Blue Road Research Home
 

Overview

Blue Road Research has a rapidly growing portfolio of patents on advanced fiber sensors for multi-axis strain, pressure, temperature, corrosion and distributed sensing applications. In addition, Blue Road Research has both license and sublicensing rights to 13 McDonnell Douglas Patents and Patent Applications.

Nonexclusive or Exclusive Licenses are Possible

The following US Patents related to fiber optic sensors and smart structures are available from Blue Road Research on a nonexclusive basis and on an exclusive basis for designated market segments.

  • 5,591,965  Multiparameter Sensor System Using a Multiple Grating Fiber Optic Birefringent Fiber, by Eric Udd, January 7, 1997. This patent covers the usage of dual overlaid fiber gratings written onto birefringent fiber to measure environmental effects, notably three dimensional strain and temperature. It is one of the foundation patents for work on multi-parameter fiber grating sensors designed to measure more than one parameter simultaneously at a single location.


  • 5,636,021  Sagnac/Michelson Distributed Sensing Systems, by Eric Udd, June 3, 1997. This patent covers distributed sensing methods using fiber grating integrated into a Sagnac loop. It is describe methods for integrated strain and distributed measurements as well as local measurements of strain.


  • 5,646,401  Fiber Optic Grating and Etalon Sensor Systems, by Eric Udd, July 8, 1997. This patent covers a potentially very low cost method of measuring fiber grating spectral output and in turn measure environmental effects.


  • 5,828,059  Transverse Strain Measurements Using Fiber Optic Grating Based Sensors, by Eric Udd, October 27, 1998. Extensions, refinements and experimental data obtained to support the measurement of pressure using transverse fiber grating strain sensors are covered in this fundamental patent.


  • 5,841,131  Fiber Optic Pressure Transducers and Pressure Sensing System Incorporating Same, by Robert Schroeder and Eric Udd, November 24, 1998. This patent covers the usage of sidehole fiber to measure transverse strains and pressure. It discusses techniques to multiplex these sensors and a number of specific configurations highly directed toward pressure measurements.


  • 5,869,835  Asymmetric Fiber Optic Grating Sensor, by Eric Udd, February 9, 1999. This patent covers aspects of transverse strain sensing using fiber optic grating sensors that were not covered by earlier patents including the usage of asymmetric structures to facilitate usage, insertion into structures and packages and enhance performance.


  • 6,144,026  Fiber Optic Grating Corrosion and Chemical Sensor, by Eric Udd, Eric Haugse and Angela Trego, November 7, 2000. This patent covers the usage of transversely loaded fiber grating sensors to measure corrosion and chemicals as they are unloaded due to corrosion and chemical action.


  • 6,218,661  Methods and Apparatus for Mechanically Enhancing the Sensitivity of Transversely Loaded Fiber Optic Sensors, by Robert Schroeder, Tsutomu Yamate, Rogerio Ramos, Raghu Madhavan and Eric Udd, April 17, 2001. This patent addresses a series of packages that are designed to provide transverse load to a fiber grating strain sensor that is proportional to pressure.


  • 6,335,524  High Speed Demodulation Systems for Fiber Optic Grating Sensors, by Eric Udd and Andreas Weisshaar, January 1, 2002. The two principal areas addressed by this patent involve (1) the usage of techniques to multiplex and operate fiber grating strain sensors at very high speeds and (2) the ability to use multi-parameter fiber grating sensors to measure two or three parameters simultaneously in an optimal fashion.


  • 6,363,180  Methods and Apparatus for Enhancing Dynamic Range, Sensitivity, Accuracy, and Resolution in Fiber Optic Sensor Systems, by Tsutomu Yamate, Robert Schroeder, Rogerio Ramos and Eric Udd, March 26, 2002. This patent is targeted to address the use of polarization control methods to interrogate multi-parameter fiber grating sensors such as those designed to measure pressure and temperature simultaneously.


  • 6,459,486  Single Fiber Sagnac Sensing System, by Eric Udd and Michael Morrell, October 1, 2002. The focus of this patent is on a single fiber Sagnac system that may be used to measure and localize time varying events. It has the advantage of having a sensing region consisting of a single optical fiber operating in a reflective mode.


  • 6,600,149  Fiber Grating Environmental Sensing System, by Whitten Schulz and Eric Udd, July 29, 2003. This patent covers mechanically tunable fiber grating filters that can be used to support fiber grating read out units and other spectral interrogation applications.


  • 6,683,297  Fiber Grating Moisture and Chemical Sensing System, by Whitten Schulz and Eric Udd, January 27, 2004. This patent addresses a series of fiber grating sensor configurations designed to measure moisture and chemical content.


  • 6,690,890  Single Fiber Sagnac Interferometer Based Secure Communication System, by Eric Udd, Michael Morrell and Peter Snawerdt, III, February 10, 2004. This patent covers a Sagnac interferometer based secure communication system that is designed to operate over a single fiber line.


  • 6,756,580  Fiber Grating Bond Joint Health Monitoring System, by Whitten Schulz and Eric Udd, June 29, 2004. This patent covers the application of multi-axis fiber grating strain sensors to monitoring breakdown of adhesive joints.


Patents Allowed, Pending and Provisional Patents

Blue Road Research, at any time, has several patent and provisional patent applications pending on fiber optic sensor technology.

Nonexclusive Licences

Blue Road Research has the right to nonexclusively license 13 patents that belong to Boeing/McDonnell Douglas. The following U.S. Patents are available from Blue Road Research on a nonexclusive basis.

  • 4,787,741  Fiber Optic Sensor, by Eric Udd, Ronald Michael, Steve Watanabe, John Paul Theriault and Richard Cahill, November 29, 1988. This patent covers the usage of the Sagnac interferometer to implement long gauge length strain sensors.


  • 4,789,241  Optical Fiber Sensing Systems Having Acoustical Optical Deflection and Modulation Devices, by Ronald Michael, Eric Udd and Richard Cahill, December 6, 1988. The Sagnac interferometer can be used to measure wavelength and fiber dispersion properties that are useful as stand-alone instruments and also for supporting fiber gyroscopes.


  • 4,834,493  Method of Terminating an Optical Fiber, by Eric Udd and Ray Wagoner, May 30, 1989. This patent covers a series of ways to terminate a fiber end to avoid back reflection into a fiber system.


  • 4,875,775  Reciprocally Switched Four Modulator System, by Ronald Michael, Eric Udd and Richard Cahill, October 24, 1989. This patent covers the usage of a switched acousto-optic modulator-based system configured to greatly reduce bias drift and provide wavelength measurement capabilities.


  • 4,898,468  Sagnac Distributed Sensor, by Eric Udd, February 6, 1990. The first in a series of patents describing the usage of the Sagnac interferometer as a distributed sensor.


  • 4,976,507  Sagnac Distributed Sensor, by Eric Udd, December 10, 1990. This is a divisional case of 4,898,468.


  • 5,046,848  Fiber Optic Detection System Using a Sagnac Interferometer, by Eric Udd, September 10, 1991. This Sagnac-distributed sensor case combines a Sagnac interferometer sensor with an RF generated linear signal to provide information on location and amplitude of a time-varying event.


  • 5,118,931 Fiber Optic Microbending Sensor Arrays Including Microbend Sensors Sensitive over Different Bands of Wavelengths of Light, by Eric Udd and John Paul Theriault, June 2, 1992. This patent covers a method to multiplex a series of microbend sensors.


  • 5,380,995  Fiber Optic Grating Sensor Systems for Sensing Environmental Effects, by Eric Udd and Tim Clark, January 10, 1995. This patent covers the usage of fiber grating filters to demodulate fiber grating sensors. Blue Road Research has based a series of demodulator products being developed under this patent and extensions to be filed.


  • 5,397,891  Sensor Systems Employing Optical Fiber Gratings, by Eric Udd and Tim Clark, March 14, 1995. This patent covers the usage of fiber etalons to demodulate fiber gratings essentially extending the prior case. The use of fiber etalons is probably the most extensively utilized technique for demodulating fiber gratings with moderate to high precision.


  • 5,402,231  Distributed Sagnac Sensor Systems, by Eric Udd, March 28, 1995. Describes interleaving Sagnac interferometers to form a distributed sensor system.


  • 5,446,533  Fiber Optic Measuring Apparatus and Method, by Eric Udd and John Paul Theriault, August 29, 1995. This patent describes how the Sagnac interferometer may be used to measure unknown lengths of optical fiber very accurately.


  • 5,627,927  Fiber With Multiple Overlapping Gratings, by Eric Udd, May 6, 1997. This patent covers some special cases of overlaid and angled fiber gratings.