中国激光, 2009, 36 (2): 403, 网络出版: 2009-02-23  

大光学深度波长调制吸收光谱的研究

Study of Wavelength Modulation Absorption Spectroscopy under Large Optic Depth
作者单位
中国科学院上海光学精密机械研究所, 上海 201800
摘要
由于在高光学深度下,比尔-朗伯特(Beer-Lambert)定律的线性近似不再成立,波长调制光谱(WMS)中常用的偶次谐波探测失效。比较研究了适用于高光学深度的对数光谱方法和比值方法,理论研究了这两种方法的测量分辨率以及信号幅度随光学深度变化的规律,研制了一套波长调制光谱光纤甲烷传感器。得到了对数方法中光源功率调制的傅里叶系数表达式; 研究了制约对数光谱方法和比值方法分辨率的因素。研究表明,对数光谱方法的测量分辨率高于比值方法2~3个数量级。
Abstract
Linear approximation of Beer-Lambert law is no longer accepted under high optic depth, so that the popular 2nd harmonic detection in wavelength modulation spectroscopy(WMS) becomes invalid. Logarithmic spectroscopy in WMS is compared with the second-to-first harmonic ratio method. The relationship between harmonic signal and optical depth as well the resolution of both is studied theoretically. WMS optical fiber methane sensor at 1650 nm are described. The Foureier coefficients of amplitude modulation of laser in logarithmic spectroscopy are achieved, and the factors affecting the resolution of both methods are studied. The results show that signal-to-noise ratio(SNR) with the logarithmic method is 2~3 order larger than that of ratio method.

王允韬, 蔡海文, 耿建新, 方祖捷. 大光学深度波长调制吸收光谱的研究[J]. 中国激光, 2009, 36(2): 403. Wang Yuntao, Cai Haiwen, Geng Jianxin, Fang Zujie. Study of Wavelength Modulation Absorption Spectroscopy under Large Optic Depth[J]. Chinese Journal of Lasers, 2009, 36(2): 403.

关于本站 Cookie 的使用提示

中国光学期刊网使用基于 cookie 的技术来更好地为您提供各项服务,点击此处了解我们的隐私策略。 如您需继续使用本网站,请您授权我们使用本地 cookie 来保存部分信息。
全站搜索
您最值得信赖的光电行业旗舰网络服务平台!