Fig. 1. Schematic diagram of terahertz time-domain spectroscopy system

Fig. 2. Schematic diagram of multiple bonding structure and terahertz time-domain waveform

Fig. 3. Schematic diagram of flight time at different positions of upper adhesive layer

Fig. 4. [in Chinese]

Fig. 4. Flight time of difference imaging of different experimental samples

Fig. 5. Energy integral diagram of different thickness of upper rubber layer

Fig. 6. Energy integration imaging of different experimental samples

Fig. 7. Energy integration curves of different experimental samples

Fig. 8. Schematic diagram of amplitude variation of different thickness of upper adhesive layer

Fig. 9. Amplitude imaging of different experimental samples