Patent Publication Number: US-2007114684-A1

Title: Optical waveguide and optical waveguide manufacturing method

Description:
CROSS-REFERENCE TO RELATED APPLICATION  
      This application claims priority under 35USC119 from Japanese Patent Applications No. 2005-336283 and No. 2005-336284, the disclosures of which are incorporated by reference herein.  
     BACKGROUND  
      1. Technical Field  
      The present invention relates to a method of manufacturing an optical waveguide for guiding light to be utilized for a mobile device or the like as waveguide light, and an optical waveguide manufactured by this method.  
      2. Related Art  
      There are methods, in which resins are laminated and resin layers are processed, for manufacturing an optical waveguide.  
      According to these methods, high-performance optical waveguides can be manufactured easily.  
      According to this manufacturing method, however, the polymer resin to be the cladding layer is applied to the substrate, and the polymer resin to be the core layer is applied to the cladding layer so that a double-layered resin layer is formed.  
      For this reason, the substrate which does not function as the optical waveguide is necessary at the manufacturing steps, and thus the manufactured waveguide is an expensive product.  
      In the case where a power supply to a mobile device or the like is necessary, an electric conductive line is necessary independently from the optical waveguide.  
     SUMMARY  
      The present invention has been made in view of the above circumstances and provides an optical waveguide and an optical waveguide manufacturing method.  
      According to an aspect of the present invention, an optical waveguide manufacturing method is provided. The optical wave guide manufacturing method includes: (a) preparing a polymer film, applying polymer resin with refractive index different from the polymer film to the polymer film and curing the resin, so as to manufacture a double-layered polymer film having a cladding layer and a core layer with refractive index higher than the cladding layer; (b) cutting the core layer using a dicing saw with a blade for enabling cutting of the resin layer so as to process the core layer into core portions of an optical waveguide; and (c) filling concave portions of the cut core layer with polymer resin with the same refractive index as the cladding layer, covering the core portions with the polymer resin, and curing the polymer resin so as to form a cladding resin layer. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
      Embodiments of the present invention will be described in detail based on the following figures, wherein:  
       FIG. 1A  is a conceptual diagram illustrating the step of manufacturing a double-layered polymer film in a manufacturing method according to a first exemplary embodiment of the present invention;  
       FIG. 1B  is a conceptual diagram illustrating the step of processing the double-layered polymer film using a dicing saw in the manufacturing method according to the first exemplary embodiment of the present invention;  
       FIG. 1C  is a conceptual diagram illustrating the step of applying resin to the double-layered polymer film processed by the dicing saw in the manufacturing method according to the first exemplary embodiment of the present invention;  
       FIG. 1D  is a conceptual diagram illustrating the step of irradiating the resin applied to the double-layered polymer film with an UV ray in the manufacturing method according to the first exemplary embodiment of the present invention;  
       FIG. 2  is a perspective view of a multi-blade to be used in the manufacturing method according to the first exemplary embodiment and a second exemplary embodiment of the present invention;  
       FIG. 3A  is a conceptual diagram illustrating the step of manufacturing a triple-layered polymer film in the manufacturing method according to the second exemplary embodiment of the present invention;  
       FIG. 3B  is a conceptual diagram illustrating the step of processing the triple-layered polymer film using a dicing saw in the manufacturing method according to the second exemplary embodiment of the present invention;  
       FIG. 3C  is a conceptual diagram illustrating the step of applying resin to the triple-layered polymer film processed by the dicing saw in the manufacturing method according to the second exemplary embodiment of the present invention;  
       FIG. 3D  is a conceptual diagram illustrating the step of irradiating the resin applied to the triple-layered polymer film with a UV ray in the manufacturing method according to the second exemplary embodiment of the present invention;  
       FIG. 4A  is a conceptual diagram illustrating the step of manufacturing a double-layered polymer film in the manufacturing method according to a third exemplary embodiment of the present invention;  
       FIG. 4B  is a conceptual diagram illustrating the step of processing the double-layered polymer film with a dicing saw in the manufacturing method according to the third exemplary embodiment of the present invention;  
       FIG. 4C  is a conceptual diagram illustrating the step of arranging an electric conductive line in the manufacturing method according to the third exemplary embodiment of the present invention;  
       FIG. 4D  is a conceptual diagram illustrating the step of applying resin to the double-layered polymer film processed by the dicing saw in the manufacturing method according to the third exemplary embodiment of the present invention;  
       FIG. 4E  is a conceptual diagram illustrating the step of irradiating the resin applied to the double-layered polymer film with an UV ray in the manufacturing method according to the third exemplary embodiment of the present invention;  
       FIG. 5  is a perspective view of a multi-blade to be used in the manufacturing method according to the third exemplary embodiment of the present invention;  
       FIG. 6A  is a conceptual diagram illustrating the step of manufacturing the double-layered polymer film in the manufacturing method according to a fourth exemplary embodiment of the present invention;  
       FIG. 6B  is a conceptual diagram illustrating the step of processing the double-layered polymer film using a dicing saw in the manufacturing method according to the fourth exemplary embodiment of the present invention;  
       FIG. 6C  is a conceptual diagram illustrating the step of applying resin to the double-layered polymer film processed by the dicing saw in the manufacturing method according to the fourth exemplary embodiment of the present invention;  
       FIG. 6D  is a conceptual diagram illustrating the step of laminating a polymer film with electric conductive line in the manufacturing method according to the fourth exemplary embodiment of the present invention;  
       FIG. 6E  is a conceptual diagram illustrating the step of irradiating the resin applied to the double-layered polymer film with an UV ray in the manufacturing method according to the fourth exemplary embodiment of the present invention;  
       FIG. 7  is a sectional view of the polymer film with electric conductive line to be used in the manufacturing method according to the fourth exemplary embodiment of the present invention;  
       FIG. 8  is a plan view of an optical waveguide manufactured by the manufacturing method according to the fourth exemplary embodiment of the present invention;  
       FIG. 9A  is a conceptual diagram illustrating the step of manufacturing a triple-layered polymer film in the manufacturing method according to a fifth exemplary embodiment of the present invention;  
       FIG. 9B  is a conceptual diagram illustrating the step of processing the triple-layered polymer film using a dicing saw in the manufacturing method according to the fifth exemplary embodiment of the present invention;  
       FIG. 9C  is a conceptual diagram illustrating the step of arranging electric conductive lines in the manufacturing method according to the fifth exemplary embodiment of the present invention;  
       FIG. 9D  is a conceptual diagram illustrating the step of applying resin to the triple-layered polymer film processed by the dicing saw in the manufacturing method according to the fifth exemplary embodiment of the present invention;  
       FIG. 9E  is a conceptual diagram illustrating the step of irradiating the resin applied to the triple-layered polymer film with an UV ray in the manufacturing method according to the fifth exemplary embodiment of the present invention;  
       FIG. 10A  is a conceptual diagram illustrating the step of manufacturing the triple-layered polymer film in the manufacturing method according to a sixth exemplary embodiment of the present invention;  
       FIG. 10B  is a conceptual diagram illustrating the step of processing the triple-layered polymer film using a dicing saw in the manufacturing method according to the sixth exemplary embodiment of the present invention;  
       FIG. 10C  is a conceptual diagram illustrating the step of applying resin to the triple-layered polymer film processed by the dicing saw in the manufacturing method according to the sixth exemplary embodiment of the present invention;  
       FIG. 10D  is a conceptual diagram illustrating the step of laminating a polymer film with electric conductive line in the manufacturing method according to the sixth exemplary embodiment of the present invention; and  
       FIG. 10E  is a conceptual diagram illustrating the step of irradiating the resin applied to the triple-layered polymer film with an UV ray in the manufacturing method according to the sixth exemplary embodiment of the present invention. 
    
    
     DETAILED DESCRIPTION  
      A manufacturing method for an optical waveguide according to a first embodiment of the present invention is explained below following the order of the steps with reference to  FIGS. 1A  to  2 .  
      As shown in  FIG. 1A , a plurality of adsorption ports  11  are formed on the surface of a fixing table  10 , and a suction power is generated by a vacuum pump. A polymer film  12  to be a cladding layer is adsorbed and stuck to the fixing table  10 , and ultraviolet curing polymer resin with high refractive index is applied uniformly (spin-coating) to the polymer film  12 . The polymer resin is irradiated with an UV ray by an UV ray irradiation device so as to be cured, and a core layer  14  and the polymer film  12  are formed so that a double-layered polymer film  18  is manufactured.  
      For example, a material, in which the refractive index of the core layer  14  is 1.51 and a difference in the refractive index between the core layer  14  and the cladding layer is 0.01 to 0.2, is selected. Various films such as an alicyclic olefin film, an acrylic film, an epoxy film and a polyimide film can be used, but since particularly the layer with high refractive index becomes core portions  14 A of an optical waveguide, the light transmittance should be high. Since a layer with low refractive index serves as the cladding layer, even the layer with inferior light transmittance to the layer with high refractive index can be utilized.  
      It is preferable that the thickness of the double-layered polymer film  18  falls within a range of 70 μm to 200 μm in order to heighten following-up property of the optical waveguide with respect to deformation. Further, due to the similar reason, it is preferable that the width of the double-layered polymer film  18  falls within a range of 0.5 mm to 10 mm, and more preferably a range of 1 mm to 5 mm.  
      At the next step, as shown in  FIG. 1B , the core layer  14  of the double-layered polymer film  18  is cut by a dicing saw  21  having a multi-blade  20  shown in  FIG. 2 .  
      As shown in  FIG. 2 , the multi-blade  20  is composed of two kinds of blades with different outer diameters, blades  24  with small outer diameter are provided between blades  22  with large outer diameter, respectively.  
      When the core layer  14  is cut by the multi-blade  20 , it is divided by the blades  22  with large outer diameter, and the surfaces of the divided core layers are cut by the blades  24  with small outer diameter. In such a manner, a plurality of core portions  14 A of the optical waveguide are processed.  
      For example, in order to form the plural core portions  14 A with width of 50 μm and pitch of 250 μm, the blades  22  with large outer diameter with thickness of 50 μm and the blades  24  with small outer diameter with thickness of 200 μm are combined alternately. As a result, the core portions  14 A can be processed.  
      At the next step, as shown in  FIG. 1C , concave portions of the core layer  14  cut by the dicing saw  21  (see  FIG. 2 ) are filled with ultraviolet curing polymer resin by the spin-coating method. The core portion  14 A is coated with the polymer resin so that a cladding resin layer  16  is formed.  
      At the next step, as shown in  FIG. 1D , the cladding resin layer  16  is cured by UV irradiation using the UV irradiation device.  
      The double-layered polymer film  18  is, therefore, formed without using a substrate, and the optical waveguide can be manufactured by the inexpensive double-layered polymer film  18 .  
      In the manufacturing method according to the first exemplary embodiment, the polymer film  12  to be the cladding layer is fixed to the fixing table, and the polymer resin to be the core layer  14  with higher refractive index than the polymer film  12  is applied to the polymer film  12  and is cured, so that the double-layered polymer film is manufactured. Instead of this method, the polymer film is fixed to be the core layer  14  to the fixing table, and polymer resin to be a cladding layer with lower refractive index is applied to the core layer and is cured and the double-layered polymer film may be manufactured. In this case, when the double-layered polymer film is manufactured, the core layer is provided on the lower side. For this reason, the double-layered film is turned upside down so that the core layer is arranged on the upper side, and it should be cut by the dicing saw. In this case, for example, an alicyclic olefin film whose refractive index is 1.51 may be used as the core layer, and a fluorinated acrylic resin with low refractive index may be used as the cladding layer.  
      An optical waveguide manufacturing method according to a second exemplary embodiment of the present invention is explained below following the steps with reference to  FIGS. 3A  to  3 D.  
      As shown in  FIG. 3A , a plurality of adsorption ports  41  are formed on a fixing table  40  and the surface of another fixing table  44 , and a suction force is generated by a vacuum pump. A first polymer film  42  to be a first cladding layer is adsorbed and stuck to the fixing table  40 , so as to be fixed. A second polymer film  46  to be a second cladding layer which is the same material as the first polymer film  42  is adsorbed and stuck to the other fixing table  44  so as to be fixed. Further, an ultraviolet curing polymer resin with higher refractive index than the first polymer film  42  is uniformly applied to the first polymer film  42 , and the second polymer film  46  is overlapped with it and is irradiated with an UV ray by the UV ray irradiation device so as to be cured. As a result, a core layer  48  is formed, and a triple-layered polymer film  52  is manufactured.  
      At the next step, as shown in  FIG. 3B , the second polymer film  46  and the core layer  48  are cut by the dicing saw  21  having the multi-blade  20  (see  FIG. 2 ) which is used in the manufacturing method of the first exemplary embodiment. As a result, the core layer  48  is divided, so that a plurality of core portions  48 A of the optical waveguide are processed.  
      At the next step, as shown in  FIG. 3C , concave portions of the second polymer film  46  and the core layer  48  cut by the dicing saw  21  are filled with the UV curing polymer resin having the same refractive index as that of the second polymer film  46 . As a result, a cladding resin layer  50  is formed, and all the core portions  48 A are covered with the polymer resin with the same refractive index.  
      At the next step, as shown in  FIG. 3D , the cladding resin layer  50  is irradiated with an UV ray by the UV ray irradiation device so as to be cured.  
      In the manufacturing method according to the second exemplary embodiment, the first polymer film  42  to be the first cladding layer and the second polymer film  46  to be the second cladding layer are fixed to the fixing table  40  and the fixing table  44 , respectively. Further, the UV curing polymer resin with higher refractive index than the first polymer film  42  is uniformly applied to the first polymer film  42 . The second polymer film  46  is overlapped with the first polymer film  42  and is irradiated with an UV ray so as to be cured. As a result, the core layer  48  is formed, and the triple-layered polymer film  52  is manufactured. Instead of this, however, the UV curing polymer resin to be the cladding layer with lower refractive index than the core layer is uniformly applied to both the surfaces of the polymer film to be the core layer and is irradiated with an UV ray so as to be cured. In such a manner, the triple-layered polymer film may be manufactured.  
      An optical waveguide manufacturing method according to a third exemplary embodiment of the present invention is explained below following the steps with reference to  FIGS. 4A  to  5 .  
      As shown in  FIG. 4A , a plurality of adsorption ports  111  are formed on the surface of a fixing table  110 , and a suction force is generated by a vacuum pump. A polymer film  112  to be a cladding layer is adsorbed and stuck to the fixing table  110 , a UV curing polymer resin with high refractive index is uniformly applied (spin-coating) to the polymer film  112 , and is irradiated with an UV ray by the UV irradiation device so as to be cured. As a result, a core layer  114  and the polymer film  112  are formed, and a double-layered polymer film  118  is manufactured.  
      For example, a material in which the refractive index of the core layer  114  is 1.51 and a difference in the refractive index between the core layer  114  and the cladding layer is 0.01 to 0.2, is selected. Various films such as an alicyclic olefin film, an acrylic film, an epoxy film and a polyimide film can be used, but since particularly the layer with high refractive index becomes core portions  114 A of the optical waveguide, the light transmittance should be high. Since a layer with low refractive index serves as the cladding layer, even the layer with lower light transmittance than the layer with high refractive index can be utilized.  
      It is preferable that the thickness of the double-layered polymer film  118  falls within a range of 70 μm to 200 μm in order to heighten following-up property of the optical waveguide with respect to deformation. Further, due to the similar reason, it is preferable that the width of the double-layered polymer film  118  falls within a range of 0.5 mm to 10 mm, and more preferably a range of 1 mm to 5 mm.  
      At the next step, as shown in  FIG. 4B , the core layer  114  of the double-layered polymer film  118  is cut by the dicing saw  21  having the multi-blade  120  shown in  FIG. 5 .  
      As shown in  FIG. 5 , the multi-blade  120  is composed of two kinds of blades with different outer diameters, and blades  124  with small outer diameter are provided between blades  122  with large outer diameter, respectively.  
      When the core layer  114  is cut by the multi-blade  120 , the core layer  114  is divided by the blades  122  with large outer diameter, and the surfaces of the divided core layer  114  is cut by the blades  124  with small outer diameter. As a result, a plurality of core portions  114 A of the optical waveguide are processed. Further, simultaneously with the processing of the core portions  114 A, the core layer  114  is cut by the blades  122  with large outer diameter, and disposing portions  130  for disposing electric conductive lines for power supply are processed at both ends of the core layer  114 , respectively, so as to sandwich the core portions  114 A.  
      For example, in order to form the plural core portions  114 A with width of 50 μm and pitch of 250 μm, the blades  122  with large outer diameter with thickness of 50 μm and the blades  124  with small outer diameter with thickness of 200 μm are combined alternately. As a result, the core portions  114 A can be processed.  
      At the next step, as shown in  FIG. 4C , an electric conductive member is adhered to the disposing portion  130  so that electric conductive lines  132  for power supply are disposed, respectively. For example, the electric conductive lines  132  can be made of a material containing at least one kind selected from copper, iron, nickel, gold, aluminum, silver and their alloy. Further, the electric conductive lines  132  can be manufactured by applying a paste containing silver fine particles using a dispenser. The diameter of the electric conductive lines  132  can be smaller than the diameter of the core portions  114 A and can fall within a range of 3 μm to 200 μm.  
      At the next step, as shown in  FIG. 4D , concave portions of the core layer  114  cut by the dicing saw  21  (see  FIG. 5 ) and the disposing portions  130  are filled with ultraviolet curing polymer resin having the same refractive index as the cladding layer by the spin-coating method. The core portions  114 A are coated with the polymer resin so that a cladding resin layer  116  is formed.  
      At the next step, as shown in  FIG. 4E , the cladding resin layer  116  is cured by UV ray irradiation using the UV ray irradiation device.  
      The double-layered polymer film  118  is, therefore, formed without using a substrate, and the inexpensive optical waveguide having the electric conductive lines  132  for power supply can be manufactured by the inexpensive double-layered polymer film  118 .  
      In the manufacturing method according to the third exemplary embodiment, the polymer film  112  to be the cladding layer is fixed to the fixing table, and the polymer resin to be the core layer  114  with higher refractive index than the polymer film  112  is applied to the polymer film  112  and is cured, so that the double-layered polymer film is manufactured. Instead of this method, however, the polymer film to be the core layer is fixed to the fixing table, and polymer resin to be a cladding layer with lower refractive index than the core layer is applied to the core layer and is cured. In such a manner, the double-layered polymer film may be manufactured. In this case, when the double-layered polymer film is manufactured, the core layer is provided on the lower side. For this reason, the double-layered film is turned upside down so that the core layer is arranged on the upper side, and it should be cut by the dicing saw. In this case, for example, an alicyclic olefin film whose refractive index is 1.51 may be used as the core layer, and a fluorinated acrylic resin with low refractive index may be used as the cladding layer.  
      An optical waveguide manufacturing method according to a fourth exemplary embodiment of the present invention is explained below following the steps with reference to  FIGS. 6A  to  8 .  
      As shown in  FIG. 6A , a plurality of adsorption ports  61  are formed on the surface of a fixing table  60 , and a suction power is generated by a vacuum pump. A polymer film  62  to be a cladding layer is adsorbed and stuck to the fixing table  60 , and ultraviolet curing polymer resin with high refractive index is applied to the polymer film  62 . The polymer resin is irradiated with an UV ray by a UV ray irradiation device so as to be cured, and a core layer  64  and the polymer film  62  are formed so that a double-layered polymer film  68  is manufactured.  
      For example, a material, in which the refractive index of the core layer  64  is 1.51 and a difference in the refractive index between the core layer  64  and the cladding layer is 0.01 to 0.2, is selected. Various films such as an alicyclic olefin film, an acrylic film, an epoxy film and a polyimide film can be used, but since particularly the layer with high refractive index becomes a core portion  64 A of an optical waveguide, the light transmittance should be high. Since a layer with low refractive index serves as the cladding layer, even the layer with light transmittance inferior to the layer with high refractive index can be utilized.  
      It is preferable that the thickness of the double-layered polymer film  68  falls within a range of 70 μm to 200 μm in order to heighten following-up property of the optical waveguide with respect to deformation. Further, due to the similar reason, it is preferable that the width of the double-layered polymer film  68  falls within a range of 0.5 mm to 10 mm, and more preferably a range of 1 mm to 5 mm.  
      At the next step, as shown in  FIG. 6B , the core layer  64  of the double-layered polymer film  68  is cut by a dicing saw having a multi-blade  70 .  
      The multi-blade  70  is composed of two kinds of blades with different outer diameters, blades  74  with small outer diameter are provided between blades  72  with large outer diameter, respectively.  
      When the core layer  64  is cut by the multi-blade  70 , it is divided by the blades  72  with large outer diameter, and the surfaces of the divided core layer  64  are cut by the blades  74  with small outer diameter. In such a manner, a plurality of core portions  64 A of the optical waveguide are processed.  
      For example, in order to form the plural core portions  64 A with width of 50 μm and pitch of 250 μm, the blades  72  having large outer diameter and thickness of 50 μm, and the blades  74  having small outer diameter and thickness of 200 μm are combined alternately. As a result, the core portions  64 A can be processed.  
      At the next step, as shown in  FIG. 6C , concave portions of the cut core layer  64  are filled with ultraviolet curing polymer resin with the same refractive index with the cladding layer by the spin-coating method. The core portions  64 A are coated with the polymer resin so that a cladding resin layer  66  is formed.  
      At the next step, as shown in  FIG. 6D , a pair of electric conductive lines  76 A for power supply shown in  FIG. 7  are provided to the cladding resin layer  66 , and a polymer film  76  with electric conductive line whose refractive index is the same as the cladding layer is laminated to the cladding resin layer  66 . For example, the electric conductive lines  76 A can be made of a material containing at least one kind selected from a copper, iron, nickel, gold, aluminum, silver and their alloy. Further, the electric conductive lines  76 A can be manufactured by applying paste containing silver fine particles using a dispenser.  
      At the next step, as shown in  FIG. 6E , the cladding resin layer is cured by UV ray irradiation using the UV ray irradiation device, and the polymer film  76  with electric conductive lines is stuck to the cladding resin layer  66 . As a result, the optical waveguide shown in  FIG. 8  can be manufactured.  
      The double-layered polymer film  68  is, therefore, formed without using a substrate, and the inexpensive optical waveguide having the electric conductive lines  76 A for power supply can be manufactured by the inexpensive double-layered polymer film  68  and the polymer film  76  with electric conductive lines.  
      In the manufacturing method according to the fourth exemplary embodiment, the polymer film  62  to be the cladding layer is fixed to the fixing table, and the polymer resin to be the core layer  64  with higher refractive index than the polymer film  62  is applied to the polymer film  62  and is cured, so that the double-layered polymer film  68  is manufactured. Instead of this method, however, the polymer film to be the core layer  14  is fixed to the fixing table, and polymer resin to be a cladding layer with lower refractive index is applied to the core layer and is cured. In such a manner, the double-layered polymer film may be manufactured. In this case, when the double-layered polymer film is manufactured, the core layer is provided to the lower side. For this reason, the double-layered film is turned upside down so that the core layer is arranged on the upper side, and it should be cut by the dicing saw. In this case, for example, an alicyclic olefin film whose refractive index is 1.51 may be used as the core layer, and a fluorinated acrylic resin with low refractive index may be used as the cladding layer.  
      An optical waveguide manufacturing method according to a fifth exemplary embodiment of the invention is explained below following the steps with reference to  FIGS. 9A  to  9 E.  
      As shown in  FIG. 9A , a plurality of adsorption ports  141  are formed on a fixing table  140  and the surface of another fixing table  144 , and a suction force is generated by a vacuum pump. A first polymer film  142  to be a first cladding layer is adsorbed and stuck to the fixing table  140 , so as to be fixed. A second polymer film  146  to be a second cladding layer which is the same material as the first polymer film  142  is adsorbed and stuck to the fixing table  144  so as to be fixed. Further, an ultraviolet curing polymer resin with higher refractive index than the first polymer film  142  is applied to the first polymer film  142 , and the second polymer film  146  is overlapped with it and is irradiated with an UV ray by the UV ray irradiation device so as to be cured. As a result, a core layer  148  is formed, and a triple-layered polymer film  152  is manufactured.  
      At the next step, as shown in  FIG. 9B , the second polymer film  146  and the core layer  148  are cut by the dicing saw having the multi-blade  154 .  
      The multi-blade  154  is composed of two kinds of blades with different outer diameters, and blades  156  with small outer diameter are provided between blades  155  with large outer diameter, respectively.  
      When the core layer  148  is cut by the multi-blade  154 , it is divided by the blades  155  with large outer diameter, and the core portions  148 A of the plurality of optical waveguide are processed. Further, simultaneously with the processing of the core portions  148 A, the core layer  148  is cut by the blades  155  with large outer diameter, and disposing portions  157  for disposing electric conductive lines for power supply are processed at both ends of the core layer  148 , respectively, so as to sandwich the core portions  148 A.  
      At the next step, as shown in  FIG. 9C , an electric conductive member is adhered to the disposing portion  157  so that electric conductive line  158  for power supply are disposed. For example, the electric conductive lines  158  can be made of a material containing at least one kind selected from copper, iron, nickel, gold, aluminum, silver and their alloy. Further, the electric conductive lines  158  can be manufactured by applying paste containing silver fine particles using a dispenser. The diameter of the electric conductive lines  158  can be smaller than the diameter of the core portions  148 A and can fall within a range of 3 μm to 200 μm.  
      At the next step, as shown in  FIG. 9D , concave portions of the triple-layered polymer film cut by the dicing saw and the disposing portions  157  are filled with ultraviolet curing polymer resin having the same refractive index as the first cladding layer by the spin-coating method. In such a manner, a cladding resin layer  150  is formed.  
      At the next step, as shown in  FIG. 9E , the cladding resin layer  150  is cured by UV ray irradiation using the black light.  
      The triple-layered polymer film  152  is, therefore, formed without using a substrate, and the inexpensive optical waveguide having the electric conductive line  158  for power supply can be manufactured by the inexpensive triple-layered polymer film  152 .  
      In the manufacturing method according to the fifth exemplary embodiment, the first polymer film  142  to be the first cladding layer and the second polymer film  146  to be the second cladding layer are fixed to the fixing table  140  and the fixing table  144 , respectively. Further, the UV curing polymer resin with higher refractive index than the first polymer film  142  is uniformly applied to the first polymer film  142 . The second polymer film  146  is overlapped with the first polymer film  142  and is irradiated with an UV ray so as to be cured. As a result, the core layer  148  is formed, and the triple-layered polymer film  152  is manufactured. Instead of this, however, the UV curing polymer resin to be the cladding layer with lower refractive index than the core layer is uniformly applied to both the surfaces of the polymer film to be the core layer and is irradiated with an UV ray so as to be cured. In such a manner, the triple-layered polymer film may be manufactured.  
      An optical waveguide manufacturing method according to a sixth exemplary embodiment of the present invention is explained below following the steps with reference to  FIGS. 10A  to  10 E.  
      As shown in  FIG. 10A , a plurality of adsorption ports  81  are formed on a fixing table  80  and another fixing table  84 , and a suction force is generated by a vacuum pump. A first polymer film  82  to be a first cladding layer is adsorbed to and stuck to the fixing table  80 , so as to be fixed. A second polymer film  86  to be a second cladding layer which is the same material as the first polymer film  82  is adsorbed and stuck to the fixing table  84  so as to be fixed. Further, an ultraviolet curing polymer resin with higher refractive index than the first polymer film  82  is applied to the first polymer film  82 , and the second polymer film  86  is overlapped with it and is irradiated with an UV ray by the UV ray irradiation device so as to be cured. As a result, a core layer  88  is formed, and a triple-layered polymer film  92  is manufactured.  
      At the next step, as shown in  FIG. 10B , the second polymer film  86  and the core layer  88  are cut by the dicing saw having the multi-blade  94 .  
      The multi-blade  94  is composed of two kinds of blades with different outer diameters, and blades  96  with small outer diameter are provided between blades  95  with large outer diameter, respectively.  
      The core layer  88  is cut by the multi-blade  94  and is divided by the blades  95  with large outer diameter, so that a plurality of core portions  88 A of the optical waveguide are processed.  
      At the next step, as shown in  FIG. 10C , concave portions of the cut triple-layered polymer film  92  are filled with ultraviolet curing polymer resin having the same refractive index as the first cladding layer by the spin-coating method, and the second polymer film  86  is covered with the polymer resin. In such a manner, a cladding resin layer  87  is formed.  
      At the next step, as shown in  FIG. 10D , a pair of electric conductive lines  98 A for power supply are provided to the cladding resin layer  87 , and a polymer film  98  with electric conductive lines whose refractive index is the same as the cladding layer is laminated to the cladding resin layer  87 . For example, the electric conductive lines  98 A can be made of a material containing at least one kind selected from a copper, iron, nickel, gold, aluminum, silver and their alloy. Further, the electric conductive lines  98 A can be manufactured by applying paste containing silver fine particles using a dispenser.  
      At the next step, as shown in  FIG. 10E , the cladding resin layer  87  is cured by UV ray irradiation using the UV ray irradiation device, and the polymer film  98  with electric conductive lines is stuck to the cladding resin layer  87 .  
      The triple-layered polymer film  92  is, therefore, formed without using a substrate, and the inexpensive optical waveguide having the electric conductive lines  98 A for power supply can be manufactured by the inexpensive triple-layered polymer film  92  and the polymer film  98  with electric conductive lines.  
      In the manufacturing method according to the sixth exemplary embodiment, the first polymer film  82  to be the first cladding layer and the second polymer film  86  to be the second cladding layer are fixed to the fixing table  80  and the fixing table  84 , respectively. The ultraviolet curing polymer resin with higher refractive index than the first polymer film  82  is uniformly applied to the first polymer film  82 . The second polymer film  86  is overlapped with the first polymer film  82  and is irradiated with an UV ray so as to be cured. As a result, a core layer  88  is formed, and the triple-layered polymer film  92  is manufactured. Instead of this method, however, an UV curing polymer resin to be the cladding layer whose refractive index is lower than the core layer is uniformly applied to both the surfaces of the polymer film to be the core layer, and is irradiated with an UV ray so as to be cured. In such a manner, the triple-layered polymer film may be manufactured.  
     EXAMPLES  
      The examples are explained below more concretely, but the invention is not limited to these examples.  
     Example 1  
      According to the manufacturing method of the first exemplary embodiment, an epoxy film (thickness: 50 μm, refractive index: 1.60) to be the core layer having high refractive index is adsorbed and stuck to the table. An acrylic UV curing resin to be the cladding layer with refractive index of 1.51 is applied with thickness of 25 μm to the epoxy film, and is irradiated with an UV ray to be cured. In such a manner, a double-layered polymer film is manufactured.  
      The double-polymer film is cut by a dicing saw with multi-wheel blade with accuracy of 55±5 μm from the core layer side. At this time, multi-blade, in which the blades with large outer diameter with thickness of 50 μm and blades with small outer diameter with thickness of 200 μm are combined alternately, is used.  
      An acrylic UV curing resin with refractive index of 1.51 is applied to the upper portion of the core layer into thickness of 25 μm, and is irradiated with an UV ray so as to be cured.  
      Finally, the double layered polymer film is diced by a normal blade, so that an optical waveguide is manufactured.  
      As a result, the inexpensive optical waveguide having a plurality of core portions in which the width of the core portions is 50 μm and a pitch is 250 μm can be manufactured by one-time cutting.  
     Example 2  
      According to the manufacturing method of the first exemplary embodiment, an arton film to be the cladding layer (made by JSR, thickness: 25 μm, refractive index: 1.51) is adsorbed to be stuck to the table. An acrylic UV curing resin with refractive index of 1.59 is applied to the film into a thickness of 50 μm, and is irradiated with an UV ray so as to be cured. In such a manner, a double-layered polymer film is manufactured.  
      The double-layered polymer film is cut by a dicing saw with a multi-wheel blade with accuracy of 55±5 μm from the core layer side. At this time, the multi-blade, in which blades having large outer diameter and thickness of 50 μm, and blades having small outer diameter and thickness of 200 μm are combined alternately, is used.  
      An acrylic UV curing resin with refractive index of 1.51 is applied to the upper portion of the cut core layer into a thickness of 25 μm, and is irradiated with an UV ray so as to be cured.  
      Finally, the double-layered polymer film is diced by using a normal blade, so that an optical waveguide is manufactured.  
      As a result, the inexpensive optical waveguide, which has a plurality of core portions with width of 50 μm and with pitch of 250 μm, can be manufactured by one-time cutting.  
     Example 3  
      According to the manufacturing method of the second exemplary embodiment, an epoxy film with high refractive index (thickness of 50 μm, refractive index: 1.60) to be the core layer is used. An acrylic UV curing resin with refractive index of 1.51 is uniformly applied to both surfaces of the core layer into a thickness of 20 μm. The acrylic UV curing resin is irradiated with an UV ray so as to be cured. In such a manner, a triple-layered polymer film is manufactured.  
      The triple-layered polymer film is cut by a dicing saw with a multi-wheel blade with accuracy of 75±5 μm. At this time, a multi-blade, in which blades with large outer diameter and thickness of 50 μand blades with small outer diameter and thickness of 200 μm are combined alternately, is used.  
      An acrylic UV curing resin with refractive index of 1.51 is applied to fill the concave portions, and is irradiated with an UV ray so as to be cured.  
      Finally, the triple-layered polymer film is diced by using a normal blade, so that an optical waveguide is manufactured.  
      As a result, the inexpensive optical waveguide, which has a plurality of core portions with width of 50 μm and with pitch of 250 μm, can be manufactured by one-time cutting.  
     Example 4  
      According to the manufacturing method of the first exemplary embodiment, a fluorinated polyimide film to be the cladding layer (thickness of 20 μm, refractive index: 1.55) is adsorbed to be stuck to the table. An epoxy UV curing resin with refractive index of 1.62 is applied to the film into a thickness of 50 μm. The epoxy UV curing resin is irradiated with an UV ray so as to be cured. In such a manner, a double-layered polymer film is manufactured.  
      The double-layered polymer film is cut by a dicing saw with a multi-wheel blade with accuracy of 55±5 μm from the core layer side. At this time, the multi-blade, in which blades having large outer diameter and thickness of 50 μm, and blades having small outer diameter and thickness of 200 μm are combined alternately, is used.  
      A fluorinated polyamic acid whose refractive index becomes 1.55 after curing is applied to the upper portion of the cut core layer into a thickness of 10 μm, and is heated to be cured at 250° C. As a result, a polyimide film is formed.  
      Finally, the double-layered polymer film is diced by using a normal blade, so that an optical waveguide is manufactured.  
      As a result, the inexpensive optical waveguide, which has a plurality of core portions with width of 50 μm and with pitch of 250 μm, can be manufactured by one-time cutting.  
     Example 5  
      According to the manufacturing method of the first exemplary embodiment, a heat-resistance olefin film to be the core layer (thickness: 50 μm, refractive index: 1.62, Tg: 280° C.) is adsorbed to be stuck to the table. An epoxy UV curing resin with refractive index of 1.55 is applied to the olefin film into a thickness of 20 μm, and is irradiated with an UV ray so as to be cured. Further, the epoxy UV curing resin is heated to 200° C. so as to be sufficiently cured. As a result, a double-layered polymer film with flexibility is manufactured.  
      The double-layered polymer film is cut by a dicing saw with a multi-wheel blade with accuracy of 55±5 μm from the core layer side. At this time, the multi-blade, in which blades having large outer diameter with thickness of 50 μm and blades having small outer diameter with thickness of 200 μm are combined alternately, is used.  
      An epoxy UV curing resin with refractive index of 1.55 is applied to the double-layered polymer film into a thickness of 20 μm, and is irradiated with an UV ray so as to be cured. The epoxy UV curing resin is further heated to 200° C. so as to be cured sufficiently. As a result, flexibility is obtained.  
      Finally, the double-layered polymer film is diced by using a normal blade, so that an optical waveguide is manufactured.  
      As a result, the inexpensive optical waveguide, which has a plurality of core portions with width of 50 μm and with pitch of 250 μm, can be manufactured by one-time cutting.  
     Example 6  
      According to the manufacturing method of the first and second exemplary embodiments, an alicyclic acryl film with small volume contraction and high transparency is used as the polymer film to be the cladding layer. A high-performance optical waveguide in which deformation is less at the time of processing can be manufactured.  
     Example 7  
      According to the manufacturing method of the first and second exemplary embodiments, an alicyclic olefin film with small volume contraction and high transparency is used as the polymer film to be the cladding layer. A high-performance optical waveguide in which deformation is less at the time of processing can be manufactured.  
     Example 8  
      According to the manufacturing method of the first and second exemplary embodiments, an UV curing acrylic resin with small volume contraction is used as the polymer resin to be the core layer. A high-performance optical waveguide in which deformation is less at the time of processing can be manufactured.  
     Example 9  
      According to the manufacturing method of the first and second exemplary embodiments, an UV curing acrylic resin with small volume contraction is used as the polymer resin to be the core layer. A high-performance optical waveguide in which deformation is less at the time of processing can be manufactured.  
     Example 10  
      According to the manufacturing method of the first exemplary embodiment, an UV curing epoxy resin with small volume contraction is used as the polymer resin to be the cladding layer. A high-performance optical waveguide in which deformation is less at the time of processing can be manufactured.  
     Example 11  
      According to the manufacturing method of the first exemplary embodiment, an UV curing acrylic resin with small volume contraction is used as the polymer resin to be the cladding layer. A high-performance optical waveguide in which deformation is less at the time of processing can be manufactured.  
     Example 12  
      According to the manufacturing method of the first exemplary embodiment, an alicyclic acryl film with small volume contraction and high transparency is used as the polymer film to be the core layer. A high-performance optical waveguide in which deformation is less at the time of processing can be manufactured.  
     Example 13  
      According to the manufacturing method of the first exemplary embodiment, an alicyclic olefin film with small volume contraction and high transparency is used as the polymer film to be the core layer. A high-performance optical waveguide in which deformation is less at the time of processing can be manufactured.  
     Example 14  
      According to the manufacturing methods of the first and second exemplary embodiment, when the dicing saw with multi-blade is moved to a rotating axis direction, the core layer is processed into the core portions of the optical waveguide by plural steps of cutting. The plural core portions can be processed in a plurality of places.  
     Example 15  
      According to the manufacturing methods of the first and second exemplary embodiment, in the multi-blade, the blades of large outer diameter are arranged with intervals of 10 to 300 μm so as to be assembled. That is, the blades having small outer diameter and thickness of 10 to 300 μm are assembled between the blades of large outer diameter. Since the blades with small outer diameter has a generalized thickness, the plural core portions can be processed by using the inexpensive multi-blade.  
     Example 16  
      According to the manufacturing methods of the first and second exemplary embodiment, in the multi-blade, the gap between the blades with large outer diameter is adjusted by overlapping plural blade with small outer diameter. The distance between the blades with large outer diameter can be adjusted easily without using a spacer.  
     Example 17  
      According to the manufacturing methods of the first and second exemplary embodiment, in the multi-blade, a length, which is obtained by adding the thickness of the blades with large outer diameter and the thickness of the blades with small outer diameter is determined as the pitch of the core portions. The plural core portions can be processed together at once.  
     Example 18  
      According to the manufacturing method of the third exemplary embodiment, an epoxy film with high refractive index (thickness: 50 μm, refractive index: 1.60) to be the core layer is adsorbed to be stuck to the table. An acrylic UV curing resin with refractive index of 1.51 to be the cladding layer is uniformly applied to the core layer into a thickness of 25 μm. The acrylic UV curing resin is irradiated with an UV ray so as to be cured. In such a manner, a double-layered polymer film is manufactured.  
      The double-layered polymer film is cut by a dicing saw with a multi-wheel blade with accuracy of 55±5 μm from the core layer side, so that a plurality of core portions and two disposing portions are processed. At this time, the multi-blade, in which blades having large outer diameter with thickness of 50 μm and blades having small outer diameter with thickness of 200 μm are combined alternately, is used.  
      The two disposing portions are filled with silver paste by a dispenser, so that electric conductive lines are disposed.  
      An acrylic UV curing resin with refractive index of 1.51 is applied to the upper portion of the cut core layer into a thickness of 25 μm, and is irradiated with an UV ray so as to be cured.  
      Finally, the double layered polymer film is diced by a normal blade, so that an optical waveguide is manufactured.  
      As a result, the inexpensive optical waveguide, which has a plurality of core portions whose pitch is 250 μm and width is 50 μm and the electric conductive lines, can be manufactured by one-time cutting.  
     Example 19  
      According to the manufacturing method of the third exemplary embodiment, an arton film to be the cladding layer (made by JSR, thickness: 25 μm, refractive index: 1.51) is adsorbed to be stuck to the table. An acrylic UV curing resin with refractive index of 1.59 is applied to the film into a thickness of 50 μm, and is irradiated with an UV ray so as to be cured. In such a manner, a double-layered polymer film is manufactured.  
      The double-layered polymer film is cut by a dicing saw with a multi-wheel blade with accuracy of 55±5 μm from the core layer side, so that a plurality of core portions and two disposing portions are processed. At this time, the multi-blade, in which blades having large outer diameter and thickness of 50 μm, and blades having small outer diameter and thickness of 200 μm are combined alternately, is used.  
      Copper lines are constructed on the two disposing portions, respectively, so that electric conductive lines are disposed.  
      An acrylic UV curing resin with refractive index of 1.51 is applied to the upper portion of the cut core layer into a thickness of 25 μm, and is irradiated with an UV ray so as to be cured.  
      Finally, the double layered polymer film is diced by a normal blade, so that an optical waveguide is manufactured.  
      As a result, the inexpensive optical waveguide, which has a plurality of core portions whose pitch is 250 μm and width is 50 μm and the electric conductive lines, can be manufactured by one-time cutting.  
     Example 20  
      According to the manufacturing method of the fifth exemplary embodiment, an epoxy film with high refractive index (thickness of 50 μm, refractive index: 1.60) to be the core layer is used. An acrylic UV curing resin with refractive index of 1.51 is uniformly applied to both surfaces of the core layer into a thickness of 20 μm. The acrylic UV curing resin is irradiated with an UV ray so as to be cured. In such a manner, a triple-layered polymer film is manufactured.  
      The triple-layered polymer film is cut by a dicing saw having a multi-wheel blade with accuracy of 75±5 μm, so that a plurality of core portions and two disposing portions are processed. At this time, a multi-blade, in which blades having large outer diameter and thickness of 50 μm, and blades having small outer diameter and thickness of 200 μm are combined alternately, is used.  
      Copper lines are constructed on the two disposing portions, respectively, so that electric conductive lines are disposed.  
      An acrylic UV curing resin with refractive index of 1.51 is applied so as to fill cut concave portions, and is irradiated with an UV ray so as to be cured.  
      Finally, the triple-layered polymer film is diced by a normal blade, so that an optical waveguide is manufactured.  
      As a result, the inexpensive optical waveguide, which has a plurality of core portions whose pitch is 250 μm and width is 50 μm and the electric conductive lines, can be manufactured by one-time cutting.  
     Example 21  
      According to the manufacturing method of the fourth exemplary embodiment, an arton film to be the cladding layer (made by JSR, thickness: 25 μm, refractive index: 1.51) is adsorbed to be stuck to the table. An acrylic UV curing resin with refractive index of 1.59 is applied to the film into a thickness of 50 μm, and is irradiated with an UV ray so as to be cured. In such a manner, a double-layered polymer film is manufactured.  
      The double-layered polymer film is cut by a dicing saw with a multi-wheel blade with accuracy of 55±5 μm from the core layer side, so that a plurality of core portions are processed. At this time, the multi-blade, in which blades having large outer diameter and thickness of 50 μm, and blades having small outer diameter and thickness of 200 μm are combined alternately, is used.  
      An acrylic UV curing resin with refractive index of 1.51 is applied to the upper portion of the cut core layer into a thickness of 25 μm.  
      An arton film (made by JSR, thickness: 25 μm, refractive index: 1.51) on which silver power supply lines are patterned by vacuum evaporation and etching is laminated as a polymer film with electric conductive lines to the applied acrylic UV curing resin. Thereafter, the acrylic UV curing resin is irradiated with an UV ray so as to be cured.  
      Finally, the double layered polymer film is diced by a normal blade, so that an optical waveguide is manufactured.  
      As a result, the inexpensive optical waveguide, which has a plurality of core portions whose pitch is 250 μm and width is 50 μm and the electric conductive lines, can be manufactured by one-time cutting.  
     Example 22  
      According to the manufacturing method of the fourth exemplary embodiment, an arton film to be the cladding layer (made by JSR, thickness: 25 μm, refractive index: 1.51) is adsorbed to be stuck to the table. An acrylic UV curing resin with refractive index of 1.59 is applied to the film into a thickness of 50 μm, and is irradiated with an UV ray so as to be cured. In such a manner, a double-layered polymer film is manufactured.  
      The double-layered polymer film is cut by a dicing saw with a multi-wheel blade with accuracy of 55±5 μm from the core layer side, so that a plurality of core portions are processed. At this time, the multi-blade, in which blades having large outer diameter and thickness of 50 μm, and blades having small outer diameter and thickness of 200 μm are combined alternately, is used.  
      An acrylic UV curing resin with refractive index of 1.51 is applied to the upper portion of the cut core layer into a thickness of 25 μm.  
      An arton film (made by JSR, thickness: 25 μm, refractive index: 1.51) on which gold power supply lines are patterned by sputtering and etching is laminated as a polymer film with an electric conductive lines to the applied acrylic UV curing resin. Thereafter, the acrylic UV curing resin is irradiated with an UV ray so as to be cured.  
      Finally, the double layered polymer film is diced by a normal blade, so that an optical waveguide is manufactured.  
      As a result, the inexpensive optical waveguide, which has a plurality of core portions whose pitch is 250 μm and width is 50 μm and the electric conductive lines, can be manufactured by one-time cutting.  
     Example 23  
      According to the manufacturing methods of the third to sixth exemplary embodiments, metal paste is applied by a dispenser, so that electric conductive lines for power supply are disposed. Since this is a general method, the electric conductive liens can be disposed inexpensively.  
     Example 24  
      According to the manufacturing methods of the third to sixth exemplary embodiments, an electric conductive member is adhere by a sputtering method, so that electric conductive lines for power supply are disposed. Since a generalized device can be used, the electric conductive lines can be disposed inexpensively.  
     Example 25  
      According to the manufacturing methods of the third to sixth exemplary embodiments, an alicyclic acryl film with small volume contraction and high transparency is used as the polymer film to be the cladding layer. A high-performance optical waveguide in which deformation is less at the time of processing can be manufactured.  
     Example 26  
      According to the manufacturing methods of the third to sixth exemplary embodiments, an alicyclic olefin film with small volume contraction and high transparency is used as the polymer film to be the cladding layer. A high-performance optical waveguide in which deformation is less at the time of processing can be manufactured.  
     Example 27  
      According to the manufacturing methods of the third to sixth exemplary embodiments, an UV curing epoxy resin with small volume contraction is used as the polymer resin to be the core layer. A high-performance optical waveguide in which deformation is less at the time of processing can be manufactured.  
     Example 28  
      According to the manufacturing method of the third to sixth exemplary embodiments, an UV curing acrylic resin with small volume contraction is used as the polymer resin to be the core layer. A high-performance optical waveguide in which deformation is less at the time of processing can be manufactured.  
     Example 29  
      According to the manufacturing methods of the third and fourth exemplary embodiments, an UV curing epoxy resin with small volume contraction is used as the polymer resin to be the cladding layer. A high-performance optical waveguide in which deformation is less at the time of processing can be manufactured.  
     Example 30  
      According to the manufacturing methods of the third and fourth exemplary embodiments, an UV curing acrylic resin with small volume contraction is used as the polymer resin to be the cladding layer. A high-performance optical waveguide in which deformation is less at the time of processing can be manufactured.  
     Example 31  
      According to the manufacturing methods of the third and fourth exemplary embodiments, an alicyclic acryl film with small volume contraction and high transparency is used as the polymer film to be the core layer. A high-performance optical waveguide in which deformation is less at the time of processing can be manufactured.  
     Example 32  
      According to the manufacturing methods of the third and fourth exemplary embodiments, an alicyclic olefin film with small volume contraction and high transparency is used as the polymer film to be the core layer. A high-performance optical waveguide in which deformation is less at the time of processing can be manufactured.  
     Example 33  
      According to the manufacturing method of the third to sixth exemplary embodiments, when the dicing saw with multi-blade is moved to the rotating axis direction, the core layers are processed into core portions of the optical waveguide by plural steps of cutting. The plural core portions can be processed in plural places.  
     Example 34  
      According to the manufacturing methods of the third to sixth exemplary embodiments, in the multi-blade, the blades of large outer diameter are arranged with an interval of 10 to 300 μm so as to be assembled. That is, the blades having small outer diameter and thickness of 10 to 300 μm are assembled between the blades of large outer diameter. Since the blades with small outer diameter has a generalized thickness, the plural core portions can be processed by using the inexpensive multi-blade.  
     Example 35  
      According to the manufacturing methods of the third to sixth exemplary embodiments, in the multi-blade, the gap between the blades with large outer diameter is adjusted by overlapping the plural blades with small outer diameter. The distance between the blades with large outer diameter can be adjusted easily without using a spacer.  
     Example 36  
      According to the manufacturing methods of the third to sixth exemplary embodiments, in the multi-blade, a length, which is obtained by adding the thickness of the blades with large outer diameter and the thickness of the blades with small outer diameter is determined as the pitch of the core portions. The plural core portions can be processed together at once.