The Charles Stark Draper Laboratory, Inc.

USA As Represented by Secretary of the Navy

William P Kelleher

Stephen P Smith

Richard E Stoner

Reinhardt Leon Willig

Donald C Fyler

Jacques P Govignon

A hysteresis-start permanent magnet rotor having a non-magnetic rotor shaft, a permanent magnet rigidly attached to a center portion of the non-magnetic rotor shaft, a non-magnetic spacer on each side of the permanent magnet, each non-magnetic spacer rigidly attached to the non-magnetic rotor shaft, to form a non-magnetic spacer-permanent magnet-non-magnetic spacer combination, a hysteresis ring on each side of the non-magnetic spacer-permanent magnet-non-magnetic spacer combination, each hysteresis ring being rigidly attached to the non-magnetic rotor shaft. A stator-segment is around each of the hysteresis rings and a stator-segment is around the permanent magnet, each stator-segment separated from a next stator-segment by a non-magnetic spacer.

Hysteresis-start permanent magnet motor

A fluorescence detection system includes a photonic band gap structure. An internal surface of the photonic band gap structure defines a core region, and is coated with a film formed of conjugated polymer molecules. The core region is filled with a sample fluid or gas having a plurality of either chemical or biological analytes dispersed therein. An optical source generates excitation light directed to the sample fluid. In response, a binding event between a bacterium or chemical species in the fluid or gas and one or more of the conjugated polymer molecules generates a fluorescent signal whose wavelength falls within the photonic band gap. The fluorescent signal is guided through said core region by resonant reflections, and is guided onto a detector. A plurality of photonic band gap structures may be combined so as to form a biosensor array.

Fluorescence detection system including a photonic band gap structure

A photonic crystal interferometric optical gyroscope system including a light source for providing a primary beam of light, a photonic crystal sensing coil having a rotational axis, and a beam controlling device configured to split the primary beam into first and second counter-propagating beams in the photonic crystal sensing coil and configured to direct return of the counter-propagating beams wherein the power of the returning counter-propagating beams represents the phase shift between the counter-propagating beams and is indicative of the rate of rotation of the coil about the rotational axis.

Photonic crystal interferometric fiber optical gyroscope system

An optical accelerometer for detecting an acceleration of a proof mass includes a source of optical radiation for generating a pair of beams of output radiation. The pair of beams of optical radiation exerts radiation pressure on the proof mass, so as to maintain the proof mass in an equilibrium position along a sensing axis. A position detecting system detects a displacement from the equilibrium position of the proof mass along the sensing axis in response to an inertial force acting on the proof mass. A modulator adjusts the intensity of each one of the pair of beams, so as to restore the proof mass to the equilibrium position along the sensing axis. The difference in the adjusted intensities of each one of the pair of beams is representative of the acceleration, resulting from the inertial force, of the proof mass along the sensing axis.

Optically rebalanced accelerometer

The invention relates to a method and system for wavelength stabilization of a broadband optical source. The method and system are based on utilizing an optical power divider to generate two optical signals for each of the broadband source and a reference wavelength source. The difference in the power ratio of the two optical signals derived from the broadband source and the power ratio of the two optical signals derived from the reference wavelength source is determined. Because the power ratios are similarly affected by component aging and changes in environmental factors such as temperature and incident radiation, the difference in the power ratios can be used to adjust the wavelength of the broadband source so that its center wavelength is stabilized to the center wavelength of the reference source.

Growing community of inventors

Acton, MA, United States of America

William P Kelleher