title: Nondestructive measurement of refractive index profile for holey fiber preforms.
abstract: A non-destructive technique is presented to determine the refractive index profile of holey fiber preforms. The holes are filled with index matching oil and the holey preform deflection data is measured. An improved optical path-length formula and back projection method is used to reconstruct the two-dimensional filled holey fiber preform refractive index distribution.
authors.forename: Yucheng
authors.initials: Y
authors.lastname: Zhao
authors.forename: Katja
authors.initials: K
authors.lastname: Lyytikainen
authors.forename: Martijn
authors.initials: M
authors.lastname: van Eijkelenborg
authors.forename: Simon
authors.initials: S
authors.lastname: Fleming