Harsh environments minimally invasive optical sensing technique for extreme temperatures: 1000 degrees C and approaching 2500 degrees C

Abstract

To the best of our knowledge, for the first time is designed and demonstrated a single crystal Silicon Carbide (SiC)-based minimally invasive smart optical sensor suited for harsh environments and temperatures reaching 2500 degrees C. The novel sensor design is based on an agile wavelength source, instantaneous single wavelength interferometry, full optical power cycle data acquisition, free-space targeted laser beam, multiple single crystal thick SiC optical frontend chips, and multi-wavelength signal processing for unambiguous temperature measurements to form a fast and distributed smart optical sensor system. Experiments conducted using a 1550 nm eye safe band tunable laser and a 300 micron coating-free thick SiC chip demonstrate temperature sensing from room temperature to 1000 degrees C with a measured 1.3 degrees C resolution. Applications for the proposed sensor include use in fossil fuel-based power systems, aerospace/aircraft systems, satellite systems, deep space exploration systems, and drilling and oil mining industries.