Fig. 5

Numerical experiments for the grayscale resolution analysis of CCS = 40 mm: a the metrics with absorption coefficients paired as (0.0072, 0.0088 mm⁻¹), (0.0064, 0.0096 mm⁻¹), and (0.0056, 0.0104 mm⁻¹), respectively, at SNR _min = 20 dB (left) and SNR _min = 30 dB (right); b The reconstructed images of absorption coefficients paired as (0.0072, 0.0088 mm⁻¹), at SNR _min = 20 dB (left) and SNR _min = 30 dB (right)