中文摘要：

大口径平面光学元件的使用越来越广泛，但它的检测精度受大口径干涉仪参考面的面形误差限制。为了解决此问题，采用双平晶互检法标定干涉仪参考面的绝对面形误差，从而可以消除检测时干涉仪参考面的面形误差的影响。双平晶互检法的优点在于只需要两块平晶，并且测量过程中，不需要反复更换干涉仪的参考面，更适合大口径光学平面的绝对检测。对双平晶互检法检测光学平面的数理模型进行仿真，验证该方法的正确性，并对实验过程中的误差进行仿真分析。研究解决了目前干涉检测精度受限于参考平晶精度的瓶颈问题，同时为未来超大口径（口径大于1111）平面干涉仪参考平晶误差标定问题提供技术支撑。

英文摘要：

Large optical flat has been applied more and more extensively, but its accuracy is limited by the accuracy of the reference fiat installed in an interferometer. To solve this problem, a Two Flats Test is used to get the absolute surface deviation distribution of the reference fiat, which can eliminate the effect caused by the reference fiat. During the calibration process, the Two Flats Test simply needs two fiats--which serves as its most remarkable advantage--and it does not require changing the reference fiat of the interferometer; moreover, it fits the absolute measurement of the large optical fiat. By simulating the mathematical model of the Two Flats Test, we verify its validity and analyze the error. This research solves the bottleneck problem at present that the accuracy of the interference test is limited by the reference fiat. At the same time, it provides technological support for calibrating surface deviation distribution of the reference fiat of large fiat interferometers in the future.