Optical waveguide having a weakly-confining waveguide section and a strongly-confining waveguide section optically coupled by a tapered neck

• US 6,571,039 B1
• Filed: 11/22/2000
• Issued: 05/27/2003
• Est. Priority Date: 11/23/1999
• Status: Expired due to Fees

• Current Assignee: Enablence, Inc. (Enablence Technologies Incorporated)
• Original Assignee: LNL Technologies, Inc.
• Inventors: Youtsey, Christopher T., Al-hemyari, Kadhair
• Primary Examiner(s): Palmer, Phan T. H.
• Application Number:
  US09/718,954
• Time in Patent Office: 916 Days
• Field of Search: 385/14, 385/28-32, 385/37, 385/123, 385/40-43, 385/50, 385/51, 385/130-132
• US Class Current: 385/43
• CPC Class Codes: G02B 2006/12195 Tapering
• CPC Class Codes: G02B 6/1228 Tapered waveguides, e.g. integrated spot-size transformers for coupling with fibres G02B6/305
• CPC Class Codes: G02B 6/26 Optical coupling means G02B6/36, G02B6/42 take precedence
• CPC Class Codes: G02B 6/305 and having an integrated mode-size expanding section, e.g. tapered waveguide

Abstract

An optical waveguide includes a first waveguide section providing weak confinement of an optical signal in a direction generally transverse to its propagation direction, a second waveguide section providing strong confinement of the optical signal in all directions relative to the propagation direction, a tapered neck between the first and second waveguide sections to optically couple those waveguide sections, and a core defined through the first and second waveguide sections and tapered neck, and through which the optical signal may propagate in the propagation direction. A method for making such an optical waveguide.

Claims

1. An optical waveguide through which an optical signal may propagate in a propagation direction and along an optical path, said waveguide comprising:

a first waveguide section providing weak confinement of the optical signal in a direction generally transverse to the propagation direction;

a second waveguide section providing strong confinement of the optical signal in all directions relative to the propagation direction;

a tapered neck between said first and said second waveguide sections to optically couple said first and said second waveguide sections; and

a core defined through said first and said second waveguide sections, said tapered neck, and through which the optical signal may propagate in the propagation direction.

2. A waveguide according to claim 1, wherein said tappered neck has a width that appears at a first rate.

3. A waveguide according to claim 2, wherein said tapered neck has a thickness that tapers at a second rate.

4. A waveguide according to claim 3, wherein said first and said second rates are substantially constant.

5. A waveguide according to claim 1, wherein said first waveguide section is at least approximately 2 μ

m wide.

6. A waveguide according to claim 1, wherein said second waveguide section is not more than approximately 1 μ

m wide.

7. A waveguide according to claim 1, wherein said tapered neck simultaneously tapers in both a width and a thickness.

8. A waveguide according to claim 1, wherein said first waveguide section is a strip waveguide.

9. A waveguide according to claim 1, wherein said second waveguide section is a strip waveguide.

10. A waveguide according to claim 1, wherein said tapered neck had a width, a thickness, and a length, wherein said width decreases as said thickness increases over said length.

11. A waveguide according to claim 1, wherein at least one of said first and said second waveguide sections is a single-mode waveguide.

12. A waveguide according to claim 1, wherein said first waveguide section, said second waveguide section, and said tapered neck are unitarily formed on a substrate.