Technology

Key Innovations from IFOS

IFOS develops photonic computing, sensing, and signal processing technologies. The advancement of these technologies has yielded a basis for industrial products now available for purchase via Opterro, Inc.

  • Fiber Bragg grating (FBG)-based wavelength-division multiplexed sensing technology platform: i*Sense®
  • Raman scattering in optical fibers for distributed temperature sensing: r*Sense®
  • Brillouin scattering in optical fibers for distributed temperature and strain sensing: b*Sense
  • Fabry-Perot interferometry (FPI) multi-functional sensors: FPI*Sense™
  • Interferometric fiber-optic gyroscopic (I-FOG) for tracking and navigation: g*Sense®
  • Photonic computing modules and subsystems

i*Sense® family of FBG Interrogators

The most comprehensive collection of solution for optical sensing of high-value assets are available commercially from Opterro, Inc.

i*Sense® FBG Interrogation Principle and Architecture

r*Sense® Raman Distributed Temperature Sensing (R-DTS)

The r*Sense® system was incorporated into IFOS’s technology portfolio during IFOS’s its 2006 acquisition of VC-funded Oluma, Inc in Carlsbad, CA. This system has demonstrated temperature measurement up to 200°C in oil and gas applications; although fire detection can be achieved at temperatures below 100°C in standard operating conditions, higher temperature measurement capability could be valuable during battlefield damage assessment in providing crew and engineers an understanding of the structural integrity of ship components at prolonged high temperatures.

In contrast to FBG sensing, where sensors are discrete sensing ‘points’ up to several millimeters long located at chosen positions along an optical fiber, the r*Sense® R-DTS system consists of a whole fiber length (up to kilometers long), which acts as a sensor along which a temperature is measured. The R-DTS sensing system uses a narrow-band laser source that launches light through the fiber. The interaction of the light with the fused silica in the fiber causes light to scatter backwards along the fiber. A typical reflected spectrum contains Rayleigh, Brillouin, and Raman components. The r*Sense® system exploits the Raman peaks; specifically, the intensity of the anti-Stokes Raman peak is dependent on temperature and therefore used to infer temperature change along the fiber. Raman sensing is not sensitive to strain, and responds only to temperature.

The optical fiber configuration used for Raman sensing is different from that used for FBG sensing; strain monitoring and fire detection will each use their own fiber and supporting interrogator. This allows for greater flexibility in routing for required sensing locations. For example, shipboard electrical conduits for which strain information is not necessary would benefit greatly from having distributed fire detection along the length of electrical wiring to detect electrical fires.
The IFOS r*Sense® system was originally developed for harsh downhole oil and gas applications and has been field-proven in such applications, meaning that the technology risk is relatively low. In addition to oil and gas applications, the IFOS r*Sense® technology has been used to demonstrate feasibility of fire detection in collaboration with the Department of Homeland Security.

The IFOS team has a proven track record in developing low-SWaP-C systems for harsh environments to sense shock, vibration, temperatures, and radiation. IFOS’s FOG development programs have already resulted in more compact, less expensive, higher bandwidth, and lower noise devices. IFOS FOGs offer performance that approaches the high-end, tactical-grade performance levels for guidance, navigation, and control (GN&C) instrumentation needed for deployment in defense and space applications.