一种新型车载傅里叶变换红外测油仪的研制

Development of a New FTIR Car-Borne Oil Content Analyzer

水污染监测中,水中有机物含量是水质检测的重要指标。目前广泛使用的基于光栅红外分光光度方法的测油仪存在速度慢、灵敏度低、分辨率和信噪比不高等问题。应用傅里叶变换红外光谱检测技术,可以有效克服传统仪器的不足。文章研制了一种基于特伦结构的傅里叶变换红外光谱仪,有效减小仪器的体积并降低成本、提高抗环境干扰能力,使之适用于车载野外监测要求。基于干涉激光波长反馈和DSP控制的音圈电机控制系统实现直线电机运动速度误差低于5%。采用标准油样对仪器性能进行测试,实验结果表明,仪器分辨率最高为2 cm-1,信噪比达到2 000∶1。该方法与传统光栅方法相比,检测速度快,有机物光谱图性能指标显著提高,轻便易携带的特点对水质实时现场检测带来便利。

Turlun structure was introduced into the Fourier transform interference system in the present paper in order to decrease the size and cost of the whole system and to increase the ability of vibration resistance to meet the requirement of ear-borne outdoor monitoring application- The speed deviation of the voice coil motor （VCM） driving system, which is based on feedback of interference wavelength of reference laser and DSP control, is within 5 %. The standard oil sample was used to test the performance of the spectrometer. The result shows that the highest resolution of the FTIR oil detector is 2 cm^- 1, and the SNR reached 2 000 ： 1. Compared with old grating spectrometers, this.kind of instrument is faster, and the quality of spectrum was increased significantly. The portable feature of this instrument will be more convenient for the water pollution detection in field.