Prohibited article detection method and device

Abstract

The invention discloses a method and device for detecting contraband items. The method includes: placing the measured object in a terahertz optical path, measuring the terahertz time-domain waveform data of the measured object; Fourier transform to obtain the terahertz frequency domain waveform data of the measured object; calculate the absorption spectrum data of the measured object according to the terahertz frequency domain waveform data of the measured object and the reference terahertz frequency domain waveform data; Compare the absorption spectrum data of the substance with the characteristic peak data of the standard products of various prohibited items stored in the database in advance, and judge whether the measured substance is one of the prohibited items; the characteristic peak data of the standard products of the prohibited items are specifically obtained from the The data of the peak selected among the peaks of the absorption spectrum data of the standard substance. In the technical solution of the present invention, according to the comparison result of the absorption spectrum data of the tested substance and the characteristic peak data of the standard products of various contraband items, it can be more accurately judged whether the tested substance is a prohibited substance.

Description

technical field [0001] The invention relates to the field of spectroscopy, in particular to a method and device for detecting contraband items. Background technique [0002] At present, the detection of prohibited items has been widely used in airports, customs, stations, ports, nuclear power plants, government agencies, postal inspection centers, courts, embassies and other places to detect prohibited items carried by people or in luggage , thereby ensuring safety. [0003] An existing detection method for prohibited items is: use X-rays to irradiate the measured object, and display the shape and outline of the measured object according to the principle of X-ray transmission, and display the measured objects with different densities in different colors , for example, organic substances are displayed in orange, inorganic substances are displayed in blue, and mixtures are displayed in green. According to the shape, outline and color displayed by the contraband detection dev...

AI Technical Summary

Problems solved by technology

However, for chemical prohibited items (such as explosives, drugs), the shape of the prohibited item is usually difficult to predict; in fact, both prohibited items and daily necessities can contain only low atomic number components and only high atomic number components , or contain both low atomic number components and high atomic number components; the gray scale displayed by the prohibited item is usually the same or similar to the gray scale displayed by daily necessities; it is difficult for the inspectors to identify chemical substances according to the detection method of the prohibited item class of prohibited items

[0005] In summary, using the existing detection methods for prohibited items, the accuracy of judging whether the tested object is a prohibited item is relatively low; therefore, it is necessary to provide a method and device for detecting prohibited items with higher accuracy

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