An external-cavity laser, suitable for producing a coherent and highly-polarized optical emission, particularly at communication wavelengths, is enabled by a novel wavelength selective element based on a waveguide technology that supports a long-range plasmons polariton mode. These external-cavity lasers leverage the inherent properties of the novel wavelength selective elements, which are materials agnostic, providing easier means for tunability, laser stability, and low cost of fabrication, high output power and a highly polarized output. Tunable versions are also disclosed.
CROSS-REFERENCE TO RELATED APPLICATIONS
This invention claims priority from U.S. Provisional patent application No. 60/450,717 file date Dec. 20, 2002 the contents of which are incorporated herein by reference.
A system and method relating to the measuring of torque in a rotating shaft is provided. An optical torque sensing system comprises a rotating shaft, wherein a sleeve of photo-elastic material overlays a portion of the shaft. A light emitting component delivers light into the photo-elastic material, wherein the light delivered by the light emitting component is directed through the photo-elastic material along an axis of the rotating shaft. A capturing component captures the light that exits the photo-elastic material. The exiting light comprises fringe pattern data, and a computing system computes torsion strain of the shaft based at least in part on the fringe pattern information