Regular papers

Observing cross-sectional images and averaged optical patterns of photonic crystal fibers using partially incoherent laser light

¹ Department of Electrophysics, National Chiayi University, Chiayi 60004, Taiwan
² Graduate Institute of Optoelectronics and Solid State Electronics, National Chiayi University, Chiayi 60004, Taiwan

^* fwsheu@mail.ncyu.edu.tw

Received: 30 July 2012
Revised: 19 October 2012
Revised: 22 December 2012

Abstract

We couple the coherent laser light and the partially incoherent laser light into the photonic crystal fibers, respectively, and compare the observed fiber cross-sectional images. Lower coherence light can indeed help us obtain higher-quality and uniform cross-sectional images on the fiber output endfaces. We have observed rather unique and clear averaged optical mode patterns within the microstructures of a silica-air index-guiding solid-core photonic crystal fiber, which might be due to the stress-induced refractive-index inhomogeneity formed therein during the fiber manufacturing process. The experimental results are also compared with those images taken by other light sources or imaging systems. Besides, we successfully achieve capturing consecutively the various near-field averaged optical patterns of the solid-core photonic crystal fiber using this single-wavelength partially incoherent laser light imaging system.