大口径光学平晶在天文望远镜、激光核聚变装置、空间相机等大型光学系统中具有广泛应用，在其检测过程中会受到震动、湍流、温度漂移等时变因素的影响。现有口径大于600mm激光干涉仪基本采用时间移相方式，不能有效克服环境干扰。本项目针对天文镜面的动态测试需求，拟开展异位点光源阵列同步相移干涉方法研究，由点光源阵列的垂轴位置差异在干涉图中引入相移，并通过空间分光成像透镜阵列同步采集四幅相移干涉图，由此解算待测光学面形。研究内容包括：（1）建立点光源阵列与干涉腔的函数关系，揭示点光源异位空间移相规律，发展等步长相移控制方法；（2）建立基于透镜阵列组件的干涉场空间分光与精确共轭模型，揭示时空移相机理；（3）建立空间移相干涉图位相重构模型，研究干涉图的一致性标定方法，研究点光源阵列非线性辐射与干涉波前谐波之间的函数关系。本项目研究及成果将为我国自主发展12m天文望远镜、南极天文望远镜等重大科学工程增强技术手段。

Large aperture optical flat is widely used in large optical systems such as astronomical telescopes, laser fusion devices, space cameras. The test result will be affected by temporal error sources including environment vibration, atmospheric turbulence, and temperature drift. Most laser interferometers with the aperture over 600mm at present are based on temporal phase shifting interferometry, which cannot avoid environmental disturbance effectively. To meet the requirement of the dynamic test for astronomical mirrors, the simultaneous phase shifting interferometry will be studied based on displaced point source array, which induces phase shifts into four individual interferograms by the lateral displacement of the point source array. In order to separate the four phase-shifting interferograms captured in one shot, an imaging lens array is employed to translate and conjugate the fringe pattern on to the CCD target. And the surface figure of the test mirror will be retrieved at last. The research includes (1) To study the relationship between the point source array orientation and the cavity interval to reveal the spatial phase shifting discipline. (2) To develop fringe pattern duplication and conjugate relation model by means of the lens array to propose the spatial phase shifting algorithm. (3) Based on the phase reconstruction model, the consistency calibration method will be studied and the relationship between the nonlinear radiation of the point source array and the interference wavefront harmonics will be analyzed. The result of research can provide the technical approach for the independent development of 12m telescope, Antarctic astronomical telescope and other major scientific projects.