等离子体共振传感技术是当今实用化最强、最有可能实现单分子检测的生物医学检测技术之一。高灵敏度的等离子体共振传感技术与细如发丝的光纤载体相结合，为现代生物传感研究提供了一种可实现在体原位检测的全新方法。系统介绍了基于光纤光栅的等离子体共振生物医学传感机理与关键技术，通过能量汇聚的表面共振场实现了10-6~10-8 RIU的超高精度折射率测量，为生物医学提供了超低检出限（pM~fM量级）、特异性及原位实时检测新方法。此外，此类传感器还可提供绝对式/相对式多参量同时检测手段，能有效消除环境干扰影响，确保传感器的稳定性和可靠性。最后，回顾了近些年等离子体共振光纤光栅生物医学传感领域取得的研究进展（包括蛋白、血糖、微生物、气体等样本原位检测），并进行总结和展望。

A dual-frequency distributed Bragg reflector (DBR) fiber laser based sensor is demonstrated for low-frequency vibration measurement through the Doppler effect. The response of the proposed sensor is quite linear and is much higher than that of a conventional accelerometer. The proposed sensor can work down to 1 Hz with high sensitivity. Therefore, the proposed sensor is very efficient in low-frequency vibration measurement.

A simple fiber tip sensor for refractive index (RI) measurement based on Fabry–Perot (FP) interference modulated by Fresnel reflection is proposed and demonstrated. The sensor head consists of an etching-induced micro air gap near the tip of a single-mode fiber. The microgap and the fiber tip function as two reflectors to form a FP cavity. The external RI can be unambiguously measured by monitoring the fringe contrast of the interference pattern from the reflection spectrum. The experimental results show that the proposed sensor achieves temperature-independent RI measurement with good linear response. The proposed sensor achieves a high RI resolution of up to 3.4 \times 10 5 and has advantages of low cost and easy fabrication.

A novel all-fiber temperature-calibrated refractometer based on a compact fiber Bragg grating (FBG) single–multi–single (SMS) structure is proposed and experimentally demonstrated. The sensor head is composed of a FBG combined with a SMS structure, in which the middle multimode fiber (MMF) section is etched by a time-controlled hydrofluoric. The transmission dip of SMS is extremely sensitive to ambient refractive index (RI) variation, whereas the upstream FBG provides the necessary temperature information for RI calibration. All aforementioned functions are performed via a compact FBG-SMS structure not longer than 25 mm. The proposed sensing device provides a linear RI sensitivity over water or waterbased solutions (RI values near 1.33 at optical wavelengths for most biological and many environmental applications), and has temperature-calibration capability. Hence, the said refractometer is a good candidate for sensing in chemical and biological applications.

提出了光纤光栅啁啾化传感概念和传感机理,将光纤光栅微观分解为栅区长度范围的许多具有独立感知能力且彼此关联的有效作用子栅集,表述了有效作用子栅集与待测环境场空间梯度分布之间的对应关系,从而较好地解释了光纤光栅啁啾谱产生的内在机理。理论推导并实验验证了光栅啁啾谱各谱参量(波长、带宽和反射光强)与待测环境场(温度和应变)之间的对应关系,为利用单一光纤光栅实现多参量同时区分测量、任意非均匀空间分布场传感提供了科学有效的解决方法。