title: Detection of subsurface defects using phase conjugate waves and forced vibration.
abstract: In four-wave mixing in BSO crystal, a periodic forced vibration is applied to both the object under test and the standard object to provide signal and reference waves, respectively. The system images subsurface defects of the test object by converting the difference of vibration between the test and the standard objects into image intensity. The principle and basic experimental results are given.
authors.forename: T
authors.initials: T
authors.lastname: Sato
authors.forename: Y
authors.initials: Y
authors.lastname: Odai
authors.forename: O
authors.initials: O
authors.lastname: Ikeda