title: General formula for coupling-loss characterization of single-mode fiber collimators by use of gradient-index rod lenses.
abstract: A general formula for determining the coupling loss between two single-mode fiber collimators with the simultaneous existence of separation, lateral offset and angular tilt misalignments, and spot-size mismatch is theoretically derived by use of the Gaussian field approximation. Based on this general formula, the formulas for coupling losses that are due to the misalignment of insert separation, lateral offset, and angular tilt are given. The formula for the coupling loss that is due to Gaussian spot-size mismatch of two single-mode collimators is also given. Good agreement between these formulas and experimental results is demonstrated with gradient-index rod lens-based fiber collimators operating in the 1300-nm band.
authors.affiliation: Center for Research and Education in Optics and Lasers and the School of Optics, University of Central Florida, PO Box 162700, 4000 Central Florida Boulevard, Orlando, Florida 32816-2700, USA. shyuan@chorumtech.com
authors.forename: S
authors.initials: S
authors.lastname: Yuan
authors.forename: N A
authors.initials: NA
authors.lastname: Riza