Liquid refractive index sensing independent of opacity using an optofluidic diffraction sensor.

  title={Liquid refractive index sensing independent of opacity using an optofluidic diffraction sensor.},
  author={Zhida Xu and Kevin Han and Ibrahim Khan and Xinhao Wang and G. L. Liu},
  journal={Optics letters},
  volume={39 20},
We have implemented a multifunctional optofluidic sensor that can monitor changes in the refractive index and pressure of biofluid simultaneously and can detect free-solution molecular interaction in situ. In this Letter, we demonstrate two major improvements of this sensor proven by both simulation and experiments. One improvement is the broader measurement range of refractive index by making the diffraction grating with high-index polymer. The other improvement is the separation of refractive… Expand

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