Method of manufacturing optical plate

Abstract

To provide an optical plate capable of forming an aerial image with high image quality.SOLUTION: The method of manufacturing an optical plate which includes a first plate having a plurality of projections on a first principal plane; a second plate having a plurality of projections on a second principal plane; and an adhesive layer provided between the first principal plane and the second principal plane includes a process for applying an adhesive agent on the first principal plane of the first plate, a process for partially hardening the adhesive agent, and a process for pressing an intermediate plate body with the second plate put on the adhesive agent and entirely hardening the adhesive agent to form the adhesive layer.SELECTED DRAWING: Figure 7

Description

[Technical Field]

[0001] The present invention relates to a method for manufacturing an optical plate. [Background technology]

[0002] Conventionally, an aerial imaging device has been known that focuses an image displayed on a display unit of an image display device on an imaging plane in the air and displays the image (hereinafter referred to as an aerial image) on the imaging plane, as disclosed in Patent Document 1. Such an aerial imaging device has a transparent imaging unit that focuses an image displayed on the display unit as an aerial image. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2014-67071 Summary of the Invention [Problem to be solved by the invention]

[0004] In the aerial imaging device described above, a high-quality aerial image is desired.

[0005] An object of the present invention is to provide an optical plate capable of forming a high-quality aerial image. [Means for solving the problem]

[0006] One aspect of the method for manufacturing an optical plate according to the present invention is to a first plate having a plurality of ridges on a first main surface; a second plate having a plurality of ridges on a second main surface; a bonding layer provided between a first main surface and a second main surface, applying an adhesive to a first major surface of a first plate; partially curing the adhesive; and a step of pressing the intermediate plate body, in which the second plate is placed on top of the adhesive, to harden the adhesive overall to form an adhesive layer. [Effects of the Invention]

[0007] According to the present invention, an optical plate capable of forming a high-quality aerial image can be provided. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a schematic cross-sectional view of a non-contact input device according to a first embodiment of the present invention. [Figure 2] FIG. 2 is a functional block diagram showing the functional configuration of the non-contact input device. [Figure 3] FIG. 3 is a schematic plan view of the lower plate. [Figure 4] FIG. 4 is a schematic cross-sectional view of the lower plate taken along line C1-C1 in FIG. [Figure 5] FIG. 5 is a schematic cross-sectional view showing one of the protrusions. [Figure 6] FIG. 6 is a schematic cross-sectional view of the imaging unit. [Figure 7] FIG. 7 is a flowchart showing steps in a method for manufacturing an optical plate. [Figure 8a] FIG. 8a is a schematic diagram showing steps in a method for manufacturing an optical plate. [Figure 8b] FIG. 8b is a schematic diagram showing steps in a method for manufacturing an optical plate. [Figure 8c] FIG. 8c is a schematic diagram showing steps in a method for manufacturing an optical plate. [Figure 8d] FIG. 8d is a schematic diagram showing steps in the method for manufacturing an optical plate. [Figure 8e] FIG. 8e is a schematic diagram showing steps in a method for manufacturing an optical plate. [Figure 8f] FIG. 8f is a schematic diagram showing steps in a method for manufacturing an optical plate. [Figure 9] FIG. 9 is a flowchart showing steps of a method for manufacturing an optical plate according to the second embodiment of the present invention. [Figure 10a] FIG. 10a is a schematic diagram showing steps in a method for manufacturing an optical plate. [Figure 10b] FIG. 10b is a schematic diagram showing steps in a method for manufacturing an optical plate. [Figure 10c] FIG. 10c is a schematic diagram showing steps in a method for manufacturing an optical plate. [Figure 10d] FIG. 10d is a schematic diagram showing steps in a method for manufacturing an optical plate. [Figure 10e] FIG. 10e is a schematic diagram showing steps in a method for manufacturing an optical plate. [Figure 10f] FIG. 10f is a schematic diagram showing steps in a method for manufacturing an optical plate. DETAILED DESCRIPTION OF THE INVENTION

[0009] An example of a method for manufacturing an optical plate according to the present invention will be described in detail below with reference to the drawings. Note that the method for manufacturing an optical plate described below is an example of a method for manufacturing an optical plate according to the present invention, and the present invention is not limited to the embodiments described below.

[0010] [Embodiment 1] First, before describing the method for manufacturing an optical plate according to this embodiment, the configuration of a non-contact input device 1 incorporating an optical plate (imaging unit 4 in this embodiment) manufactured by the method for manufacturing an optical plate according to this embodiment will be described with reference to Figures 1 to 6. The non-contact input device 1 corresponds to an example of an aerial imaging device.

[0011] 1 is a schematic cross-sectional view of a non-contact input device 1. The non-contact input device 1 is a device equipped with a so-called aerial display, which can project information and images into the air.

[0012] Such a non-contact input device 1 is used as a terminal for a user U to input information or a terminal for a user U to obtain information in various places (stores, public facilities, medical facilities, factories, etc.).

[0013] Specifically, the non-contact input device 1 may be used as an accounting terminal or a reception terminal, or as an operation input terminal for inputting operation inputs to various devices.

[0014] In the following explanation, when explaining the structure of the non-contact input device 1 and each of the components that make up the non-contact input device 1, a Cartesian coordinate system (X, Y, Z) shown in each drawing may be used. The X direction corresponds to the front-to-rear direction of the non-contact input device 1. The positive side of the X direction corresponds to the front side of the non-contact input device 1. The negative side of the X direction corresponds to the rear side of the non-contact input device 1.

[0015] Moreover, the Y direction corresponds to the left-right direction and width direction of the non-contact input device 1. The + side of the Y direction corresponds to the left side when the non-contact input device 1 is viewed from the front of the non-contact input device 1. The - side of the Y direction corresponds to the right side when the non-contact input device 1 is viewed from the front of the non-contact input device 1.

[0016] The Z direction corresponds to the up-down direction of the non-contact input device 1. The positive Z direction corresponds to the upper side of the non-contact input device 1. The negative Z direction corresponds to the lower side of the non-contact input device 1.

[0017] The non-contact input device 1 includes a housing 2, a display unit 3, an imaging unit 4, an input detection unit 5 (see FIG. 2), and a control unit 6.

[0018] Non-contact input device 1 according to this embodiment is a so-called horizontally placed non-contact input device. In the case of a horizontally placed non-contact input device, aerial image G1 is displayed above non-contact input device 1, as shown in Fig. 1. Note that the non-contact input device is not limited to a horizontally placed non-contact input device.

[0019] The non-contact input device may be a so-called vertically-placed non-contact input device. A vertically-placed non-contact input device has a configuration similar to that of non-contact input device 1 shown in Fig. 1 rotated 90° clockwise in Fig. 1. In the case of a vertically-placed non-contact input device, aerial image G1 is displayed in front of non-contact input device 1.

[0020] The housing 2 is box-shaped and is a member for housing or supporting each element that constitutes the non-contact input device 1. In this embodiment, the housing 2 is a rectangular parallelepiped that is long in the front-rear direction.

[0021] However, the shape of the housing is not limited to the shape of the housing 2 of this embodiment. The shape of the housing may be determined appropriately depending on the environment in which the non-contact input device 1 is installed. The shape of the housing 2 is not limited to a box shape. The shape of the housing 2 may be various shapes that can accommodate or support each element that constitutes the non-contact input device 1.

[0022] The display unit 3 may be, for example, any of various displays that display images (for example, a liquid crystal display). The display unit 3 is supported by the housing 2 via a support 21. The display unit 3 faces diagonally upward and rearward toward the imaging unit 4, which will be described later.

[0023] Specifically, the display unit 3 is supported by the support part 21 in a state in which the front end of the display unit 3 is tilted at a predetermined angle θ1 in a direction approaching the imaging unit 4 (described later) with respect to an imaginary line α1 parallel to the horizontal direction. In the present embodiment, the predetermined angle θ1 is 45°.

[0024] The display unit 3 has a display surface 30 that emits light for an image, and a main body 31 that supports the display surface 30.

[0025] The light of the display image displayed on display surface 30 is focused as aerial image G1 on imaging surface S by imaging unit 4, which will be described later. Aerial image G1 is an example of a real image. Imaging surface S is a virtual region that exists in the air outside housing 2.

[0026] Of the light of the display image displayed by display surface 30, the light that is imaged as aerial image G1 on imaging surface S by imaging unit 4 is sometimes referred to as light to be imaged. The light of the display image displayed by display surface 30 also includes light other than the light that is imaged as aerial image G1 on imaging surface S by imaging unit 4 (hereinafter, sometimes referred to as light not to be imaged).

[0027] The imaging plane S is a virtual area that exists at a position that is plane-symmetrical to the display unit 3 with respect to the imaging unit 4 (in other words, the virtual line α2). The virtual line α2 is a virtual line that passes through the imaging unit 4 and is parallel to the horizontal direction. The virtual line α2 also passes through the imaging unit 4 and indicates a plane that is parallel to the imaging unit 4.

[0028] Specifically, the imaging surface S is a virtual area inclined at a predetermined angle θ2 with respect to a virtual line α3 parallel to the horizontal direction in a direction in which the front end of the imaging surface S approaches the imaging unit 4. In the present embodiment, the predetermined angle θ2 is 45°.

[0029] The display operation of the display unit 3 is controlled by the control unit 6, which will be described later. The control process of the display unit 3 by the control unit 6 will be described later.

[0030] 1, the imaging unit 4 is a plate-shaped member. The imaging unit 4 corresponds to an example of an optical plate. In other words, the imaging unit 4 is manufactured by the method for manufacturing an optical plate according to this embodiment.

[0031] Imaging unit 4 is arranged parallel in the front-rear and left-right directions. Imaging unit 4 images the image displayed on display unit 3 in an aerial image region on imaging plane S as aerial image G1.

[0032] The imaging unit 4 has a lower plate 4a and an upper plate 4b stacked one on top of the other. The imaging unit 4 also has an adhesive layer 4c between the lower plate 4a and the upper plate 4b. The lower plate 4a and the upper plate 4b are connected by the adhesive layer 4c.

[0033] The lower plate 4a and the upper plate 4b have almost the same configuration. The configuration of the lower plate 4a will be described below. For the configuration of the upper plate 4b, the description of the lower plate 4a may be used as appropriate.

[0034] (lower plate) The lower plate 4a is an example of a first plate, and includes a main body portion 41 and a light reflecting portion .

[0035] The main body 41 is made of a transparent resin and has a rectangular plate shape in the plan view shown in Fig. 3. Fig. 3 is a schematic plan view of the lower plate 4a and the adhesive layer 4c.

[0036] The shape in plan view refers to the shape when the lower plate 4a is viewed from above. Also, Fig. 4 is a schematic cross-sectional view of the lower plate 4a and adhesive layer 4c taken along line C1-C1 in Fig. 3. For ease of explanation, hatching indicating a cross section has been omitted in Fig. 4.

[0037] The resin constituting the main body 41 is preferably any one of ultraviolet curing resin, thermosetting resin, two-component curing resin, and room temperature curing resin. Examples of ultraviolet curing resins include (meth)acrylates such as urethane (meth)acrylate, (meth)acrylate having a polyisoprene skeleton, (meth)acrylate having a polybutadiene skeleton, and (meth)acrylate monomers.

[0038] Furthermore, the resin constituting the main body 41 may be a thermoplastic resin such as polymethyl methacrylate (PMMA: acrylic resin), amorphous fluororesin, cycloolefin polymer (COP), optical polycarbonate, fluorene polyester, and polyethersulfone.

[0039] The main body 41 has a plurality of ridges 43 and a plurality of grooves 44 .

[0040] The plurality of ridges 43 are provided on a first surface of the main body portion 41. The first surface of the main body portion 41 corresponds to an example of a first main surface of a first plate.

[0041] Each of the plurality of ridges 43 extends in a first direction (in this embodiment, the first direction is the left-right direction), and the plurality of ridges 43 are aligned in a second direction.

[0042] The second direction is a direction perpendicular to the first direction in a horizontal plane. In this embodiment, the second direction is the front-to-rear direction. The first and second directions are determined according to the arrangement of the imaging unit 4. Therefore, the first direction is not limited to the left-to-right direction. Furthermore, the second direction is not limited to the front-to-rear direction.

[0043] In the main body 41, the surface that faces the first surface in the up-down direction is the second surface. The up-down direction may also be referred to as the third direction.

[0044] The first surface of the main body 41 of the lower plate 4a is the upper surface of the main body 41. The second surface of the main body 41 of the lower plate 4a is the lower surface of the main body 41.

[0045] The multiple ridges 43 have the same configuration. The configuration of one ridge 43 will be described below with reference to Figures 4 and 5. For the configurations of the other ridges 43, the description of the ridges 43 below may be used as appropriate. Figure 5 is a schematic cross-sectional view showing one ridge 43. Hatching indicating a cross section has been omitted in Figure 5.

[0046] As shown in FIG. 5, the protrusion 43 has a vertical surface 431 and an inclined surface 432 .

[0047] The vertical surface 431 is provided on one side surface of the protrusion 43 in the second direction. In the present embodiment, the one side surface of the protrusion 43 in the second direction is a rear side surface of the protrusion 43. The one side surface of the protrusion 43 in the second direction corresponds to an example of a first side surface of the protrusion.

[0048] The vertical surfaces 431 are surfaces parallel to the vertical direction. The vertical surfaces 431 have a height dimension d (hereinafter also referred to as the height dimension d of the ribs 43). The vertical surfaces 431 of adjacent ribs 43 in the second direction are spaced apart by a distance p (hereinafter also referred to as the distance p of the ribs 43).

[0049] The inclined surface 432 is provided on the other side surface of the protrusion 43 in the second direction. In the present embodiment, the other side surface of the protrusion 43 in the second direction is the front side surface of the protrusion 43. The other side surface of the protrusion 43 in the second direction corresponds to an example of the second side surface of the protrusion.

[0050] The inclined surface 432 is a surface inclined with respect to the vertical direction. The angle of inclination of the inclined surface 432 with respect to the vertical direction may be determined appropriately based on the relationship between the height dimension d of the rib projection 43 and the distance p of the rib projection 43. In this embodiment, the inclined surface 432 is a flat surface.

[0051] In this embodiment, the base end edge of the inclined surface 432 of the protrusion 43 (also referred to as the first protrusion 43) is directly connected to the base end edge of the vertical surface 431 of the protrusion 43 (also referred to as the second protrusion 43) provided adjacent to the protrusion 43.

[0052] The grooves 44 are provided between adjacent ridges 43 in the second direction. The cross section of the grooves 44 is a right triangle, as shown in Fig. 4. The grooves 44 extend in the first direction along the ridges 43.

[0053] 5, the light reflecting portion 42 is a metal film. In other words, the light reflecting portion 42 includes a metal layer. Examples of materials that form the light reflecting portion 42 include aluminum and silver.

[0054] The light reflecting portion 42 may be composed of one or more metal layers. When the light reflecting portion 42 is composed of multiple metal layers, the light reflecting portion 42 may include a metal layer composed of at least one of aluminum and silver.

[0055] The light reflecting portion 42 is provided on the vertical surface 431 of the main body portion 41. Such a light reflecting portion 42 is formed by a thin film formation method such as a metal vapor deposition method or a sputtering method. Note that the light reflecting portion 42 is omitted in Fig. 4. The thin film formation method for forming the light reflecting portion 42 may be any of various thin film formation methods.

[0056] (Upper plate) The upper plate 4b has a configuration substantially similar to that of the above-described lower plate 4a. The lower plate 4a and the upper plate 4b having such a configuration are fixed in a vertically overlapping state by an adhesive layer 4c described below.

[0057] Fig. 6 is a schematic cross-sectional view of the imaging unit 4, taken along a line corresponding to the C1-C1 line in Fig. 3. For ease of explanation, hatching indicating a cross section has been omitted in Fig. 6.

[0058] In this embodiment, as shown in Fig. 6, the upper plate 4b is fixed to the lower plate 4a with the first surface on which the ribs 43 are formed facing downward. The first surface of the upper plate 4b and the first surface of the lower plate 4a are fixed together. The first surface of the upper plate 4b corresponds to an example of the second main surface of the second plate.

[0059] In this embodiment, the upper plate 4b is fixed to the lower plate 4a in a state in which the protrusions 43 of the upper plate 4b are perpendicular to the upper plate 4b of the lower plate 4a in plan view.

[0060] (adhesive layer) The adhesive layer 4c is provided between the lower plate 4a and the upper plate 4b and fixes the lower plate 4a and the upper plate 4b together.

[0061] The adhesive contains, for example, an alicyclic epoxy resin, a carbon ring-free cationically polymerizable resin, a tackifier resin, and a photopolymerization initiator. In this embodiment, the cure shrinkage of the adhesive is 5% or less.

[0062] The adhesive contains, for example, an alicyclic epoxy resin, a carbon ring-free cationically polymerizable resin, a tackifier resin, and a photopolymerization initiator.

[0063] (1) Alicyclic epoxy resin The alicyclic epoxy resin is a curable resin (e.g., a thermosetting resin, a photocurable resin, etc.) that has an epoxy group and an aliphatic ring (alicyclic skeleton) but does not have an aromatic ring, and is preferably a photocurable resin (more specifically, ultraviolet curable).

[0064] When the adhesive contains an alicyclic epoxy resin, absorption of light in the visible light region can be suppressed compared to when the adhesive contains an aromatic epoxy resin, and the parallel light transmittance of the cured product of the adhesive, which will be described later, can be reduced.

[0065] The alicyclic epoxy resin is, for example, a polyfunctional (including difunctional) epoxy resin having a plurality of epoxy groups, and is preferably a difunctional epoxy resin having two epoxy groups.

[0066] Examples of alicyclic epoxy resins include polyglycidyl ether-containing alicyclic epoxy resins having multiple glycidyl ether units bonded to an aliphatic ring, and epoxycyclo structure-containing epoxy resins having an epoxy group composed of two adjacent carbon atoms forming an aliphatic ring and one oxygen atom bonded to those two carbon atoms.

[0067] Examples of polyglycidyl ether-containing alicyclic epoxy resins include bifunctional glycidyl ether-containing alicyclic epoxy resins such as hydrogenated bisphenol A diglycidyl ether, hydrogenated bisphenol F diglycidyl ether, hexahydrophthalic acid diglycidyl ester, etc. The polyglycidyl ether-containing alicyclic epoxy resins can be used alone or in combination of two or more.

[0068] Of these alicyclic epoxy resins, epoxy cyclo structure-containing epoxy resins are preferred, and ECH structure-containing epoxy resins are more preferred.

[0069] That is, the alicyclic epoxy resin preferably includes an epoxycyclo structure-containing epoxy resin, more preferably includes an ECH structure-containing epoxy resin, and particularly preferably consists of an ECH structure-containing epoxy resin.

[0070] When the alicyclic epoxy resin contains an epoxycyclo structure-containing epoxy resin (ECH structure-containing epoxy resin), it is possible to reliably reduce the cure shrinkage rate of the adhesive while also reliably imparting excellent light transmittance to the cured product of the adhesive.

[0071] Specific examples of the ECH structure-containing epoxy resins described above include bis(3,4-epoxycyclohexylmethyl)ether, 1,2-bis(3,4-epoxycyclohexan-1-yl)ethane, 2,2-bis(3,4-epoxycyclohexan-1-yl)propane, 3,4-epoxycyclohexylmethyl(3,4-epoxy)cyclohexanecarboxylate, and ε-caprolactone-modified 3′,4′-epoxycyclohexylmethyl 3,4-epoxycyclohexanecarboxylate, with 3,4-epoxycyclohexylmethyl(3,4-epoxy)cyclohexanecarboxylate being preferred.

[0072] Commercially available ECH structure-containing epoxy resins can also be used, such as Celloxide 8000, Celloxide 2021P (epoxy equivalent: 128 to 145 g / eq.), and Celloxide 2081 (all manufactured by Daicel Corporation).

[0073] The content of the alicyclic epoxy resin in the adhesive for optical imaging devices is, for example, 5% by mass or more, preferably 10% by mass or more, more preferably 15% by mass or more, and particularly preferably 17% by mass or more, and for example, 60% by mass or less, preferably 50% by mass or less, and more preferably 30% by mass or less.

[0074] When the content of the alicyclic epoxy resin is within the above range, the content of the other components can be ensured, and the various properties required of the cured product of the adhesive can be ensured in a well-balanced manner. In particular, when the content of the alicyclic epoxy resin is equal to or greater than the above lower limit, the viscosity of the adhesive can be more reliably reduced, and the refractive index of the cured product of the adhesive can be reliably reduced.

[0075] (2) Carbon ring-free cationically polymerizable resin The carbon ring-free cationically polymerizable resin is a cationically polymerizable resin that does not contain a carbon ring (aliphatic ring or aromatic ring), and is preferably a photocurable resin (more specifically, ultraviolet curable).

[0076] Examples of the carbon ring-free cationically polymerizable resin include polyglycidyl ether-containing acyclic epoxy resins, oxetane ring-containing compounds, furan ring-containing compounds, etc. The carbon ring-free cationically polymerizable resins can be used alone or in combination of two or more.

[0077] Among such carbon ring-free cationically polymerizable resins, preferred examples include polyglycidyl ether-containing acyclic epoxy resins and oxetane ring-containing compounds.

[0078] Examples of polyglycidyl ether-containing acyclic epoxy resins include alkylene glycol diglycidyl ether, polyalkylene glycol diglycidyl ether, glycerin triglycidyl ether, pentaerythritol tetraglycidyl ether, dipentaerythritol hexaglycidyl ether, etc. The polyglycidyl ether-containing acyclic epoxy resins can be used alone or in combination of two or more.

[0079] The oxetane ring-containing compound contains, for example, 1 to 5 oxetane rings.

[0080] Examples of oxetane ring-containing compounds include monofunctional oxetane compounds having one oxetane ring, bifunctional oxetane compounds having two oxetane rings, and trifunctional or higher oxetane compounds having three or more oxetane rings.

[0081] Examples of monofunctional oxetane compounds include 3-ethyl-3-hydroxymethyloxetane, 3-(meth)allyloxymethyl-3-ethyloxetane, (3-ethyl-3-oxetanylmethoxy)methylbenzene, 2-ethylhexyl(3-ethyl-3-oxetanylmethyl)ether, ethyldiethylene glycol(3-ethyl-3-oxetanylmethyl)ether, and 3-cyclohexylmethyl-3-ethyloxetane.

[0082] Examples of bifunctional oxetane compounds include 1,4-bis{[(3-ethyl-3-oxetanyl)methoxy]methyl}benzene, 3,3'-(oxybismethylene)bis(3-ethyloxetane), 1,4-bis[(3-ethyl-3-oxetanyl)methoxy]benzene, 1,3-bis[(3-ethyl-3-oxetanyl)methoxy]benzene, 3,7-bis(3-oxetanyl)-5-oxa-nonane, 1,4-bis[(3-ethyl-3-oxetanylmethoxy)methyl]benzene, 1,2-bis[(3-ethyl-3-oxetanylmethoxy)methyl]ethane, 1,2-bis[(3-ethyl-3-oxetanylmethoxy)methyl]propane, ethylene glycol bis(3-ethyl-3-oxetanylmethyl)ether, and dicyclopentenyl bis(3-ethyl-3-oxetanylmethyl)ether.

[0083] Examples of trifunctional or higher functional oxetane compounds include trimethylolpropane tris(3-ethyl-3-oxetanylmethyl) ether, pentaerythritol tris(3-ethyl-3-oxetanylmethyl) ether, pentaerythritol tetrakis(3-ethyl-3-oxetanylmethyl) ether, and dipentaerythritol pentakis(3-ethyl-3-oxetanylmethyl) ether.

[0084] Such oxetane ring-containing compounds can be used alone or in combination of two or more kinds.

[0085] Among such polyglycidyl ether-containing acyclic epoxy resins and oxetane ring-containing compounds, preferably, oxetane ring-containing compounds are used, more preferably, bifunctional oxetane compounds are used, and particularly preferably, 3,3'-(oxybismethylene)bis(3-ethyloxetane) is used.

[0086] That is, the carbon ring-free cationically polymerizable resin preferably contains an oxetane ring-containing compound (bifunctional oxetane compound, 3,3'-(oxybismethylene)bis(3-ethyloxetane)), and more preferably consists of an oxetane ring-containing compound (bifunctional oxetane compound, 3,3'-(oxybismethylene)bis(3-ethyloxetane)).

[0087] Alternatively, commercially available oxetane ring-containing compounds may be used, such as Aron Oxetane OXT-221 and Aron Oxetane OXT-121 (both manufactured by Toagosei Chemical Industry Co., Ltd.).

[0088] The content of the carbon ring-free cationically polymerizable resin in the adhesive for optical imaging devices is, for example, 5% by mass or more, preferably 10% by mass or more, more preferably 15% by mass or more, particularly preferably 17% by mass or more, and particularly preferably 20% by mass or more, and for example, 60% by mass or less, preferably 40% by mass or less, and more preferably 35% by mass or less.

[0089] (3) Tackifying resin The tackifying resin is a thermoplastic resin that does not react with the above-mentioned alicyclic epoxy resin and the above-mentioned carbon ring-free cationically polymerizable resin, and is added to the adhesive as an organic filler.

[0090] The tackifying resin reduces the cure shrinkage of the adhesive and improves the parallel light transmittance of the cured product of the adhesive.

[0091] The softening point of the tackifier resin is, for example, 70°C or more, preferably 90°C or more, and for example, 160°C or less, preferably 140°C or less.

[0092] Examples of tackifying resins include aromatic hydrocarbon resins, unsaturated aliphatic hydrocarbon resins, and saturated aliphatic hydrocarbon resins.

[0093] Aromatic hydrocarbon resins are hydrocarbon resins having an aromatic ring, and examples of aromatic hydrocarbon resins include C9 petroleum resins and terpene phenol resins.

[0094] The unsaturated aliphatic hydrocarbon resin is a hydrocarbon resin having an unsaturated bond but no aromatic ring. Examples of the unsaturated aliphatic hydrocarbon resin include rosin hydrocarbon resin, polyterpene resin, and C5 petroleum resin.

[0095] The saturated aliphatic hydrocarbon resin is a hydrocarbon resin that does not have an unsaturated bond, and includes an alicyclic saturated hydrocarbon resin that has an aliphatic ring.

[0096] Examples of saturated aliphatic hydrocarbon resins include hydrogenated products of the above-mentioned aromatic hydrocarbon resins (specifically, hydrogenated C9 petroleum resins, hydrogenated terpene phenol resins, etc.), and hydrogenated products of the above-mentioned unsaturated aliphatic hydrocarbon resins (specifically, hydrogenated rosin hydrocarbon resins, hydrogenated polyterpene resins, hydrogenated C5 petroleum resins, etc.).

[0097] Such tackifying resins can be used alone or in combination of two or more.

[0098] Among such tackifying resins, preferably, aromatic hydrocarbon resins and saturated aliphatic hydrocarbon resins are used, more preferably, saturated aliphatic hydrocarbon resins are used, particularly preferably, hydrogenated products of unsaturated aliphatic hydrocarbon resins are used, and particularly preferably, hydrogenated rosin hydrocarbon resins are used.

[0099] That is, the tackifier resin preferably contains an aromatic hydrocarbon resin and / or a saturated aliphatic hydrocarbon resin, more preferably contains a saturated aliphatic hydrocarbon resin (a hydrogenated product of an unsaturated aliphatic hydrocarbon resin, a hydrogenated rosin hydrocarbon resin), and particularly preferably consists of a saturated aliphatic hydrocarbon resin (a hydrogenated product of an unsaturated aliphatic hydrocarbon resin, a hydrogenated rosin hydrocarbon resin).

[0100] When the tackifier resin contains a saturated aliphatic hydrocarbon resin (a hydrogenated product of an unsaturated aliphatic hydrocarbon resin, or a hydrogenated rosin hydrocarbon resin), the transparency of the cured adhesive can be reliably improved.

[0101] Commercially available aromatic hydrocarbon resins and saturated aliphatic hydrocarbon resins can also be used. Commercially available aromatic hydrocarbon resins include FTR8100 (manufactured by Mitsui Chemicals, Inc.) and Tamanol 901 (manufactured by Arakawa Chemical Industries, Ltd.). Commercially available saturated aliphatic hydrocarbon resins include Pine Crystal KE-100 (hydrogenated rosin-based hydrocarbon resin, manufactured by Arakawa Chemical Industries, Ltd.) and Quintone A100 (manufactured by Zeon Corporation).

[0102] The content of the tackifier resin in the adhesive for optical imaging devices is 30% by mass or more, preferably 35% by mass or more, more preferably 45% by mass or more, and 70% by mass or less, preferably 66% by mass or less, more preferably 60% by mass or less, and particularly preferably 50% by mass or less.

[0103] When the content of the tackifier resin is within the above range, the content of the other components can be ensured, and the various properties required of the cured product of the adhesive can be ensured in a balanced manner. In particular, when the content of the tackifier resin is equal to or greater than the above lower limit, the cure shrinkage rate of the adhesive can be reduced, and when the content of the tackifier resin is equal to or less than the above upper limit, the parallel light transmittance of the cured product of the adhesive for optical imaging devices can be improved.

[0104] (4) Photopolymerization initiator The photopolymerization initiator is a photoacid generator that generates acid upon irradiation with light, and cures the adhesive upon irradiation with light (for example, ultraviolet light).

[0105] The photopolymerization initiator is not particularly limited, and any known cationic photopolymerization initiator can be used.

[0106] Examples of the cationic photopolymerization initiator include sulfonium salts, phosphonium salts, quaternary ammonium salts, diazonium salts, and iodonium salts, each of which has a counter anion such as AsF6-, SbF6-, PF6-, BF4-, or SbCl6-. These cationic photopolymerization initiators can be used alone or in combination of two or more.

[0107] Such a cationic photopolymerization initiator may be a commercially available product, such as CPI-100P (manufactured by San-Apro Co., Ltd.) or BULESIL PI2074 (manufactured by Solvay).

[0108] (5) Other additives The adhesive may contain, as necessary, other additives such as a known silane coupling agent (e.g., γ-glycidoxypropyltrimethoxysilane), a known leveling agent (e.g., a silicone-based polymer), or a known defoaming agent (e.g., a polyethylene-based defoaming agent).

[0109] The content ratio of each of the silane coupling agent, leveling agent, and antifoaming agent relative to the adhesive for optical imaging devices is, for example, 0.01 mass% or more, preferably 0.05 mass% or more, for example, 10 mass% or less, preferably 3 mass% or less.

[0110] Furthermore, the adhesive may further contain other additives, such as a stabilizer, an organic solvent, a polymerization initiation aid, an antiaging agent, a wettability improver, a surfactant, a plasticizer, an ultraviolet absorber, a preservative, and an antibacterial agent, in an appropriate ratio, as required.

[0111] Light of the display image on the display unit 3 is incident on the imaging unit 4 having the above-described configuration from the direction indicated by arrow A1 in Fig. 1. Hereinafter, the light of the display image incident on the imaging unit 4 may also be referred to as incident light related to the display image.

[0112] In this way, incident light related to the display image is reflected a specified number of times (for example, twice) at imaging unit 4, and is emitted from imaging unit 4 in the direction indicated by arrow A2 in Figure 1. Then, the emitted light related to the display image is focused on imaging surface S as aerial image G1.

[0113] In this way, of the light incident on the imaging unit 4, only the light that has been reflected a specified number of times within the imaging unit 4 (in other words, the light to be imaged) is imaged by the imaging unit 4 on the imaging surface S as an aerial image G1.

[0114] On the other hand, light that is incident on imaging unit 4 and does not undergo a specified number of reflections within imaging unit 4 (in other words, light not to be imaged) is not imaged on imaging surface S by imaging unit 4 as aerial image G1.

[0115] The incident angle of the light to be imaged in the incident light relating to the display image is equal to the tilt angle θ1 with respect to the virtual line α1 (see FIG. 1) of the display unit 3. In this embodiment, the incident angle of the incident light relating to the display image is 45°.

[0116] In addition, the angle of emergence of the light to be imaged in the emergent light for the displayed image is equal to the angle of incidence of the light to be imaged in the incident light for the displayed image. In this embodiment, the angle of emergence of the light to be imaged in the emergent light for the displayed image is 45°.

[0117] Input detection unit 5 (see FIG. 2) detects information (hereinafter referred to as operation input information) related to operation input to aerial image G1 from user U (see FIG. 1). As shown in FIG. 2, input detection unit 5 sends the detected operation input information to control unit 6. Such input detection unit 5 is supported by housing 2.

[0118] Input detection unit 5 is configured with a plurality of sensors (not shown). Input detection unit 5 detects, for example, information relating to a position in aerial image G1 operated by user U (also referred to as position information) as operation input information.

[0119] The position information may be, for example, information about coordinates in the aerial image G1 (also referred to as coordinate information). The coordinate information may be three-dimensional coordinates consisting of coordinates in the X direction, coordinates in the Y direction, and coordinates in the Z direction.

[0120] Input detection unit 5 may also detect information regarding the input depth of a fingertip when user U operates aerial image G1 (also referred to as input depth information). The input depth information may include the distance that user U's fingertip passes through aerial image G1 when user U operates aerial image G1. Input detection unit 5 sends the detected input depth information to control unit 6.

[0121] The above-mentioned operation input information, position information, coordinate information, and input depth information may be collectively referred to as first information.

[0122] The configuration of the input detection unit 5 is not particularly limited. The configuration of the input detection unit 5 may be various configurations that can realize the above-mentioned functions. Furthermore, the location where the input detection unit 5 is provided is also not particularly limited. The input detection unit 5 may be provided in various locations that can realize the above-mentioned functions.

[0123] 2, the control unit 6 controls the operation of the display unit 3. The control unit 6 is supported by the housing 2. The control unit 6 may actually be configured with a CPU, ROM, RAM, HDD, etc. connected via a bus, or may be configured with a one-chip LSI, etc. The control executed by the control unit 6 will be described below.

[0124] Controller 6 controls the display of the aerial image. That is, controller 6 controls the display operation of display unit 3. Specifically, controller 6 controls the display of the aerial image based on information related to an operation input by user U of non-contact input device 1 to aerial image G1.

[0125] Control unit 6 acquires information regarding operation input by user U of non-contact input device 1 to aerial image G1 from input detection unit 5. The information regarding operation input by user U of non-contact input device 1 to aerial image G1 is first information detected by input detection unit 5 (specifically, operation input information, position information, coordinate information, and input depth information).

[0126] (Operation of non-contact input device) The operation of the non-contact input device 1 will now be briefly described.

[0127] When the power of the non-contact input device 1 is turned on, the control unit 6 controls the display operation of the display unit 3. Then, a predetermined image is displayed on the display unit 3. Then, light of the image is emitted from the display unit 3 (specifically, the display surface 30).

[0128] Of the light of the image emitted from the display unit 3 (specifically, display surface 30), the light to be imaged enters the imaging unit 4 (specifically, lower plate 4a) from the direction indicated by arrow A1 in FIG.

[0129] The light to be imaged that is incident on the lower plate 4a is first reflected by the light reflecting portion 42 of the lower plate 4a. The light reflected by the light reflecting portion 42 of the lower plate 4a (i.e., the first reflected light) is incident on the upper plate 4b.

[0130] The first reflected light incident on upper plate 4b is reflected by light reflecting portion 42 of upper plate 4b and emitted from the upper surface (in other words, the second surface) of upper plate 4b (in other words, imaging unit 4). The light emitted from upper plate 4b (in other words, imaging unit 4) is imaged on imaging plane S as aerial image G1.

[0131] It is desirable that the aerial image G1 formed by the imaging unit 4 be of high image quality. However, the inventors of the present invention have found that with conventionally manufactured imaging units, the image quality of the aerial image may be degraded due to the manufacturing method of the imaging unit.

[0132] Specifically, the inventors of the present invention have discovered that in the case of the conventional manufacturing method of the imaging unit, in the process of bonding the lower plate 4a and the upper plate 4b together, deformation (specifically, warping) of the protrusions 43 on the lower plate 4a and the upper plate 4b may occur due to the hardening shrinkage of the adhesive.

[0133] More specifically, the inventors of the present invention have found that deformation (specifically, warping) may occur in vertical surfaces 431 of protrusions 43 on lower plate 4a and upper plate 4b, as indicated by two-dot chain line β in Figure 5. Such deformation of protrusions 43 adversely affects the reflection of the target light by light reflecting portion 42. As a result, the image quality of aerial image G1 formed on imaging surface S deteriorates.

[0134] Therefore, as a result of extensive efforts, the inventors of the present invention have invented a method for manufacturing the imaging unit 4 (in other words, a method for manufacturing an optical plate) that can suppress deformation (specifically, warpage) of the protrusions 43 of the lower plate 4a and the upper plate 4b. The method for manufacturing the optical plate according to the present invention will be described below.

[0135] (Method of manufacturing optical plates) Fig. 7 is a flowchart showing steps of a method for manufacturing an optical plate.Figs. 8a to 8f are schematic diagrams showing steps of a method for manufacturing an optical plate.

[0136] In the following description, the entity that performs the optical plate manufacturing method is mainly an operator. However, the entity that performs the optical plate manufacturing method is not limited to an operator. For example, the entity that performs the optical plate manufacturing method may be a manufacturing device.

[0137] (Step S101) In step S101 of FIG. 7, as shown in FIG. 8a, an operator applies adhesive 71 to a first surface (in other words, a first main surface) of the lower plate 4a to obtain a first intermediate body 81. The type of adhesive 71 is as described above. The process performed in step S101 is referred to as an adhesive application process. The adhesive application process may be performed at room temperature.

[0138] The worker may apply a resin sealant to the outer edge of the first surface of the lower plate 4a before applying the adhesive 71 to the first surface of the lower plate 4a. The sealant functions as a dam that prevents the adhesive 71 from flowing out from the first surface of the lower plate 4a.

[0139] The sealant may be, for example, a light-curing (specifically, ultraviolet-curing) sealant. After applying the sealant to the first surface of the lower plate 4a, the worker may irradiate the sealant with light (specifically, ultraviolet light) to cure the sealant.

[0140] (Step S102) 7, the worker places the upper plate 4b on the lower plate 4a of the first intermediate body 81 to which the adhesive 71 has been applied, thereby obtaining the second intermediate body 82 shown in FIG. 8b. The process performed in step S102 is referred to as a plate superposition process. The plate superposition process may be performed at room temperature.

[0141] The adhesive 71 is not yet hardened in the second intermediate body 82. Therefore, in the second intermediate body 82, the lower plate 4a and the upper plate 4b are not fixed to each other.

[0142] (Step S103) In step S103 of FIG. 7, the worker bonds the lower plate 4a and the upper plate 4b of the second intermediate body 82 together to obtain a third intermediate body 83 shown in FIG. 8c. The third intermediate body 83 corresponds to an example of an intermediate plate body. The process performed in step S103 is called a plate bonding process. The plate bonding process may be performed at room temperature. The plate bonding process corresponds to an example of a process for obtaining an intermediate plate body.

[0143] 7, the worker uses a bonding device to bond the lower plate 4a and the upper plate 4b together. The bonding device is, for example, a vacuum bonding device.

[0144] 7, the worker places the second intermediate body 82 in the accommodation chamber 911 of the vacuum laminating device 91. Then, the worker operates the vacuum laminating device 91 to perform vacuum lamination on the second intermediate body 82.

[0145] Here, a brief description will be given of the configuration of the third intermediate 83 obtained in step S103. The third intermediate 83 has a lower plate 4a, an upper plate 4b, and an adhesive 71. The adhesive 71 is provided between a first surface (upper surface in FIG. 8b) of the lower plate 4a and a first surface (lower surface in FIG. 8b) of the upper plate 4b.

[0146] The adhesive 71 is not cured in the third intermediate 83. Therefore, the lower plate 4a and the upper plate 4b are not fixed to each other in the third intermediate 83. In the present embodiment, a plate bonding step for obtaining the third intermediate 83 is performed before the partial curing step in step S104 described below.

[0147] (Step S104) In step S104 of FIG. 7, an operator irradiates the third intermediate 83 with ultraviolet light UV using an ultraviolet irradiation device 90 to partially cure the adhesive 71 in the third intermediate 83. As a result, a fourth intermediate 84 shown in FIG. 8d is obtained. The process performed in step S104 is referred to as a partial curing process. The partial curing process is performed in an environment of 50°C or less.

[0148] In this embodiment, since the adhesive 71 is an ultraviolet-curable adhesive, in step S104, ultraviolet rays are irradiated onto the adhesive 71 to partially cure the adhesive 71. In step S104, the method for partially curing the adhesive 71 may be determined depending on the type of adhesive 71.

[0149] The reactivity of the adhesive 71 cured in step S104 may be determined depending on the type of adhesive, since it affects the collapse in step S105. For example, the reactivity of the adhesive 71 cured in step S104 may be 10% or more and 60% or less. The reactivity of the adhesive 71 cured in step S104 may preferably be 20% or more and 40% or less of the adhesive 71. The reactivity of the adhesive can be calculated based on the ratio of a base peak to a functional group peak measured by infrared absorption analysis before and after UV irradiation. More specifically, the reactivity of the adhesive can be calculated from the rate of decrease in the ratio of the functional group peak to the base peak measured by infrared absorption analysis before and after UV irradiation. For example, the reactivity of the adhesive before curing is 0%, and the reactivity of the adhesive after complete curing is 100%. Here, the base peak refers to a peak derived from a structure that does not change during the curing reaction (i.e., is not involved in the curing reaction), and the functional group peak refers to a peak derived from a functional group that is consumed during the curing reaction (i.e., is involved in the curing reaction).

[0150] In step S104, no force other than the force based on gravity is acting on the third intermediate 83. In other words, in step S104, the third intermediate 83 is not pressed in the thickness direction of the third intermediate 83 (the up-and-down direction in FIG. 8d). That is, in step S104, the worker partially hardens the adhesive 71 without pressing the third intermediate 83, thereby obtaining the fourth intermediate 84.

[0151] (Step S105) 7, the worker assembles the fourth intermediate body 84 to the press die 921 of the press device 92. The press die 921 has a lower die 921a and an upper die 921b. As shown in FIG. 8e, the worker places the fourth intermediate body 84 between the lower mold 921a and the upper mold 921b.

[0152] Then, while pressing the fourth intermediate 84 in the thickness direction, the worker irradiates the fourth intermediate 84 with ultraviolet light UV using the ultraviolet irradiation device 90, thereby curing the adhesive 71 in the fourth intermediate 84 entirely. As a result, a fifth intermediate 85 shown in FIG. 8f is obtained. The process performed in step S105 is referred to as a final curing process. The final curing process is performed in an environment of 50°C or less.

[0153] In this embodiment, since the adhesive 71 is an ultraviolet-curable adhesive, in step S105, the adhesive 71 is irradiated with ultraviolet light UV to completely cure the adhesive 71. In step S105, the method for partially curing the adhesive 71 may be determined depending on the type of adhesive 71.

[0154] Thereafter, the worker performs post-processing on the fifth intermediate 85 to obtain the imaging unit 4 (in other words, the optical plate). The post-processing may include, for example, a process of heating the fifth intermediate 85 (also referred to as a heat treatment). The heat treatment may be omitted. In this case, the fifth intermediate 85 corresponds to the imaging unit 4.

[0155] (Actions and Effects of This Embodiment) According to the method for manufacturing an optical plate according to this embodiment as described above, it is possible to realize an optical plate (in other words, imaging unit 4) that can form a high-quality aerial image. The reason for this will be explained below.

[0156] As described above, the inventors of the present invention have discovered that in the conventional manufacturing method of optical plates, deformation (specifically, warping) of the protrusions 43 of the lower plate 4a and the upper plate 4b may occur due to the hardening shrinkage of the adhesive.

[0157] Furthermore, as a result of further deepening their knowledge, the inventors of the present invention have discovered that a large cure shrinkage rate of the adhesive is one of the causes of deformation (specifically, warpage) of the protrusions 43. The cure shrinkage rate of the adhesive is the ratio of the change in volume of the adhesive before and after curing.

[0158] In order to solve this problem, the inventors of the present invention have come to the realization through ingenuity that if the adhesive 71 is cured in two stages, the cure shrinkage rate of the adhesive 71 can be reduced compared to when the adhesive 71 is cured all at once.

[0159] Based on this knowledge, the inventor of the present invention came up with a method for manufacturing an optical plate according to this embodiment, in which the process of curing adhesive 71 is divided into a partial curing process in which adhesive 71 is partially cured, and a final curing process in which adhesive 71 is cured entirely.

[0160] In particular, in the method for manufacturing an optical plate according to this embodiment, in the partial curing step of partially curing the adhesive 71, the second intermediate 82 is irradiated with ultraviolet light without being pressed in the thickness direction, thereby partially curing the adhesive 71. In other words, the lower plate 4a and the upper plate 4b are not pressed against the adhesive 71 in the partial curing step.

[0161] By performing such a partial curing step before the final curing step, it is possible to further reduce the cure shrinkage rate of the adhesive 71. As a result, deformation (specifically, warpage) of the protrusions 43 on the lower plate 4a and the upper plate 4b is effectively suppressed.

[0162] This results in reduced degradation in the quality of the aerial image formed by the imaging unit 4. Therefore, the method for manufacturing an optical plate according to this embodiment makes it possible to achieve an imaging unit 4 that can form a high-quality aerial image.

[0163] [Embodiment 2] Next, a method for manufacturing an optical plate according to the second embodiment of the present invention will be described with reference to FIG. 9 and FIGS. 10a to 10f.

[0164] The configuration of the imaging unit 4 manufactured by the optical plate manufacturing method according to this embodiment is the same as the configuration of the imaging unit 4 in the above-mentioned embodiment 1. Therefore, with regard to the configuration of the imaging unit 4, the description of the configuration of the imaging unit 4 in the above-mentioned embodiment 1 may be appropriately cited.

[0165] In the method for manufacturing an optical plate according to this embodiment, the timing of performing the partial curing step of partially curing the adhesive 71 is different from the method for manufacturing an optical plate according to the first embodiment described above.

[0166] (Step S201) First, in step S201 of Fig. 9, as shown in Fig. 10a, an operator applies adhesive 71 to a first surface (in other words, a first main surface) of the lower plate 4a to obtain a first intermediate body 81. The process performed in step S201 is referred to as an adhesive application process, similar to the process performed in step S101 of Fig. 7.

[0167] (Step S202) 9, the worker irradiates the first intermediate 81 with ultraviolet light UV using the ultraviolet irradiation device 90 to partially cure the adhesive 71 in the first intermediate 81. Then, a second intermediate 82B shown in FIG. 10b is obtained. The process performed in step S202 is referred to as a partial curing process, similar to the process performed in step S104 in FIG. 7.

[0168] As described above, in the method for manufacturing an optical plate according to this embodiment, the timing at which the partial curing step is performed is different from the timing at which the partial curing step is performed in the first embodiment described above.

[0169] (Step S203) 9, the worker overlaps the upper plate 4b on the lower plate 4a of the second intermediate 82B to which the adhesive 71 has been applied, as shown in FIG. 10c, to obtain a third intermediate 83B. The process performed in step S202 is referred to as a plate overlapping process, similar to the process performed in step S102 of FIG. 7 described above.

[0170] (Step S204) Next, in step S204 of Fig. 9, the worker bonds the lower plate 4a and the upper plate 4b of the third intermediate body 83B together to obtain a fourth intermediate body 84B shown in Fig. 10d. The fourth intermediate body 84B corresponds to an example of an intermediate plate body.

[0171] The process performed in step S204 is referred to as a plate bonding process, similar to the process performed in step S103 of FIG. 7 described above. In step S204 of FIG. 9, an operator uses a bonding device (specifically, a vacuum bonding device 91) to bond the lower plate 4a and the upper plate 4b together. In this embodiment, after the partial curing process, the plate bonding process is performed to obtain an intermediate plate body. The plate bonding process corresponds to an example of a process for obtaining an intermediate plate body.

[0172] (Step S205) 9, the worker assembles the fourth intermediate body 84B to the press die 921 of the press device 92. Specifically, as shown in FIG. 10e, the worker places the fourth intermediate body 84 between the lower die 921a and the upper die 921b.

[0173] Then, while pressing the fourth intermediate 84B in the thickness direction, the worker irradiates the fourth intermediate 84B with ultraviolet light UV using the ultraviolet irradiation device 90 to cure the adhesive 71 on the fourth intermediate 84B entirely, thereby obtaining a fifth intermediate 85 shown in FIG. 10f.

[0174] The fifth intermediate 85 shown in Fig. 10f is the same as the fifth intermediate 85 shown in Fig. 8f. The process performed in step S205 is referred to as a final curing process, similar to the process performed in step S105 in Fig. 7.

[0175] Thereafter, the worker performs post-processing on the fifth intermediate 85 to obtain the imaging unit 4 (in other words, the optical plate). The post-processing is, for example, a process of heating the fifth intermediate 85 (also referred to as a heat treatment). The heat treatment may be omitted. In that case, the fifth intermediate 85 corresponds to the imaging unit 4. The other configurations, functions, and effects of the method for manufacturing an optical plate are the same as those of the method for manufacturing an optical plate in the first embodiment described above. [Industrial Applicability]

[0176] The present invention can be applied to a method for manufacturing an imaging portion in an aerial imaging device used for various purposes. [Explanation of symbols]

[0177] 1. Non-contact input device 2. Case 21 Support part 3 Display section 30 Display surface 31 Main body 4 Imaging section 4a Lower plate 4b Upper plate 4c adhesive layer 41 Main body 42 Light reflecting part 43 protrusion 431 Vertical plane 432 Slope 44 Groove 5 Input detection section 6 Control Unit 71 Adhesive 81 First intermediate 82, 82B Second intermediate 83, 83B Third intermediate 84, 84B Fourth intermediate 85 Fifth intermediate 90 Ultraviolet irradiation device 91 Vacuum lamination equipment 911 Containment Room 92 Press equipment 921 Press mold 921a lower mold 921b upper mold G1 Aerial Image U User S image plane UV ultraviolet light

Claims

1. a first plate having a plurality of ridges on a first main surface; a second plate having a plurality of ridges on a second main surface; an adhesive layer provided between the first main surface and the second main surface, applying an adhesive to a first major surface of the first plate; partially curing the adhesive; a step of forming the adhesive layer by entirely curing the adhesive while pressing an intermediate plate body in which the second plate is placed on the adhesive; Including, A method for manufacturing optical plates.

2. the adhesive is a photocurable adhesive, In the step of partially curing the adhesive, ultraviolet light is irradiated onto the adhesive to partially cure the adhesive, In the step of totally curing the adhesive, ultraviolet light is irradiated onto the adhesive to totally cure the adhesive. A method for manufacturing the optical plate according to claim 1 .

3. The cure shrinkage rate of the adhesive is 5% or less. A method for manufacturing the optical plate according to claim 1 .

4. obtaining the intermediate plate body before the step of partially curing the adhesive; In the step of partially curing the adhesive, the adhesive is partially cured without pressing the intermediate plate body. A method for manufacturing the optical plate according to claim 1 .

5. obtaining the intermediate plate body after the step of partially curing the adhesive; A method for manufacturing the optical plate according to claim 1 .

Images