Research On The Recognition And Verification Device Of Renminbi Based On Ultraviolet Fluorescent Signal

Renminbi (RMB) anti-counterfeit is an important issue of the national economy development, the development of anti-counterfeit technology is significant to the progress of opening-up and reform policy of China and to maintain normal economy order and currency stabilization. Since RMB was published in our country, the number of the case of RMB counterfeit has been growing up, and false currency has been made just like true. In this situation, quality control department should make full use of its own technology advantage to generalize anti-counterfeit technology, combine cracking down with keeping away, and further study the corresponding strategy, especially to false currency made in high-tech.This paper, aimed at the recognition and verification of the fourth and fifth version RMB, employs detecting the reflected light of ultraviolet fluorescent mark as a basic method to research and explore, by means of the microcontroller-based intelligent judgment. A kind of low-cost, universal recognition and verification device of paper currency is designed and carried out.The work that has been finished in this research is as follows:Selection of the wavelength that produced by an ultraviolet light source. In the experiment, it is found that when ultraviolet light wavelength is between 360nm and 410nm, the longer the wavelength is, the smaller the signal-to-noise is and the lower the price of LED is. The length of LED used in this paper is 400nm.The research in color character of the reflected light from ultraviolet fluorescence marks of true and false currency. Different color of reflected light can be observed in experiments, when the same kind of ultraviolet light respectively irradiates the fluorescent mark of true and false currency. And therefore the color sensor can be used to detect different signal.Design and implement of detecting circuit based on microcontroller system. A/D convert function and real time signal processing function of microcontroller are utilized.Design and achievement of the intelligent recognition and alarming program. According to the equipment shape and paper currency movement when checked, recognition process is divided into three steps. The judgment standard in each step is established, and then the information is synthesized to recognize the paper currency.Finally the reliability of recognition system is verified by experiments.