Fig. 1. Polarization spatial frequency domain imaging system. (a) Schematic; (b) physical drawing

Fig. 2. System operation flow chart

Fig. 3. Relationship between m₁₁ and reflectance of gradient diffuse reflector

Fig. 4. Schematic of decomposition experiment verification

Fig. 5. Polarization decomposition validation test results. (a) Experimental results of gradient fat emulsion solution; (b) experimental results of gradient glass sheet angle; (c) comparative experimental results of full wave plate and quarter wave plate

Fig. 6. Experimental results of polarization spatial frequency domain imaging and traditional polarized light imaging. (a) Experimental results for placing diffuse reflection plate with 0% reflectance at the bottom of fat emulsion solution; (b) experimental results for placing diffuse reflection plate with 100% reflectance at the bottom of fat emulsion solution

Fig. 7. Burn test results. (a) Burn photos of pigskin, sorted by heating time; (b) curves of depolarization coefficient and diattenuation coefficient; (c) phase delay curve

Table 1. Parameter setting in gradient fat emulsion solution experiment

Table 2. Parameter setting in gradient glass sheet angle test