Sensitized strain sensor based on deflection amplification structure
An sensitivity-enhanced optical fiber strain sensor based on deflection amplification structure and extrinsic Fabry-Perot interferometry (EFPI)principle is proposed and demonstrated,aimed at pursuing higher precision stress detection. The key feature is to converst small axial strain variations into larger interferometric cavity length changes through the deflection amplification structure,enabling the interferometric cavity length variation exceeding 0.5 mm when the strain reaches 1500 × 10-6,making the measurement of strain magnitude more accessible and significantly enhancing the sensitivity of the sensor. Experimental validation demonstrates that the sensor possesses a measurement range of 1500 ×10-6 and a fluctuation of±0.04 ×10-6 . The research data indicates that the sensor has the advantages of long lifespan,low cost,high sensitivity,and high resolution,and is expected to be applied in the field of practical engineering structural health monitoring.