Temperature Self-Compensated High-Temperature and Vibration Sensor Based on Step-Coated FBG Twin Reflection Spectrum

In response to the need for vibration monitoring in high-temperature harsh environments, this paper proposes a miniaturized temperature self-compensated high-temperature and vibration sensor based on step-coated metallized fiber Bragg grating (FBG) twin reflection spectrum. By nickel-plating the half-length region of a single FBG, the reflection spectrum is induced to split into twin peaks. The wavelength difference between the metallized and non-metallized regions is exploited to decouple tempe