Researchers from the University of Central Florida have created a new class of fiber optic sensors based on multicore optical fibers for use in harsh environment sensing. This multicore fiber sensor is simple, inexpensive, durable, sensitive, and fabricated in high volume. Additionally, this innovation allows multiple sensors to be multiplexed in series along a single fiber.
Currently available harsh environment sensor technologies are often based on electronic or SAW based wireless sensing platform technologies, with all optical fiber sensors only starting to become prevalent. The electronic and SAW based devices commonly suffer from interference and implementation issues, thus all optical fiber based sensing technologies were developed. The existing fiber sensors currently require complicated fiber geometries using suspended cores or photonic crystal fibers, making their industrial implementation impractical. Comparatively, this UCF invention improves the performance of existing multimode interference optical fiber sensors by utilizing novel multicore fiber (MCF) devices. These fiber optic sensors can be used in a variety of sensing applications including temperature, pressure, strain, acoustic vibration, mechanical vibration, or any combinations thereof.
The MCF is comprised of an arrangement of optically coupled identical cores within a silica fiber. Discrete sensors within a series are fabricated by splicing a section of multicore fiber between two single mode fibers. Via a single mode input fiber and due to multimode interference, the excitation of various modes in the MCF produces a periodic modulation of the spectral response of the device, which experiences a wavelength spectrum shift under the influence of external changes in physical parameters. Monitoring this spectrum shift provides accurate, real-time measurement of physical parameters. (e.g., temperature, pressure, strain, vibrations, etc.) The fine-tuning of the response is achievable by varying the MCF design and/or the MCF segment length. This allows sensing chains to be built by splicing various sensors in series for multipoint sensing of temperature and other metrics.
- Provides high-resolution, reproducible measurements
- Can be multiplexed in a chain
- Cost efficient
- Sensing applications
- Acoustic vibrations
- Mechanical vibrations