Silicon carbide-based remote wireless optical pressure sensor

Proposed is a silicon carbide (SiC) weak-lensingeffect-based wireless optical sensor that allows safe, repeatable, and accurate pressure measurement suitable for harsh environments. This completely passive front-end sensor design uses a remoted free-space optical beam that targets a single crystal SiC chip fitted as an optical window within a pressure capsule. With increasing differential capsule pressure, the SiC chip forms a weak convex mirror with a changing focal length. By monitoring the chip reflected light beam magnification, pressure in the capsule is determined. Using a 633-nm wavelength laser beam, the proposed sensor is experimentally tested at room temperature for 0- to 600-psi (0-41 atm) differential pressures and a remoting distance of 2.5 m