基于非相干成像的透明物体波前测量方法

Wavefront measurement for transparent object based on incoherent imaging

提出一种新的波前测量方法 ,这种方法采用了非相干成像和相移技术 ,通过相移可精确测量位相物体引起的成像光线偏折 ,然后计算波前分布。测量中 ,利用PC机显卡的双屏功能 ,其中一个显示由计算机产生的正弦灰度调制光栅图样 ,CCD记录下经过待测物体后的变形条纹图样 ,根据相移技术可以完成对透明物体波前的测量。在这一技术中 ,由于调制光栅图样是由PC产生 ,因此光栅的周期和方向可以灵活设置 ,并可以实现精确的相移。计算机模拟和实验验证了这一技术的可行性。与传统的波前干涉计量相比较 ,这种方法具有结构简单、成本低、灵活性高等优点。

A new wavefront measurement is presented,which is based on incoherent imaging and phase shift.The ray deflection of imaging caused by phase object tested could be measured accurately with the phase shift technique,and then the wavefront distribution will be calculated.Both of two displays connect to same PC display card;one displays sine intensity-modulated patterns generated by PC.When a phase object is located between the monitor and CCD camera,the intensity patterns will be distorted.Recording the distorted patterns and using phase shift technique,the measurement for wavefront of transparent phase object tested can be finished.The use of a computer display generation leads the flexible adjustment of period and direction of the patterns and accurate phase shift.Experiment measurement and computer simulation confirm its feasibility.Compared with other techniques,this technique is simpler,cheaper and more flexible.