Noninvasive mail inspection system with terahertz radiation.
Using the high penetrability of the terahertz waves and the characteristic absorption spectra in this frequency range, we have built a noninvasive mail inspection system targeting drugs and explosives. The system is composed of two stages; in the first stage, the scattering of a continuous terahertz wave is used for selecting mail that contains concealed powder; in the second stage, the absorption spectrum of the suspicious mail is measured and the material is identified using a terahertz spectrum database. We evaluated the performance and the limits of the inspection system.
Hoshina
Hiromichi
H
RIKEN, 519-1399 Aramaki-Aoba, Aoba-ku, Sendai, Miyagi, 980-0845, Japan. hoshina@riken.jp
Sasaki
Yoshiaki
Y
Hayashi
Aya
A
Otani
Chiko
C
Kawase
Kodo
K