Renminbi selectable multiple-characteristic-point transmission authenticity-identifying method based on terahertz time-domain spectroscopy

Abstract

The invention discloses a renminbi selectable multiple-characteristic-point transmission authenticity-identifying method based on terahertz time-domain spectroscopy, comprising the following steps of: firstly transmitting total or selected characteristic points of hundred-yuan authorized renminbi by utilizing terahertz waves of discrete pulses to establish a dactylogram database of the terahertz absorption coefficients of the hundred-yuan authorized renminbi; then selecting only 3-5 transmission points to be detected on suspected renminbi to be identified by utilizing a random method according to the classified data of the dactylogram database, and enabling the terahertz waves of the discrete pulses to respectively transmit through each selected transmission point to obtain the terahertz absorption coefficient spectrums of the transmission points; and then comparing and analyzing the spectrums and the dactylogram database to judge the ascription on the authenticity of each transmission point and then judge the authenticity of the suspected renminbi to be identified. The accuracy of an identifying result is ensured through the fingerprint characteristics of the terahertz waves, thetransmission of paper sheets and the randomness of the selected transmission points to be detected; and in addition, by means of the renminbi selectable multiple-characteristic-point transmission authenticity-identifying method, overall scanning is omitted and a small quantity of characteristic points only need to be scanned, therefore the identifying time is greatly shortened.

Description

technical field [0001] The invention relates to the application field of terahertz technology, in particular to a method for authenticating RMB with optional multi-feature point transmission based on terahertz time-domain spectroscopy technology. Background technique [0002] Terahertz (Terahertz, THz) radiation usually refers to between microwave and infrared light, with a frequency between 0.1THz and 10THz (1THz=10 12 Hz) electromagnetic waves, the electromagnetic radiation in this band has many unique properties. Terahertz wave technology mainly has the following characteristics: (1) Terahertz time-domain spectroscopy technology adopts coherent measurement technology, which can not only obtain the amplitude information of the instantaneous electric field of the terahertz wave, but also obtain the phase information. (2) The terahertz band has rich fingerprint characteristics, corresponding to the rotational or vibrational energy levels of most molecules. Many organic mole...

AI Technical Summary

Problems solved by technology

However, if the azimuth of a few characteristic transmission points is fixed, once it is used by counterfeiters, it will not be conducive to the identification of suspected RMB

Therefore, if the selection method of the orientation of several characteristic transmission points is changed from fixed selection to random selection, according to the fingerprint characteristics of terahertz waves and the randomness of feature point selection, if the counterfeit currency passes the terahertz wave transmission identification smoothly, the The terahertz absorption coefficient spectrum of each point on the counterfeit coin must be exactly the same as the fingerprint spectrum of the corresponding point on the real coin, and the counterfeiter can only make counterfeit coins if the technology, process, parameters and equipment must be exactly the same as the National Mint Only under these conditions can it be possible to create counterfeit coins that look like real ones, and in most cases, counterfeiters cannot meet such technical conditions

At present, there is no use of discrete pulse terahertz waves and only scanning a few randomly selected feature points with different fingerprints on suspected RMB to be identified, and using the terahertz transmission and absorption coefficient fingerprints of each corresponding feature point of genuine RMB to identify suspected RMB. Reports identified as true or false

Images