Optical waveguide

Abstract

Disclosed herein is an optical waveguide comprising a core layer to be an optical transmission region, an upper clad layer and a lower clad layer covering the core layer, in which the core layer, the upper clad layer and the lower clad layer are formed from resin materials, characterized in that a microlens made of a material having a higher refractive index than that of a material constituting said core layer is disposed in the vicinity of an end face of said core layer.

1 . An optical waveguide comprising; a core layer to be an optical transmission region; and an upper clad layer and a lower clad layer covering said core layer; in which said core layer, said upper clad layer and said lower clad layer are formed from resin materials; 
 wherein a microlens made of a material having a higher refractive index than that of a material constituting said core layer is disposed in the vicinity of an end face of said core layer.    
   
   
       2 . The optical waveguide according to  claim 1 , characterized in that said microlens has a curved-face partially in its outside shape.  
   
   
       3 . The optical waveguide according to  claim 1 , characterized in that said microlens has a substantially spherical shape.  
   
   
       4 . The optical waveguide according to  claim 3 , characterized in that said core layer is disposed in a groove formed in said lower clad layer or said upper clad layer, and said microlens is disposed in said groove in a state of being positioned by meeting its outer surface with at least two inner wall surfaces of said groove.  
   
   
       5 . An optical waveguide comprising; a core layer to be an optical transmission region; and an upper clad layer and a lower clad layer covering said core layer; in which said core layer, said upper clad layer and said lower clad layer are formed from resin materials; characterized in that said optical waveguide is constructed in such a way that a light guided in the core layer is scattered by a light scattering region, which is formed by containing bubbles or particles in a part of said core layer, so that a part of the scattered light is extracted out of the optical waveguide.  
   
   
       6 . The optical waveguide according to  claim 5 , characterized in that a diameter of said bubble or particle is at least a wavelength of the waveguided light.  
   
   
       7 . The optical waveguide according to  claim 5 , characterized in that said bubbles are formed in said core layer by injecting a material for forming said core layer containing bubbles.  
   
   
       8 . An optical waveguide comprising; a core layer to be an optical transmission region; and an upper clad layer and a lower clad layer covering said core layer; in which said core layer, said upper clad layer and said lower clad layer are formed from resin materials; characterized in that a light scattering region containing bubbles or particles is formed in a part of said upper clad layer and/or said lower clad layer.  
   
   
       9 . The optical waveguide according to  claim 8 , characterized by being constructed in such a way that a part of emitted light in the clad layer can be extracted out of the optical waveguide by said light scattering region.  
   
   
       10 . The optical waveguide according to  claim 8 , characterized in that said bubbles are formed in said clad layer by injecting a material for forming said clad layer containing bubbles.  
   
   
       11 . The optical waveguide according to  claim 8 , characterized in that said optical waveguide is formed by covering said upper clad layer and/or said lower clad layer with a mold having a projection so as to concentrate bubbles around the projection, when curing said upper clad layer and/or said lower clad layer.  
   
   
       12 . An optical waveguide comprising; a core layer to be an optical transmission region; and an upper clad layer and a lower clad layer covering said core layer; in which said core layer, said upper clad layer and said lower clad layer are formed from resin materials; characterized in that spacers are disposed between said upper clad layer and said lower clad layer around said core layer.  
   
   
       13 . The optical waveguide according to  claim 12 , characterized in that said spacers are disposed in only one region of both regions straggling said core layer.  
   
   
       14 . The optical waveguide according to  claim 13 , characterized in that in a curved portion of said optical transmission region, said spacers are disposed only in an inside region of the curved portion.