Spot-size conversion using uniform waveguide sections for efficient laser-fiber coupling

Author

Wongcharoen, T. ; Rahman, B.M.A. ; Rajarajan, M. ; Grattan, K.T.V.

Author_Institution

Bangkok Univ., Thailand

Volume

19

Issue

5

fYear

2001

fDate

5/1/2001 12:00:00 AM

Firstpage

708

Lastpage

716

Abstract

Using numerically simulated results, it is shown that an efficient laser-to-fiber coupling is possible by incorporating a uniform spot-size converter (SSC) with two nonidentical but phase matched optical waveguides. Using a “diluted” waveguide with a low index contrast, the power coupling loss can be significantly reduced from 10.4 dB to only 1.15 dB and at the same time 1.0 dB alignment tolerances can also be improved to achieve ±1.8 μm. Besides the improved coupling, the beam divergence of the far-field is also reduced considerably to 9°, accompanied by a significant lowering of the reflected power from the fiber interface

Keywords

integrated optics; laser beams; optical couplers; optical design techniques; optical fibre couplers; optical waveguide theory; 1.15 dB; 10.4 dB; alignment tolerances; diluted waveguide; far-field divergence; fiber interface; laser-fiber coupling; laser-to-fiber coupling; low index contrast; nonidentical phase matched optical waveguides; numerically simulated results; power coupling loss; reflected power; spot-size conversion; uniform spot-size converter; uniform waveguide sections; Costs; Integrated optics; Optical beams; Optical coupling; Optical devices; Optical fiber couplers; Optical fiber devices; Optical losses; Optical waveguides; Waveguide lasers;

fLanguage

English

Journal_Title

Lightwave Technology, Journal of

Publisher

ieee

ISSN

0733-8724

Type

jour

DOI

10.1109/50.923484

Filename

923484