JP4581328B2 - Polymer optical waveguide and optical element manufacturing method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a polymer optical waveguide, an optical element manufacturing method, and an optical element, and more particularly to a polymer optical waveguide and an optical element excellent in flexibility.
[0002]
[Prior art]
The polymer waveguide manufacturing method includes (1) a method of impregnating a film with a monomer and selectively exposing the core portion to change the refractive index to bond the films (selective polymerization method), and (2) a core layer. And a method of forming a cladding portion using reactive ion etching after applying the cladding layer (RIE method), and (3) exposure and development using an ultraviolet curable resin in which a photosensitive material is added to a polymer material. A method using a photolithography method (direct exposure method), (4) a method using injection molding, (5) a method of changing the refractive index of the core portion by exposing the core portion after applying the core layer and the clad layer ( Photo bleaching method) has been proposed.
However, the selective polymerization method (1) has a problem in film lamination, and the methods (2) and (3) are expensive because the photolithographic method is used. There is a problem in the accuracy of the diameter. Further, the method (5) has a problem that a sufficient refractive index difference between the core layer and the clad layer cannot be obtained.
At present, the practical methods excellent in performance are only the methods (2) and (3), but there is a problem of cost as described above. None of the methods (1) to (5) is applicable to forming a polymer waveguide on a flexible plastic substrate having a large area.
[0003]
In addition, as a method of manufacturing a polymer optical waveguide, a core substrate is formed by filling a polymer substrate material for a core into a pattern substrate (cladding) on which a groove pattern serving as a capillary is formed, and then curing the core layer. In this method, the polymer precursor material is thinly filled and cured not only in the capillary groove but also between the pattern substrate and the flat substrate. As a result of forming a thin layer having the same composition as the core layer, there is a problem that light leaks through the thin layer.
As one method for solving this problem, Debit Hart uses a clamping jig to fix the pattern substrate on which a groove pattern serving as a capillary is formed and a flat substrate, and further, the contact portion between the pattern substrate and the flat substrate. A method of manufacturing a polymer optical waveguide by sealing the resin with a resin and then reducing the pressure and filling a capillary with a monomer (diallyl isophthalate) solution was proposed (see Patent Document 1 below). In this method, instead of using the polymer precursor material as the core forming resin material, the viscosity of the filling material is reduced by using a monomer, and the capillary is filled using the capillary phenomenon so that the monomer is not filled except the capillary. It is a method to do.
However, since this method uses a monomer as the core forming material, there is a problem that the volumetric shrinkage when the monomer is polymerized to become a polymer is large, and the transmission loss of the polymer optical waveguide is increased. In addition, this method is a complicated method such as fixing the pattern substrate and the flat substrate with a clamp, or additionally sealing the contact portion with resin, so that it is not suitable for mass production, and as a result, cost reduction is expected. I can't. Further, it cannot be applied to the production of a polymer optical waveguide using a film having a thickness of mm order or 1 mm or less as a clad.
[0004]
Recently, George M. Whitesides and others at Harvard University have proposed a method called capillary micromolding as one of the soft lithography as a new technology for creating nanostructures. This is because a master substrate is made using photolithography, and the nanostructure of the master substrate is copied to a PDMS mold using the adhesion and easy peelability of polydimethylsiloxane (PDMS). This is a method of pouring and solidifying a liquid polymer. The following non-patent document 1 describes detailed explanation articles.
[0005]
A patent on capillary micromolding has been filed by Kim Enoch et al. Of George M. Whitesides group at Harvard University (see Patent Document 2 below). However, even if the manufacturing method described in this patent is applied to the manufacture of a polymer optical waveguide, the core portion of the optical waveguide has a small cross-sectional area, so that it takes time to form the core portion and is not suitable for mass production. In addition, when the monomer solution is polymerized into a polymer, the volume is changed, the core shape is changed, and the transmission loss is increased.
[0006]
B. Michel et al. Of the IBM Zurich Research Institute have proposed a high-resolution lithography technique using PDMS, and reported that this technique can achieve a resolution of several tens of nanometers. Detailed commentary articles are described in Non-Patent Document 2 below.
In this way, soft lithography technology using PDMS and capillary micromolding are technologies that have recently attracted attention as nanotechnology mainly in the United States.
[0007]
However, when an optical waveguide is manufactured by using the micromold method as described above, the volume shrinkage during curing is reduced (thus, transmission loss is reduced), and a filling liquid (monomer or the like) is used to facilitate filling. It is impossible to achieve a low viscosity. Therefore, if priority is given to reducing the transmission loss, the viscosity of the filling liquid cannot be reduced below a certain limit, the filling speed becomes slow, and mass production cannot be expected. The micromold method is based on the premise that a glass or silicon substrate is used as the substrate, and does not consider the use of a flexible film substrate.
[0008]
On the other hand, Patent Document 3 below shows a method for producing a polymer optical waveguide by using a mold having low rigidity. In this method, a second convex mold is produced from the first concave mold, a resin is applied to the second convex mold and cured to form a first clad having a concave portion that becomes a core pattern, and the second convex mold. After the film is peeled off, the core is formed by coating and curing the resin in the recesses that become the core pattern, and then the resin is further coated and cured to form the second cladding. However, only the recesses are filled with the core resin. It is difficult to make a fine core pattern with high accuracy.
[0009]
By the way, recently, in IC technology and LSI technology, in order to improve the operation speed and the degree of integration, instead of performing high-density electrical wiring, optical wiring is performed between equipment devices, between boards in equipment equipment, and in chips. Is attracting attention.
As an element for optical wiring, for example, in Patent Document 4 below, a polymer optical waveguide having a core and a clad surrounding the core is provided with a light emitting element and a light receiving element in the core / cladding direction, and the light emitting element An optical element having an incident side mirror for causing light from the core to enter the core and an output side mirror for causing the light from the core to be emitted to the light receiving element, the light receiving element from the light emitting element and the light receiving element from the output side mirror An optical element is described in which a cladding layer is formed in a concave shape at a position corresponding to the optical path leading to, and the light from the light emitting element and the light from the exit side mirror are converged. Further, in Patent Document 5 below, in an optical element in which light from a light emitting element is incident on a core end face of a polymer optical waveguide having a core and a clad surrounding the core, the light incident end face of the core faces the light emitting element. An optical element that is formed to have a convex surface and converges light from the light emitting element to suppress waveguide loss is described.
Further, Patent Document 6 below describes an optoelectronic integrated circuit in which a polymer optical waveguide circuit is directly assembled on a photoelectric fusion circuit substrate in which electronic elements and optical elements are integrated.
[0010]
By the way, if the above-described elements can be bent in the optical wiring and incorporated in the apparatus, it becomes possible to increase the degree of freedom when considering the assembly of the optical wiring. Will increase the degree.
However, since the optical element and the optoelectronic integrated circuit are not flexible, it is impossible to incorporate them into the apparatus by bending them. Further, the optical element and the optoelectronic integrated circuit need to form a convex end face of the core or use a mirror together, and thus have to adopt a complicated structure. The reason why it is necessary to make the core end surface convex as described above or to collect light using a lens is that the semiconductor laser element as a light emitting element used in the optical element or the like generates a large amount of heat. If it is used simply in close contact with a polymer waveguide, heat will not escape and cause malfunction, so it is necessary to provide a gap between the polymer waveguide portion and the light emitting element to release the heat. On the other hand, there is a divergence angle in the spot of the semiconductor laser (thus, as the gap becomes larger, the light spreads and it becomes difficult to confine the light in the optical waveguide).
Furthermore, both the optical element and the optoelectronic integrated circuit include a polymer optical waveguide, but both are manufactured using a photolithography method, and the process is complicated and there are problems such as waste liquid. The load is also great.
[0011]
Thus, in addition to the flexible polymer optical waveguide sheet itself that has never been provided, a light emitting element is connected to the end face of the polymer optical waveguide sheet so as not to impair this flexibility. Thus, the idea of using an optical element for an optical wiring is not proposed at all.
[0012]
[Patent Document 1]
(Patent Publication No. 3151364)
[Patent Document 2]
US Pat. No. 6,355,198
[Patent Document 3]
JP 2002-31273 A
[Patent Document 4]
JP 2000-39530 A
[Patent Document 5]
JP 2000-39531 A
[Patent Document 6]
JP 2000-235127 A
[Non-Patent Document 1]
SCIENTIFIC AMERICAN SEPTEMBER 2001 (Nikkei Science December 2001 issue)
[Non-Patent Document 2]
IBM J. REV. & DEV. VOL. 45 NO. 5 SEPTEMBER 2001
[0013]
[Problems to be solved by the invention]
The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a method of manufacturing a polymer optical waveguide and an optical element by an easy and simplified method at an extremely low cost, and an optical element. There is to do.
[0014]
[Means for Solving the Problems]
  The above-described problems are solved by providing the following polymer optical waveguide manufacturing method, optical element manufacturing method, and optical element.
(1) 1) It is formed from a cured layer of a mold-forming curable resin and corresponds to the optical waveguide core convex portion.pluralA recess and thepluralAt one end of the recessIn commonIn the through hole for the fluid reservoir to communicate with and the other endIn commonA mold having two or more through-holes for vacuum suction that communicate with each other, wherein the through-hole for the reservoir and the through-hole for vacuum suction are formed on the surface of the mold and the surface on which the concave portion is formed. A step of preparing a mold, which is a hole penetrating the opposing surface, 2) a step of closely contacting the mold with a flexible film substrate for clad having good adhesion to the mold, and 3) flexibility of the clad The core-forming curable resin is filled into the through-hole at one end of the concave portion of the mold to which the film base is adhered, and the core-forming curable resin is sucked under reduced pressure from the through-hole at the other end of the concave portion of the mold. A step of filling the concave portion of the mold with resin, 4) a step of curing the filled core-forming curable resin, and peeling the mold from the flexible film base material for cladding. Form a clad layer on a flexible film substrate Degree, producing a polymer optical waveguide having a.
[0015]
(2) After the step (5), the step of forming a core surface having an optical mirror surface by cutting the end of the core is performed. Method.
(3) The aboveFor the sumpPenetrationHoleThe production of the polymer optical waveguide according to (1), wherein the cross-sectional area is larger on the side in contact with the clad flexible film substrate and becomes smaller as the clad flexible film substrate is separated from the clad flexible film substrate. Method.
[0016]
(4) The method for producing a polymer optical waveguide according to (1), wherein the clad flexible film substrate has a refractive index of 1.55 or less.
(5) The method for producing a polymer optical waveguide according to (1), wherein the clad flexible film substrate is an alicyclic olefin resin film.
(6) The method for producing a polymer optical waveguide according to (5), wherein the alicyclic olefin resin film is a resin film having a norbornene structure in the main chain and a polar group in the side chain. .
(7) The method for producing a polymer optical waveguide according to (1), wherein in the step (2), the clad flexible film substrate is held by a rigid body having high flatness.
[0017]
(8) The method for producing a polymer optical waveguide according to (1), wherein the mold-forming curable resin is liquid silicone rubber.
(9) The method for producing a polymer optical waveguide according to the above (1), wherein the surface energy of the mold is 10 dyn / cm to 30 dyn / cm.
(10) The method for producing a polymer optical waveguide according to (1), wherein the mold has a Share rubber hardness of 15 to 80.
(11) The method for producing a polymer optical waveguide according to (1), wherein the mold has a surface roughness of 0.1 μm or less.
(12) The method for producing a polymer optical waveguide according to (1), wherein the template is light transmissive in an ultraviolet region and / or a visible region.
[0018]
(13) The method for producing a polymer optical waveguide according to (1), wherein the clad layer is formed by applying a curable resin for clad and then curing.
(14) The method for producing a polymer optical waveguide according to (1), wherein the clad layer is formed by bonding a clad film with an adhesive having a refractive index close to that of the film.
(15) 1) It is formed from a cured layer of a mold-forming curable resin and corresponds to the optical waveguide core convex portion.pluralA recess and thepluralAt one end of the recessIn commonIn the through hole for the fluid reservoir to communicate with and the other endIn commonA mold having two or more through-holes for vacuum suction that communicate with each other, wherein the through-hole for the reservoir and the through-hole for vacuum suction are formed on the surface of the mold and the surface on which the concave portion is formed. A step of preparing a mold, which is a hole penetrating the opposing surface, 2) a step of closely contacting the mold with a flexible film substrate for clad having good adhesion to the mold, and 3) flexibility of the clad The core-forming curable resin is filled into the through-hole at one end of the concave portion of the mold to which the film base is adhered, and the core-forming curable resin is sucked under reduced pressure from the through-hole at the other end of the concave portion of the mold. A method for producing a polymer optical waveguide, comprising: filling a resin into a recess of the mold; and 4) curing a filled core-forming curable resin.
[0019]
(16) 1) It is formed from a cured layer of a curable resin for mold formation and corresponds to the convex portion of the optical waveguide core.pluralA recess and thepluralAt one end of the recessIn commonIn the through hole for the fluid reservoir to communicate with and the other endIn commonA mold having two or more through-holes for vacuum suction that communicate with each other, wherein the through-hole for the reservoir and the through-hole for vacuum suction are formed on the surface of the mold and the surface on which the concave portion is formed. A step of preparing a mold, which is a hole penetrating the opposing surface, 2) a step of closely contacting the mold with a flexible film substrate for clad having good adhesion to the mold, and 3) flexibility of the clad The core-forming curable resin is filled into the through-hole at one end of the concave portion of the mold to which the film base is adhered, and the core-forming curable resin is sucked under reduced pressure from the through-hole at the other end of the concave portion of the mold. A step of filling the concave portion of the mold with resin, 4) a step of curing the filled core-forming curable resin, and peeling the mold from the flexible film base material for cladding. Form a clad layer on a flexible film substrate Degree, 6) forming a cut core core end face with an optical mirror surface, 7) The method of producing an optical element having a step, to attach the light-emitting portion.
[0020]
(17) The method for manufacturing an optical element according to (16), wherein the core end surface is cut at 90 ° with respect to the core longitudinal direction, and the light emitting portion is directly connected to the core end surface.
(18) The optical element according to (16), wherein the end surface of the core is cut at 45 ° with respect to the longitudinal direction of the core to form a mirror surface, and light from the light emitting portion is guided to the core by the mirror surface. Manufacturing method.
(19) The method for manufacturing an optical element according to (16), further including a step of attaching an optical connector after the step of (7).
(20) A flexible polymer having a clad made of a flexible film substrate, a core made of a cured product of a core-forming curable resin provided on the clad, and a clad layer formed so as to cover the core An optical element in which a light emitting portion and an optical connector are provided on an optical waveguide sheet.
[0021]
DETAILED DESCRIPTION OF THE INVENTION
[Method for producing polymer optical waveguide]
  First, a method for producing a polymer optical waveguide will be described. The method for producing a polymer optical waveguide of the present invention is performed by the following steps.
1) It is formed from a cured layer of a mold-forming curable resin and corresponds to the optical waveguide core protrusion.pluralA recess and thepluralAt one end of the recessIn commonIn the through hole for the fluid reservoir to communicate with and the other endIn commonA mold having two or more through-holes for vacuum suction that communicate with each other, wherein the through-hole for the reservoir and the through-hole for vacuum suction are formed on the surface of the mold and the surface on which the concave portion is formed. A step of preparing a mold, which is a hole penetrating the opposing surface
2) A step of adhering a flexible film base material for clad (hereinafter sometimes simply referred to as a clad film base material) having good adhesion to the mold to the mold.
3) Filling the through hole at one end of the concave portion of the mold with the flexible film base material for clad in close contact, and filling the through hole at the other end of the concave portion of the mold with vacuum suction. Filling the mold recess with the core-forming curable resin
4) Step of curing the filled core-forming curable resin and peeling the mold from the clad flexible film substrate
5) A step of forming a clad layer on the clad flexible film substrate on which the core is formed.
[0022]
In the method for producing a polymer optical waveguide of the present invention, as described above, when the flexible film base material for clad having good adhesion to the mold is adhered to the mold, both are not fixed using a special means. However, the curable resin for forming the core without any gap between the mold and the base material for the clad other than the concave structure formed in the mold, except for the fixing means as described in the above-mentioned patent 3151364. The method of manufacturing a polymer optical waveguide according to the present invention is based on the discovery that the polymer optical waveguide can be made to enter only into the recess. Compared to a conventional method for producing a polymer optical waveguide, it is possible to produce a polymer optical waveguide at an extremely low cost. In the method for producing a polymer optical waveguide according to the present invention, a through hole is provided in the mold, and the core forming curable resin discharge side of the mold recess is sucked under reduced pressure, so that the adhesion between the mold and the film substrate is further improved. In addition, air bubbles can be avoided.
Therefore, according to the method for producing a polymer optical waveguide of the present invention, a flexible polymer optical waveguide with low loss loss and high accuracy and enabling free loading into various devices can be obtained at low cost. Furthermore, the shape of the polymer optical waveguide can be freely set.
[0023]
  Below, the manufacturing method of the polymer optical waveguide by this invention is demonstrated in order of a process. In the following, an example will be described in which two through holes communicating with one end and the other end of the concave portion corresponding to the convex portion are provided, but two or more through holes can be provided. For example, if you have one Y branch and three through holes, and if you have three Y branches and branch to one-to-eight, then you will have nine through holes and a curable resin for core formation in the recess. Need to be filled. Further, the branch includes a case of multistage.
1) It is formed from a cured layer of a mold-forming curable resin and corresponds to the optical waveguide core protrusion.pluralA recess and thepluralAt one end of the recessIn commonIn the through hole for the fluid reservoir to communicate with and the other endIn commonA mold having two or more through-holes for vacuum suction that communicate with each other, wherein the through-hole for the reservoir and the through-hole for vacuum suction are formed on the surface of the mold and the surface on which the concave portion is formed. A step of preparing a mold, which is a hole penetrating the opposing surface
  The production of the mold is preferably performed using a master having a convex portion corresponding to the optical waveguide core, but is not limited thereto. In the following, a method using the master will be described.
<Preparation of master>
  A conventional method, for example, a photolithography method can be used without particular limitation for producing a master having a convex portion corresponding to the optical waveguide core. Further, the method (Japanese Patent Application No. 2002-10240) for producing a polymer optical waveguide by the electrodeposition method or the photo-deposition method previously filed by the present applicant can also be applied to produce the master. The size of the convex portion corresponding to the optical waveguide formed on the master is appropriately determined according to the use of the polymer optical waveguide. For example, in the case of a single mode optical waveguide, a core of about 10 μm square is generally used, and in the case of a multimode optical waveguide, a core of about 50 to 100 μm square is generally used. An optical waveguide having a larger core part of about μm is also used.
[0024]
<Production of mold>
  As an example of mold production, a mold-forming curable resin layer was formed by applying or casting a mold-forming curable resin to the convex surface of the master produced as described above. Then, if necessary, a drying process is performed, a curing process is performed, and then the cured resin layer is peeled off from the master and a mold in which a concave portion corresponding to the convex portion is formed is taken.ofThrough holes communicating with one end and the other end of the recess(It is a hole penetrating the surface where the concave portion of the mold is formed and the surface facing the surface)The method of forming is mentioned. AbovePenetratingThe through hole can be formed, for example, by punching the mold into a predetermined shape. Even in the case of punched through-holes, the adhesion between the mold and the film base for cladding is good, and no gap is formed between the film base for cladding other than the mold recess. There is no risk of penetration of the curable resin.
  The thickness of the mold (cured resin layer) is appropriately determined in consideration of the handleability as a mold, but generally about 0.1 to 50 mm is appropriate.
  Further, it is desirable that the master is subjected to a release treatment such as application of a release agent in advance to promote peeling from the mold.
[0025]
The through-hole provided on the core-forming curable resin entry side has a function of storing liquid (core-forming curable resin). The through hole provided on the core-forming curable resin discharge side is used for vacuum suction for decompressing the mold recess when filling the resin into the mold recess. The shape and size of the penetration hole on the entry side are not particularly limited as long as the penetration hole communicates with the entry end of the recess and has the function of a liquid reservoir. Also, the shape and size of the through hole on the discharge side are not particularly limited as long as it communicates with the discharge end of the recess and can be used for vacuum suction.
[0026]
Since the through hole provided on the mold forming curable resin entrance side of the mold recess has a function of a liquid reservoir, when the mold is brought into close contact with the clad film base, the side in contact with the base is large. When it is made smaller as it gets away from the base material, the core-forming curable resin is filled in the recesses and, after curing, the mold and the base material can be easily separated. Since it is not necessary for the through hole on the core forming curable resin discharge side to have a function of a liquid reservoir, it is not particularly necessary to adopt such a cross-sectional structure.
[0027]
In addition, as another example of mold production, not only the projection corresponding to the optical waveguide core but also the projection for forming the through hole on the master (the height of this projection is the thickness of the cured layer of the mold-forming curable resin). The mold forming curable resin is applied to the master so that the projections for forming the through-holes penetrate the resin layer, and then the resin layer is cured, and then the cured resin layer is removed from the master. A method of peeling can be mentioned.
[0028]
FIG. 1 shows a schematic diagram of an example of a mold used in the present invention. FIG. 1A shows a plan view of the mold 20, and two through holes 26 and 28 provided in the mold concave portion 22 on the entrance side and the discharge side of the core-forming curable resin are punched holes. The planar shape is a circle. FIG. 1B shows a cross section of the mold cut along the mold longitudinal direction so that the mold recess 22 and the two through holes 26 and 28 can be seen. The side that comes into contact with the base material (the side on which the recesses are formed) is large, and the distance from the base material decreases. On the other hand, the through-hole 28 on the discharge side has a larger cross-sectional area on the side in contact with the clad film substrate (in accordance with the diameter of the vacuum suction pipe), but is not limited to such a cross-sectional structure. Absent.
[0029]
FIG. 2 is a perspective view showing an example of a master plate provided with a convex portion for forming a through hole. 10 is a master plate, 12 is a convex portion corresponding to the optical waveguide core, and 14a is a penetration on the core forming curable resin entrance side. The convex part for hole formation, 14b shows the convex part for through-hole formation by the side of resin discharge, respectively.
[0030]
The mold-forming curable resin used for mold production is such that the cured product can be easily peeled off from the master, has a certain level of mechanical strength and dimensional stability as a mold (repeated use), and maintains the concave shape. It is preferable to have hardness (hardness) and good adhesion to the clad film substrate. Various additives can be added to the mold-forming curable resin as necessary.
The mold-forming curable resin can be applied or cast on the surface of the master, and the projections corresponding to the individual optical waveguide cores formed on the master must be accurately copied. It is preferable to have a viscosity below a certain limit, for example, about 500 to 7000 mPa · s. (Note that the “mold-forming curable resin” used in the present invention also includes a resin that becomes a rubber-like body having elasticity after curing.) In addition, the solvent is used for viscosity adjustment, and the adverse effect of the solvent. Can be added to the extent that does not occur.
[0031]
As the mold-forming curable resin, from the viewpoint of releasability, mechanical strength / dimensional stability, hardness, and adhesion to the base material for cladding, the cured silicone rubber (silicone elastomer) or silicone resin is used. A curable organopolysiloxane is preferably used. The curable organopolysiloxane preferably contains a methylsiloxane group, an ethylsiloxane group, or a phenylsiloxane group in the molecule. Further, the curable organopolysiloxane may be a one-component type or a two-component type used in combination with a curing agent, or a thermosetting type or a room temperature curable type (for example, with moisture in the air). A material that cures), and other materials (such as ultraviolet curing) may be used.
[0032]
The curable organopolysiloxane is preferably a silicone rubber after curing, which is usually referred to as a liquid silicone rubber (“liquid” includes those with a high viscosity such as a paste). The two-part type used in combination with a curing agent is preferable. Among them, the addition type liquid silicone rubber cures uniformly and in a short time on the surface and inside, and there is no by-product at that time. Or, it is preferable because it is small and has excellent releasability and small shrinkage.
[0033]
Among the liquid silicone rubbers, liquid dimethylsiloxane rubber is particularly preferable from the viewpoints of adhesion, peelability, strength and hardness. In addition, since a cured product of liquid dimethylsiloxane rubber generally has a low refractive index of about 1.43, a mold made therefrom can be preferably used as a clad layer as it is without being peeled off from the clad substrate. . In this case, it is necessary to devise such that the mold, the filled core forming resin, and the clad substrate are not peeled off.
[0034]
The viscosity of the liquid silicone rubber is 500 from the viewpoint of accurately copying the convex portion corresponding to the optical waveguide core and facilitating defoaming by reducing the mixing of bubbles, and from the point of forming a mold having a thickness of several millimeters. The thing of about -7000 mPa * s is preferable, Furthermore, the thing of about 2000-5000 mPa * s is more preferable.
[0035]
The surface energy of the mold is preferably in the range of 10 dyn / cm to 30 dyn / cm, and preferably in the range of 15 dyn / cm to 24 dyn / cm from the viewpoint of adhesion to the base film.
The share rubber hardness of the mold is 15 to 80, preferably 20 to 60, from the viewpoint of mold taking performance, maintaining the shape of the recess, and peelability.
The surface roughness (root mean square roughness (RMS)) of the mold is preferably 0.2 μm or less, and preferably 0.1 μm or less from the viewpoint of mold-taking performance.
The template is preferably light transmissive in the ultraviolet region and / or visible region. The mold is preferably light transmissive in the visible region when positioning the mold in close contact with the clad film substrate in the following step 2), and in the following 3) step. This is because it can be observed that the core-forming curable resin is filled in the mold recess, and the completion of filling can be easily confirmed. In addition, it is preferable that the mold is light transmissive in the ultraviolet region because, when an ultraviolet curable resin is used as the core-forming curable resin, ultraviolet curing is performed through the mold. The transmittance in the ultraviolet region (250 nm to 400 nm) is preferably 80% or more.
[0036]
Liquid silicone rubber, which becomes a silicone rubber after curing, is excellent in the conflicting properties of adhesion to the clad film substrate and peelability, and has the ability to copy nanostructures. Silicone rubber and cladding When the base material is in close contact, liquid can be prevented from entering. Such a mold using silicone rubber copies the master with high accuracy and adheres well to the clad substrate, so that only the recess between the mold and the clad substrate is efficiently filled with the core forming resin. In addition, the clad substrate and the mold can be easily peeled off. Therefore, a polymer optical waveguide whose shape is maintained with high accuracy can be produced very simply from this mold.
[0037]
2) The process of adhering the flexible film substrate for clad with good adhesion to the mold to the mold
Since the optical element produced from the polymer optical waveguide of the present invention is used for optical wiring at various levels, the material of the flexible film base material for clad depends on the refractive index and light transmission depending on the use of the optical element. It is selected in consideration of optical characteristics such as properties, mechanical strength, heat resistance, adhesion to a mold, flexibility, and the like. Examples of the film include an alicyclic acrylic resin film, an alicyclic olefin resin film, a cellulose triacetate film, and a fluorine-containing resin film. In order to secure a difference in refractive index from the core, the refractive index of the film substrate is preferably smaller than 1.55, preferably smaller than 1.53.
[0038]
As the alicyclic acrylic resin film, OZ-1000, OZ-1100 (manufactured by Hitachi Chemical Co., Ltd.) or the like in which an aliphatic cyclic hydrocarbon such as tricyclodecane is introduced into an ester substituent is used.
As the alicyclic olefin resin film, those having a norbornene structure in the main chain, and those having a norbornene structure in the main chain and an alkyloxycarbonyl group (the alkyl group having 1 to 6 carbon atoms as the alkyl group) And those having a polar group such as an alkyl group). Among them, the alicyclic olefin resin having a norbornene structure in the main chain and a polar group such as an alkyloxycarbonyl group in the side chain as described above has a low refractive index (refractive index is around 1.50, core clad In particular, the optical waveguide sheet of the present invention is produced because it has excellent optical characteristics such as a high refractive index, excellent adhesive properties with a mold, and excellent heat resistance. Suitable for
The thickness of the film substrate is appropriately selected in consideration of flexibility, rigidity, ease of handling, etc., and is generally preferably about 0.1 mm to 0.5 mm.
[0039]
3) A core-forming curable resin is filled into a through-hole at one end of a mold recess to which a clad film base is in close contact, and the core is formed by vacuum suction from the through-hole at the other end of the mold recess. Filling the concave portion of the mold with a curable resin
In this step, the core-forming curable resin is filled into the through-hole provided on the resin entrance portion side, and is sucked under reduced pressure from the through-hole provided on the resin discharge portion side, and the mold and the clad film The gap formed between the substrate and the substrate (the concave portion of the mold) is filled. By sucking under reduced pressure, the adhesion between the mold and the film substrate for clad is improved, and mixing of bubbles can be avoided. The vacuum suction is performed, for example, by inserting a suction tube into a through hole provided on the discharge portion side and connecting the suction tube to a pump.
As the core-forming curable resin, resins such as radiation curable, electron beam curable, and thermosetting can be used, and among them, an ultraviolet curable resin and a thermosetting resin are preferably used.
As the ultraviolet curable resin or thermosetting resin for forming the core, an ultraviolet curable or thermosetting monomer, an oligomer, or a mixture of a monomer and an oligomer is preferably used.
In addition, an epoxy-based, polyimide-based, or acrylic-based ultraviolet curable resin is preferably used as the ultraviolet curable resin.
[0040]
Since the core-forming curable resin fills the gaps (mold recesses) formed between the mold and the film substrate by capillarity, the core-forming curable resin used is sufficient to make it possible. It must be low viscosity. Therefore, the viscosity of the curable resin is preferably 10 mPa · s to 2000 mPa · s, desirably 20 mPa · s to 1000 mPa · s, more preferably 30 mPa · s to 500 mPa · s.
In addition, in order to accurately reproduce the original shape of the convex portion corresponding to the optical waveguide core formed on the master, it is necessary that the volume change before and after curing of the curable resin is small. For example, a reduction in volume causes waveguide loss. Therefore, the core-forming curable resin desirably has a volume change as small as possible, and is desirably 10% or less, preferably 6% or less. Lowering the viscosity using a solvent is preferably avoided if possible because the volume change before and after curing is large.
[0041]
In order to reduce the volume change (shrinkage) after curing of the core-forming curable resin, a polymer can be added to the resin. The polymer preferably has compatibility with the core-forming curable resin and does not adversely affect the refractive index, elastic modulus, and transmission characteristics of the resin. In addition to reducing the volume change by adding a polymer, the viscosity and the glass transition point of the cured resin can be highly controlled. Examples of the polymer include, but are not limited to, acrylic, methacrylic acid, and epoxy polymers.
[0042]
The refractive index of the cured product of the core-forming curable resin needs to be larger than that of the film base material (including the clad layer in the step 5 below) to be the clad, and is 1.50 or more, preferably 1. 53 or more. The difference in refractive index between the clad (including the clad layer in the following 5) and the core is 0.01 or more, preferably 0.03 or more.
[0043]
4) Step of curing the filled core-forming curable resin and peeling the mold from the clad film substrate
In this step, the filled core-forming curable resin is cured. To cure the ultraviolet curable resin, an ultraviolet lamp, an ultraviolet LED, a UV irradiation device or the like is used. To cure the thermosetting resin, heating in an oven or the like is used.
Further, the mold used in the steps 1) to 3) can be used as it is for the cladding layer as long as the conditions such as the refractive index are satisfied. In this case, the mold does not need to be peeled off and is used as it is as the cladding layer. be able to. In this case, the mold is preferably subjected to ozone treatment in order to improve the adhesion between the mold and the core material.
[0044]
5) A step of forming a clad layer on the clad film substrate on which the core is formed.
A clad layer is formed on the film base material on which the core is formed. As the clad layer, a film base material (for example, a clad film base material used in the step 2) is used) Examples thereof include a layer obtained by applying and curing a curable resin, and a polymer film obtained by applying and drying a solvent solution of a polymer material. As the curable resin for cladding, an ultraviolet curable resin or a thermosetting resin is preferably used. For example, an ultraviolet curable or thermosetting monomer, an oligomer, or a mixture of a monomer and an oligomer is used.
In order to reduce the volume change (shrinkage) after curing of the curable resin for cladding, a polymer (for example, methacrylic acid) that is compatible with the resin and does not adversely affect the refractive index, elastic modulus, and transmission characteristics of the resin. Acid-based and epoxy-based) can be added to the resin.
[0045]
When a film is used as the clad layer, it is bonded using an adhesive. At this time, it is desirable that the refractive index of the adhesive is close to the refractive index of the film. As the adhesive to be used, an ultraviolet curable resin or a thermosetting resin is preferably used. For example, an ultraviolet curable or thermosetting monomer, an oligomer, or a mixture of a monomer and an oligomer is used.
In order to reduce the volume change (shrinkage) after curing of the ultraviolet curable resin or the thermosetting resin, a polymer similar to the polymer added to the cladding layer can be added.
The refractive index of the cladding layer is 1.55 or less, preferably 1.53 or less in order to ensure a difference in refractive index from the core. In addition, it is preferable from the viewpoint of light confinement that the refractive index of the cladding layer be the same as the refractive index of the film substrate.
[0046]
Next, an example of a method for producing a polymer optical waveguide of the present invention will be described with reference to the drawings.
FIG. 3A shows a cut surface obtained by cutting the master 10 on which the convex portion 12 corresponding to the optical waveguide core is formed at a right angle to the longitudinal direction of the convex portion 12. First, as shown in FIG. 3B, a layer of a mold-forming curable resin is formed on the surface of the master 10 on which the convex portions 12 are formed by coating, and then cured to form a cured layer 20a. FIG. 3 (B) shows a cut surface obtained by cutting the hard disk 20a formed on the master disk at a right angle to the longitudinal direction of the convex portion 12. FIG. Next, the hardened layer 20a is peeled from the master 10 (molding), and then two through holes are provided so that both ends of the concave portion 22 corresponding to the convex portion formed in the mold are exposed (not shown). ) Prepare the mold 20. FIG. 3C shows a surface obtained by cutting the mold 20 so that a surface cut at right angles to the longitudinal direction of the concave portion 22 appears.
The clad film substrate 30 having good adhesion to the mold is brought into close contact with the mold thus produced. FIG. 3D shows a surface obtained by cutting a mold and a film in close contact so that a surface cut at right angles to the longitudinal direction of the mold recess 22 appears. Next, one of the through holes (not shown) of the mold is filled with the core-forming curable resin 40a, and the resin is sucked into the concave portion 22 of the mold by using a capillary phenomenon by sucking under pressure from another through hole (not shown). Fill. FIG. 3E shows a surface cut so that a cut surface perpendicular to the longitudinal direction of the mold recess 22 appears in the state where the recess of the mold is filled with the core-forming curable resin 40a. Thereafter, the curable resin in the recess is cured, and the mold is peeled off (not shown). FIG. 3F shows a cut surface obtained by cutting an optical waveguide core 40 formed on a clad film base material at a right angle to the longitudinal direction of the core.
Further, the polymer optical waveguide sheet 60 of the present invention is produced by forming the clad layer 50 on the core forming surface of the clad film substrate. FIG. 3G shows a cut surface obtained by cutting the polymer optical waveguide sheet 60 perpendicularly to the longitudinal direction of the core.
[0047]
FIG. 4 shows an example in which a film serving as a clad is bonded to a film base material on which a core is formed by an adhesive. 4 (A) to 4 (F) are the same as the steps shown in FIGS. 3 (A) to 3 (F), and start from the master and form the core on the film substrate. The process is shown. FIG. 4G shows a polymer optical waveguide sheet 60 obtained by bonding a film 52 to be a clad with an adhesive 54 on the core forming surface of a film base material, cut at right angles to the longitudinal direction of the core. The cut surface is shown.
[0048]
In the method for producing a polymer optical waveguide of the present invention, in particular, a liquid silicone rubber that is cured as a curable resin for forming a mold and becomes a rubbery state, particularly a liquid dimethylsiloxane rubber, and a norbornene in the main chain as a film substrate for cladding. The combination using an alicyclic olefin resin having a structure and having a polar group such as an alkyloxycarbonyl group in the side chain has particularly high adhesion between the two, and there is no deformation of the mold recess structure, and the recess structure Even when the cross-sectional area is extremely small (for example, a rectangle of 10 × 10 μm), the concave portion can be quickly filled with the curable resin by the capillary phenomenon.
[0049]
The polymer optical waveguide produced by the method for producing a polymer optical waveguide as described above is obtained as a sheet having flexibility (flexible polymer optical waveguide sheet).
[0050]
[Method for Manufacturing Optical Element]
The method for producing an optical element of the present invention comprises a core end portion of a flexible polymer optical waveguide sheet (hereinafter sometimes referred to as “optical waveguide sheet”) which is a polymer optical waveguide produced as described above. After the core end face having an optical mirror surface is formed by cutting, the light emitting part is attached. Moreover, after attaching the light emitting part, an optical connector can be further connected.
In order to cut the core end, it is preferable to use a dicing saw. When the light emitting unit is directly connected to the core end surface of the optical waveguide sheet, the core is cut so that the core end surface is 90 ° with respect to the core longitudinal direction. Further, the core is cut so that the end surface of the core is 45 ° with respect to the longitudinal direction of the core to form a mirror surface, and the light emitting unit is placed on the upper end of the clad film base or the plane of the clad layer. The light from can be guided to the core by the mirror surface. In this case, the core diameter is substantially required to be about 50 μm in consideration of the spread angle of the light emitting part. The 45 ° mirror can be formed only by cutting with a dicing saw using a blade having an angle of 45 °, and a 45 ° mirror using total reflection of light is formed.
FIG. 5 is a conceptual diagram illustrating an example of an optical element. In the optical element 100, the end surface of the core 40 of the polymer optical waveguide is cut at 45 ° with a dicing saw to form a mirror surface 42, and light (shown by an arrow) from the light emitting portion is incident on the mirror surface and reflected. The light emitting unit 70 is disposed on the cladding layer 50 so as to be introduced into the core. Reference numeral 80 denotes an optical connector.
[0051]
The light emitting unit preferably uses a surface emitting laser array (VCSEL array) in order to increase the degree of integration of the integrated circuit.
Since the semiconductor laser element of the surface emitting laser array generates heat, it is necessary to radiate heat while keeping a space between the semiconductor laser element and the core end face in order to prevent adverse effects due to the heat generation, but the semiconductor laser beam has a spread angle. Therefore, if the interval exceeds a certain limit, the laser beam spot diameter on the core end face is larger than the core allows (for example, when the core diameter is 50 μm, the allowable diameter is 45 μm).
However, by taking into account the spot diameter of the semiconductor laser in the surface emitting laser array and the spread angle of the laser beam, the distance between the semiconductor laser and the end face of the core is sufficiently avoided from the influence of heat generation without providing the lens or the like. It will be possible to leave as much as possible.
[0052]
For example, a surface-emitting laser array (Fuji Xerox Co., Ltd., VCSEL-AM-0104) having a semiconductor laser spot diameter of 10 μm, a beam divergence angle of 25 °, and an array interval of 250 μm, a multimode optical waveguide with a core diameter of 50 μm. When attached to the end face of the sheet, the laser beam spot diameter on the core surface is allowed to be about 45 μm, so that the distance between the semiconductor laser and the core end face can be up to 79 μm. When the diameter of the laser beam at the core end face is set to 30 μm, the distance between the semiconductor laser and the core end face is about 45 μm. If this gap is present, the temperature of the semiconductor laser element rises to about 100 ° C. Even if this is taken into consideration, sufficient heat can be released.
Therefore, the surface emitting laser array preferably has a semiconductor laser spot diameter of 1 to 20 μm, a laser beam spread angle of about 5 ° to 30 °, and an array interval of about 100 to 500 μm. For example, Fuji Xerox Co., Ltd. VCSEL-AM-0104, VCSEL-AM-0112, etc. are preferably used.
[0053]
Further, as a means for maintaining the distance between the core end surface of the optical waveguide sheet and the semiconductor laser of the surface emitting laser array as described above, a frame having a height sufficient to maintain the distance is provided on the surface emitting laser array. The frame and the optical waveguide sheet may be attached using an adhesive or the like.
[0054]
In addition, it is better to connect an optical connector to the optical element of the present invention. The optical connector is preferably compatible with a fiber array connector such as an MT connector in order to facilitate connection with an optical fiber.
[0055]
The method for producing an optical element of the present invention is simply a surface emitting laser (or an optical connector) attached to the core end portion or the clad surface end portion of the optical waveguide sheet produced as described above. This is a simple method and can achieve a low cost that is not comparable to a conventional method of manufacturing an optical element.
[0056]
  Made by the above manufacturing methodThe optical element includes a clad made of a flexible film substrate, a core made of a cured product of a core-forming curable resin provided on the clad, and a clad layer formed so as to cover the core. In the molecular optical waveguide sheet, a light emitting part is attached on the core end face or the clad face end, and an optical connector is further provided.
  SaidThe optical element is extremely simplified as an element because an optical path changing element such as a lens or a mirror is unnecessary. Also,SaidThe optical element uses a flexible polymer optical waveguide sheet, and a light emitting part is provided at the end of the core or clad surface, so the entire element is highly flexible and can be easily bent and deformed. In addition, it can be incorporated in an integrated circuit in a deformed state, and in combination with the simplified element, the degree of integration of the integrated circuit can be greatly increased.
  SaidThe optical element can be used for a wide range of applications such as optical wiring in various layers, for example, optical wiring between equipment devices, between boards in equipment devices, and between chips in boards.
  In FIG.SaidAnother example of the optical element is shown as a conceptual diagram (perspective view). In FIG. 6, 110 is an optical element, 120 is a lower clad (flexible film base material for clad), 140 is a core, 160 is an upper clad (cladding layer), and 170 is a light emitting portion (for example, 1 × 4 VCSEL Array). Reference numerals 180 and 180 denote light receiving portions (for example, 1 × 4 Photo Diode Array). Reference numeral 190 denotes an optical connector (for example, an MT connector).
[0057]
【Example】
EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to these examples.
Example 1
A thick film resist (SU-8, manufactured by Micro Chemical Co., Ltd.) is applied to the Si substrate by spin coating, then pre-baked at 80 ° C., exposed through a photomask, developed, and square with four cross sections. Convex portions (width: 50 μm, height: 50 μm, length: 80 mm) were formed. The interval between the protrusions was 250 μm. Next, this was post-baked at 120 ° C. to prepare a master for preparing a polymer optical waveguide.
Next, after applying a release agent to this master, a thermosetting liquid dimethylsiloxane rubber (manufactured by Dow Corning Asia Co., Ltd .: SYLGARD 184, viscosity 5000 mPa.s) and a mixture of the curing agent are poured, and 120 ° C. After being cured by heating for 30 minutes, the mold was peeled off to produce a mold having a concave portion corresponding to a rectangular convex portion (mold thickness: 5 mm).
Further, as shown in FIG. 1, a through hole having a circular planar shape and a tapered cross-sectional shape in the mold thickness direction is formed by punching so as to communicate with the recess at one end and the other end of the recess. Was made. The through hole on the side where the curable resin for forming the core of the mold enters is 4 mm in diameter on the surface where the mold is in contact with the clad film substrate, and 3.5 mm in the surface on the opposite side of the mold. Moreover, the through-hole for decompression suction was formed so that the size was the same as the through-hole on the entry side, and the taper was reversed.
The mold had a surface energy of 22 dyn / cm, a shear rubber hardness of 60, a surface roughness of 10 nm or less, an ultraviolet transmittance of 80% or more, and was transparent and well observed.
[0058]
The mold and a clad film base material (Arton Film, manufactured by JSR Corporation, refractive index 1.510) having a film thickness of 188 μm, which is slightly larger than the mold, were brought into close contact with each other. Next, a few drops of UV curable resin (manufactured by JSR: PJ3001) having a viscosity of 1300 mPa · s are dropped into the mold entrance side through hole and sucked under reduced pressure from the discharge side (vacuum suction side) through hole. 20 minutes The recess was filled with an ultraviolet curable resin. Then 50mW / cm²The UV light was irradiated from the upper part of the mold for 5 minutes to be cured by ultraviolet rays. When the mold was peeled off from the arton film, a core having the same shape as that of the master disc protrusion was formed on the arton film. The refractive index of the core was 1.591.
Next, an UV curable resin (manufactured by JSR Co., Ltd.) having a refractive index after curing of 1.510, which is the same as that of ARTON film, is applied to the entire surface of the core of ARTON film, and then 50 mW / cm.²Were cured by UV irradiation for 5 minutes (film thickness after curing: 10 μm). A flexible optical waveguide sheet (50 mm × 300 mm) was obtained.
Next, using a dicing saw equipped with a blade for Si, the optical waveguide sheet was cut at a right angle to the longitudinal direction of the core to expose the core having a mirror surface, thereby forming a light input / output unit. The loss of this polymer optical waveguide was 0.33 dB / cm.
Next, a 1 × 4 surface emitting laser array (manufactured by Fuji Xerox: VCSEL-AM-0104, semiconductor laser spot diameter of 10 μm, beam divergence angle of 25 °, arrayed on the core end face of the optical waveguide sheet produced as described above A flexible optical element with a surface emitting laser array was obtained by attaching a gap of 250 μm) with a gap of 50 μm.
[0059]
Example 2
A master for producing a polymer optical waveguide having four convex portions (width: 50 μm, height: 50 μm, length: 80 mm) having a square cross section was produced by the same method as in Example 1.
Next, after a mold was made by the same method as in Example 1, two through holes having the same taper as in Example 1 were provided to form a mold.
This mold and an Arton film (film thickness 188 μm) that is slightly larger than the mold are brought into close contact with each other, and a few drops of a thermosetting resin (manufactured by JSR Co., Ltd.) having a viscosity of 500 mPa · s is dropped into one through hole of the mold. When sucked from the other through hole, the concave portion was filled with the thermosetting resin in 5 minutes. This was heat-cured by heating in an oven at 130 ° C. for 30 minutes. When the mold was peeled off from the arton film, a core having the same shape as that of the master disc protrusion was formed on the arton film. The refractive index of the core was 1.570.
Furthermore, a 1.510 thermosetting resin (made by JSR Co., Ltd.) having the same refractive index as that of Arton Film was applied on the entire surface of the core forming surface of ARTON film, and then heat-cured (cured film). 10 μm thick). A flexible optical waveguide sheet (50 mm × 300 mm) was obtained.
Next, using a dicing saw equipped with a blade for Si, the optical waveguide sheet was cut at a right angle to the longitudinal direction of the core to expose the core having a mirror surface, thereby forming a light input / output unit. The loss of this polymer optical waveguide was 0.33 dB / cm.
Next, a 1 × 4 surface emitting laser array (manufactured by Fuji Xerox: VCSEL-AM-0104) is attached to the core end face of the optical waveguide sheet produced as described above with a 50 μm gap, and a surface emitting laser array is attached. A flexible optical element was obtained.
[0060]
Example 3
The process up to the step of forming the core on the arton film in Example 1 was carried out by the same method. Next, Arton film (film thickness: 188 μm) was bonded to the core forming surface of Arton film using an adhesive having a refractive index of 1.510 (manufactured by JSR Co., Ltd.) to produce a flexible optical waveguide sheet.
Next, using a dicing saw equipped with a blade for Si, the optical waveguide sheet was cut at a right angle to the longitudinal direction of the core to expose the core having a mirror surface, thereby forming a light input / output unit. The loss of this polymer optical waveguide was 0.33 dB / cm.
Next, a 1 × 4 surface emitting laser array (manufactured by Fuji Xerox: VCSEL-AM-0104) is attached to the core end face of the optical waveguide sheet (50 mm × 300 mm) produced as described above, with a gap of 50 μm, A flexible optical element with a surface emitting laser array was obtained.
[0061]
Example 4
The process up to the step of forming the core on the arton film in Example 3 was carried out by the same method except that the core diameter was 100 μm. Next, arton film (film thickness 100 μm) was bonded to the core forming surface of arton film using an adhesive having a refractive index of 1.510 (manufactured by JSR Co., Ltd.) to prepare a flexible optical waveguide sheet.
Next, this optical waveguide sheet is cut at 45 ° with respect to the longitudinal direction of the core using a dicing saw equipped with a 45 ° angled Si blade to expose the core having a 45 ° mirror surface. I / O section.
Next, a 1 × 4 surface emitting laser array (manufactured by Fuji Xerox: VCSEL-AM-0104) is attached in close contact with the Arton film surface which is the cladding layer of the optical waveguide sheet (50 mm × 300 mm) produced as described above. And a flexible optical element with a surface emitting laser array.
[0062]
【The invention's effect】
  The method for producing a polymer optical waveguide according to the present invention makes it possible to produce a polymer optical waveguide easily by simplifying the production process. Compared with the conventional method for producing a polymer optical waveguide, the production method is extremely low and expensive. A molecular optical waveguide can be produced, and a through hole is provided in the mold, and the core forming curable resin discharge side of the mold recess is sucked under reduced pressure, so that the adhesion between the mold and the film substrate is improved, and air bubbles Can be avoided. Therefore, the polymer optical waveguide produced by the manufacturing method of the present invention is a flexible polymer optical waveguide that has high loss and little loss loss and can be freely loaded into various devices. In addition, the shape of the polymer optical waveguide can be freely set.
  In addition, the method for producing an optical element of the present invention simply attaches a surface emitting laser (or optical connector) to the core end portion or the clad surface end portion of the polymer optical waveguide (optical waveguide sheet) produced as described above. Therefore, it is a very simple method as a whole, and it is possible to achieve a cost that is incomparable with conventional optical element manufacturing methods.The
[Brief description of the drawings]
FIG. 1 is a conceptual diagram showing an example of a mold used in the present invention, FIG. 1 (A) is a plan view thereof, and FIG. 1 (B) is a sectional view thereof.
FIG. 2 is a perspective view showing an example of a master used for producing a mold.
FIG. 3 is a conceptual diagram showing a production process of the polymer optical waveguide of the present invention.
FIG. 4 is a conceptual diagram showing another manufacturing process of the polymer optical waveguide of the present invention.
FIG. 5 is a conceptual diagram showing a cross section of an optical element in which a core end face of a polymer optical waveguide of the present invention is cut and a light emitting portion and an optical connector are attached.
FIG. 6 of the present inventionMade by manufacturing methodIt is a conceptual diagram which shows another example of an optical element.
[Explanation of symbols]
10 Master disc
20a Hardened layer of curable resin for mold formation
20 Mold
22 Mold recess
26 Entry side through hole
28 Discharge side through hole
30 Flexible film base material for clad
40a Curable resin for core
40 cores
50 Clad layer
52 Clad film
54 Adhesive
70 Light emitting part
80 optical connector
100, 110 Optical element
120 Flexible film base material for clad
140 cores
160 Clad layer
170 Light emitter
190 Optical connector

Claims (19)

1) is formed from a cured layer of mold-forming curable resin, and a plurality of recesses corresponding to the optical waveguide core protrusion, the through hole for the liquid reservoir communicating in common to one end of the plurality of recesses and A mold having two or more through-holes for vacuum suction that communicate in common with the other end, wherein the through-hole for the reservoir and the through-hole for vacuum suction are formed in a recess of the mold. A step of preparing a mold, which is a hole penetrating the surface and the surface opposite to the surface, 2) a step of closely adhering a flexible film base material for clad with the mold to the mold, 3 ) Filling the through hole at one end of the concave portion of the mold with the flexible film base material for clad closely attached, and sucking under reduced pressure from the through hole at the other end of the concave portion of the mold. And filling the recess of the mold with the core-forming curable resin 4) A step of curing the filled core-forming curable resin and peeling the mold from the clad flexible film substrate; and 5) forming a clad layer on the clad flexible film substrate on which the core is formed. A process for producing a polymer optical waveguide comprising the steps.   The method for producing a polymer optical waveguide according to claim 1, wherein after the step (5), a step of forming a core surface having an optical mirror surface by cutting the end portion of the core is performed.   The through hole for the liquid reservoir has a cross-sectional area that is larger on a side in contact with the clad flexible film substrate and becomes smaller as the clad flexible film substrate is separated from the clad flexible film substrate. The manufacturing method of the polymer optical waveguide of description.   The method for producing a polymer optical waveguide according to claim 1, wherein the clad flexible film substrate has a refractive index of 1.55 or less.   The method for producing a polymer optical waveguide according to claim 1, wherein the clad flexible film base material is an alicyclic olefin resin film.   6. The method for producing a polymer optical waveguide according to claim 5, wherein the alicyclic olefin resin film is a resin film having a norbornene structure in the main chain and a polar group in the side chain.   2. The method for producing a polymer optical waveguide according to claim 1, wherein in the step 2), the clad flexible film substrate is held by a rigid body having high flatness.   The method for producing a polymer optical waveguide according to claim 1, wherein the mold-forming curable resin is a liquid silicone rubber.   The method for producing a polymer optical waveguide according to claim 1, wherein the surface energy of the mold is 10 dyn / cm to 30 dyn / cm.   The method of manufacturing a polymer optical waveguide according to claim 1, wherein the mold has a Share rubber hardness of 15 to 80.   2. The method for producing a polymer optical waveguide according to claim 1, wherein the mold has a surface roughness of 0.1 [mu] m or less.   The method for producing a polymer optical waveguide according to claim 1, wherein the template is light transmissive in an ultraviolet region and / or a visible region.   The method for producing a polymer optical waveguide according to claim 1, wherein the clad layer is formed by applying a curable resin for clad and then curing the clad layer.   2. The method of manufacturing a polymer optical waveguide according to claim 1, wherein the clad layer is formed by laminating a clad film with an adhesive having a refractive index close to that of the film. 1) is formed from a cured layer of mold-forming curable resin, and a plurality of recesses corresponding to the optical waveguide core protrusion, the through hole for the liquid reservoir communicating in common to one end of the plurality of recesses and A mold having two or more through-holes for vacuum suction that communicate in common with the other end, wherein the through-hole for the reservoir and the through-hole for vacuum suction are formed in a recess of the mold. A step of preparing a mold, which is a hole penetrating the surface and the surface opposite to the surface, 2) a step of closely adhering a flexible film base material for clad with the mold to the mold, 3 ) Filling the through hole at one end of the concave portion of the mold with the flexible film base material for clad closely attached, and sucking under reduced pressure from the through hole at the other end of the concave portion of the mold. And filling the recess of the mold with the core-forming curable resin 4) Curing the Hama cores forming curable resin, producing a polymer optical waveguide having a. 1) is formed from a cured layer of mold-forming curable resin, and a plurality of recesses corresponding to the optical waveguide core protrusion, the through hole for the liquid reservoir communicating in common to one end of the plurality of recesses and A mold having two or more through-holes for vacuum suction that communicate in common with the other end, wherein the through-hole for the reservoir and the through-hole for vacuum suction are formed in a recess of the mold. A step of preparing a mold, which is a hole penetrating the surface and the surface opposite to the surface, 2) a step of closely adhering a flexible film base material for clad with the mold to the mold, 3 ) Filling the through hole at one end of the concave portion of the mold with the flexible film base material for clad closely attached, and sucking under reduced pressure from the through hole at the other end of the concave portion of the mold. And filling the recess of the mold with the core-forming curable resin 4) A step of curing the filled core-forming curable resin and peeling the mold from the clad flexible film substrate; and 5) forming a clad layer on the clad flexible film substrate on which the core is formed. A method for manufacturing an optical element, comprising: a step, 6) a step of cutting a core to form a core end surface having an optical mirror surface, and 7) a step of attaching a light emitting part.   The method of manufacturing an optical element according to claim 16, wherein the core end surface is cut at 90 ° with respect to the longitudinal direction of the core, and the light emitting portion is directly connected to the core end surface.   17. The method of manufacturing an optical element according to claim 16, wherein the core end surface is cut at 45 degrees with respect to the longitudinal direction of the core to form a mirror surface, and light from the light emitting portion is guided to the core by the mirror surface.   The method of manufacturing an optical element according to claim 16, further comprising a step of attaching an optical connector after the step (7).

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