<title>Smart-structure interface issues and their resolution: Bragg grating laser sensors and the "optical synapse"</title>

Abstract

Smart structure technology could revolutionize engineering by the 21st Century. Improvements in safety, reductions in cost, and enhancement of the environment are some of the expected benefits of this technology. A major impediment to the implementation of this technology in practical structures is going to be extracting the optical information from the structurally integrated sensing system. The answer to this problem lies in: demodulating, processing, and multiplexing the raw optical data from an array of sensors and transmitting these data from the structure in a single channel by means of an unobtrusive optoelectronic interface that is part of the structure. The single output channel from this optoelectronic smart structure interface could take several user-friendly forms, the most versatile involves free- space propagation and leads to the `optical synapse' concept. We have demonstrated that intracore Bragg grating laser sensors could form the basis of an OSSI and have shown that optical multiplexing is possible in the case of Bragg grating fiber laser sensors.