针对成像光学系统的波像差检测, 提出波像差梯度偏离值评价方法, 用于表征波前的成像性能.定义波像差梯度偏离值为波前成像点与成像能量中心的偏离值, 相对波像差梯度偏离值为波像差梯度偏离值与艾里斑大小的比值.相对波像差梯度偏离值与波前口径、形状、焦距均无关, 其与波像差梯度偏离值均可以用成像尺寸、成像集中度以及成像能量分布等方式进行评价.大量的波像差实际检测结果表明, 成像集中度和成像能量分布在不同的检测分辨率条件下的稳定性较好, 分辨率每相差一倍产生的差异通常小于10%.中频误差含量不同的两个球面和非球面波像差的实例比较结果表明波像差梯度偏离值可以很好地评价波像差的空间频率分布特征.根据出瞳位置的波像差梯度偏离值分布和像面位置的波像差梯度分布情况, 可以方便地指导光学加工和系统装调.该方法可以用于制定波像差指标, 进行波前质量控制.

In order to evaluate wavefront of imaging systems, the wavefront gradient deviation evaluation methods were proposed, which could directly indicate imaging performance. The wavefront gradient deviation is defined as the deviation of image spot and image energy center, and the relative wavefront gradient deviation is the ratio of wavefront gradient deviation to Airy disk radius. The wavefront gradient deviation and relative gradient deviation can be evaluated by image size, image concentration and image energy distribution. Based on dozens of practical wavefront testing results, the evaluations of image concentration and image energy distribution are usually stable enough for different test resolutions. The difference of evaluation results is usually less than 10% for every double or half resolution. An aspherical wavefront and a spherical wavefront with dramatically ripple amount were analyzed to illustrate the relationship of wavefront gradient deviation and wavefront spacial distribution. Relied on the wavefront gradient deviation distribution on exit pupil and wavefront gradient distribution on image plane, it is convenient to operate for optical manufacture and assembling. The wavefront gradient deviation evaluations can be used as the wavefront specifications for quality control.