Simulation and Test of Effective Area of Lobster Eye X-Ray Optical Device
Li Longhui, Gu Yan, Zhang Zhen, Xu Zhao, Zhang Chen, Lin Zhixing, Jia Zhenqing, Zhao Donghua, Jin Ge, Li Yufei, Jiang Bowen, Wu Chao, Yang Xiaoming, Song Chun, Zhou Xin, Liao Yidai, Guo Yan, Li Jingwen, Han Xiaoming, and Liu Jianqiang
Lobster eye X-ray focusing telescope is one of the important equipment for X-ray space astronomical observation in the future. This equipment will become a powerful tool to study the Earth’s space environment under various solar wind conditions. Aiming at the design and simulation of the effective area of lobster eye X-ray microporous optical devices, the relationship between structural parameters and geometric collection area is studied, and the effects of different film materials and surface roughness on X-ray reflectivity are calculated based on Fresnel formula. The performance test of effective area X-ray is completed by using X-ray beam test equipment and single-photon acquisition mode. The results show that the effective area of lobster eye optics is mainly determined by the material of the film and the roughness of the inner wall. At the same time, the effective area of Ir film can be increased from 2.15 cm 2 to 2.47 cm 2 when the energy is 1 keV.
  • May. 21, 2022
  • Acta Optica Sinica
  • Vol.42 Issue, 9 0934001 (2022)
  • DOI:10.3788/AOS202242.0934001
Polarization Imaging Detection of Individual Camouflage Based on Two-Stream Fusion Network
Wang Rongchang, Wang Feng, Ren Shuaijun, and Wang Yong
There is a high degree of color similarity between the individual camouflage target and the background, the target has a highly complex posture, and there are occlusion problems, which make individual camouflage target detection more challenging than traditional target detection. In order to solve the above problems, a depth learning algorithm based on polarization information and RGB (Red,Green,Blue) information is proposed, and the polarization image dataset CIP3K (Multicam type camouflage dataset and Woodland type camouflage dataset) is constructed. Based on Faster R-CNN (Faster Region-Convolutional Neural Network), a dual-stream feature fusion network TSF-Net is proposed, which can integrate target polarization feature information and RGB feature information. A large number of experiments are carried out on the CIP3K dataset to test the performance of the TSF-Net model and other detection models. The experimental results show that, compared with Faster R-CNN, the average detection accuracy of the TSF-Net model on the two datasets is increased by 8.2 percentages and 8.8 percentages, respectively, and is better than some mainstream object detection models.
  • May. 21, 2022
  • Acta Optica Sinica
  • Vol.42 Issue, 9 0915001 (2022)
  • DOI:10.3788/AOS202242.0915001
Theoretical and Experimental Research on 100 kHz Cavity-Dumped Thin-Disk Laser
Dong Jing, Chen Hantian, Wang Hailin, Zhu Guangzhi, Kozlov Aleksei, and Zhu Xiao
In this article, we carried out theoretical and experimental studies on the output characteristics of a cavity-dumped thin-disk laser operating at 100 kHz. Firstly, a theoretical model of the rate equation of the cavity-dumped thin-disk laser was established. The model considered the number of spontaneous emission photons newly added in the resonant cavity per unit time, and the ratio of the number of spontaneous emission photons to the total number of spontaneous emission photons was analyzed. And then we performed simulations based on some parameters. Next, we built a cavity-dumped thin-disk laser with a repetition rate of 100 kHz, and the average power of nanosecond laser pulse output was 253 W. The optical-optical efficiency was about 35.2%, the pulse width was 10.4 ns, and the single pulse energy was 2.53 mJ. The peak power exceeded 200 kW, and the optical quality M2 in the x and y directions was 9.77 and 9.27, respectively. For the dynamic stability of the cavity-dumped Q-switching, the influence of Pockels cell gate time on the output power and stability of the output pulse was further studied. In the experiment, the phenomenon of period doubling bifurcation and deterministic chaos were observed. The simulation results are consistent with the experimental results.
  • May. 21, 2022
  • Acta Optica Sinica
  • Vol.42 Issue, 9 0914002 (2022)
  • DOI:10.3788/AOS202242.0914002
Turbulence Models and Daily Variations Obtained by Bidirectional Atmospheric Coherent Length Measurements
Qiu Chenxiang, Hou Zaihong, Jing Xu, He Feng, and Zhang Silong
  • May. 21, 2022
  • Acta Optica Sinica
  • Vol.42 Issue, 9 0901002 (2022)
  • DOI:10.3788/AOS202242.0901002
Progress and Prospect of Mid-Infrared Fiber Laser Technology
Cui Yulong, Zhou Zhiyue, Huang Wei, Li Zhixian, Li Hao, Wang Meng, and Wang Zefeng
Mid-infrared laser has important application value in many fields, such as communication, remote sensing, security inspection, optoelectronic countermeasures, and so on, and has always attracted enormous attention. There are many methods for generation of mid-infrared laser, among which mid-infrared fiber lasers have the characteristics of compact structure, good beam quality, and high conversion efficiency, and so on, so they are considered as the most promising way to achieve portable, stable, efficient, and high-power mid-infrared laser emission. With the improvement of manufacturing technology of soft glass fibers, mid-infrared fiber laser technologies have achieved rapid development, and the output power level has also been greatly enhanced. However, limited by the types of rare earth ions, the fabrication process and chemical stability of soft glass fibers, the mid-infrared lasers based on soft glass fibers have technical difficulties in further improving the power and expanding the wavelength. The mid-infrared fiber gas lasers appeared in recent years provide an effective solution to these problems. The research status of mid-infrared fiber laser technologies are reviewed in detail, including the new mid-infrared fiber lasers based on gas-filled hollow-core fibers, and the development trend of mid-infrared fiber laser technologies is briefly prospected.
  • May. 21, 2022
  • Acta Optica Sinica
  • Vol.42 Issue, 9 0900001 (2022)
  • DOI:10.3788/AOS202242.0900001
LED Spectral Matching Based on Adaptive Differential Evolution Algorithm
Cheng Zhen, Si Ganshang, Li Zhengang, Ning Zhiqiang, Liu Jiaxiang, Huang Wenbiao, Si Beibei, Yang Changping, and Fang Yonghua
An adaptive differential evolution algorithm is proposed as a spectral matching algorithm to synthesize various target spectra with monochromatic light-emitting diodes (LEDs). The gaussian correction model is used to characterize the distribution of monochromatic LEDs. The standard AM1.5 solar spectrum and vegetation spectrum are simulated based on equally distributed LEDs,and the correlation coefficient and root-mean-square error are used as evaluation criteria. On this basis, the LEDs in the laboratory are used for experimental verification, and the fitting effect of the proposed algorithm is better than the simulated annealing algorithm and the genetic algorithm. The experimental results show that the proposed adaptive differential evolution algorithm, with automatic setting of parameters and good fitting effect, can be widely used in the LED spectral matching simulation tests and engineering practices.
  • May. 20, 2022
  • Acta Optica Sinica
  • Vol.42 Issue, 9 0930004 (2022)
  • DOI:10.3788/AOS202242.0930004
Dark Channel and Cross Channel Based Multi-Prior Combined Multi-Spectral Super-Resolution Algorithm
Shi Shen, Yin Zengshan, and Wang Long
In order to solve the problem that super-resolution reconstruction of multi-spectral remote sensing images is susceptible to noise and chromatic aberration, a dark channel and cross channel based multi-prior combined multi-spectral super-resolution algorithm is proposed. First, dark channel prior and cross channel prior are introduced on the basis of traditional total variational prior. Then, based on the maximum posterior probability estimation theory, a multi-spectral super-resolution reconstruction algorithm with multi-prior combination is established. The proposed algorithm can achieve image edge information restoration, image texture information restoration, noise suppression, step effect suppression and chromatic aberration suppression, which can comprehensively improve the quality of reconstructed images. Finally, the experimental verification is carried out, and the results show that the reconstruction effect of the proposed algorithm is significantly improved compared with the existing algorithms under different signal-to-noise ratios (10--40 dB) and chromatic aberrations.
  • May. 20, 2022
  • Acta Optica Sinica
  • Vol.42 Issue, 10 1010001 (2022)
  • DOI:10.3788/AOS202242.1010001
Ultra-compact post-compressor on-shot wavefront measurement for beam correction at PHELIX
J. B. Ohland, U. Eisenbarth, B. Zielbauer, Y. Zobus, D. Posor, J. Hornung, D. Reemts, and V. Bagnoud
  • May. 20, 2022
  • High Power Laser Science and Engineering
  • Vol.10 Issue, 3 03000e18 (2022)
  • DOI:10.1017/hpl.2022.9
Silicon nitride passive and active photonic integrated circuits: trends and prospects
Chao Xiang, Warren Jin, and John E. Bowers
The use of silicon nitride in integrated photonics has rapidly progressed in recent decades. Ultra-low-loss waveguides based on silicon nitride are a favorable platform for the research of nonlinear and microwave photonics and their application to a wide variety of fields, including precision metrology, communications, sensing, imaging, navigation, computation, and quantum physics. In recent years, the integration of Si and III-V materials has enabled new large-scale, advanced silicon nitride-based photonic integrated circuits with versatile functionality. In this perspective article, we review current trends and the state-of-the-art in silicon nitride-based photonic devices and circuits. We highlight the hybrid and heterogeneous integration of III-V with silicon nitride for electrically pumped soliton microcomb generation and ultra-low-noise lasers with fundamental linewidths in the tens of mHz range. We also discuss several ultimate limits and challenges of silicon nitride-based photonic device performance and provide routes and prospects for future development.
  • May. 20, 2022
  • Photonics Research
  • Vol.10 Issue, 6 06000A82 (2022)
  • DOI:10.1364/PRJ.452936
Neural network-based surrogate model for inverse design of metasurfaces
Guoqing Jing, Peipei Wang, Haisheng Wu, Jianjun Ren, Zhiqiang Xie, Junmin Liu, Huapeng Ye, Ying Li, Dianyuan Fan, and Shuqing Chen
Metasurfaces composed of spatially arranged ultrathin subwavelength elements are promising photonic devices for manipulating optical wavefronts, with potential applications in holography, metalens, and multiplexing communications. Finding microstructures that meet light modulation requirements is always a challenge in designing metasurfaces, where parameter sweep, gradient-based inverse design, and topology optimization are the most commonly used design methods in which the massive electromagnetic iterations require the design computational cost and are sometimes prohibitive. Herein, we propose a fast inverse design method that combines a physics-based neural network surrogate model (NNSM) with an optimization algorithm. The NNSM, which can generate an accurate electromagnetic response from the geometric topologies of the meta-atoms, is constructed for electromagnetic iterations, and the optimization algorithm is used to search for the on-demand meta-atoms from the phase library established by the NNSM to realize an inverse design. This method addresses two important problems in metasurface design: fast and accurate electromagnetic wave phase prediction and inverse design through a single phase-shift value. As a proof-of-concept, we designed an orbital angular momentum (de)multiplexer based on a phase-type metasurface, and 200 Gbit/s quadrature-phase shift-keying signals were successfully transmitted with a bit error rate approaching 1.67×10-6. Because the design is mainly based on an optimization algorithm, it can address the “one-to-many” inverse problem in other micro/nano devices such as integrated photonic circuits, waveguides, and nano-antennas.
  • May. 20, 2022
  • Photonics Research
  • Vol.10 Issue, 6 06001462 (2022)
  • DOI:10.1364/PRJ.450564
Optics Physics Geography All Subjects

Special lssue

Future Control Systems and Machine Learning at High Power Laser Facilities (2022)

Submission Open:1 March 2022; Submission Deadline: 31 August 2022

Editor (s): Andreas Döpp, Matthew Streeter, Scott Feister, Hyung Taek Kim, Charlotte Palmer

Ultrafast Optics: fundamentals and applications (2022)

Call for Papers

Editor (s): Shian Zhang,Shengye Jin, Olivier Faucher