Wu Jin-Hui, Yang Rui-Feng, Wang Gao
National Key Laboratory for Electronic Measurement Technology, North University of China, Taiyuan 030051, China.
Guang Pu Xue Yu Guang Pu Fen Xi. 2012 Jul;32(7):1852-5.
To improve the accuracy of the transient temperature detection system, transient temperature inversion processing algorithms was proposed based on spectrum analysis of speckle pattern interferometry. The interference fringes were formed by speckle interferometry in the system, and due to transient temperature changes that cause the material strain, the speckle interference pattern changes. The interference fringes on the measured surface were obtained by the area array CCD collection before and after deformation. The corresponding spectrum density function will change with the changes in the transient temperature, and the amplitude changes of center wavelength were inverted by the speckle pattern interferometry. Through detecting and calculating the ratio of the amplitude of the center wavelength, the transient temperature can be obtained by spectrum analysis. In the analysis and calculation for the function of transient temperature and material strain, material strain and interference fringes, the amplitude and phase function of the transient temperature change and interference fringes were derived, providing the necessary conditions for detecting spectral density function temperature. The experiment used 660 nm laser diode and SI6600 type area CCD detector. By extracting the offset of the center wavelength from the spectrum distribution function, the calculation and calibration data were compared to the data obtained with the traditional method of interference temperature detection, and the result showed that the detection accuracy can achieve 0.3%. Compared to traditional direct detection of interference fringes changes, the accuracy improved nearly three times by the method.
为提高瞬态温度检测系统的精度，基于散斑图案干涉测量的频谱分析提出了瞬态温度反演处理算法。系统中通过散斑干涉测量形成干涉条纹，由于瞬态温度变化导致材料应变，散斑干涉图案发生变化。在变形前后通过面阵CCD采集测量表面上的干涉条纹。相应的频谱密度函数会随瞬态温度的变化而改变，通过散斑图案干涉测量反演中心波长的幅度变化。通过检测和计算中心波长的幅度比，可通过频谱分析获得瞬态温度。在对瞬态温度与材料应变、材料应变与干涉条纹的函数进行分析和计算时，推导了瞬态温度变化和干涉条纹的幅度与相位函数，为检测频谱密度函数温度提供了必要条件。实验采用660nm激光二极管和SI6600型面阵CCD探测器。通过从频谱分布函数中提取中心波长的偏移量，将计算和校准数据与采用传统干涉温度检测方法获得的数据进行比较，结果表明检测精度可达到0.3%。与传统直接检测干涉条纹变化相比，该方法的精度提高了近三倍。
