随着星间通信系统的迅速发展，数据传输的精度要求不断提高。分光镜作为系统的核心元件，其光谱特性和面形精度直接影响整个系统的传输精度。本文基于薄膜干涉理论，选取Ta₂O₅与SiO₂作为高低折射率膜层材料进行膜系设计，采用电子束蒸发的方式在石英基板上制备高精度分光镜。同时根据膜层应力补偿原理建立面形修正模型，修正分光镜面形。光谱分析仪检测结果显示，分光镜在入射角度为21.5°～23.5°内，1563 nm透过率大于98%，1540 nm反射率大于99%。激光干涉仪检测结果显示，分光镜反射面形精度RMS由λ/10修正至λ/90（λ=632.8 nm），透过面形精度RMS为λ/90。

消偏振分光片是空间光学中的重要分光元件，为了实现780 nm波段激光在大分光比条件下的稳定分光输出，设计并制备了一种高分光比消偏振分光片。使用TFCalc软件仿真设计了双面消偏振分光膜系，通过离子束辅助电子束热蒸镀技术制备了消偏振分光片样品。然后，使用透射电子显微镜、分光光度计对所制备样品进行了测量表征，得到了分光片的实际薄膜结构及透射光谱，光谱结果显示该分光片的透射率接近98%，s偏振光与p偏振光的透射率偏差小于0.3%。最后，搭建测试光路对分光片进行变偏振方向、变波长及长时间稳定性等测试。实验结果表明：该分光片在目标波段内的透射率接近98%，偏振方向大范围变化时透射率偏差小于0.2%，波长在772~792 nm内变化时透射率波动小于0.12%；10 h长时结果显示，当平均时间为100 s时，分光比与透射率的Allan方差分别为1.41×10-3和4.12×10-5。所提出的消偏振分光片具有良好的消偏振性能，可直接应用于光学测试计量和量子传感探测等精密测量领域。

为了提高偏振分束器的消光比，提出了一种由混合等离子体水平狭缝波导(HSW)和氮化硅混合垂直狭缝波导(VSW)组成的双槽超紧凑偏振分束器(PBS)。同时，包层材料为二氧化硅，既能防止混合等离子体氧化，又便于与其他器件集成。采用有限元方法仿真HSW和VSW的模态特性。HSW和VSW波导在特定的宽度下TE偏振模式是满足相位匹配的，而TM偏振模式相位不匹配。因此，HSW波导中的TE模式与VSW波导发生强耦合，而TM模式直接通过HSW波导。结果表明：在1.55 μm的TE模式下，PBS的消光比(ER)为35.1 dB，插入损耗(IL)为0.34 dB，在TM模式下，PBS的ER和IL分别为40.9 dB和2.65 dB。所设计的PBS有100 nm的工作带宽，具有高ER，低IL的特点，适用于光子集成电路(PICs)。

The laser-induced damage threshold (LIDT) of plate laser beam splitter (PLBS) coatings is closely related to the subsurface absorption defects of the substrate. Herein, a two-step deposition temperature method is proposed to understand the effect of substrate subsurface impurity defects on the LIDT of PLBS coatings. Firstly, BK7 substrates are heat-treated at three different temperatures. The surface morphology and subsurface impurity defect distribution of the substrate before and after the heat treatment are compared. Then, a PLBS coating consisting of alternating HfO₂–Al₂O₃ mixture and SiO₂ layers is designed to achieve a beam-splitting ratio (transmittance to reflectance, s-polarized light) of approximately 50:50 at 1053 nm and an angle of incidence of 45°, and it is prepared under four different deposition processes. The experimental and simulation results show that the subsurface impurity defects of the substrate migrate to the surface and accumulate on the surface during the heat treatment, and become absorption defect sources or nodule defect seeds in the coating, reducing the LIDT of the coating. The higher the heat treatment temperature, the more evident the migration and accumulation of impurity defects. A lower deposition temperature (at which the coating can be fully oxidized) helps to improve the LIDT of the PLBS coating. When the deposition temperature is 140°C, the LIDT (s-polarized light, wavelength: 1064 nm, pulse width: 9 ns, incident angle: 45°) of the PLBS coating is 26.2 J/cm², which is approximately 6.7 times that of the PLBS coating deposited at 200°C. We believe that the investigation into the laser damage mechanism of PLBS coatings will help to improve the LIDT of coatings with partial or high transmittance at laser wavelengths.