Back scattering body security inspection technology is a kind of non-intrusive body screening technology that produces the image of body surface for inspection. Through making human body exposed to X-rays with certain energy, collecting the X-rays scattered from the body surface, and carrying on statistical analysis, the image of the human body surface will be produced. In this way, all kinds of prohibited articles (such as guns, knives, explosives, drugs, etc.) carried underneath the clothes will be displayed on the image. The substances (such as metal, ceramics, etc.) with the atomic number higher than that of the human body will be darker than the normal human body in the image, and the substances (such as explosives, drugs, etc.) with the atomic number lower than that of the human body will be brighter in the image. In this way, non-intrusive inspection will be realized to inspect the objects concealed on the surface of the human body.
Since X-rays do not need to penetrate the body, suitable X-ray energy can be selected to minimize the harm to human body caused by rays: the dose per scan by back scattering equipment is only about one thousandth of the dose for a chest X-ray, only equivalent to X-ray dose absorbed in taking a 2-minute airplane.