Abstract: A laser ultrasonic inspection apparatus and method which enables remote sensing of thickness, hardness, temperature and/or internal defect detection is disclosed. A laser generator impinges a workpiece with light for generating a thermo-elastic acoustic reaction in a workpiece. A probe laser impinges the workpiece with an annularly-shaped probe light for interaction with the acoustic signal in the workpiece resulting in a modulated return beam. A photodetector having a sensitive region for detecting an annularly-shaped fringe pattern generated by an interaction of a reference signal and with the modulated return beam at said sensitive region.

Abstract: The present invention provides a method and apparatus for extending a zone routing protocol. The invention is configured to provide a robust scalable framework for routing data in wireless ad-hoc networks when unidirectional links 210 are present. When the reverse path from a destination node (the tail) of a unidirectional link 210 to the originating node (the head) of the link is beyond a designated length, the invention is configured to revert to an on-demand search mechanism. The on-demand search mechanism recursively attempts to build a path to the destination 206 by recognizing nodes that have a route to the destination.