全光纤数字散斑干涉面内变形内窥测量

Endoscopic measurement of in-plane deformation using all-fiberdigital speckle pattern interferometry

提出了一种全光纤内窥式数字散斑干涉面内变形测量方法,能够实现对深孔、空腔和被遮掩表面纯面内变形的精密测量。通过构建双光路对称照明的散斑干涉光路布局,以及设计光纤相移器,最终实现了一种稳定性高、抗干扰能力强的内窥式数字散斑干涉装置。实验装置实现了入口直径为40 mm的空腔内部面内变形直接测量,最大测试面积约为113 mm^2。实验结果表明,将实验装置安装在普通的木质办公桌上进行测量,在有人为干扰的情况下,依然可以得到比较理想的实验结果,证明了所构建的全光纤内窥式数字散斑干涉装置具有较强的抗干扰能力。

A method of in-plane deformation measurement using all-fiber endoscopic digital speckle pattern interferometry(E-DSPI)is proposed to realize the precision measurement of pure in-plane deformation of deep hole,cavity,and hidden surface.The corresponding compact and robust E-DSPI device,which has the advantages of high stability and strong anti-interference ability,is built by arranging a dual-beam symmetrical optical layout of speckle pattern interferometry and designing a fiber-based phase shifter.In the experiment,a direct measurement of the in-plane deformation inside a cavity with inlet diameter of 40 mm is realized and the maximum test area is about 113 mm^2.Ideal experimental results are obtained in the presence of artificial interference when the device is installed on an ordinary woody desk,indicating that the built all-fiber E-DSPI setup has good anti-interference ability.