A length-matched micro Fabry-Perot (FP) interferometer is proposed for strain measurement under irradiation environment. Theoretical simulation shows that a well length-matched FP sensor can achieve a very low drift of the cavity length and strain sensitivity in irradiation environment. In experiment, such an FP cavity is realized by laser micromachining. It shows a low cavity length drift of −0.037 µm and a strain sensitivity deviation of 0.52%, respectively, under gamma irradiation. Meanwhile, the intensity of interference fringes is also stable. As a result, such a length-matched FP cavity is a very promising candidate for strain sensing in radiative environments.

提出了一种长度匹配的微型法布里-珀罗（FP）干涉仪，用于辐照环境下的应变测量。理论仿真表明，长度匹配良好的FP传感器可以在辐照环境下实现非常低的腔长漂移和应变灵敏度。在实验中，这种FP腔是通过激光微加工实现的。在伽马辐照下，它分别显示出 -0.037 µm 的低空腔长度漂移和 0.52% 的应变灵敏度偏差。同时，干涉条纹的强度也很稳定。因此，这种长度匹配的 FP 腔是辐射环境中应变传感的非常有前途的候选者。