2 member having Re(550) in the range of Hs ± 3.2 nm can be obtained by preparing a wide and long λ / 2 member (mother λ / 2 member), slitting the mother λ / 2 member along its longitudinal direction and, if necessary, along its width direction to obtain a plurality of slit λ / 2 members, obtaining Re(550) for the slit λ / 2 members, and selecting a slit λ / 2 member having Re(550) in the range of Hs ± 3.2 nm.

[0063] For example, a single-wafer λ / 2 member having Re(550) within the range of Hs ± 3.2 nm can be obtained by preparing a mother λ / 2 member, slitting the mother λ / 2 member along the longitudinal direction and, if necessary, along the width direction to obtain multiple slit λ / 2 members, punching out the slit λ / 2 members so that the angle between each side and the slow axis is a predetermined angle to obtain multiple single-wafer λ / 2 members, obtaining Re(550) for the single-wafer λ / 2 members, and selecting a single-wafer λ / 2 member having Re(550) within the range of Hs ± 3.2 nm.

[0064] Preparing the mother λ / 2 member may include selecting a wide and long λ / 2 member in which the variation of Re(550) in the width direction is, for example, 10 nm or less, preferably 7 nm or less. The width of the mother λ / 2 member may be, for example, 500 mm to 1500 mm, or for example, 900 mm to 1200 mm. The length of the mother λ / 2 member may be, for example, 100 m to 2000 m, or for example, 500 m to 1000 m.

[0065] The Re(550) of elongated and sheet-shaped λ / 2 members can be determined using the same method as for the Re(550) of elongated and sheet-shaped λ / 4 members.

[0066] [Step III] In Step III, the λ / 4 members prepared in Step I are divided into two groups: Group A1, which has Re(550) of Qsnm or greater than or greater than Qsnm, and Group A2, which has Re(550) of Qsnm or less than or less than Qsnm. λ / 4 members whose Re(550) is Qs may be classified into either Group A1 or Group A2. For example, λ / 4 members whose Re(550) is Qs may be classified to belong to only one of the two groups, or they may be randomly classified into both groups.

[0067] According to process III, λ / 4 members having Re(550) that deviates above Qs and λ / 4 members having Re(550) that deviates below Qs can be classified into separate groups.

[0068] [Process IV] In Process IV, the λ / 2 members prepared in Process II are divided into two groups: Group B1, which has Re(550) of Hsnm or greater than or greater than Hsnm, and Group B2, which has Re(550) of Hsnm or less than or less than Hsnm. λ / 2 members whose Re(550) is Hs may be classified into either Group B1 or Group B2. For example, λ / 2 members whose Re(550) is Hs may be classified to belong to only one of the two groups, or they may be randomly classified into both groups.

[0069] According to process IV, λ / 2 members having Re(550) that deviates above Hs and λ / 2 members having Re(550) that deviates below Hs can be classified into separate groups.

[0070] [Step V] In Step V, the first phase difference member and the second phase difference member are manufactured by any of the methods (i) to (iv) described above. This makes it possible to obtain a first phase difference member including a combination of a λ / 4 member and a λ / 2 member having both upper runout (upper runout set) or a combination of a λ / 4 member and a λ / 2 member having both lower runout (lower runout set), as shown in Table 1; and a second phase difference member including a combination of a λ / 4 member and a λ / 2 member having both upper runout (upper runout set) or a combination of a λ / 4 member and a λ / 2 member having both lower runout (lower runout set).

[0071]

[0072] By manufacturing a display system using the two types of first phase difference members and second phase difference members obtained in this way, a display system described in Section A, specifically a display system that satisfies any of (a) to (d) above, and also satisfies the relationships 0 ≤ |Q1 - Q2| ≤ 7 and 0 ≤ |H1 - H2| ≤ 6.4, can be efficiently manufactured. Furthermore, in the resulting display system, the deviation of Re(550) of each λ / 4 member and λ / 2 member from the reference Re(550) is kept within a predetermined range.

[0073] For example, the above display system can be manufactured by separately preparing member A including a first phase difference member (for example, a member in which a display element and a first phase difference member are integrated) and member B including a second phase difference member (for example, a member in which a first lens part and a second phase difference member are integrated), and assembling them together with other members. In this case, by assembling member A made using the first phase difference member of the upper set or the first phase difference member of the lower set, and member B made using the second phase difference member of the upper set or the second phase difference member of the lower set, a display system can be obtained that satisfies any of (a) to (d) and the relationships 0 ≤ |Q1 - Q2| ≤ 7 and 0 ≤ |H1 - H2| ≤ 6.4, as shown in Table 2.

[0074] According to the above manufacturing method, matching the in-plane phase difference of the first phase difference member (more specifically, the in-plane phase difference between the first λ / 4 member and the first λ / 2 member) and the in-plane phase difference of the second phase difference member (more specifically, the in-plane phase difference between the second λ / 4 member and the second λ / 2 member) during assembly can be omitted. Furthermore, the occurrence of defective inventory of the first phase difference member and / or the second phase difference member in the event of a matching failure can be prevented.

[0075] The first phase difference member and the second phase difference member can each be manufactured by any suitable method. The first phase difference member can be manufactured by laminating a first λ / 4 member and a first λ / 2 member with an adhesive layer in between. The second phase difference member can be manufactured by laminating a second λ / 4 member and a second λ / 2 member with an adhesive layer in between. A tack layer or adhesive layer is preferably used as the adhesive layer.

[0076] C. Method for Manufacturing a Phase Difference Member Set According to another aspect of the present invention, a method for manufacturing a set of a first phase difference member and a second phase difference member used in the display system described in Section A is provided. The above manufacturing method includes steps I to V described in Section B.

[0077] 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.

[0078] (1) Thickness Thickness of 10 μm or less was measured using a scanning electron microscope (JEOL Ltd., product name "JSM-7100F"). Thickness exceeding 10 μm was measured using a digital micrometer (Anritsu Corporation, product name "KC-351C"). (2) Phase difference value Phase difference / elliptic polarization measuring device (Oji Instruments Co., Ltd., product names "KOBRA-HBR" and "KOBRA-HBPR") was used to measure the phase difference value at a predetermined wavelength at 23°C. (3) Transmittance and degree of polarization of polarizing material Single transmittance Ts, parallel transmittance Tp, and orthogonal transmittance Tc of the polarizing material were measured using a spectrophotometer (Otsuka Electronics Co., Ltd., "LPF-200"). These Ts, Tp, and Tc are Y values ​​measured using a 2-degree field of view (C light source) according to JIS Z8701 and corrected for luminous sensitivity. The degree of polarization of the polarizing member was determined from the obtained Tp and Tc values ​​using the following formula: Degree of polarization (%) = {(Tp - Tc) / (Tp + Tc)} １／２ ×100

[0079] [Manufacturing Example 1: λ / 4 Member] A commercially available long resin film mainly composed of a cycloolefin polymer (manufactured by JSR Corporation, trade name "Arton (R5000)", thickness: 130 μm, glass transition temperature: 135°C) was used. A 60 μm thick shrinkable film (manufactured by Toray Industries, trade name "Trefan BO2873") was bonded to both sides of the film via an acrylic adhesive layer (thickness: 15 μm), and the free end was subjected to uniaxial stretching at a stretching temperature of 149°C to 151°C and a stretching ratio of 1.23 to 1.24 times. As a result, λ / 4 members A to I with different Re(550) values ​​were obtained. The Re(550) values ​​of λ / 4 members A to I are shown in Table 3. λ / 4 members A to I exhibited refractive index characteristics nx > nz > ny, the Nz coefficient was 0.5, and the thickness was 37 μm to 39 μm. Furthermore, the Re(450) / Re(550) values ​​for λ / 4 members A to I were all 1.004, indicating an approximately flat dispersion wavelength characteristic.

[0080]

[0081] [Manufacturing Example 2: λ / 2 Members] λ / 2 members A to C were obtained in the same manner as in Manufacturing Example 1, except that the stretching temperature was changed to 153.5°C to 155.5°C and the stretching ratio to 1.31 to 1.32 times, each having different Re(550) values. The Re(550) values ​​of λ / 2 members A to C are shown in Table 4. λ / 2 members A to C exhibited refractive index characteristics of nx > nz > ny, with an Nz coefficient of 0.5 and a thickness of 74 μm to 76 μm. Furthermore, the Re(450) / Re(550) ratio of λ / 2 members A to C was 1.004 for all of them, indicating approximately flat dispersion wavelength characteristics.

[0082]

[0083] [Manufacturing Example 3: Absorbing Polarizing Member] An amorphous isophthalic copolymer polyethylene terephthalate film (thickness: 100 μm) with a long length and a Tg of approximately 75°C was used as the thermoplastic resin substrate, 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 a mixture of 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 added, in water. The PVA aqueous solution was applied to the corona-treated surface of the resin substrate and dried at 60°C to form a PVA-based resin layer with a thickness of 13 μm, thereby producing a laminate. The obtained laminate was uniaxially stretched 2.4 times in the longitudinal direction (longitudinal direction) in an oven at 130°C (air-assisted stretching treatment). 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, it was immersed for 60 seconds in a staining bath at a liquid temperature of 30°C (a 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, it 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 uniaxially stretched between rolls with different peripheral speeds while 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, so that the total stretching ratio in the longitudinal direction was 5.5 times (water stretching treatment). After that, 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). After that, while drying in an oven maintained at approximately 90°C, it was brought into contact with a heated SUS 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 the resin substrate.A cycloolefin resin film (thickness: 25 μm) was bonded to the surface of the obtained absorbing 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 yielded an absorbing polarizing member A having a cycloolefin resin film / absorbing polarizing film structure. The transmittance (Ts) of the absorbing polarizing member A was 43.4%, and the degree of polarization was 99.993%.

[0084] [Manufacturing Example 4: Reflective Polarizing Component] Nitto Denko's reflective polarizing film "APCF" was used as reflective polarizing component A.

[0085] [Manufacturing Example 5: Third Phase Difference Member] In the same manner as in Manufacturing Example 2, a phase difference film (third phase difference member A) with a Re(550) of 271 nm and a thickness of 75 μm was obtained. Third phase difference member A exhibited refractive index characteristics of nx > nz > ny, and the Nz coefficient was 0.5. In addition, the Re(450) / Re(550) of third phase difference member A was 1.004, showing approximately flat dispersion wavelength characteristics.

[0086] [Experimental Example 1: Direct Ghost Evaluation 1] For the display system shown in Figure 1 (Qs = 135 nm, Hs = 270 nm), an optical path model was created showing the light path from the polarizing member that may be included in the display element to the light that enters the reflective section. Specifically, a first phase difference member and a second phase difference member were fabricated so that they correspond to combinations 1 to 8 of λ / 4 member and λ / 2 member shown in Table 5. Next, the obtained first phase difference member and second phase difference member, reflective polarizing member A, absorbing polarizing member A, and third phase difference member A were laminated with an adhesive layer or tack layer in between to create a laminate with the laminate configuration and axis angle shown in Table 6. The absorbing polarizing member A adjacent to the third phase difference member A of the above laminate corresponds to a polarizing member that may be included in the display element.

[0087]

[0088] The above laminate was placed on a backlight (manufactured by ITEC Systems Co., Ltd.), and light was incident from the side of the absorbing polarizing member A adjacent to the third phase difference member A using a UV constant current controlled power supply (scale: COARSE: 2 / FINE: 8). The brightness of the surface of the absorbing polarizing member A adjacent to the reflective polarizing member A was measured using a conoscope (manufactured by Autoronic Co., Ltd.). Brightness measurements were taken a total of 72 times at polar angles of 60° and azimuth angles from 0° to 355° in 5° increments, and the average value was calculated. The results are shown in Figure 3. The low brightness indicates that direct ghosting is suppressed.

[0089] As shown in Figure 3, direct ghosting was suppressed more in the laminates of combinations 1 to 7 than in the laminate of combination 8.

[0090] [Experimental Example 2: Double Bounce Evaluation 1] For the display system shown in Figure 1 (Qs = 135 nm, Hs = 270 nm), an optical path model was created showing the light emitted through a polarizing member that may be included in the display element, reflected twice by a reflective polarizing member, and then incident on the reflective portion. Specifically, a laminate with the laminate configuration and axial angle shown in Table 7 was created by laminating the first and second phase difference members of combinations 1 to 8 of λ / 4 members and λ / 2 members shown in Table 5, a reflective polarizing member A, an absorptive polarizing member A, and a third phase difference member A via an adhesive layer or tack layer. The absorptive polarizing member A adjacent to the third phase difference member A of the above laminate corresponds to a polarizing member that may be included in the display element.

[0091]

[0092] The above laminate was placed on a backlight (manufactured by ITEC Systems Co., Ltd.), and light was incident from the side of the absorbing polarizing member A adjacent to the third phase difference member A using a UV constant current controlled power supply (scale: COARSE: 2 / FINE: 8). The brightness of the surface of the absorbing polarizing member A adjacent to the reflective polarizing member A was measured using a conoscope (manufactured by Autoronic Co., Ltd.). Brightness measurements were taken a total of 72 times at polar angles of 60° and azimuth angles from 0° to 355° in 5° increments, and the average value was calculated. The results are shown in Figure 3. The low brightness indicates that double bounce is suppressed.

[0093] As shown in Figure 3, the laminates of combinations 1-4 and 6-8 exhibited more suppressed double bounce than the laminate of combination 5. In particular, the laminates of combinations 1, 3, and 7 showed excellent double bounce suppression effects.

[0094] From Experimental Examples 1 and 2, it was confirmed that even when using λ / 4 members or λ / 2 members having in-plane phase differences that deviate from the reference in-plane phase difference, both direct ghosting and double bounce can be suppressed according to the configurations of combinations 2, 3, 6, and 7. In combinations 6 and 7, the first λ / 4 member and the first λ / 2 member constituting the first phase difference member, and the second λ / 4 member and the second λ / 2 member constituting the second phase difference member, all have Re(550) that is greater than or less than the reference in-plane phase difference. In combinations 2 and 3, either the set of the first λ / 4 member and the first λ / 2 member constituting the first phase difference member, or the set of the second λ / 4 member and the second λ / 2 member constituting the second phase difference member, has Re(550) that is greater than the reference in-plane phase difference, and the other set has Re(550) that is less than the reference in-plane phase difference.

[0095] [Experimental Example 3: Direct Ghost Evaluation 2] A laminate (i.e., a laminate with the laminate configuration and axial angle shown in Table 6) was fabricated in the same manner as in Experimental Example 1, except that the first and second phase difference members were fabricated to be combinations 3-1 to 3-4 of λ / 4 members and λ / 2 members shown in Table 8.

[0096] In configurations 3-1 and 3-2, the Re(550) of the first λ / 4 member matches the Re(550) of the second λ / 4 member, while the Re(550) of the first λ / 2 member does not match the Re(550) of the second λ / 2 member. In configurations 3-3 and 3-4, the Re(550) of the first λ / 2 member matches the Re(550) of the second λ / 2 member, while the Re(550) of the first λ / 4 member does not match the Re(550) of the second λ / 4 member. For the laminates with the above configurations, the luminance was measured in the same manner as in Experimental Example 1, and the average value was calculated. The results are shown in Figure 4, along with the results for configurations 1, 3, and 8 in Experimental Example 1.

[0097] As shown in Figure 4, in configurations 3-1 and 3-2, where the Re(550) of the first λ / 2 member and the Re(550) of the second λ / 2 member do not match, direct ghosting was suitably suppressed. On the other hand, in configurations 3-3 and 3-4, where the Re(550) of the first λ / 4 member and the Re(550) of the second λ / 4 member do not match, the direct ghosting suppression effect was small.

[0098] [Experimental Example 4: Double Bounce Evaluation 2] A laminate (i.e., a laminate with the laminate configuration and axial angle shown in Table 7) was fabricated in the same manner as in Experimental Example 2, except that the first and second phase difference members of combinations 3-1 to 3-4 of the λ / 4 member and λ / 2 member shown in Table 8 were used.

[0099] The brightness of the resulting laminate was measured in the same manner as in Experimental Example 2, and the average value was calculated. The results are shown in Figure 4, along with the results for configurations 1, 3, and 8 in Experimental Example 2.

[0100] As shown in Figure 4, similar levels of brightness were observed in combinations 1, 3, 8, and 3-1 to 3-4.

[0101] Experimental Examples 3 and 4 suggest that the difference in in-plane phase difference between the first λ / 4 member and the second λ / 4 member can have a greater impact on direct ghosting and double bounce than the difference in in-plane phase difference between the first λ / 2 member and the second λ / 2 member.

[0102] [Experimental Example 5: Direct Ghost Evaluation 3] Laminates (i.e., laminates with the laminate configuration and axial angle shown in Table 6) were fabricated in the same manner as in Experimental Example 1, except that first and second phase difference members were used, which were fabricated to be combinations 3-5, 3-6, and 3-7 of λ / 4 members and λ / 2 members as shown in Table 9. In configurations 3-5, 3-6, and 3-7, the difference between Re (550) of the first λ / 4 member and the second λ / 4 member and the in-plane phase difference Qs (135 nm) is 4 nm, 3.5 nm, and 3 nm, respectively. In all configurations, the Re (550) of the first λ / 2 member and the second λ / 2 member and the in-plane phase difference Hs (270 nm) are in agreement.

[0103]

[0104] The brightness of the resulting laminate was measured in the same manner as in Experimental Example 1, and the average value was calculated. The results, along with the results for combinations 1, 3, 8, and 3-4 in Experimental Examples 1 and 3, are shown in Figure 5.

[0105] As shown in Figure 5, when the Re(550) of the first λ / 4 member and the second λ / 4 member do not coincide with the in-plane phase difference Qs, it can be seen that a direct ghost suppression effect can be suitably obtained even if the difference between Q1 and Q2 is 7 nm, as long as the deviation from Qs is within ±3.5 nm.

[0106] [Experimental Example 6: Double Bounce Evaluation 3] A laminate (i.e., a laminate with the laminate configuration and axial angle shown in Table 7) was fabricated in the same manner as in Experimental Example 2, except that the first and second phase difference members of combinations 3-5, 3-6, and 3-7 of the λ / 4 and λ / 2 members shown in Table 9 were used.

[0107] The brightness of the obtained laminate was measured in the same manner as in Experimental Example 2, and the average value was calculated. The results, along with the results for combinations 1, 3, 8, and 3-4 in Experimental Examples 2 and 4, are shown in Figure 5.

[0108] As shown in Figure 5, similar levels of brightness were observed in configurations 1, 3, 8, and 3-4 to 3-7.

[0109] 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.

[0110] The method for managing optical laminates according to an embodiment of the present invention can be suitably used, for example, in the manufacture of display systems such as VR goggles.

[0111] 2 Display system, 12 Display element, 14 Reflective part, 14a Reflective polarizing member, 16 First lens part, 18 Half mirror, 20 First phase difference member, 20Q First λ / 4 member, 20H First λ / 2 member, 22 Second phase difference member, 22Q Second λ / 4 member, 22H Second λ / 2 member, 24 Second lens part

Claims

1. A method for manufacturing a display system that displays an image to a user, comprising: a display element having a display surface that emits light representing an image forward via a polarizing member; a reflective polarizing member disposed in front of the display element and reflecting light emitted from the display element; a first lens portion disposed in 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 first phase difference member disposed in the optical path between the display element and the half mirror and including a first λ / 4 member and a first λ / 2 member; and a second phase difference member disposed in the optical path between the half mirror and the reflective polarizing member and including a second λ / 4 member and a second λ / 2 member, wherein the in-plane phase difference of the first λ / 4 member and the second λ / 4 member is Q nm. The first λ / 2 member and the second λ / 2 member have a reference in-plane phase difference of H nm, and a plurality of λ / 4 members have an in-plane phase difference such that the difference from Q nm is within a predetermined range. The plurality of λ / 2 members have an in-plane phase difference such that the difference from H nm is within a predetermined range. The λ / 4 members are divided into group A1 having an in-plane phase difference of Q nm or more or greater than Q nm and group A2 having an in-plane phase difference of Q nm or less or less than Q nm. The λ / 2 members are divided into group B1 having an in-plane phase difference of H nm or more or greater than H nm and group B2 having an in-plane phase difference of H nm or less or less than H nm. The first phase difference member and the second phase difference member are manufactured by any of the following methods (i) to (iv). (i) The first phase difference member is manufactured using a λ / 4 member selected from group A1 and a λ / 2 member selected from group B1, and the second phase difference member is manufactured using a λ / 4 member selected from group A1 and a λ / 2 member selected from group B1, (ii) The first phase difference member is manufactured using a λ / 4 member selected from group A2 and a λ / 2 member selected from group B2, and the second phase difference member is manufactured using a λ / 4 member selected from group A2 and a λ / 2 member selected from group B2,A manufacturing method comprising: (iii) manufacturing the first phase difference member using a λ / 4 member selected from group A1 and a λ / 2 member selected from group B1, and manufacturing the second phase difference member using a λ / 4 member selected from group A2 and a λ / 2 member selected from group B2; (iv) manufacturing the first phase difference member using a λ / 4 member selected from group A2 and a λ / 2 member selected from group B2, and manufacturing the second phase difference member using a λ / 4 member selected from group A1 and a λ / 2 member selected from group B1.

2. The in-plane phase difference Re(550) of the first λ / 4 member and the second λ / 4 member is Qs nm, and the in-plane phase difference Re(550) of the first λ / 2 member and the second λ / 2 member is Hs nm. A plurality of λ / 4 members are prepared, each having Re(550) within the range of Qs ± 3.5 nm. A plurality of λ / 2 members are prepared, each having Re(550) within the range of Hs ± 3.2 nm. The λ / 4 members are divided into group A1, which has Re(550) greater than or equal to Qs nm, and group A2, which has Re(550) less than or equal to Qs nm. The manufacturing method according to claim 1, comprising: dividing the λ / 2 members into a group B1 having Re(550) of Hsnm or greater or greater than Hsnm and a group B2 having Re(550) of Hsnm or less or less than Hsnm; and manufacturing the first phase difference member and the second phase difference member by any of the methods (i) to (iv) above.

3. The manufacturing method according to claim 2, wherein preparing a plurality of λ / 4 members having Re(550) in the range of Qs ± 3.5 nm includes preparing a plurality of λ / 4 members having Re(550) in the range of Qs × 0.975 to Qs × 1.

025.

4. The manufacturing method according to claim 2, wherein preparing a plurality of λ / 2 members having Re(550) in the range of Hs ± 3.2 nm includes preparing a plurality of λ / 2 members having Re(550) in the range of Hs × 0.99 to Hs × 1.

01.

5. The manufacturing method according to claim 1, wherein the Nz coefficients of the first λ / 4 member, the second λ / 4 member, the first λ / 2 member, and the second λ / 2 member are each 0.46 to 0.

54.

6. The manufacturing method according to claim 1, wherein the Re(450) / Re(550) ratio of the first λ / 4 member, the second λ / 4 member, the first λ / 2 member, and the second λ / 2 member is 1.05 or less.

7. The manufacturing method according to claim 1, wherein the angle between the slow axis of the first λ / 4 member and the slow axis of the first λ / 2 member is within the range of 60° ± 5°.

8. The manufacturing method according to claim 1, wherein the angle between the slow axis of the second λ / 4 member and the slow axis of the second λ / 2 member is within the range of 60° ± 5°.

9. The manufacturing method according to claim 1, wherein the angle between the slow axis of the first λ / 4 member and the slow axis of the second λ / 4 member is 0° to 5°.

10. The manufacturing method according to claim 1, wherein the angle between the slow axis of the first λ / 2 member and the slow axis of the second λ / 2 member is 0° to 5°.

11. A display system for displaying an image to a user, comprising: a display element having a display surface that emits light representing an image forward via a polarizing member; a reflective polarizing member disposed in front of the display element and reflecting light emitted from the display element; a first lens portion disposed in 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 first phase difference member disposed in the optical path between the display element and the half mirror and including a first λ / 4 member and a first λ / 2 member; and a second phase difference member disposed in the optical path between the half mirror and the reflective polarizing member and including a second λ / 4 member and a second λ / 2 member. A display system that satisfies the relationships 0 ≤ |Q1 - Q2| ≤ 7 and 0 ≤ |H1 - H2| ≤ 6.4, where the Re(550) of the first λ / 4 member, the first λ / 2 member, the second λ / 4 member, and the second λ / 2 member are Q1 nm, H1 nm, Q2 nm, and H2 nm, respectively.

12. The display system according to claim 11, satisfying the relationships 3.2 ≤ |Q1 - Q2| ≤ 7 and 0 ≤ |H1 - H2| ≤ 6.4.

Images