Planar optical waveguides with planar optical elements

• US 5,612,171 A
• Filed: 02/13/1995
• Issued: 03/18/1997
• Est. Priority Date: 02/24/1992
• Status: Expired due to Term

• Current Assignee: Corning Incorporated
• Original Assignee: Corning Incorporated
• Inventors: Bhagavatula, Venkata A.
• Primary Examiner(s): McPherson, John A.
• Application Number:
  US08/387,976
• Time in Patent Office: 764 Days
• Field of Search: 430/321, 430/323, 430/4, 385/129, 385/14, 427/585, 427/167, 427/168, 216/24
• US Class Current: 430/321
• CPC Class Codes: G02B 6/122 Basic optical elements, e.g. light-guiding paths
• CPC Class Codes: G02B 6/2808 using a mixing element which evenly distributes an input signal over a number of outputs
• CPC Class Codes: G02B 6/2817 using reflective elements to split or combine optical signals

Abstract

A planar optical waveguide comprises a substrate 1, a waveguide core layer 2, at least one planar optical element, wherein said planar optical element comprises at least one optically functional interface 3 which is adjacent to a cavity 4, and an overclad layer 5. The cavity enhances the optical characteristics of the planar optical element because of the substantial difference in the refractive index of the cavity as compared to the refractive index of said waveguide core layer.

Claims

1. A process for manufacturing planar optical waveguides, comprising

(a) forming a planar structure by combining a substrate having a first refractive index with at least one region of an optically transmitting material having a second refractive index which is different from said first refractive index;

(b) removing material from at least one portion of said planar structure using lithographic techniques to produce thereon, (i) preselected optical circuitry, and (ii) at least one planar optical element comprising at least one optically functional interface and at least one cavity having a width adjacent to said optically functional interface; and

(c) combining a region of additional material with said planar structure over at least one area where material has been removed, wherein said region of additional material does not alter said width of said at least one cavity adjacent to said optically functional interface, wherein said planar structure is heated and stretched prior to said removing step.

2. A process for manufacturing planar optical waveguides, comprising

(a) forming a planar structure by combining a substrate having a first refractive index with at least one region of an optically transmitting material having a second refractive index which is different from said first refractive index;

(b) removing material from at least one portion of said planar structure using lithographic techniques to produce thereon, (i) preselected optical circuitry, and (ii) at least one planar optical element comprising at least one optically functional interface and at least one cavity having a width adjacent to said optically functional interface; and

(c) combining a region of additional material with said planar structure over at least one area where material has been removed, wherein said region of additional material does not alter said width of said at least one cavity adjacent to said optically functional interface, wherein said region of additional material is applied using tape casting techniques.

3. A process for manufacturing planar optical waveguides, comprising

(a) forming a planar structure by combining a substrate having a first refractive index with at least one region of an optically transmitting material having a second refractive index which is different from said first refractive index;

(b) removing material from at least one portion of said planar structure using lithographic techniques to produce thereon, (i) preselected optical circuitry, and (ii) at least one planar optical element comprising at least one optically functional interface and at least one cavity having a width adjacent to said optically functional interface;

(c) combining a region of additional material with said planar structure over at least one area where material has been removed, wherein said region of additional material does not alter said width of said at least one cavity adjacent to said optically functional interface; and

(d) fusing said at least one region of optically transmitting material to said substrate at a first temperature and fusing said region of additional material to said planar structure at a second temperature, wherein the second temperature is substantially lower than the first temperature.

4. A process for manufacturing planar optical waveguides, comprising

(a) forming a planar structure by combining a substrate having a first refractive index with at least one region of an optically transmitting material having a second refractive index which is different from said first refractive index;

(b) removing material from at least one portion of said planar structure using lithographic techniques to produce thereon, (i) preselected optical circuitry, and (ii) at least one planar optical element comprising at least one optically functional interface and at least one cavity having a width adjacent to said optically functional interface; and

(c) combining a region of additional material with said planar structure over at least one area where material has been removed, wherein said region of additional material does not alter said width of said at least one cavity adjacent to said optically functional interface, wherein a layer of polymer material is applied over said at least one cavity before applying said region of additional material, wherein said layer of polymer material does not alter the width of said cavity adjacent to said optically functional interface; and

wherein said region of additional material is applied using low temperature, plasma-enhanced chemical vapor deposition techniques.