| Raman scattering effect which was found by Indian scientist Raman in1928attracts more and more attentions as it can be directly used to determine the molecular’s stucture and composition of the material. At the same time it does not touch and make any modification to the sample.In addition to Raman, it also generates fluorescence when the material is been irradiated by excitation light. Usually, the intensity of fluorescence can reach106～108times of Raman scattering light whose intensity is generally very weak. Therefore it is very important to effectively restrain fluorescence interference for the development of Raman spectroscopy analysis technique.This paper adopts Shifted-Excitation Raman Difference Spectroscopy which is commonly used to filter fluorescence. According to the key technologies of SERDS namely laser source and restoration algorithms, this paper develops a dual wavelength LD driver, gives a detail introduction of its composition and working principle and certifies its stability and reliability through experiment. Besides, it also infers the deconvolution algorithm combined with the spectral character and on this basis states a more stable and reliable algorithm which has verified its availability in the MATLAB considering on noise and other factors which exist in the process of actual testing.The performance tests of the drive power system for semiconductor laser diode are done. The experimental results demonstrate that the current stability is superior to0.05% and the range of temperature is less than0.01℃. The system can guarantee the stability of excitation wavelength effectively and also meet the SERDS’s requirements. Finally, perform the Raman spectroscopy detection test on a sample to get the difference spectrum with the help of epistasis software, digital optical switch, fibre-optical probe, sample cell, QE65pro spectrograph which are comprised of platform and gain good effect through algorithm processing. |
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