WO1998032199B1

WO1998032199B1 - Optical waveguide amplifier

Info

Publication number: WO1998032199B1
Application number: PCT/US1998/001126
Authority: WO
Filing date: 1998-01-20
Publication date: 1998-09-11

Abstract

A side-polished fiber/overlay waveguide architecture and process for non-invasively implementing an optical amplifier are provided for an optical communications system. A 'channel' overlay waveguide is employed to constrain for amplification optical energy evanescently coupled to the overlay waveguide from the side-polished optical fiber. One of two amplification methods can be employed. The first involves inducing stimulated emission with the overlay waveguide and the second uses a second order, non-linear frequency conversion to down-convert a high-power, short-wavelength pump signal into the waveguide to amplify the optical energy coupled thereto. Amplification of optical energy in the channel overlay waveguide can be established within a single beat length of evanescent removal to evanescent return of the optical energy to the side-polished fiber optic.

Claims

32199 PCT/US98/01126

AMENDED CLAIMS

[received by the International Bureau on 24 July 1998 (24.07.98); original claims 17 and 18 amended; remaining claims unchanged (2 pages)]

propagating in the side-polished fiber waveguide without degrading optical signal integrity.

1 . The compound waveguide of claim 13 , wherein said channel overlay waveguide exhibits optical fluorescence, and said stimulated emissions means comprises a laser pump for pumping energy into said channel overlay waveguide to produce a stimulated emissions bandwidth, and wherein said optical energy coupled to said channel overlay waveguide has a wavelength within said stimulated emissions bandwidth.

15. The compound waveguide of claim 14, wherein said channel overlay waveguide comprises one of a rare-earth doped crystal, a rare-earth doped glass, a rare-earth based film, a polymer, and an optically/electrically pumped semiconductor.

16. The compound waveguide of claim 13, wherein said channel overlay waveguide comprises a neodymiurn- doped material .

17. An optical coupler comprising:

a first waveguide for propagating an optical signal along a propagation axis;

a second waveguide comprising a channel overlay waveguide positioned in optical proximity to a portion of the first waveguide, said second waveguide having a propagation axis aligned with the propagation axis of the first waveguide, and a coupling surface through which optical energy is coupled to or from the optical signal propagating in the first waveguide, and wherein said second waveguide is configured such that only one oscillation of optical energy from the optical signal occurs between the first waveguide and the second waveguide through said coupling surface; and

stimulated emissions means for amplifying optical energy in the second waveguide coupled thereto from the optical signal in the first waveguide during said one oscillation of said optical energy between the first waveguide and the second waveguide.

18. The optical coupler of claim 17, wherein said portion of said first waveguide comprises a side-polished portion of said first waveguide, and wherein said second waveguide comprising said channel overlay waveguide restrains optical energy coupled to said second waveguide within a predefined area orthogonal to said propagation axis of said second waveguide, said predefined area being disposed substantially only over said first waveguide.

19. The optical coupler of claim 17, wherein said second waveguide comprises one of a rare-earth doped crystal, a rare-earth doped glass, a rare-earth based deposited film, a polymer, and an optically/electrically pumped semiconductor.

20. The optical coupler of claim 17, wherein said second waveguide comprises a neodymium-doped material .

21. An optical amplifier for coupling to a side-polished fiber optic, said optical amplifier comprising: 49

STATEMENT UNDER ARTICLE 19

In substitute claim pages 42 & 43, claims 17 & 18 are amended. These amendments to the claims are made to recite that the second waveguide of independent claim 17 comprises a "channel overlay waveguide." It is respectfully submitted that the prior art characterization of the Panajotov article is incorrect to any extent deemed applicable to the amended claims presented herewith. The Panajotov article only describes slab waveguides, while the claims presented herein are directed to channel waveguides . Based upon this difference, all claims are believed patentable.