JP4239245B2 - Manufacturing method of lattice lens array - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a prism sheet used for various display panels, a lens array of a three-dimensional display panel, and a lattice lens array used for optical components such as a CCD.
[0002]
[Prior art]
Conventionally, as a method for producing a lens array, (1) a method of producing a mold by cutting a metal with an NC machine tool or the like and producing it by stamping, and (2) heating and melting the tip of a glass fiber (3) A method of bundling after processing into a convex lens shape, (4) A method of forming by chemical etching, (4) A method of giving a lens effect by partially changing the refractive index of the material by sputtering or the like, (5) A method is known in which metal particles and the like processed into a spherical shape are mechanically arranged and then mold-made to produce a replica mold and die-molded.
[0003]
The methods (1), (2), and (5) are unsuitable for producing a large-area lens array, and the methods (1) and (3) are difficult to improve the surface smoothness. The methods (2) and (4) have a small degree of freedom in terms of condensing function design as a lens.
Each method has a problem that it is difficult to stably produce a large-area lens array at a low cost.
[0004]
[Problems to be solved by the invention]
The present invention has been made in view of the above problems, stably lens array having a large area, and an object thereof to provide a manufacturing how the lattice-like lens array can be manufactured at low cost.
[0005]
[Means for Solving the Problems]
In order to solve the above-mentioned problems in the present invention, first, a first aspect of the present invention is a method for manufacturing a lattice-shaped lens array, which includes the following steps.
(A) A step of forming a line-shaped relief having a concavo-convex shape in a specific direction with a photosensitive resin on a support.
(B) A photomask on which a line-shaped pattern is formed is placed on the line-shaped relief so as to intersect the line-shaped relief, exposed at a predetermined exposure amount, and light is applied to the line-shaped relief. Forming a cured latent image pattern;
(C) A step of forming a lens having a predetermined shape by heat-treating the line-like relief on which the photocured latent image pattern is formed at a predetermined temperature.
(D) A step of forming a lattice lens array on the support by exposing the entire surface with a predetermined exposure amount and curing the lens having the predetermined shape.
[0006]
According to a second aspect of the present invention, a replica mold is manufactured using the lattice lens array manufactured by the method of the first aspect as a mother mold, and a lens array is manufactured by stamping a transparent sheet or film substrate. This is a method for manufacturing a grid-like lens array.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIGS. 1A to 1E are schematic perspective views showing manufacturing steps of an embodiment of the lattice lens array of the present invention in the order of steps, and FIGS. 2A to 2G are lattice shapes of the present invention. FIG. 3A to FIG. 3E are schematic cross-sectional views showing the manufacturing process of one embodiment of the lattice lens array of the present invention in the order of steps. Respectively.
[0009]
In the method for manufacturing a lattice lens array according to the present invention, first, a line-shaped relief 1 having a concavo-convex shape in a specific direction made of a photosensitive resin is formed on a support 2 (see FIG. 1A).
[0010]
As the support 2, plates, sheets or films of any material including organic and inorganic materials such as metals, polymer materials, glass and ceramics can be used as long as the adhesion to the line-shaped relief 1 is sufficiently satisfied. It can be used.
The shape of the line-shaped relief 1 is preferably a curved lenticular type as shown in FIG. 1A, but is not limited to this, and may be a triangular shape, a rectangular shape, or other polygonal shapes. .
[0011]
Furthermore, as a method for forming the line-shaped relief 1, a photolithography method, a printing method, a transfer method, an embossing method, and the like can be used. Specifically, a photosensitive resin layer is formed from a photosensitive resin solution by knife coating, roll coating, bar coating, spin coating, etc., and a relief having a predetermined shape is produced by patterning treatment such as pattern exposure and development. Law. Alternatively, a method for producing a relief having a predetermined shape made of a photosensitive resin by using a general printing technique such as screen printing or gravure coating. Alternatively, a method for producing a relief having a predetermined shape made of a photosensitive resin using a transfer technique. Alternatively, there is a method of producing a relief having a predetermined shape by press-molding a photosensitive resin layer formed on a support using a cutting die and a replica die. In order to produce a line-shaped relief made of a photosensitive resin on a long film, etc., a photosensitive resin layer is formed on the long film by roll coating or the like, and is embossed using a roll-shaped cutting die. Law is an effective method.
[0012]
Further, the photosensitive resin forming the line-like relief 1 is obtained by adding a small amount of a photopolymerization initiator to a mixture of a general thermoplastic resin and an acrylate or methacrylate that performs at least two functional and good crosslinking reactions. Things can be used. Specifically, acrylic resins, styrene-acrylic copolymer resins, polyester resins, polyvinyl butyral, polycarbonate resins, vinyl chloride-vinyl acetate copolymer resins, styrene resins, vinyl chloride resins, acrylonitrile-styrene copolymer resins, A thermoplastic polyurethane resin or the like can be used. Also, acrylate or methacrylate alone can be used as long as it is a thermoplastic resin that exhibits a solid state at room temperature. For example, various urethane acrylate and methacrylate oligomers, various acrylates and methacrylates having an isocyanurate ring structure in the molecule, epoxy acrylates and methacrylates having a structure such as bisphenol A and bisphenol S in the molecule, polybutadiene urethane methacrylate, polystyrylethyl Examples thereof include methacrylate and the like, and an aqueous UV curable resin and the like can also be used.
[0013]
Photopolymerization initiators include self-cleavable compounds represented by derivatives such as benzoin, benzyl ketal, and acetophenone, and various hydrogen abstraction photopolymerization initiators having molecular structures such as benzophenone, aromatic ketone, and Michler's ketone. Is preferably added, and can be used in combination with various sensitizers as required.
[0014]
Next, a photomask 3 on which a line-shaped pattern is formed so as to intersect with the line-shaped relief 1 is placed, brought into close contact, and exposed with a predetermined exposure amount to form a photocured latent image pattern 5 (see FIG. 1 (b) and (c)).
Here, as a method for pattern exposure of the line-shaped relief 1, a pattern exposure method in which a line pattern having a continuous density gradation in the pattern width direction is exposed through a photomask, or intensity modulation is added. A laser beam scanning exposure method or the like can be used.
[0015]
Next, the line-shaped relief 1 on which the photocured latent image pattern 5 is formed is heated at a predetermined temperature to form a lens 6 having a predetermined shape (see FIG. 1D). This shows a process of thermally developing the photocured latent image pattern 5 recorded on the line relief 1 by pattern exposure. That is, by heating the line-shaped relief 1 in which regions having different degrees of curing are formed by pattern exposure under predetermined temperature conditions, the line-shaped relief 1 is softened and deformed according to the degree of photocuring, and a predetermined shape is formed between regions having different degrees of curing. The lens 6 is formed. The lens 6 shows a lens array after being softened and deformed. Since the exposed region is cured, the shape of the convex portion of the line-shaped relief 1 is maintained without being deformed even when heated.
[0016]
Next, the entire surface is exposed with a predetermined exposure amount to cure the lens 6 to form a lattice lens array 8 on the support (see FIG. 1E). This is to form a lattice lens array 8 by fixing and curing the lens 6 of a predetermined shape formed by the heat treatment by the entire surface exposure.
[0017]
Next, a method for manufacturing a lattice lens array according to claim 2 of the present invention will be described.
In the present invention, a replica mold is manufactured using the grid lens array manufactured by the above method as a mother mold, and a grid lens array (replicated product) is manufactured by stamping.
A lattice lens array (replicated product) produced by this method can be selected based on the optical characteristics (transmittance, refractive index, etc.) of the lattice lens array, and the selection range of the lattice lens array substrate is claimed. More broader than the method of item 1.
[0018]
First, a thin film conductive layer 12 made of copper, aluminum, gold, silver, or an alloy containing these metals and the like is provided on the surface of a lattice lens array matrix 11 (see FIG. 2A) manufactured by the above method (see FIG. 2A). (Refer FIG.2 (b)). As a film forming method of the thin film conductive layer 12, a generally well-known vacuum deposition method, sputtering method, ion plating method, or the like can be used. The film thickness is suitably in the range of 100 to 10000 mm.
[0019]
Next, electrolytic plating is performed using the thin film conductive layer 12 as a plating electrode to form a metal plating layer 13 having a predetermined thickness on the lattice lens array matrix 11 (see FIG. 2C). Further, the lattice-shaped lens array matrix 11 is peeled off, and the thin film conductive layer 12 is removed to obtain a replica mold 13a (see FIGS. 2D to 2E).
[0020]
Next, a transparent sheet or film base material made of a thermoplastic resin or a thermosetting resin is heated and pressurized by the replication mold 13a to perform embossing (see FIG. 2 (f)), and from the replication mold 13a. By peeling, a lattice lens array (replicated product) 14a is obtained (see FIG. 2G).
[0021]
Further, as another method of embossing, a photosensitive resin layer 23 made of an ultraviolet curable resin is formed on a support 22 made of a transparent sheet or film (see FIG. 3A), and the replica mold 13a is formed. Adhering, heating and pressurizing to form a molded photosensitive resin layer 23a (see FIG. 3B). Further, the photosensitive resin layer 23a molded by irradiating ultraviolet rays from the support 22 side is cured to form a lens array 23b (see FIG. 3C). Furthermore, by separating the replica mold 13a, a lattice lens array (replicated product) 23c can be obtained on the support 22 (see FIG. 3D).
[0022]
Furthermore, as another method of the stamping molding, a photosensitive resin layer 23 made of an ultraviolet curable resin is formed on a support 22 made of a transparent sheet or film subjected to a surface release treatment, and the replication mold 13a. And press-molding the photosensitive resin layer by heating and pressing. By irradiating ultraviolet rays from the side of the support 22, the molded photosensitive resin layer 23 a is cured, the replica mold 21 is peeled off, and a lattice lens array (replicated product) 23 c is formed on the support 22. By peeling the body 22, a single lattice lens array (replicated product) 23c (see FIG. 3E) can be obtained.
[0023]
【Example】
Hereinafter, the present invention will be described in detail by way of examples.
<Example 1>
First, a photosensitive resin solution A shown below is applied onto a support 2 made of a PMMA sheet having a thickness of 200 μm using a roll coater, dried at 80 ° C. for 25 minutes, and then a photocurable thermoplastic resin composition having a thickness of 50 μm. The photosensitive resin layer which consists of was formed.
[0024]
Composition resin of photosensitive resin solution A (Dianar BR-80 (Mitsubishi Rayon Co., Ltd.)) 30 parts by weight Acrylic resin (Dianal BR-77 (Mitsubishi Rayon Co., Ltd.)) 35 parts by weight Pentaerythritol hexaacrylate ………………… 30 parts by weight Tris (acryloxyethyl) isocyanurate ………………… 5 parts by weight photopolymerization initiator (Irgacure-651 (manufactured by Ciba Geigy))… 11 parts by weight 2-butanone… ………………………………………………………… 150 parts by weight toluene ……………………………………………………………… ... 100 parts by weight [0025]
Next, a nickel-plated copper plate was cut with a diamond bit to form a scallop-like groove having a width of 100 μm and a depth of 25 μm, and a mold for producing the line-shaped relief 1 was produced.
[0026]
Next, the uneven surface of the mold is brought into intimate contact with the photosensitive resin layer on the support ² , and flat pressure pressing is performed under the conditions of a pressure of 10 kg / cm ² , a temperature of 80 ° C., and a pressing time of 60 seconds, and the pressure is kept constant. After rapidly cooling to room temperature while maintaining the temperature, the mold was peeled to form a line-shaped relief 1 made of a photosensitive resin on the support 2.
[0027]
Next, a photomask 3 on which a line-shaped pattern having a continuous density gradation in the width direction is placed so as to intersect with the line-shaped relief 1 on the support 2, and after adhering, a high-pressure mercury lamp is installed. The photocured latent image pattern 5 was formed on the line-shaped relief 1 by irradiating with ultraviolet rays at an exposure amount of 1200 mJ / cm ² .
[0028]
Next, the line-shaped relief 1 on which the photocurable latent image pattern 5 was formed was heat-treated at 100 ° C. for 15 minutes to form a lens 6 having a predetermined shape. Further, the entire surface was exposed with an exposure amount of 500 mJ / cm ² to cure the lens 6, and a lattice-like lens array 8 was obtained on the support 2. Here, as a result of observing the lens shape of the lattice lens array 8, it was confirmed that a regular lattice lens array as shown in FIG. 1 (e) was formed.
[0029]
<Example 2>
A description will be given of an example in which a replica mold is manufactured using the grid lens array obtained in Example 1 as a mother mold, and stamped to obtain a grid lens array (replicated product).
First, a thin-film conductive layer 12 made of an Au film having a thickness of about 200 mm was formed on the surface of the lattice lens array matrix 11 obtained in Example 1 by vacuum deposition.
[0030]
Next, electrolytic Ni plating was performed using the thin film conductive layer 12 as a plating electrode to form a Ni plating layer 13 having a thickness of about 250 μm. Further, the lattice-shaped lens array matrix 11 was peeled off, and the thin film conductive layer 12 was removed to produce a replica mold 13a.
[0031]
Next, the replica mold 13a is brought into close contact with a PMMA sheet having a thickness of 100 μm, and is pressed and heated under conditions of a pressure of 10 kg / cm ² and a temperature of 150 ° C. for 3 minutes, and is then molded into a lattice lens array. (Replica product) 14a was obtained.
[0032]
<Example 3>
A photosensitive resin solution B shown below is applied onto a support 22 made of a polyester film having a thickness of 100 μm and subjected to surface release treatment using a roll coater, and dried to form a UV-curable photosensitive resin having a thickness of 40 μm. Layer 23 was formed.
[0033]
Composition of photosensitive resin solution B EO-modified trimethylolpropane triacrylate ... 70 parts by weight triethylene glycol diacrylate ... 30 parts by weight photopolymerization initiator (Dorocur 1173 (Ciba Geigy) 5 parts by weight [0034]
Next, the replica mold 13a obtained in Example 2 was closely attached to the photosensitive resin layer 23, heated and pressurized to form the molded photosensitive resin layer 23a, and then from the support 22 side. The photosensitive resin layer 23a molded by irradiating with an exposure amount of 600 mJ / cm ² was cured to form a lens array 23b.
Next, the replica mold 13a and the support 22 were peeled off to obtain a lattice lens array (replica product) 23c.
[0035]
【The invention's effect】
As described above, the method for forming a lattice lens array of the present invention forms a lens shape by pattern exposure and heat treatment of a line-shaped relief made of a photosensitive resin, so that a high quality large area, small lot lens is formed. Products can be supplied at a lower cost.
Furthermore, by devising the line-shaped relief shape, line-shaped pattern design, and exposure method, the lens size, plane shape, etc. can be continuously changed within the lens sheet surface, or the lens can be applied only to a specific part of the sheet. Can be formed.
Furthermore, if a line-like relief is produced by a cylinder roll type stamping process, a lattice lens array of a long film can be easily produced.
[Brief description of the drawings]
FIGS. 1A to 1E are schematic perspective views showing a manufacturing process of an embodiment of a lattice lens array of the present invention in the order of steps.
FIGS. 2A to 2G are schematic cross-sectional views showing the manufacturing process of an embodiment of the lattice lens array of the present invention in the order of steps.
FIGS. 3A to 3E are schematic cross-sectional views showing the manufacturing process of an embodiment of the lattice lens array of the present invention in the order of steps.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Line-shaped reliefs 2 and 22 which consist of photosensitive resin ... Support 3 ... Photomask 4 with line-shaped pattern formed ... Ultraviolet light 5 ... Photocuring latent image pattern 6 ... Lens 8... Lattice lens array 9... Ultraviolet light 11 for entire surface exposure... Lattice lens array matrix 12. Thin film conductive layer 13. Metal plating layer 13 a. Transparent sheet or film substrate 14a ... Lattice lens array (replicated product)
23... Photosensitive resin layer 23 a... Molded photosensitive resin layer 23 b... Lens array 23 c.

Claims (2)

A method for manufacturing a lattice lens array, comprising the following steps.
(A) A step of forming a line-shaped relief having a concavo-convex shape in a specific direction with a photosensitive resin on a support.
(B) A photomask on which a line-shaped pattern is formed is placed on the line-shaped relief so as to intersect the line-shaped relief, exposed at a predetermined exposure amount, and light is applied to the line-shaped relief. Forming a cured latent image pattern;
(C) A process of forming a lens having a predetermined shape by heat-treating the line-shaped relief on which the photocured latent image pattern is formed at a predetermined temperature.
(D) A step of forming a lattice lens array on the support by exposing the entire surface with a predetermined exposure amount to cure the lens having the predetermined shape.   A grid-shaped lens array produced by using the grid-shaped lens array produced by the method according to claim 1 as a matrix and producing a lens array by stamping on a transparent sheet or film substrate Array manufacturing method.

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