Planar waveguide with patterned cladding and method for producing same
Integrated optical waveguides and methods for the production thereof which have a patterned upper cladding with a defined opening to allow at least one side or at least one end of a light transmissive element to be air clad. The at least one side or at least one end is, for preference, a lens structure unitary with the waveguide or a bend. Also provided is a method of fabricating an optical waveguide with a patterned cladding.
1. An integrated optical waveguide comprising:
a substrate;
a light transmissive element disposed on the substrate and comprising a waveguide with a bend along a length thereof; and
an upper cladding having a pattern which provides at least one region in the bend in which the light transmissive element has an air clad side surface and a top portion of the light transmissive element is air clad, and where the upper cladding comprises a polymeric material; and
wherein the pattern of the upper cladding is different from that of the light transmissive element in the region of the bend.
2. An integrated optical waveguide according to claim 1 , additionally comprising a lower cladding layer between the substrate and the light transmissive element.
3. An integrated optical waveguide according to claim 1 , wherein the air clad side surface is on an outer side of the bend.
4. An integrated optical waveguide according to claim 3 , wherein the waveguide further has another air clad side surface on an inner side of the bend.
5. An integrated optical waveguide according to claim 1 , wherein a portion of the upper cladding matches a portion of the light transmissive element.
6. An integrated optical waveguide according to claim 1 , wherein the polymeric material comprises a thermally curable polymer.
7. An integrated optical waveguide according to claim 6 , wherein the thermally curable polymer is a siloxane polymer.
8. An integrated optical waveguide according to claim 1 , wherein the polymeric material comprises a polymer curable by actinic radiation.
9. An integrated optical waveguide according to claim 8 , wherein the actinic radiation is ultraviolet light.
10. An integrated optical waveguide according to claim 8 , wherein the polymeric material is a siloxane polymer.
11. An integrated optical waveguide according to claim 1 , wherein the upper cladding is patterned by selective curing with a patterned heat source and uncured material dissolved with a solvent, whereby cured material is insoluble in the solvent.
12. An integrated optical waveguide according to claim 1 , wherein the upper cladding is patterned by selective curing with a patterned source of ultraviolet light and uncured material dissolved with a solvent, whereby cured material is insoluble in the solvent.
13. An integrated optical waveguide according to claim 1 , wherein the substrate comprises silicon, quartz, fused silica, glass, or a polymeric material.
14. An integrated optical waveguide according to claim 13 , wherein the polymeric material comprises an acrylate, Perspex, polymethylmethacrylate, polycarbonate, polyester, polyethyleneterephthalate or PET.
15. An integrated optical waveguide according to claim 2 , wherein the lower cladding layer and light transmissive element comprise materials selected from the group consisting of polymeric materials, glass and semiconductors.
16. An integrated optical waveguide according to claim 15 , wherein the polymeric materials comprise polymers curable by actinic radiation.
17. An integrated optical waveguide according to claim 16 , wherein the actinic radiation is ultraviolet light.
18. An integrated optical waveguide according to claim 17 , wherein the polymeric material is a siloxane polymer.