提出一种结合数字全息干涉测量原理和计算层析迭代原理的温度场三维检测方法。首先,基于光纤传导的离轴数字全息光路,通过旋转记录多角度的数字全息图。然后,对全息图进行数值重构,获得多角度上的定量相位分布,以此作为计算层析迭代的投影数据,并采用层析迭代算法重建三维折射率场分布。最后,基于折射率与温度之间的关系,反演得到三维温度场分布。基于上述方法搭建了实验系统并开展实验验证,实验测量结果与温度场预测分布基本一致,证明了该方法在对温度场三维检测的可行性。
A detecting method for 3-D temperature distribution is proposed in combination with digital holographic inter-ferometry principle and iterative tomography algorithm. The off-axis digital holographic optical path based on fiber optical conduc-tion is designed and optimized. The multi-angle digital holograms are recorded by rotation. The accurate phase data is calculatedby means of the recorded multi-angle digital holograms. The obtained multi-angle phase distributions are used as projections ofiterative tomography algorithm to reconstruct the 3-D refractive index distribution. The 3-D temperature field can be determinedby the quantitative numerical relation between the refractive index and the temperature. Based on the above method,an experi-ment system was built up and the experiment verification was carried out. The measured temperature is in good agreement withthe prediction temperature distribution. It demonstrates that digital holographic tomography is a feasible and accurate method fortemperature field detection.