1. What is the millimeter wave?

The millimeter wave is the electromagnetic wave with a wavelength of 1 to 10 millimeters. It is in the common range of microwave wavelength and far infrared, so it shares the spectral characteristics of both. The millimeter wave plays an important role in communication, radar, control and guidance, remote sensing technology, radio astronomy, clinical medicine and spectroscopy, and more. Due to the frequency of the millimeter wave of the atmospheric window, it is possible to carry out high-capacity satellite-terrestrial communication or terrestrial communication. With the narrow wave and its low level of the side lobe of the millimeter wave antenna, you can follow the radar with a low extension angle and obtain radar images. When the long-range missile or spacecraft returns to the atmosphere, the millimeter wave, which is capable of penetrating plasma, is applied to perform communication and guidance. The high resolution millimeter wave radiometer is suitable for remote sensing of meteorological parameters. With the millimeter and sub-millimeter wave radio telescope, the space radiation spectrum can be detected and the composition of the interstellar substance inferred.

2. The Technical Principle of Millimeter Wave Imaging Active millimeter wave holographic imaging technology generates images with the ability to penetrate normal clothing. The system emits the millimeter wave in a frequency range frequency to the human body. The wave penetrates clothing and is reflected by touching the body surface or objects hidden under clothing. The system extracts useful information by receiving the reflected wave and generates the millimeter wave holographic image, by which it can be determined whether there are suspicious objects hidden on the body surface.

3. Why is the millimeter wave used for safety inspection?

The millimeter wave lies between the infrared and the microwave in the frequency spectrum. Compared to visible and infrared light, the millimeter wave can not only penetrate most non-metallic objects, but also features microwave resolution. In addition, the millimeter wave is non-ionizing radiation, whose electromagnetic radiation is only one thousandth of the telephone radiation, so it has no harm to the human body and is safer than the microwave. The millimeter wave image does not see clothing, but coins, buttons, pens, keys, among other objects, such as pistols, bombs, drugs, and other contraband materials, are clearly visible on the human body.

4. The NUCTECH Millimeter Wave Human Body Inspection System is an active millimeter wave imaging device characterized by fast scanning, complete and reliable copying, privacy protection and automatic identification of contraband materials .

 

Radioactivity Detection Gamma rays or neutrons emitted by radioactive substances strike the detectors and react with the detection means (such as the plastic scintillator, Nal (TI), or He-3, etc.). The energy produced is converted into Impulse electrical signals and signals are transmitted and recorded in the data acquisition and processing system.

For a simple alarm system, the system determines whether there are excess radioactive substances on the inspected objects according to the change in the number of pulses per unit time. For the radionuclide identification system, various electrical impulse signals are recorded on the multichannel analyzer and a ray energy spectroscopy is formed with the pulse amplitude as the horizontal axis and the number of impulses as the vertical axis.

As the energies of the rays emitted by different radionuclides vary, it is feasible to analyze the energy spectroscopy using the advanced radionuclide identification algorithm and distinguish the types of radionuclides that cause the alarm, in order to provide the client with more support for their decisions. NUCTECH offers a series of radioactive substance monitoring and nuclear radiation measurement systems, which help customers to control radiation sources, automatically monitor the level of radiation in the environment, and combat illegal transportation of nuclear material. .

At the same time, a foundation of advanced systems integration technology and the above-affected products, Integrated Environmental Radiation Monitoring Systems, developed by NUCTECH, can provide customers with more comprehensive security inspection solutions.

 

Backscatter inspection technology is a type of non-intrusive scanning technology of the human body with images of the body surface. The system emits certain energy X-rays to the body, collects the reflected and analyzed rays to obtain the image of the body surface.

Banned items such as pistols, knives, explosives and drugs and more, hidden under clothing are shown in the image. Non-intrusive inspection of objects transported above the human body such as substances, metals, ceramics and more can be performed with atomic numbers higher than those of the human body. These images appear darker than the human body, while substances such as explosives and drugs, with lower atomic numbers, appear lighter.

Since X-rays do not need to penetrate the human body, you can choose an adequate X-ray energy to minimize damage to the body. The typical single scan dose is one thousandth of the chest x-ray, and is only equal to the 2 minute absorbed dose on the plane.

The technical principle of the practice of ion mobility spectrometry (IMS according to the terms in English) consists of the inspection cameras in the bypass tube, through the semipermeable membrane that has the function of selective permeability, after they are heated and vaporized at the entrance.

 

After ionization by the ionizing source, the different molecules form groups of molecular ions, which drift towards the detectors at different speeds under the influence of the electrical field of the shunt tube, and ultimately form current pulses in the detectors, which that allows to present the ion mobility spectroscopy, with the mobility time as its transverse axis, and the current intensity as its vertical axis.

Because the speed of mobility is based on mass, size, and electrical charge, different substances are distinguished in spectroscopy by peaks at different positions. With the development of technology, in addition to the classic ion mobility spectrometry, high electric field asymmetric ion mobility spectrometry (FAIMS) and other new technologies have been developed.

IMS-based inspection has become the most practical method for trace detection in the detection of narcotic drugs, explosives, chemical warfare agents and industrial toxic gas, etc., because IMS systems can operate under atmospheric pressure and count with high detection sensitivity, fast analysis, small size, light weight and very low power consumption.