title: Development of an in-fiber white-light interferometric distance sensor for absolute measurement of arbitrary small distances.
abstract: The fabrication, implementation, and evaluation of an in-fiber white-light interferometric distance sensor that is capable of measuring the absolute value of an arbitrary small distance are presented. Taking advantage of the mode-coupling effect of a long-period fiber grating, an additional cavity distance is added to the optical path difference of the distance sensor; therefore, it can generate a sufficient number of fringes for distance demodulation even if the free-space cavity distance is very small. It is experimentally verified that the distance sensor is capable of measuring small distances that are beyond the capability of a Fabry-Perot interferometric distance sensor.
authors.affiliation: Mechanical and Aerospace Engineering Department, University of Texas at Arlington, Arlington, TX 76019, USA.
authors.forename: Ayan
authors.initials: A
authors.lastname: Majumdar
authors.forename: Haiying
authors.initials: H
authors.lastname: Huang