title: Real-time, frequency-translated holographic visualization of surface acoustic wave interactions with surface-breaking defects.
abstract: A real-time, frequency-translated holographic imaging system has been developed by use of bacteriorhodopsin film. The system provides a capability for imaging surface acoustic waves and has been utilized to detect and characterize surface-breaking defects through near-field ultrasonic scattering effects. Frequency-plane filtering was used to discriminate between ultrasonic standing-wave and near-field scattering features, dramatically enhancing the holographic visualization of the defect sites. A detailed description of the system is presented, along with representative holographic images showing the interaction of surface acoustic waves with surface-breaking cracks and small notches in aluminum and titanium substrates.
authors.forename: James L
authors.initials: JL
authors.lastname: Blackshire
authors.forename: Shamachary
authors.initials: S
authors.lastname: Sathish
authors.forename: Bradley D
authors.initials: BD
authors.lastname: Duncan
authors.forename: Mike
authors.initials: M
authors.lastname: Millard