Figure 4. The resolution performance and incident power dependence of the GRIS.

(a) A curve representing the change in voltage after injecting deionized water, a solution of 0.1% NaCl and a solution of 20% NaCl into the micro-fluid channel, respectively. The incident light power is 13.03 mW before the prism. The inset shows that the corresponding voltage difference between deionized water and a solution of 0.1% NaCl is 245 mV and the size of voice signal is ~45 mV. (b) The incident power before the prism is, from bottom to top, 0.2, 1.5, 2.8, 4.7, and 6.3 mW. The inset indicates the correspondence between the incident power before the prism and incident power before the detector. Each point corresponds to a different concentration of the sodium chloride solution: from left to right, 1, 2, 5, 10, 15, 20, and 25%. (c) Using the p-polarized light power P₀ of deionized water as calibration, a solution of 20% NaCl was injected into the GRIS to determine the changes in polarization status S₁ and P₁ for this solution under different incident powers P₀. (d) The power of s- and p-polarized light before the detector after injecting NaCl solutions with different concentrations into the microfluid channel.