Figure 2
From: Optical monitoring of the plant growth status using polarimetry

(a) Probability density plotted on the Poincaré sphere surface corresponding to polarization states of light after passing through the reference lettuce seedling leaves after 10 days of planting and (b) that of Stokes parameters obtained from the reference seedlings. (c) Box chart of |s3| and (d) means of GEV parameters as a function of treatment days for seedlings with different NaCl concentrations.