Hui Zhou, Song Li, Chen Yuwei
Appl Opt. 2021 Jan 10;60(2):405-412. doi: 10.1364/AO.412481.
The dihedral angle errors (DAEs) and flatness errors of a nonideal corner cube retroreflector (CCR) determine a ground-based optical instrument's received optical power. The smaller tolerance of the dihedral angle with lower divergence is theoretically beneficial to improving the received optical power but could increase the difficulty in the fabrication and bring about a higher manufacturing cost. We propose a new method that is just dependent on the curvature radius of the front-face (CROF) of the CCR to compensate for the divergence of the output beam from the CCR caused by the DAEs. We build up a mathematical model of the received optical power based on the far-field diffraction pattern (FFDP) of the CCR and the layout of the optical instrument and investigate the effects of the DAEs and the CROF on the FFDP and the received optical power for both the coated and uncoated CCRs. Meanwhile, we present a fitting equation between the compensative CROF and the DAEs based on the principle of maximizing the received optical power. The results demonstrate that the compensative CROF has no dependence on whether the reflecting-faces of the CCR are coated or not and is inversely proportional to the absolute value of DAEs. The received optical power is promptly enhanced by utilizing the compensative CROF. Therefore, it is more feasible to improve the received optical power of the ground-based optical instrument by manipulating the CROF of the CCR rather than the DAEs.
非理想角锥棱镜(CCR)的二面角误差(DAEs)和平整度误差决定了地基光学仪器接收到的光功率。理论上,二面角公差越小且发散角越小,越有利于提高接收到的光功率,但这会增加制造难度并带来更高的制造成本。我们提出了一种仅依赖于角锥棱镜前表面曲率半径(CROF)的新方法,以补偿由二面角误差导致的角锥棱镜输出光束的发散。我们基于角锥棱镜的远场衍射图样(FFDP)和光学仪器的布局建立了接收光功率的数学模型,并研究了二面角误差和前表面曲率半径对镀膜和未镀膜角锥棱镜的远场衍射图样及接收光功率的影响。同时,我们基于使接收光功率最大化的原理,给出了补偿前表面曲率半径与二面角误差之间的拟合方程。结果表明,补偿前表面曲率半径与角锥棱镜的反射面是否镀膜无关,且与二面角误差的绝对值成反比。利用补偿前表面曲率半径可迅速提高接收光功率。因此,通过控制角锥棱镜的前表面曲率半径而非二面角误差来提高地基光学仪器接收光功率更具可行性。