Optical element and method of fabrication thereof

Abstract

An optical element has a substrate having or not having a channel for optical waveguide; and a material which has a refractive index higher than that of the substrate and is filled in the channel for optical waveguide or is disposed on the substrate; wherein the refractive index in a part of the material varies substantially periodically or is substantially continuously monotone increasing or decreasing in the direction of light propagation.

1 . An optical element comprising: a substrate having or not having a channel for optical waveguide; and a material which has a refractive index higher than that of said substrate and is filled in said channel for optical waveguide or is disposed on said substrate; wherein 
 the refractive index in a part of said material varies substantially periodically or is substantially continuously monotone increasing or decreasing in a direction substantially perpendicular to the direction of light propagation.    
     
     
         2 . An optical element comprising: 
 a substrate having or not having a channel for an optical waveguide; and    a resin which has a refractive index higher than that of said substrate and is filled in said channel for optical waveguide or is disposed on said substrate;    wherein the refractive index in a part of said resin varies monotonically in the direction of light propagation and/or in a direction substantially perpendicular to said direction of light propagation.    
     
     
         3 . An optical element according to  claim 2 , said part of resin the refractive index of which varies is formed using the photo-hardening or thermo-hardening property of said resin.  
     
     
         4 . An optical element comprising: 
 a substrate having or not having a channel for an optical waveguide; and    a material which has a refractive index higher than that of said substrate and is filled in said channel for optical waveguide or is disposed on said substrate;    wherein said optical element further includes a plurality of temperature controlling elements disposed on said material and for partially changing the temperature of said material in a direction substantially perpendicular to the direction of light propagation.    
     
     
         5 . An optical element comprising: 
 a substrate having or not having a channel for an optical waveguide; and    a material which has a refractive index higher than that of said substrate and is filled in said channel for optical waveguide or is disposed on said substrate;    wherein said optical element further includes a plurality of electrodes disposed on said material and for partially changing the electric field in said material in the direction of light propagation and/or in a direction substantially perpendicular to said direction of light propagation.    
     
     
         6 . An optical element comprising: 
 a substrate having a channel for an optical waveguide; and    a material which has a refractive index higher than that of said substrate and is filled in said channel for optical waveguide or is disposed on said substrate;    wherein said optical element further comprises a part where said material protrudes to the direction of said substrate and/or a part where said substrate protrudes to the direction of said material, in the direction of light propagation and/or in a direction substantially perpendicular to the direction of light propagation.    
     
     
         7 . An optical element according to  claim 6 , wherein said protruding parts are provided substantially periodically.  
     
     
         8 . A method of fabrication of an optical element comprising the steps of: 
 a) forming photo-hardening resin on a substrate; and    b) irradiating light onto said photo-hardening resin, thereby hardening said photo-hardening resin;    wherein the amount of said light irradiation in step (b) is varied.    
     
     
         9 . A method of fabrication of an optical element according to  claim 8 , wherein the amount of said light irradiation in step (b) is varied substantially periodically or is substantially continuously monotone increasing or decreasing, in a predetermined direction on the surface of said photo-hardening resin.  
     
     
         10 . A method of fabrication of an optical element according to  claim 8  or  9 , wherein the intensity of said light irradiation onto said photo-hardening resin in step (b) is varied, whereby the amount of said light irradiation onto the surface of said photo-hardening resin is varied.  
     
     
         11 . A method of fabrication of an optical element according to  claim 10 , wherein a mask having partially different light transmissivity is used, whereby the intensity of said light irradiation onto the surface of said photo-hardening resin in step (b) is varied.  
     
     
         12 . A method of fabrication of an optical element according to  claim 8  or  9 , wherein a light shielding plate is used so as to sequentially change the region irradiated by said light, whereby the amount of said light irradiation onto said photo-hardening resin in step (b) is varied.  
     
     
         13 . A method of fabrication of an optical element comprising the steps of: 
 a) forming photo-hardening resin on a substrate;    b) connecting an optical component to said photo-hardening resin; and    c) irradiating light onto said photo-hardening resin, thereby hardening said photo-hardening resin;    wherein said optical component is fixed to said photo-hardening resin when said photo-hardening resin is hardened in step (c).    
     
     
         14 . A method of fabrication of an optical element according to any one of  claims 1  to  5 , wherein said channel for optical waveguide in said substrate is formed in a integrated manner using a mold having protrusion and recess in the surface thereof.  
     
     
         15 . A method of fabrication of an optical element according to  claim 6  or  7 , wherein the protrusion and recess in said substrate of said optical element is formed in a integrated manner using a mold having protrusion and recess in the surface thereof.  
     
     
         16 . An optical element comprising: 
 a substrate having or not having a channel for an optical waveguide; and    a material which has a refractive index higher than that of said substrate and is filled in said channel for optical waveguide or is disposed on said substrate;    wherein the refractive index in a part of said material is substantially continuously monotone increasing or decreasing in the direction of light propagation.    
     
     
         17 . An optical element comprising: 
 a substrate having a channel for an optical waveguide; and    a material which has a refractive index higher than that of said substrate and is filled in said channel for optical waveguide or is disposed on said substrate;    wherein the refractive index in a part of said material varies substantially periodically in a direction substantially perpendicular to a direction of light propagation.