Fig. 4.

Phantoms with coupled ${\mu }_s^{\prime }$ and γ variation. (a) Photograph, (b) annotation of ${\mu }_s^{\prime }$ and D_f values. Panels (c)–(e) show reflectance images at λ = 658 nm and f _x = [0; 0.2; 0.5] mm⁻¹ , while panels (f )–(h) show absolute values of reflectance versus D_f at each level of ${\mu }_s^{\prime }$ for each spatial frequency. The dashed lines in (h) correspond to areas within (e) and highlight the non-uniqueness of the reflectance intensity with respect to combinations of ${\mu }_s^{\prime }$ and γ. Panels (i),(j), and (k) show recovered γ(658 nm), scatter slope B, and ${\mu }_s^{\prime }$(658 nm) maps. Below are corresponding plots of recovered optical property values versus D_f in (l), (m), and (n), where the blue error bars represent recovered mean values ± one standard deviation, the black circles represent the Mie theory predicted γ(658 nm) and ${\mu }_s^{\prime }$(658 nm) values, and the black dotted line represents a regression of scatter slope B versus D_f (r = 0.983). Scale bar is 2 mm.