Microwave body scanner are the new technology humanbody security inspection systems. These body scanner can show the human body images when passengers pass by the scanner. We use Terahertz wave, an electromagnetic wave with a wavelength between infrared and microwave. It has strong penetrability and can easily penetrate clothing.

Passive way is that human body naturely generate this kind of wave pass through clothes and detected by the system. Scanner analysis the result and show images to find the threats. Another way, active kind, is the machine to generate Terahertz wave to penetrate human body and detected by system and show body iamges.