腔损耗对基于法布里-珀罗腔强度的外置式压力传感器的影响。

School of Mathematics and Physics, China University of Geosciences, Wuhan 430074, China and State Key Laboratory of Geological Processes and Mineral Resource, China University of Geosciences, Wuhan 430074, China.

Rev Sci Instrum. 2015 Sep;86(9):095002. doi: 10.1063/1.4929681.

We present an extrinsic Fabry-Perot cavity intensity-based pressure sensor that mainly comprises a single-mode fiber end and an elastic monocrystalline silicon layer bonded to a silicon diaphragm. We investigated the influence of cavity loss on the performance indexes (PIS) of the intensity-based extrinsic Fabry-Perot cavity optical fiber pressure sensor. A buffer unit made of three incompressible oil cavities attenuated outside pressure and transformed pressure information into cavity length microchange information. Experimental results indicated that, under center quadrature-points within the linear regions of adjacent fringes, for an applied 40 kPa external pressure, cavity length was modulated by pressures of 69.9 kPa-109.9 kPa, 150.1 kPa-190 kPa, 220.1 kPa-259.9 kPa, and 279.9 kPa-319.9 kPa, output intensity ranges increased as 1 μW, 1.02 μW, 1.03 μW, and 1.05 μW, sensitivity increased as 0.01909 μW/kPa, 0.01986 μW/kPa, 0.02127 μW/kPa, and 0.02387 μW/kPa, but linearity degraded, as indicated by the standard deviation of linear fits of 0.02607, 0.02664, 0.02935, and 0.04879 due to cavity loss. Furthermore, the pressure ranges within the same quarter period decreased as 40 kPa, 37.45 kPa, 32.4 kPa, and 30.15 kPa. Consequently, the same lengths of linear regions within adjacent fringes of an approximately sinusoidal curve corresponded to different measurement ranges, linearities, and sensitivities. Initial cavity length must be chosen to optimize both signal strength and the PIS studied here in manufacturing this type sensor.

我们展示了一种基于法布里 - 珀罗腔强度的外部压力传感器，它主要由单模光纤端部和粘结在硅膜片上的弹性单晶硅层组成。我们研究了腔损耗对基于强度的外部法布里 - 珀罗腔光纤压力传感器性能指标（PIS）的影响。一个由三个不可压缩油腔组成的缓冲单元衰减外部压力，并将压力信息转化为腔长度微变化信息。实验结果表明，在相邻条纹线性区域内的中心正交点处，对于施加的40 kPa外部压力，腔长度受到69.9 kPa - 109.9 kPa、150.1 kPa - 190 kPa、220.1 kPa - 259.9 kPa和279.9 kPa - 319.9 kPa压力的调制，输出强度范围分别增加1 μW、1.02 μW、1.03 μW和1.05 μW，灵敏度分别增加0.01909 μW/kPa、0.01986 μW/kPa、0.02127 μW/kPa和0.02387 μW/kPa，但线性度下降，相邻条纹线性拟合的标准偏差分别为0.02607、0.02664、0.02935和0.04879，这是由腔损耗导致的。此外，同一四分之一周期内的压力范围分别减小为40 kPa、37.45 kPa、32.4 kPa和30.15 kPa。因此，近似正弦曲线相邻条纹内相同长度的线性区域对应不同的测量范围、线性度和灵敏度。在制造这种类型的传感器时，必须选择初始腔长度以优化信号强度和此处研究的性能指标。