High-efficiency monolayer metallic metasurface for modulation of orbital angular momentum
Peijun Liu, Yanan Fu, Xi Xie, Changjun Min, Yuquan Zhang, and Xiaocong Yuan
  • Jul. 13, 2022
  • Chinese Optics Letters
  • Vol. 20 Issue 12 123601 (2022)
  • DOI:10.3788/COL202220.123601
Symmetry detection of rotating patterns based on rotational Doppler effect of light
Fang Han, Weijie Wang, Tong Liu, Yuan Ren, Zhengliang Liu, and Song Qiu
  • Aug. 10, 2022
  • Chinese Optics Letters
  • Vol. 20 Issue 12 122601 (2022)
  • DOI:10.3788/COL202220.122601
Crystal growth and spectral properties of (Yb0.15Lu0.85xY0.85-0.85x)3Al5O12 single crystals
Ruifeng Tian, Mingyan Pan, Lu Zhang, and Hongji Qi
  • Aug. 09, 2022
  • Chinese Optics Letters
  • Vol. 20 Issue 12 121601 (2022)
  • DOI:10.3788/COL202220.121601
Generating large topological charge Laguerre–Gaussian beam based on 4K phase-only spatial light modulator
Ruijian Li, Yuan Ren, Tong Liu, Chen Wang, Zhengliang Liu, Jie Zhao, Rusheng Sun, and Ziyang Wang
The resolution of the spatial light modulator (SLM) screen and the encoding algorithm of the computer-generated hologram are the primary limiting factors in the generation of large topological charge vortex beams. This paper attempts to solve these problems by improving both the hardware and the algorithm. Theoretically, to overcome the limitations of beam waist radius, the amplitude profile function of large topological charge Laguerre–Gaussian (LG) beam is properly improved. Then, an experimental system employing a 4K phase-only SLM is set up, and the LG beams with topological charge up to 1200 are successfully generated. Furthermore, we discuss the effect of different beam waist radii on the generation of LG beams. Additionally, the function of the LG beam is further improved to generate an LG beam with a topological charge as high as 1400. Our results set a new benchmark for generating large topological charge vortex beams, which can be widely used in precise measurement, sensing, and communication.
  • Aug. 11, 2022
  • Chinese Optics Letters
  • Vol. 20 Issue 12 120501 (2022)
  • DOI:10.3788/COL202220.120501
End-to-end optimization of a diffractive optical element and aberration correction for integral imaging
Xiangyu Pei, Xunbo Yu, Xin Gao, Xinhui Xie, Yuedi Wang, Xinzhu Sang, and Binbin Yan
In the integral imaging light field display, the introduction of a diffractive optical element (DOE) can solve the problem of limited depth of field of the traditional lens. However, the strong aberration of the DOE significantly reduces the final display quality. Thus, herein, an end-to-end joint optimization method for optimizing DOE and aberration correction is proposed. The DOE model is established using thickness as the variable, and a deep learning network is built to preprocess the composite image loaded on the display panel. The simulation results show that the peak signal to noise ratio value of the optimized image increases by 8 dB, which confirms that the end-to-end joint optimization method can effectively reduce the aberration problem.
  • Aug. 09, 2022
  • Chinese Optics Letters
  • Vol. 20 Issue 12 121101 (2022)
  • DOI:10.3788/COL202220.121101
Fast dual-beam alignment method for stimulated emission depletion microscopy using aggregation-induced emission dye resin
Miao Zhao, Fengming Liu, Yang Yu, Xinjun Guo, Hao Ruan, and Jing Wen
A stimulated emission depletion is capable of breaking the diffraction limit by exciting fluorescent molecules with a solid Gaussian beam and quenching the excited molecules with another donut beam through stimulated emission. The coincidence degree of these two beams in three dimensions will significantly influence the spatial resolution of the microscope. However, the conventional alignment approach based on raster scanning of gold nanoparticles by the two laser beams separately suffers from a mismatch between fluorescence and scattering modes. To circumvent the above problems, we demonstrate a fast alignment design by scanning the second beam over the fabricated sample, which is made of aggregation-induced emission (AIE) dye resin. The relative positions of solid and donut laser beams can be represented by the fluorescent AIE from the labeled spots in the dye resin. This design achieves ultra-high resolutions of 22 nm in the x/y relative displacement and 27 nm in the z relative displacement for fast spatial matching of the two laser beams. This study has potential applications in scenarios that require the spatial matching of multiple laser beams, and the field of views of different objectives, for example, in a microscope with high precision.
  • Jun. 29, 2022
  • Chinese Optics Letters
  • Vol. 20 Issue 11 113601 (2022)
  • DOI:10.3788/COL202220.113601