基于干涉腔外调制的同步共轭差分绝对检验方法研究

大口径光学元件是高分辨率对地观测、天文光学、激光核聚变等国家重点发展领域的基础部件。高精度绝对检验是其加工精度的基本保障。该技术目前尚未成熟，是限制我国相应领域发展的瓶颈。国内外现有方法均建立在干涉腔多次调整及移相干涉测量基础上，干涉腔调整复杂且不稳定，难以应用于大口径元件。如何避免调整干涉腔并在腔内非稳状态下实现绝对检验是亟待解决的科学问题。对此，本项目提出开展同步共轭差分绝对检验研究。首先，研究干涉腔外调制方法，产生相干波面之间横向错位的同时，避免了调整干涉腔；其次，研究干涉光路中的空间复用方法，实现相干波面多重错位干涉图同步获取及分离；再次，研究偏振复用方法，实现多组干涉信号同步移相，在非稳态情况下获取波面数据；最后，与共轭差分波面复原技术结合，针对大口径元件进行绝对检验实验研究。本项目研究将为我国自主建立大口径光学平面基准及溯源校准体系奠定基础，支撑相应重点领域的发展。

Lager aperture optical components are the basic elements of several national key areas, like high resolution observation, astronomical optics, laser fusion, and so on. Absolute test is the guarantee of corresponding fabrication. However, in China it is not yet mature, and now is the obstruction to the development of such topics mentioned above. All the traditional methods are based on the phase-shifting technique and complex operations to the interemetric cavity, which are not suitable to the lager aperture optical components. So it is a scientific problem to realize absolute test without any change to the cavity which is instable. Accordingly, research on simultaneous conjugate differential absolute test is proposed. First, external modulation is proposed to introduce lateral separation between the two coherent wavefronts, which avoids adjustments to the cavity. Secondly, spatial multiplexing is proposed to obtain and separate the interferograms of the several overlapping interferencing waves. Thirdly, polarization multiplexing technique is introduced to realize simultaneous phase-shifting to the interferograms. Finally, together with traditional conjugate differential absolute test reconstruction technique, experimental research on the absolute test of large aperture optics is proposed. The proposal will contribute to the establishment of our national large aperture optics standard and calibration system, while supporting the development of corresponding areas.