A special designed fiber with double layers of cores was investigated theoretically and experimentally. This fiber is widely used in astronomy to transform light from the telescope to the optical spectrum analyzer. The refractive index profile of this fiber was measured firstly. The testing result showed that the fiber has three layers of refractive index. A special layer of the highest refractive index is between the uniform general fiber core and the general low-refractive-index fiber cladding. This highest layer has higher local numeric aperture (NA), which can absorb more light when the incidence angle is little larger. A series of experiments have been done to prove that the NA is larger than normal fibers due to the higher-index layer. Two special incidence angles were measured respect to uniform and circle mode pattern.

Date Published: 28 November 2011
PDF: 6 pages
Proc. SPIE 8202, 2011 International Conference on Optical Instruments and Technology: Solid State Lighting and Display Technologies, Holography, Speckle Pattern Interferometry, and Micro/Nano Manufacturing and Metrology, 82020P (28 November 2011); doi: 10.1117/12.907232

Published in SPIE Proceedings Vol. 8202:
2011 International Conference on Optical Instruments and Technology: Solid State Lighting and Display Technologies, Holography, Speckle Pattern Interferometry, and Micro/Nano Manufacturing and Metrology
Hoi Sing Kwok; Fengzhou Fang; Lian Xiang Yang; Chongxiu Yu; Albert A. Weckenmann; Yanbing Hou; Jinxue Wang; Ji Zhao; Jinxue Wang; Peter Zeppenfeld; Boyu Ding; Boyu Ding; Liquan Dong; Liquan Dong; Jack K. Luo; Boyu Ding; Liquan Dong; Jinxue Wang, Editor(s)