Optical fiber Fabry-Perot interferometer coupled to a 3-D integrated waveguide for 3-D position sensing

Area of Science:

• Optoelectronics
• Fiber Optic Sensors
• Interferometry

Background:

• Extrinsic Fabry-Perot interferometers (EFPIs) are widely used for precise displacement sensing.
• Conventional EFPIs are limited to one-dimensional measurements.
• Advanced sensing capabilities are needed for multi-dimensional physical quantity measurement.

Purpose of the Study:

• To propose and demonstrate a novel extrinsic Fabry-Perot interferometer (EFPI) for three-dimensional (3-D) displacement sensing.
• To develop a compact hybrid sensor integrating optical fiber and optical waveguides.
• To achieve sub-micron resolution in 3-D positioning measurements.

Main Methods:

• Fabrication of a hybrid EFPI device using a lead-in optical fiber and a 3-D integrated optical waveguide array.
• Simultaneous measurement of reflected and transmitted light from the EFPI.
• Application of machine learning-based analysis for 3-D positioning data interpretation.

Main Results:

• Successful demonstration of a 3-D extrinsic Fabry-Perot interferometer (EFPI) sensor.
• Achieved sub-micron resolution for 3-D positioning.
• Validated the use of optical waveguides as external reflectors in EFPIs.

Conclusions:

• The proposed hybrid EFPI sensor enables accurate 3-D displacement measurements.
• This approach overcomes the 1-D limitation of conventional EFPIs.
• The integration of optical waveguides and machine learning offers a new pathway for compact, multi-dimensional sensing.