title: Twin-rainbow metrology. I. Measurement of the thickness of a thin liquid film draining under gravity.
abstract: We describe twin-rainbow metrology, a new optical technique used to measure the thickness of thin films in a cylindrical geometry. We also present an application of the technique: measurement of the thickness of a Newtonian fluid draining under gravity. We compare these measurements with fluid mechanics models.
authors.affiliation: Department of Physics, St. Mary's College of Maryland, 18952 East Fisher Road, St. Mary's City, Maryland 20686, USA. cladler@smcm.edu
authors.forename: Charles L
authors.initials: CL
authors.lastname: Adler
authors.forename: James A
authors.initials: JA
authors.lastname: Lock
authors.forename: Ian P
authors.initials: IP
authors.lastname: Rafferty
authors.forename: Wayne
authors.initials: W
authors.lastname: Hickok