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。

A polarization-insensitive mode-order converting power splitter using a pixelated region is presented and investigated in this paper. As TE₀ and TM₀ modes are injected into the input port, they are converted into TE₁ and TM₁ modes, which evenly come out from the two output ports. The finite-difference time-domain method and direct-binary-search optimization algorithm are utilized to optimize structural parameters of the pixelated region to attain small insertion loss, low crosstalk, wide bandwidth, excellent power uniformity, polarization-insensitive property, and compact size. Experimental results reveal that the insertion loss, crosstalk, and power uniformity of the fabricated device at 1550 nm are 0.57, -19.67, and 0.094 dB in the case of TE polarization, while in the TM polarization, the relevant insertion loss, crosstalk, and power uniformity are 0.57, -19.40, and 0.11 dB. Within a wavelength range from 1520 to 1600 nm, for the fabricated device working at TE polarization, the insertion loss, crosstalk, and power uniformity are lower than 1.39, -17.64, and 0.14 dB. In the case of TM polarization, we achieved an insertion loss, crosstalk, and power uniformity less than 1.23, -17.62, and 0.14 dB.

Mode splitters that directly separate modes without changing their orders are highly promising to improve the flexibility of the mode-division multiplexing systems. In this paper, we design a high-performance mode splitter on the silicon-on-insulator platform with a compact footprint of 14 µm× 2.5 µm using an inverse design method based on shape optimization. The fabrication of this mode splitter requires only a single lithography step and exhibits good fabrication tolerances. The experimental results show that the proposed device exhibits state-of-the-art insertion loss (<0.9 dB) and cross talk (<-16 dB) over a broad bandwidth (1500–1600 nm). Furthermore, the shape optimization method used is implemented to design a dual-mode (de)multiplexer, and the experimental results fulfill the design objective, demonstrating the excellent generality of the design method in this paper.

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。

针对太赫兹波段固态大功率应用需求，基于氮化镓功率放大器单片集成电路（Monolithic Microwave Integrated Circuit，MMIC），采用功率合成技术实现了太赫兹波段瓦级功率输出。通过太赫兹波段微带/波导转换结构和键合金丝补偿技术，结合E面T型结二路合成功率分配/合成器，将两片MMIC封装成最大输出功率为160 mW的功率单元模块。在此基础上，采用八路E面合成器设计了频率覆盖180～238 GHz的十六路功率合成放大器。在漏极电压为+10 V时，带内输出功率大于300 mW，189 GHz输出功率达到了1.03 W。