Photonics Research Group of Aston University in UK has some publications on vectorial bend sensor applications.
Optical fibers can be made into interferometric sensors such as fiber-optic gyroscopes, which are used in the Boeing 767 and in some car models (for navigation purposes).
Fiber-optic sensors have been developed to measure co-located temperature and strain simultaneously with very high accuracy using fiber Bragg gratings.
[15] The measurement technique is based on polarimetric detection and high accuracy is achieved in a hostile industrial environment.
High frequency (5 MHz–1 GHz) electromagnetic fields can be detected by induced nonlinear effects in fiber with a suitable structure.
The fiber used is designed such that the Faraday and Kerr effects cause considerable phase change in the presence of the external field.
[18] Fiber Bragg grating based fiber-optic sensors significantly enhance performance, efficiency and safety in several industries.
With FBG integrated technology, sensors can provide detailed analysis and comprehensive reports on insights with very high resolution.
The modulated voltage level at the output of the PRT can then be injected into the optical fiber via the usual type of transmitter.
[20] It is well-known the propagation of light in optical fiber is confined in the core of the fiber based on the total internal reflection (TIR) principle and near-zero propagation loss within the cladding, which is very important for the optical communication but limits its sensing applications due to the non-interaction of light with surroundings.
In the above-mentioned fiber-optic structures, the enhanced evanescent fields can be efficiently excited to induce the light to expose to and interact with the surrounding medium.
However, the fibers themselves can only sense very few kinds of analytes with low-sensitivity and zero-selectivity, which greatly limits their development and applications, especially for biosensors that require both high-sensitivity and high-selectivity.