In recent years, optical phased arrays (OPAs) have attracted great interest for their potential applications in light detection and ranging (LiDAR), free-space optical communications (FSOs), holography, and so on. Photonic integrated circuits (PICs) provide solutions for further reducing the size, weight, power, and cost of OPAs. In this paper, we review the recent development of photonic integrated OPAs. We summarize the typical architecture of the integrated OPAs and their performance. We analyze the key components of OPAs and evaluate the figure of merit for OPAs. Various applications in LiDAR, FSO, imaging, biomedical sensing, and specialized beam generation are introduced.

为了实现基于双棱镜的光电跟踪平台，需要根据光束指向精确求解两棱镜转角。基于非近轴光线追迹法与二步法，利用神经网络拟合了消色差旋转双棱镜角度差值与偏转角之间的关系，并在求解方位角与消色差旋转双棱镜两组棱镜转角的时候，将其中的非线性关系与线性关系分开，利用神经网络对其中的非线性关系进行了拟合，最终得到了消色差旋转双棱镜转角与出射光束指向的数值关系。实验表明，在仅用3层神经网络共20个神经元的条件下，得到了两棱镜旋转角度反向解算值达到了 0.000 1°量级。

Lidar, a technology at the heart of autonomous driving and robotic mobility, performs 3D imaging of a complex scene by measuring the time of flight of returning light pulses. Many technological challenges, including enhancement of the observation field of view (FoV), acceleration of the imaging frame rate, improvement of the ambiguity range, reduction of fabrication cost, and component size, must be simultaneously addressed so that lidar technology reaches the performance needed to strongly impact the global market. We propose an innovative solution to address the problem of wide FoV and extended unambiguous range using an acousto-optic modulator that rapidly scans a large-area metasurface deflector. We further exploit a multiplexing illumination technique traditionally deployed in the context of telecommunication theory to extend the ambiguity range and to drastically improve the signal-to-noise ratio of the measured signal. Compacting our metasurface-scanning lidar system to chip-scale dimension would open new and exciting perspectives, eventually relevant to the autonomous vehicles and robotic industries.

Electrically connected optical metasurfaces with high efficiencies are crucial for developing spatiotemporal metadevices with ultrahigh spatial and ultrafast temporal resolutions. While efficient metal–insulator–metal (MIM) metasurfaces containing discretized meta-atoms require additional electrodes, Babinet-inspired slot-antenna-based plasmonic metasurfaces suffer from low efficiencies and limited phase coverage for copolarized optical fields. Capitalizing on the concepts of conventional MIM and slot-antenna metasurfaces, we design and experimentally demonstrate a new type of optical reflective metasurfaces consisting of mirror-coupled slot antennas (MCSAs). By tuning the dimensions of rectangular-shaped nanoapertures atop a dielectric-coated gold mirror, we achieve efficient phase modulation within a sufficiently large range of 320 deg and realize functional phase-gradient metadevices for beam steering and beam splitting in the near-infrared range. The fabricated samples show (22 % ± 2 % ) diffraction efficiency for beam steering and (17 % ± 1 % ) for beam splitting at the wavelength of 790 nm. The considered MCSA configuration, dispensing with auxiliary electrodes, offers an alternative and promising platform for electrically controlled reflective spatiotemporal metasurfaces.

基于液晶偏振光栅的快速大角度光束偏转技术在航空航天、激光通信、车载雷达、光信息处理、生物医药和**对抗等领域具有重要应用前景，并得到了极大的关注。液晶聚合物偏振光栅可以实现高效率、大角度的光束偏转，并且制备工艺简单、成本低，逐渐被应用到非机械式光束偏转系统中。本文采用两种偏振全息光路分别实现大周期和小周期的液晶聚合物偏振光栅的制备，获得的液晶聚合物偏振光栅最高衍射效率达到99.3%。级联两个液晶聚合物偏振光栅，再层叠液晶聚合物\铁电液晶\液晶聚合物波片组，实现了更大角度范围的偏转，验证了70 μs的4通道光束快速扫描。

甚多孔径光纤激光阵列是构建大功率、高光束质量、等效光学大口径的新兴技术手段之一，而基于相位精密操控实现阵列激光束的共相，乃至快速、灵活的光束偏转是当前光纤激光相控阵技术面向应用的关键。本文将光学相控扫描技术与光纤激光相干合成系统相结合，研究了甚多孔径光纤激光相控阵的光束扫描特性，通过改变准直激光阵列相邻子孔径间的相位差实现了光束扫描。对比分析了19、133、703孔径光纤激光相控阵的远场扫描光束形态分布特征，据此定义并计算了扫描极限范围。该结果为后续开展光纤激光相控阵在长程传输下精确指向控制实验研究提供了理论依据。