Study on Dynamic Spectrum and Its Frequency Domain Extracting Method
LI Gang1，LI Xiao-xia1, 2，LIN Ling1，LIU Yu-liang1，WANG Yan1，3
1. College of Precision Instrument and Opto-Electronics Engineering, Tianjin University, Tianjin 300072, China 2. School of Electrical and Automatic Engineering, Hebei University of Technology, Tianjin 300130, China 3. Liaoning Technical University, Fuxin 123000, China
Abstract：For non-invasive blood components detection using near-infrared spectrum, eliminating the influence of the individual difference is very important. In the non-invasive component measurement, the individual discrepancy refers to the difference of personal feature in measured tissues except the pulsatile component of artery blood, including hairs, horny layer, subcutaneous tissue, muscle, skeleton etc. It is declared that the individual discrepancy is different from the personal feature; it is an important factor blocking the practice of the technology. In the present article, a new method of detecting blood components is presented, which is based on the principle of photoplethysmography and Fourier transform. With this method, the influence of individual difference caused by skin and other tissues can be mostly eliminated, and the absorbance of artery blood could be obtained. The concept of the frequency domain extracting method was presented. The experiment was done and the dynamic spectrum which only evaluates the pulsatile part of the entire optical signal was obtained. The advantage of dynamic spectrum with frequency domain extracting method is analyzed. The result shows that the method can be realized and has many advantages.
[1] Lafrance Denis, Lands Larry C, Burns David H. Talanta, 2003, 60(4): 635. [2] Rosen Noah A, Charash William E, Hirsch Erwin F. Journal of Surgical Research, 2002, 106(2): 282. [3] da Costa Filho Paulo A, Poppi Ronei J. Analytica Chimica Acta 2001, 446(1-2): 39. [4] Nahm W, Gehring H. Sensors and Actuators, B: Chemical, 1995, 29(1-3): 174. [5] Niwayama M, Shiga T, Lin L, et al. Engineering in Medicine and Biology Society, 1998. Proceedings of the 20th Annual International Conference of the IEEE. 1998, Vol 4, 1849. [6] DING Hai-shu, WANG Feng, LIN Fang, SU Chang(丁海曙，王 峰, 林 芳, 苏 畅). Spectroscopy and Spectral Analysis(光谱学与光谱分析), 2001, 21(2)：155. [7] Xu Kexin, Lu Yanhui, Li Qingbo, et al. Proc. SPIE Int. Soc. Opt. Eng., 2004, 5486: 100. [8] WANG Le-xin, ZHAO Zhi-min, YAO Hong-bing, et al(王乐新 赵志敏, 姚红兵, 等). Spectroscopy and Spectral Analysis(光谱学与光谱分析), 2002, 22(6): 980. [9] TIAN Feng-hua, DING Hai-shu, WANG Guang-zhi, et al(田丰华，丁海曙, 王广志, 等). Spectroscopy and Spectral Analysis(光谱学与光谱分析), 2002, 22(2): 209. [10] Korolevich Alexander N, Meglinsky Igor V. Bioelectrochemistry and Bioenergetics, 2000, 52(2): 223. [11] Payne J P, Severinghaus J W. Pulse Oximeter. Berlin: Springer, 1986. [12] XIONG Zheng-gang, LUO Jian-qing(熊政纲，罗建清). Practical Preventive Medicine(实用预防医学), 2003, 10(2)：258.
