title: Infrared optical sensor for measuring internal interfacial wave motions.
abstract: The absorption of infrared energy is used to infer internal interfacial displacements. The probe consists of an infrared emitting diode, operated in a pulsed mode, which projects a collimated beam of radiation across a fluid interface onto a silicon photodiode detector. The output of the diode feeds an amplifier and a sample-and-hold circuit. Through multiplexing, the electronics are capable of handling up to eight probes. The infrared sensor has a sensitivity of about 1 V/cm, and it may easily be used to resolve wave motions as small as 0.01 mm.
authors.affiliation: TRW Defense and Space Systems Group, Redondo Beach, California 90278.
authors.forename: C G
authors.initials: CG
authors.lastname: Koop
authors.forename: H
authors.initials: H
authors.lastname: Rungaldier
authors.forename: J D
authors.initials: JD
authors.lastname: Sherman