山东省海洋原位传感器工程技术协同创新中心

Fabry-Perot liquid refractive index sensor based on polymethyl methacrylate

  • 发表刊物: Eighth Symposium on Novel Photoelectronic Detection Technology and Applications
  • 关键字: Fabry-Perot interferometer, Refractive index sensor, polymethyl methacrylate
  • 是否译文:
  • 发表时间: 2022-03-01
摘要: Liquid refractive index (RI) is one of the important optical parameters closely related to density, concentration, and
temperature. The measurement of liquid RI is widely used in chemistry, medicine, physics, and biology research. A FabryPerot interferometer-based liquid RI sensor by using PMMA polymer material is proposed and demonstrated
experimentally. The influence of cavity length and reflectivity on the sensor sensitivity is theoretically investigated. A long
cavity length gives rise to a small free space range. In the experiment, high reflectivity of F-P cavity is made by evaporating
metal film (aluminum film). An open F-P interferometer is realized by punching a hole in the PMMA plate, which is
convenient for liquid exchange and in situ measurement. Experimental results show that the FSR the F-P cavity is about 5
nm with a fringe contrast of 3 dB. The designed sensor is compact, low-cost, easy fabrication and flexible replacement.