Table 1 Optical parameters in the Monte Carlo simulation.

n1 = 1.3

n2 = 1.4

μa1 = 0.005 cm⁻¹

μa2 = 0.35, 0.40, …, 1.55 cm⁻¹

μs1 = 75, 125, 175 cm⁻¹

μs2 = 100 cm⁻¹

g = 0.8

g = 0.75

d1 = 0.5, 0.7 mm

d2 = 3.0, 3.1, …, 5.0 mm