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.
© 2003 Optical Society of America
Charles L. Adler, James A. Lock, Ian P. Rafferty, and Wayne Hickok, "Twin-Rainbow Metrology. I. Measurement of the Thickness of a Thin Liquid Film Draining Under Gravity," Appl. Opt. 42, 6584-6594 (2003)