Improving the Signal to Noise Ratio of Spectroscopy for Tongue Inspection by Optical Modulation
LI Gang1, ZHAO Jing1, LIN Ling1, WU Xiao-rong2*
1. State Key Laboratory of Precision Measurement Technology and Instruments, Tianjin University, Tianjin 300072, China 2. College of Physics & Electronic Information, Tianjin Normal University, Tianjin 300072, China
Abstract：In order to solve the problem that the collected spectrum was influenced seriously by the environment light, optical modulation was used to improve the signal to noise ratio of spectroscopy-tongue inspection for the first time. First, reference light was modulated by reticle in this system; second, the reflect spectrum of the same measured object was collected under the condition that it was influenced by green, purple, red laser and environment light respectively; thirdly, the DFT was used to demodulate the collected spectrum data; the maximum harmonic components were extracted and normalized, then the spectral curve was drawn; by comparison, the spectral curves of the same measured object under different condition were almost the same. The experiment result showed that the optical modulation can remove the influence of the environment light; and this method can provide a new way to improve the signal to noise ratio of spectroscopy for tongue inspection.
Key words：Optical modulation;Spectroscopy;Tongue inspection;Signal to noise ratio
李 刚1，赵 静1，林 凌1，吴晓荣2* . 光调制技术用于提高光谱法舌诊的测量信噪比[J]. 光谱学与光谱分析, 2012, 32(01): 192-195.
LI Gang1, ZHAO Jing1, LIN Ling1, WU Xiao-rong2* . Improving the Signal to Noise Ratio of Spectroscopy for Tongue Inspection by Optical Modulation . SPECTROSCOPY AND SPECTRAL ANALYSIS, 2012, 32(01): 192-195.
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