Table 1. MSE between THz images and the ground truth.

Resonant frequency	Extinction coeff.	Proposed method
0.53 THz ( $\alpha$ -lactose)	0.17	0.03 (Fig. 4(d))
0.6 THz (PABA)	0.08	0.07 (Fig. 4(e))
0.8 THz (PABA)	0.38	0.11 (Fig. 4(f))
0.8 THz (3HBA)	0.34	0.15 (Fig. 4(g))
1.03 THz (Riboflavin)	0.52	0.15 (Fig. 4(h))