Xue Yulong, Zhang Qihao, Ren Yangming, Lei Yufang, Sun Xiaochen, Zhang Lingxuan
Appl Opt. 2022 Aug 20;61(24):7158-7162. doi: 10.1364/AO.463542.
We report a two-dimensional Si photonic optical phased array (OPA) optimized for a large optical aperture with a minimal number of antennas while maintaining single-lobe far field. The OPA chip has an optical aperture of ∼200µ by 150 µm comprising a 9×9 antenna array. The two-dimensional spacings between these antennas are much larger than the wavelength and are highly non-uniform optimized by the genetic deep learning algorithm. The phase of each antenna is independently tunable by a thermo-optical phase shifter. The experimental results validate the design and exhibit a 0.39×0.41 beamwidth within the 3 dB steering range of 14×11 limited by the numerical aperture of the far-field camera system. The method can be easily extended to a larger aperture for narrower beamwidth and wider steering range.
我们报道了一种二维硅光子光学相控阵（OPA），该相控阵针对大光学孔径进行了优化，天线数量最少，同时保持单瓣远场。OPA芯片的光学孔径约为200µ×150 µm，包含一个9×9天线阵列。这些天线之间的二维间距远大于波长，并通过遗传深度学习算法进行了高度非均匀优化。每个天线的相位可通过热光移相器独立调谐。实验结果验证了该设计，并在远场相机系统数值孔径限制的14×11的3 dB转向范围内呈现出0.39×0.41的波束宽度。该方法可轻松扩展到更大孔径，以实现更窄的波束宽度和更宽的转向范围。
