[3] Hartwick T S, Hodges D T, Barker D H, et al. Far infrared imagery[J]. Applied Optics, 1976, 15(8): 1919-22.

[4] Hu B B, Zhang X C, Auston D H, et al. Free-space radiation from electro-optic crystals[J]. Applied Physics Letters, 1990, 56(6): 506-508.

[6] Wang S, Zhang X. Pulsed terahertz tomography [J]. Journal of Physics D Applied Physics, 2004, 37(4): R1.

[7] Takayanagi J, Jinno H, Ichino S, et al. High-resolution time-of-flight terahertz tomography using a femtosecond fiber laser [J]. Optics Express, 2009, 17(9): 7549-55.

[8] Ren J, Li L, Zhang D, et al. Study on intelligent recognition detection technology of debond defects for ceramic matrix composites based on terahertz time domain spectroscopy[J]. Applied Optics, 2016, 55(26): 7204-7211.

[9] Zhou Xiaodan, Li Lijuan, Zhao Duo, et al. Application of terahertz technology in nondestruct testing of ceramic matrix composite defects[J]. Infrared and Laser Engineering, 2016, 45(8): 0825001.(in Chinese)