In-fiber reflection mode interferometer based on a long-period grating for external refractive-index measurement.
We present two novel schemes for refractometry based on a long-period fiber grating- (LPG-) based Michelson interferometer. These schemes are designed to overcome the measurement dependence of previously demonstrated LPG-based refractometry on the immersion depth. The first utilizes an unshielded LPG and the second, a shielded one. Both schemes were tested over a certain refractive-index range, and the measurement of glucose concentration in water was experimentally demonstrated. In addition, the temperature sensitivity of the two schemes is discussed.
Kim
Dae Woong
DW
Center for Photonics Technology, Bradley Department of Electrical and Computer Engineering, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24061-0111, USA. dakim1@vt.edu
Zhang
Yan
Y
Cooper
Kristie L
KL
Wang
Anbo
A