Robert Patrick Kenny

Loss and spectral control in fused tapered couplers

The loss and spectral characteristics of fused tapered coupiers depend, respectively, on the taper transition rate and on the size, shape, and length of the coupler waist region. We show how the choice of the fusing and tapering burner is critical in optimizing the behavior of three different coupler types: the single-wavelength splitter, the wavelength division multiplexer, and the wavelength-independent coupler.

Optomechanical actuator for adaptive optics

This study describes the development of a novel opto- mechanical actuator suitable for integration in all-optical smart systems. Its action relies on the out-of-plane thermo- mechanical deflection of a thin optical-acrylic membrane due to the absorption of radiation from a laser source. The response of the actuator can be adapted to suit different applications by coating the surfaces of the element with either fully or partially absorbing or reflective coatings. The transient and steady state opto-thermo-mechanical behavior of different element configurations has been modelled analytically and using finite element analysis. In simple actuator configurations, the dynamic response of the element can be represented by that of a linear first order system. These modelling and simulation procedures have been verified with experimental data and have been used to optimize different actuator designs. One of these opto- mechanical actuators has been employed as an active optical element in the realization of a novel all-optical interferometric device employing active drift compensation.

Fiber optic sensors for characterization of composite structural materials and structural monitoring

We present recent work on fiber optic sensor systems for structural element characterization and monitoring. One particular application area currently under study is the characterization and testing of pultruded composite beams. The motivation behind this project and current status is described. Fiber optic sensor systems to suit the application have been developed. In particular, the development of both AO tunable filter and all-fiber passive demodulation schemes for in-fiber Bragg grating sensors is described.