Development of a prototype apparatus for inspecting illicit drugs inside envelopes

The absence of practical technology to detect illicit drugs or hazardous substances hidden in sealed envelopes by nondestructive methods has made it extremely difficult to prevent them from being smuggled domestically and across international borders. We are developing a prototype apparatus that can identify these substances concealed inside sealed mail without opening it, by taking advantage of the ability of terahertz waves. We will present and discuss a current status of the development, the system configuration, the performance and the limitation of the prototype.