Patent Description:
Conventionally, in optical devices such as liquid crystal display devices used in information terminals such as smartphones or car navigation devices, a light-transmissive cured resin layer is provided between an optical member such as a liquid crystal display panel and a transparent panel for protecting the optical member for the purpose of thinning the device and improving visibility.

For example, a method for forming the cured resin layer includes: applying a photocurable resin composition to a transparent panel to form a curable resin layer; laminating an optical member such as a liquid crystal display panel or an organic EL panel through the curable resin layer; and then curing the curable resin layer (Patent Document <NUM>).

As a method for applying the photocurable resin composition to the transparent panel, there have been used a method in which the photocurable resin composition is discharged from a moving slit nozzle over the entire width to the surface of the transparent panel and a method in which the photocurable resin composition is applied by screen printing, among other methods.

Further, <CIT> discloses a display device comprising a display panel having an active area to display an image; a transparent front plate disposed in front of the display panel; and a transparent resin layer in a gel state, the resin layer formed between the front plate and the active area. <CIT> discloses a manufacturing method for a transparent surface material equipped with an adhesive layer, whereby air bubbles at the interface between the adhesive layer and an object to which the layer is to be adhered dissipate quickly. <CIT> discloses a method for producing a bonded plate-shaped assembly, comprising the steps of retaining pair plate-shaped members facing each other by pair retaining base members; charging a photo-curable liquid material between the pair plate-shaped members facing each other; causing movement of the pair retaining base members by a retaining base member movement unit to cause the pair plate-shaped members to draw close to each other to cause wetting spreading of the liquid material between the plate-shaped members; detecting the wetting spreading state of the liquid material by a sensor; illuminating curing light, in response to the result of detection, to the liquid material wettingly spread to the entire surfaces of the pair plate-shaped members, to form the bonded plate-shaped assembly made up of the pair plate-shaped members bonded together. <CIT> discloses methods for optically cohering substrates together. <CIT> describes an image in which an image display member such as a liquid crystal display panel and a light transmissive cover member such as a curved transparent protective sheet arranged on the surface side of the image display member are laminated via a light transmissive cured resin layer, as well as a method of manufacturing the display device.

However, in the conventional manufacturing method described above, when the optical member and the transparent panel become large in size, there arise problems in which a large vacuum laminating device is required for bonding and a large autoclave is required after bonding.

Further, in the photocurable resin composition applied on a light shielding portion provided on the transparent panel, since the curing light irradiated from the surface side of the transparent panel is shielded by the light shielding portion to inhibit the curing, so-called side curing is performed by irradiating curing light from the side surface of the transparent panel.

In recent years, there has been proposed an optical device in which a plurality of optical members are arranged close to each other and one transparent panel is laminated. As shown in <FIG>, in such an optical device <NUM>, light shielding portions <NUM> respectively corresponding to optical members 52a, 52b are formed adjacently on a transparent panel <NUM>. The side curing is possible in three sides of each light shielding portion <NUM> facing the side surface of the transparent panel <NUM>; however, the side curing is difficult in the portion where the optical members 52a, 52b are adjacent to each other.

In view of the above, it is an object of the present technology to provide an optical device which does not require a large vacuum laminating device, an autoclave process, or a side curing step even in a large optical device, and a method for manufacturing the optical device. Another object of the present technology is to provide a method for manufacturing an optical device, in which a plurality of optical members are arranged in close proximity, capable of reliably curing a photocurable resin composition.

In order to solve the problems described above, an aspect of the present invention provides a method for manufacturing an optical device in which an optical member and a transparent panel are bonded together via a cured resin layer, including: a step of forming, on one of the optical member and the transparent panel, a wall surrounding a forming region for the cured resin layer and having at least one opening; a step of laminating the optical member and the transparent panel to form a laminated body in which a resin filling space surrounded by the wall is formed between the optical member and the transparent panel; a step of filling the resin filling space of the laminated body with a photocurable resin composition; and a step of curing the photocurable resin composition to form the cured resin layer, wherein the opening of the wall is provided with a projecting portion extending outside the resin filling space and surrounded by the wall.

In addition, an optical device according to the present technology includes: an optical member; a transparent panel bonded to the optical member; and a cured resin layer interposed between the optical member and the transparent panel, wherein, on the transparent panel, a light shielding portion is formed in a region corresponding to the peripheral edge of a display region of the optical member, wherein, on the display region side of the light shielding portion, a wall defining a forming region for the cured resin layer is formed, and wherein the wall portion has an opening provided therein and the opening is provided with a projecting portion surrounded by the wall and extending outside the region where the cured resin layer is formed.

Further, an optical device according to the present technology includes: a plurality of optical members; one transparent panel bonded to the plurality of optical members; and a cured resin layer interposed between the plurality of optical members and the transparent panel, wherein, on the transparent panel, a light shielding portion is formed in a region corresponding to the peripheral edge of a display region of the optical member, wherein, on the display region side of the light shielding portion, a wall defining a filling region for the cured resin layer is formed, and wherein the wall portion has an opening provided therein and the opening is provided with a projecting portion surrounded by the wall and extending outside the region where the cured resin layer is formed.

According to the present technology, since the photocurable resin composition is injected and cured in the resin filling space defined by the wall, a large vacuum laminating device, an autoclave step and a side curing step are not required.

Hereinafter, an optical device and a method for manufacturing the optical device according to the present technology will be described in detail with reference to the drawings. Moreover, the features illustrated in the drawings are shown schematically and are not intended to be drawn to scale. Actual dimensions should be determined in consideration of the following description. Furthermore, those skilled in the art will appreciate that dimensional relations and proportions may be different among the drawings in certain parts.

The present technology provides an optical device <NUM> formed by bonding an optical member <NUM> and a transparent panel <NUM> through a cured resin layer <NUM>, and a method for manufacturing an optical device <NUM>. Prior to the description of the method for bonding the transparent panel <NUM> and the optical member <NUM>, the configuration of the optical device <NUM> will be described.

The optical device <NUM> is an optical device such as a liquid crystal display panel and an organic EL display panel, among others, and is used in various information terminals and information devices such as a smartphone, a car navigation device, an instrument panel, and the like. As shown in <FIG> and <FIG>, the optical device <NUM> is provided with a light-transmissive cured resin layer <NUM> between the optical member <NUM> such as a liquid crystal display panel and the transparent panel <NUM> for protecting the optical member <NUM> for the purpose of thinning the device and improving visibility.

The optical device <NUM> includes a single-panel optical device 1A in which one optical member <NUM> and one transparent panel <NUM> are laminated via the cured resin layer <NUM> as shown in <FIG>, and a multi-panel optical device 1B in which a plurality of optical members <NUM> and one transparent panel <NUM> are laminated via the cured resin layer <NUM> as shown in <FIG>. The multi-panel optical device 1B is formed by bonding the plurality of optical members <NUM> to the transparent panel <NUM>, and in the example shown in <FIG>, the two optical members 2A, 2B are arranged side by side.

The transparent panel <NUM> has light transmissive property and is laminated with the optical member <NUM> through the cured resin layer <NUM> to cover and protect the display surface of the optical member <NUM> while ensuring the visibility of the optical member <NUM>.

The transparent panel <NUM> may be made of glass or a resin material such as acrylic resin, polyethylene terephthalate, polyethylene naphthalate, or polycarbonate, as long as the transparent panel <NUM> is optically transparent so that an image formed on the optical member is visible. These materials can be subjected to a single-side or double-side hard coat treatment, antireflection treatment, or the like. When the optical member <NUM> described later is a touch panel, a part of the member of the touch panel can be used as the transparent panel <NUM>.

On the transparent panel <NUM>, in order to improve the brightness and contrast of the display image, a black frame-shaped light shielding portion <NUM> called a black matrix is formed in a region corresponding to the peripheral edge of the display region of the optical member <NUM>. In the optical device <NUM>, the inside of the light shielding portion <NUM> surrounding the display region of the optical member <NUM> functions as a display portion <NUM> for transmitting an image displayed on the display region of the optical member <NUM> through the transparent panel <NUM>.

The light shielding portion <NUM> is formed to have a uniform thickness by applying a coating material colored in black or the like by a screen printing method or the like, and then drying and curing the coating material. The thickness of the light shielding portion <NUM> is usually <NUM> to <NUM>. As shown in <FIG>, the transparent panel <NUM> of the multi-panel optical device 1B is provided with a plurality of display portions <NUM> by forming frame-shaped light shielding portions <NUM> in accordance with the optical members 2A and 2B.

The shape of the transparent panel <NUM> is not particularly limited, and may be, for example, a flat shape, a shape curved in one direction, a rotated paraboloid, a hyperbolic paraboloid, or another quadric surface, or may have a flat portion in a part of a curved shape and a quadric surface shape.

It should be noted that the dimensional characteristics such as the shape of the curvature and thickness and physical properties such as elasticity of the cover member can be appropriately determined according to the intended use of the optical device <NUM>.

Examples of the optical member <NUM> includes image display members such as a liquid crystal display panel, an organic EL display panel, a plasma display panel, and a touch panel. Here, the touch panel means an image display/input panel which combines a display element such as a liquid crystal display panel and a position input device such as a touch pad. The surface shape of the optical member <NUM> on the side of the transparent panel <NUM> is not particularly limited, but is preferably flat. Moreover, a polarizing plate may be arranged on the surface of the optical member <NUM>.

In the optical device <NUM> according to the present technology, a wall <NUM> is formed on a bonding surface of one of the optical member <NUM> and the transparent panel <NUM> to define a forming region for a cured resin layer <NUM> to be described later. As shown in <FIG>, the wall portion <NUM> has an opening <NUM> provided therein and the opening <NUM> is provided with a projecting portion 13a extending outside the region where the cured resin layer <NUM> is formed. The wall <NUM> defines a filling region for a photocurable resin composition <NUM> constituting the cured resin layer <NUM>, and prevents the photocurable resin composition <NUM> from protruding outward from the wall <NUM>. The wall <NUM> is formed substantially in a frame shape along the light shielding portion <NUM> on the display region side of the light shielding portion <NUM> formed in a frame shape. Thus, the wall <NUM> is provided in contact with the inside of the light shielding portion <NUM>. The wall <NUM> may be formed from the upper surface of the light shielding portion <NUM> to the display region side surrounded by the light shielding portion <NUM>.

Further, although the wall <NUM> may be formed on the optical member <NUM> or the transparent panel <NUM>, it is generally preferably formed on the optical member <NUM> side having a flat display region since it is preferably formed on a flat surface so as to have a substantially uniform thickness over the entire length. It is needless to say that the wall <NUM> may be formed on the transparent panel <NUM>. By bonding the optical member <NUM> and the transparent panel <NUM>, the wall <NUM> defines, together with the optical member <NUM> and the transparent panel <NUM>, a filling space to be filled with the photocurable resin composition <NUM>. The wall <NUM> has elasticity and high adhesiveness as described later, thereby preventing the liquid leakage of the injected photocurable resin composition <NUM> by being closely contact with the transparent panel <NUM> or the optical member <NUM> to be bonded.

In addition, the wall <NUM> is preferably formed of the same resin composition as that of the cured resin layer <NUM> described later. Since the wall <NUM> is formed inside the light shielding portion <NUM> to be formed on the display portion <NUM> of the optical device <NUM> which transmits an image displayed on the display region of the optical member <NUM>, the wall <NUM> preferably has light transmissive property similar to the cured resin layer <NUM>. Further, it is in contact with the cured resin layer <NUM> in the display portion <NUM>, the interface with the cured resin layer <NUM> does not visible and display properties are not impaired by forming them with the same resin composition.

The height of the wall <NUM> can be appropriately set in accordance with the thickness of the cured resin layer <NUM> to be formed, and as an example, it is formed to be <NUM> to <NUM> in a state of being sandwiched between the optical member <NUM> and the transparent panel <NUM>. The step of forming such a wall <NUM> and the step of forming a filling space for the photocurable resin composition will be described later in detail.

The cured resin layer <NUM> interposed between the transparent panel <NUM> and the optical member <NUM> has a light transmissive property so that the image displayed by the optical member <NUM> such as an image display member is visible.

The photocurable resin composition <NUM> constituting the cured resin layer <NUM> is liquid, and specifically exhibits a viscosity of <NUM> to <NUM> Pa*s (<NUM>) with a cone plate type viscometer, for example.

The photocurable resin composition <NUM> preferably contains a base component (component (a)), an acrylic monomer component (component (b)), a plasticizer component (component (c)) and a photopolymerization initiator (component (d)).

The base component (a) is a film-forming component of the light-transmissive cured resin layer <NUM> and contains at least one of an elastomer and an acrylic oligomer. Both may be used in combination as the component (a).

Examples of elastomers include acrylic copolymer consisting of acrylic ester, polybutene, and polyolefin, among others. The weight average molecular weight of the acrylic ester copolymer is preferably <NUM>,<NUM> to <NUM>,<NUM>, and the number of repetitions n of polybutene is preferably <NUM> to <NUM>,<NUM>.

Preferred examples of acrylic oligomers include (meth) acrylate oligomers having a backbone of polyisoprene, polyurethane or polybutadiene, among others. In the present specification, the term "(meth) acrylate" includes acrylate and methacrylate.

Preferred examples of (meth) acrylate oligomers having a polyisoprene backbone include esterified product of maleic anhydride adduct of polyisoprene polymer and <NUM>-hydroxyethyl methacrylate UC102 (KURARAY) (molecular weight in terms of polystyrene: <NUM>,<NUM>), UC203 (KURARAY) (molecular weight in terms of polystyrene: <NUM>,<NUM>), and UC-<NUM> (KURARAY) (molecular weight about <NUM>,<NUM>).

Preferred examples of the (meth) acrylic-type oligomers having a polyurethane backbone include aliphatic urethane acrylate (EBECRYL <NUM> (Daicel-Cytec) (molecular weight of <NUM>,<NUM>) and UA-<NUM> (Light Chemical)), among others.

For (meth) acrylate oligomer, known (meth) acrylate oligomer having a polybutadiene backbone may be employed.

The acrylic monomer component (b) is used as a reactive diluent in order to impart sufficient reactivity and coatability to the photocurable resin composition in the manufacturing step of the optical device. Examples of such acrylic monomers include <NUM>-hydroxypropyl methacrylate, benzyl acrylate, and dicyclopentenyloxyethyl methacrylate, among others.

It should be noted that the total content of the base component (a) and the acrylic monomer component (b) in the photocurable resin composition <NUM> is preferably <NUM> to <NUM>% by mass.

The plasticizer component (c) is used to impart a buffer property to the cured resin layer and to reduce the cure shrinkage of the photocurable resin composition, and does not react with the acrylate oligomer component of a component (a) and the acrylic monomer component of a component (b) during irradiation of an ultraviolet-ray. Such plasticizer components contain a solid tackifier (<NUM>) and a liquid oil component (<NUM>).

Examples of the solid tackifier (<NUM>) include: terpene-based resins such as terpene resin, terpene phenol resin, and hydrogenated terpene resin; rosin-based resins such as natural rosin, polymerized rosin, rosin ester, and hydrogenated rosin; and terpene-based hydrogenated resins, among others. In addition, non-reactive oligomers obtained by low molecular weight polymerizing the above-mentioned acrylic monomers in advance can also be used; specifically, copolymers of butyl acrylate and <NUM>-hexyl acrylate and acrylic acid, or copolymers of cyclohexyl acrylate and methacrylic acid can be used.

The liquid oil component (<NUM>) may contain a polybutadiene type oil or a polyisoprene type oil.

The content of the plasticizer component (c) in the photocurable resin composition <NUM> is preferably <NUM> to <NUM>% by mass.

As the photopolymerization initiator designated as the component (d), known photo radical polymerization initiators can be used, which include <NUM>-hydroxy-cyclohexyl phenyl ketone (IRGACURE <NUM>, BASF), <NUM>-hydroxy-<NUM>- {<NUM>- [<NUM>- (<NUM>-hydroxy-<NUM>-methyl-propionyl) benzyl] phenyl} -<NUM>-methyl-<NUM>-propan-<NUM>-one (IRGACURE <NUM>, BASF), benzophenone, and acetophenone, among others.

Insufficient amount of such a photopolymerization initiator relative to <NUM> parts by mass in total of the base component (a) and the acrylic monomer component (b) result in insufficient curing at the time of ultraviolet irradiation and excessive amount tends to cause problems of foaming since cleavage will increase outgassing; the amount, therefore, is preferably <NUM> to <NUM> parts by mass, and more preferably <NUM> to <NUM> parts by mass.

The photocurable resin composition <NUM> can also contain a chain transfer agent for the purpose of adjusting the molecular weight. For example, <NUM>-mercaptoethanol, lauryl mercaptan, glycidyl mercaptan, mercaptoacetic acid, <NUM>-ethylhexyl thioglycolate, <NUM>,<NUM>-dimethyl capto-<NUM>-propanol, and α-methylstyrene dimer may be used.

The photocurable resin composition <NUM> may further contain, if necessary, general additives including an adhesion improver such as a silane coupling agent and an antioxidant. Further, with regard to the components (a) to (d) of the photocurable resin composition, the components (a) may not be used if appropriate components (b) and (c) are employed.

Next, a first manufacturing step of the optical device <NUM> will be described with reference to a manufacturing method for the multi-panel optical device 1B shown in <FIG>. The first step of manufacturing the optical device <NUM> includes: a step (A) of forming, on one of the optical member <NUM> and the transparent panel <NUM>, a wall <NUM> made of a first curable resin composition <NUM> surrounding the forming region of the cured resin layer <NUM> and having at least one opening <NUM>; a step (B) of laminating the optical member <NUM> and the transparent panel <NUM> to form a laminated body <NUM> in which a resin filling space <NUM> surrounded by the wall <NUM> is formed between the optical member <NUM> and the transparent panel <NUM>; a step (C) of injecting the photocurable resin composition <NUM> from the opening <NUM> of the laminated body <NUM>; and a step (D) of curing the photocurable resin composition <NUM> to form the cured resin layer <NUM>.

First, two optical members <NUM> and one transparent panel <NUM> are prepared. As described above, the transparent panel <NUM> has the light shielding portion <NUM> formed on one surface to which the optical member <NUM> is bonded. The light shielding portion <NUM> is formed so as to surround each display region of the two optical members <NUM> to be positioned adjacently, and forms two rectangular frames sharing one side.

Each of the optical member <NUM> is formed with the wall <NUM> made of the first curable resin composition <NUM>, which surrounds the forming region where the cured resin layer <NUM> is to be formed and is provided with at least one opening <NUM>.

As shown in <FIG>, the wall <NUM> is formed by applying and curing the first curable resin composition <NUM> in a predetermined shape. The wall <NUM> is formed so as to abut the transparent panel <NUM>, when bonded, from the upper surface to the inside of the light shielding portion <NUM>, and as shown in <FIG>, for example, is formed in a substantially frame shape in accordance with the light shielding portion <NUM> formed in a frame shape.

The first curable resin composition <NUM> is applied in a substantially frame shape by a dispenser, for example, as shown in <FIG>. When a photocurable resin composition is used as the first curable resin composition <NUM>, the first curable resin composition <NUM> is cured by irradiation with curing light after the application. In addition, as the first curable resin composition <NUM>, a known resin supplying method such as printing may be used.

The cured wall <NUM> has elasticity and high adhesiveness, and when pressed against the transparent panel <NUM> later, it is deformed into a shape having a substantially trapezoidal cross section, bulges toward the upper surface of the light shielding portion <NUM> of the transparent panel <NUM> and the display region side of the optical member <NUM>, and is in close contact with the upper surface of the light shielding portion <NUM> of the transparent panel <NUM> and the display region side of the optical member <NUM>. Thus, the wall <NUM> forms the resin filling space <NUM> to be filled with the photocurable resin composition <NUM> between the optical member <NUM> and the transparent panel <NUM>, and liquid leakage of the photocurable resin composition <NUM> is prevented. It should be noted that the application height of the first curable resin composition <NUM> is determined by adding, to the thickness of the bonding with the transparent panel <NUM>, an thickness bulging toward the upper surface of the light shielding portion <NUM> and the display region side of the optical member <NUM> due to the deforming of the wall <NUM>.

As shown in <FIG>, the substantially frame-shaped wall <NUM> has at least one opening <NUM>. The opening <NUM> functions as an injection hole for injecting the photocurable resin composition <NUM> into the resin filling space <NUM>, and also functions as an exhaust hole for exhausting air from the resin filling space <NUM>. The opening <NUM> has an opening diameter sufficient for inserting an injection nozzle <NUM> (see <FIG>) to inject the photocurable resin composition <NUM> and exhausting air from the resin filling space <NUM>. Although the opening <NUM> may be formed at any position of the wall <NUM>, by forming it near a corner, the photocurable resin composition <NUM> can be injected with the opening <NUM> facing upward, and the exhaust of air in the resin filling space <NUM> is prevented from being inhibited by the wall <NUM>, so that the resin filling space <NUM> can be surely filled with the photocurable resin composition <NUM>.

Next, as shown in <FIG>, the optical member <NUM> and the transparent panel <NUM> are bonded to each other to form the laminated body <NUM> in which the resin filling space <NUM> surrounded by the wall <NUM> is formed between the optical member <NUM> and the transparent panel <NUM>. <FIG> is an upper cross-sectional view illustrating the laminated body <NUM>. The transparent panel <NUM> and the optical member <NUM> are supported by fixing plates <NUM> provided on the rear surface opposite to the bonding surface. The laminated body <NUM> is formed by arranging the transparent panel <NUM> and the optical member <NUM> so that the light shielding portion <NUM> and the wall <NUM> each formed in a frame shape faces each other, and sandwiching them by the fixing plates <NUM>.

As described above, the wall <NUM> has elasticity and high adhesiveness, and when pressed against the transparent panel <NUM> via the fixing plate <NUM>, the wall <NUM> is deformed into a shape having a substantially trapezoidal cross section, and brought in close contact with the upper surface and the inside of the light shielding portion <NUM> of the transparent panel <NUM>. As a result, in the laminated body <NUM>, the optical member <NUM>, the transparent panel <NUM>, and the wall <NUM> form the resin filling space <NUM> to be filled with the photocurable resin composition <NUM>, and the photocurable resin composition <NUM> can be injected into the resin filling space <NUM> from the opening <NUM> provided in the wall <NUM>. Further, in the resin filling space <NUM>, close contact of the wall <NUM> with the transparent panel <NUM> can prevent the liquid leakage of the photocurable resin composition <NUM>.

Next, as shown in <FIG>, an injection nozzle <NUM> is inserted from the opening <NUM> of the resin filling space <NUM>, and the resin filling space <NUM> is filled with the photocurable resin composition <NUM>. At this time, by injecting the photocurable resin composition <NUM> with the opening <NUM> facing upward, the air in the resin filling space <NUM> is exhausted from the opening <NUM>, and the occurrence of voids can be prevented.

In addition, as shown in <FIG>, the filling step of the photocurable resin composition <NUM> is preferably carried out by tilting the laminated body <NUM> so that the opening <NUM> is positioned at the uppermost position in the vertical direction. Thus, the air in the resin filling space <NUM> flows toward the opening <NUM>, thereby preventing the air from remaining as voids in the corners of the resin filling space <NUM> or the like.

Although the injection nozzle <NUM> can inject the photocurable resin composition <NUM> as long as the tip is inserted into the opening <NUM>, the photocurable resin composition <NUM> can be injected at a high speed while preventing the entrainment of air by dipping the tip into the photocurable resin composition <NUM> already injected in the resin filling space <NUM>.

After the filling of the photocurable resin composition <NUM> is completed, the injection nozzle <NUM> is removed from the resin filling space <NUM>.

Next, as shown in <FIG>, curing light such as ultraviolet light is irradiated from the transparent panel <NUM> side to the resin filling space <NUM> to cure the photocurable resin composition <NUM> to form the cured resin layer <NUM>. Further, by irradiating curing light from the side surface of the laminated body <NUM> toward the opening <NUM>, the opening <NUM> is blocked by the cured resin layer <NUM>.

As a result, as shown in <FIG>, one optical member <NUM> and the transparent panel <NUM> of the multi-panel optical device 1B are laminated via the cured resin layer <NUM>. The other optical member <NUM> is also laminated on the transparent panel <NUM> via the cured resin layer <NUM> in the same process to complete the multi-panel optical device 1B (<FIG>). The single-panel optical device 1A can also be manufactured by the same process. The irradiation of the photocurable resin composition <NUM> with curing light may be performed a plurality of times as required.

In such a multi-panel optical device 1B, the display region side of the light shielding portion <NUM> is a display portion <NUM> for transmitting an image displayed on the display region of the optical member <NUM>, and the display portion <NUM> is formed with the light transmitting wall <NUM> and the cured resin layer <NUM>. Further, in the display portion <NUM>, since the wall <NUM> and the cured resin layer <NUM> are formed of the same resin composition, the interface between the wall <NUM> and the cured resin layer <NUM> is not visible, and display properties and visibility are not impaired. The same applies to the single-panel optical device 1A.

In the multi-panel optical device 1B, the wall <NUM> is formed in contact with the light shielding portion <NUM>, and the resin filling space <NUM> surrounded by the wall <NUM> is filled with the photocurable resin composition <NUM>. That is, the resin filling space <NUM> filled with the photocurable resin composition <NUM> is exposed on the side of the transparent panel <NUM> without causing blind spots. Therefore, even when the display portions <NUM> are disposed close to each other by sharing one side of the light shielding portion <NUM>, the photocurable resin composition <NUM> in the resin filling space <NUM> can be irradiated with curing light through the transparent panel <NUM>, thereby eliminating uncured portions.

In the multi-panel optical device 1B, a plurality of optical members <NUM> each having the wall <NUM> formed thereon may be simultaneously bonded to the transparent panel <NUM> to form a laminated body <NUM>. Further, in the multi-panel optical device 1B, the photocurable resin composition <NUM> may be injected into each resin filling space <NUM> of the laminated body <NUM> formed by laminating the plurality of optical members <NUM> and may be cured simultaneously. Thus, the manufacturing time can be reduced.

As shown in <FIG>, in the method for manufacturing the optical device according to the present technology, the opening <NUM> of the wall <NUM> is formed with a projecting portion 13a extending outside the resin filling space <NUM> surrounded by the wall <NUM>. By filling the photocurable resin composition <NUM> up to the projecting portion 13a, the photocurable resin composition <NUM> is sufficiently spread over the entire of the resin filling space <NUM> surrounded by the wall <NUM>.

Further, although the wall <NUM> is formed on the optical member <NUM> side in the above embodiment, the method for manufacturing an optical device according to the present technology may form the wall <NUM> on the transparent panel <NUM> side, as shown in <FIG>. In this case, the transparent panel <NUM> is preferably formed flat to form the wall <NUM> at a uniform height over the entire length.

Although the embodiment described above injects the photocurable resin composition <NUM> by inserting the injection nozzle <NUM> through the opening <NUM>, in the method for manufacturing the optical device according to the present technology, as shown in <FIG>, the elastic wall <NUM> may be pierced with the hollow needle <NUM>, and the photocurable resin composition <NUM> may be injected into the resin filling space <NUM> through the hollow needle <NUM>. The hollow needle <NUM> has a pointed tip like an injection needle to pierce the wall <NUM>, and the photocurable resin composition <NUM> is injected from the tip part inserted into the resin filling space <NUM>. Since the wall <NUM> has elasticity and adhesiveness, it is closely contact with the hollow needle <NUM>, so that the photocurable resin composition <NUM> does not leak out from the hole pierced by the hollow needle <NUM>. Further, as the photocurable resin composition <NUM> is injected, the air in the resin filling space <NUM> is exhausted from the opening <NUM>.

Thus, the opening diameter of the opening <NUM> can be limited to the minimum diameter necessary for exhaust, and the leakage of the photocurable resin composition <NUM> from the opening <NUM> can be suppressed. Further, the photocurable resin composition <NUM> may be injected in a state in which the tip of the hollow needle <NUM> is dipped in the photocurable resin composition <NUM> already injected in the resin filling space <NUM>, so that the photocurable resin composition <NUM> can be injected at a high speed while preventing the mixing of air.

Although the position pierced by the hollow needle <NUM> may be any position in the wall <NUM>, the position is preferably lower position of the resin filling space <NUM> on the side opposite to the opening <NUM> as shown in <FIG> in order to inject the photocurable resin composition <NUM> in a state where the tip of the hollow needle <NUM> is dipped in the photocurable resin composition <NUM> already injected in the resin filling space <NUM>.

The wall <NUM> is preferably formed so that the portion pierced by the hollow needle <NUM> is thicker than other portions of the wall <NUM>. Thus, leakage of the photocurable resin composition <NUM> from the hole pierced by the hollow needle <NUM> can be prevented further effectively.

Further, in the method for manufacturing the optical device according to the present technology, the filling step of filling the resin filling space <NUM> with the photocurable resin composition <NUM> and the curing step of curing the photocurable resin composition <NUM> filling the resin filling space <NUM> may be performed in parallel. That is, while the resin filling space <NUM> is filled with the photocurable resin composition <NUM>, the photocurable resin composition <NUM> filling the resin filling space <NUM> may be irradiated with curing light to sequentially proceed the curing reaction.

By sequentially curing the photocurable resin composition <NUM> before the entire resin filling space <NUM> is filled, the increase in the internal pressure due to the filling of the uncured photocurable resin composition <NUM> into the resin filling space <NUM> can be suppressed, the load applied on the transparent panel <NUM> and the optical member <NUM>, which are becoming thinner, can be reduced, and the cured resin layer <NUM> can be formed to a uniform thickness.

Further, by carrying out the filling step and the curing step of the photocurable resin composition <NUM> in parallel, the manufacturing time can be reduced.

Moreover, according to the method for manufacturing the optical device according to the present technology, in the step of filling the resin filling space <NUM> with the photocurable resin composition <NUM>, the air in the resin filling space <NUM> may be sucked through the opening <NUM> to reduce the pressure. Thus, the photocurable resin composition <NUM> filling the resin filling space <NUM> is prevented from being mixed with air, and the resin filling space <NUM> can be filled with the photocurable resin composition <NUM> at a high speed, thereby reducing the filling time.

Furthermore, in the method for manufacturing the optical device according to the present technology, two openings <NUM> may be provided as an injection hole for injecting the photocurable resin composition <NUM> and an exhaust hole for exhausting air in the resin filling space <NUM>. The injection hole and the exhaust hole may be provided close to each other or may be provided apart from each other as long as both holes can be directed vertically upward at the filling step of the photocurable resin composition <NUM>.

Furthermore, in the method for manufacturing an optical device according to the present technology, in a case that the laminated body <NUM> is tilted so that the opening <NUM> is positioned at the uppermost position to inject the photocurable resin composition <NUM> as shown in <FIG>, the laminated body <NUM> may be returned to the horizontal position when the curing light is applied to the resin filling space <NUM> as shown in <FIG>. Thus, the tilting of the laminated body <NUM> can prevent the unfilled portion of the photocurable resin composition <NUM> from being formed in the vicinity of the opening <NUM> of the resin filling space <NUM>. Accordingly, the photocurable resin composition <NUM> is injected up to the opening <NUM> so that the cured light can be irradiated in a state in which the entire display area is filled with the photocurable resin composition <NUM>.

In the structure according to the present invention, in which the projecting portion 13a is formed in the opening <NUM> as shown in <FIG>, in a case that the laminated body <NUM> is tilted so that the opening <NUM> is positioned at the uppermost position to inject the photocurable resin composition <NUM>, the laminated body <NUM> may be returned to the horizontal position when the curing light is applied to the resin filling space <NUM> as shown in <FIG>.

Next, examples of forming a multi-panel optical device by using the present technology will be described. In the present example, one cover glass as the transparent panel <NUM> and two liquid crystal displays (LCD) as the optical member <NUM> are prepared, and the respective liquid crystal displays are bonded to the one cover glass via an ultraviolet-curable cured resin layer to form a multi-panel optical device. On the cover glass, black frame-shaped light shielding portions are formed at positions corresponding to the periphery of the display area of each LCD.

Next, the liquid crystal display is placed on the table of a dispenser applicator. Then, as the photocurable resin composition constituting the wall <NUM>, an optical elastic resin (Product Name CA <NUM>; manufactured by Dexerials Corporation) having a viscosity of <NUM>,<NUM> mPa*S was set in an injection nozzle (manufactured by Musashi Engineering).

Next, the optical elastic resin was applied to the display surface of the LCD under the conditions of a gap between the injection nozzle and the LCD of <NUM>, a dispensing pressure of <NUM> MPa, and an application speed of <NUM>/sec. In the present example, the optical elastic resin was applied in a substantially frame-like shape corresponding to the light shielding portion, and is applied at a position offset by <NUM> outside from the opening of the frame-shaped light shielding portion formed on the cover glass. A part of the frame shape is not applied with the optical elastic resin to define the opening.

Immediately after the application, the optical elastic resin was irradiated with ultraviolet light (<NUM>,<NUM> mJ/cm<NUM>) and cured. As a result, the wall having a height of about <NUM> and a width of about <NUM> was formed.

Then, the cover glass was fixed in the vertical direction by a fixing plate, the back surface of the LCD having the wall formed on the display surface side was fixed to another fixing plate, the cover glass and the LCD are aligned and bonded so as to have a gap of <NUM>, thereby forming a laminated body having a resin filling space. Further, the cover glass and the LCD were pressed to deform the wall by about <NUM> in height. As a result, the wall was deformed in accordance with the unevenness of the upper surface, brought into tight contact with the cover glass and the LCD, and protruded from the upper surface of the light shielding portion to the display region side by <NUM>.

Next, the injection nozzle was inserted from the opening to fill the resin filling space with the photocurable resin composition constituting the cured resin layer. As the photocurable resin composition, 18V028 having a viscosity of <NUM> mPa*S manufactured by Dexerials Corporation was used. As the injection nozzle # <NUM> Musashi Engineering <NUM> cc syringe was used.

The filling step was carried out in a state in which the laminated body was stood up so that the surface direction was vertical and tilted so that the opening was positioned at the uppermost position. The filling step was completed when the photocurable resin composition was injected up to the opening.

Then, the laminated body was irradiated with a predetermined amount of ultraviolet light (<NUM>,<NUM> mJ/cm<NUM>) from the cover glass side to cure the photocurable resin composition. Further, the opening was irradiated with a predetermined amount of ultraviolet light (<NUM>,<NUM> mJ/cm<NUM>) to cure the photocurable resin composition filling the opening. As a result, an optical device in which the cover glass and the LCD are bonded together via a cured resin layer was obtained. Thereafter, the fixing member on the LCD side was released. The above-described steps were repeated to obtain a multi-panel optical device.

In the multi-panel optical device thus obtained, no leakage of the photocurable resin composition was observed, the bonding strength between the cover glass and the LCD was sufficient, and the curing of the wall on the upper surface of the light shielding portion was confirmed.

Claim 1:
A method for manufacturing an optical device (<NUM>) in which an optical member (<NUM>) and a transparent panel (<NUM>) are bonded together via a cured resin layer (<NUM>), comprising:
a step of forming, on one of the optical member (<NUM>) and the transparent panel (<NUM>), a wall (<NUM>) surrounding a forming region for the cured resin layer (<NUM>) and having at least one opening (<NUM>);
a step of laminating the optical member (<NUM>) and the transparent panel (<NUM>) to form a laminated body (<NUM>) in which a resin filling space (<NUM>) surrounded by the wall (<NUM>) is formed between the optical member (<NUM>) and the transparent panel (<NUM>);
a step of filling the resin filling space (<NUM>) of the laminated body (<NUM>) with a photocurable resin composition (<NUM>); and
a step of curing the photocurable resin composition (<NUM>) to form the cured resin layer (<NUM>),
characterized in that
the opening (<NUM>) of the wall (<NUM>) is provided with a projecting portion (13a) extending outside the resin filling space (<NUM>) and surrounded by the wall (<NUM>).