偏振剪切干涉法测量光学元件的热弹性形变
Measurement of Thermo-Elastic Deformation of an Optic using a Polarization Based Shearing Interferometer
摘要：
本文提出了一种剪切干涉仪，它利用偏振控制来剪切波前和调制干涉图样。剪切是由双折射晶体中的空间走离产生的。通过调节双折射晶体的取向，波前梯度的分量可以被独立地测量，以允许确定全波前矢量梯度以及波前的重构。此外，用于剪切的晶体的单片性质允许设置干涉仪而不需要任何部件的精确对准。提出了一种结合零差检测的算法，该算法分析调制干涉图以确定波前梯度的分量，由此重构波前。利用该系统对高斯泵浦光加热引起的反射镜热变形进行了精确的观测，灵敏度优于λ/160。我们证明了这种灵敏度是尺度不变的，并提出了一种方法来解释干涉仪的非均匀空间频率响应。
英文摘要：
A shearing interferometer is presented which uses polarization control to shear the wavefront and to modulate the interference pattern. The shear is generated by spatial walk-off in a birefringent crystal. By adjusting the orientation of the birefringent crystal, the components of the wavefront gradient can be independently measured to allow determination of the full wavefront vector gradient as well as reconstruction of the wavefront. Further, the monolithic nature of the crystal used for shearing allows the interferometer to be setup without need for precise alignment of any components. An algorithm incorporating homodyne detection is presented which analyzes the modulated interferograms to determine the components of the wavefront gradient, from which the wavefront is reconstructed. The thermal deformation of a mirror subject to heating from absorption of a Gaussian pump beam was accurately observed with a sensitivity better than λ/160. We show that this sensitivity is scale invariant, and present a method to account for the non-uniform spatial frequency response of the interferometer.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
