The Use of Fiber-Optics for TAP-NDE.

Thermal-Acousto-Photonic Nondestructive Evaluation (TAP-NDE) is a powerful new fiber optic based for the ultrasonic evaluation of flaws in structures and components. In this technique, pulses of laser light may be guided through a fiber optic probe to excite acoustic waves required for nondestructive interrogation. Alternatively, fiber optic interferometry may be used to detect the response of a structure subjected to acoustic wave excitation by either conventional or thermal-acoustic means. This paper describes improvements made in the detection phase of TAP-NDE by incorporating a bidirectional optical fiber coupler and PC-based signal analysis.