Zhe Sun, Tong Tian, Suk-Sim Oh, Jiang-Shan Wang, G. Cheng, Xuelong Li
{"title":"Underwater ghost imaging with pseudo-Bessel-ring modulation pattern","authors":"Zhe Sun, Tong Tian, Suk-Sim Oh, Jiang-Shan Wang, G. Cheng, Xuelong Li","doi":"10.3788/col202321.081101","DOIUrl":"https://doi.org/10.3788/col202321.081101","url":null,"abstract":"In this study, we propose an underwater ghost-imaging scheme using a modulation pattern combining offset-position pseudo-Bessel-ring (OPBR) and random binary (RB) speckle pattern illumination. We design the experiments based on modulation rules to order the OPBR speckle patterns. We retrieve ghost images by OPBR beam with different modulation speckle sizes. The obtained ghost images have a better contrast-to-noise rate compared to RB beam ghost imaging under the same conditions. We verify the results both in the experiment and simulation. In addition, we also check the image quality at different turbidities. Furthermore, we demonstrate that the OPBR speckle pattern also provides better image quality in other objects. The proposed method promises wide applications in highly scattering media","PeriodicalId":10293,"journal":{"name":"Chinese Optics Letters","volume":null,"pages":null},"PeriodicalIF":3.5,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79957840","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jingtao Dong, Tengda Zhang, Lei Yang, Yuzhong Zhang, R. Lu, Xinglong Xie
{"title":"Dark-field line confocal imaging with point confocality and extended line field for bulk defects detection","authors":"Jingtao Dong, Tengda Zhang, Lei Yang, Yuzhong Zhang, R. Lu, Xinglong Xie","doi":"10.3788/col202321.041203","DOIUrl":"https://doi.org/10.3788/col202321.041203","url":null,"abstract":"","PeriodicalId":10293,"journal":{"name":"Chinese Optics Letters","volume":null,"pages":null},"PeriodicalIF":3.5,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87797767","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"High sensitivity all-fiber bend sensor based on modal interferences in a ring core fiber","authors":"Fan Zhang, Beibei Qi, Baijin Su, Ou Xu, Yuwen Qin","doi":"10.3788/col202321.051201","DOIUrl":"https://doi.org/10.3788/col202321.051201","url":null,"abstract":"","PeriodicalId":10293,"journal":{"name":"Chinese Optics Letters","volume":null,"pages":null},"PeriodicalIF":3.5,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88119011","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Can Li, Yue Tao, Man Jiang, P. Ma, W. Liu, R. Su, Jiangming Xu, Jin-yong Leng, P. Zhou
{"title":"High-power single-frequency fiber amplifiers: progress and challenge [Invited]","authors":"Can Li, Yue Tao, Man Jiang, P. Ma, W. Liu, R. Su, Jiangming Xu, Jin-yong Leng, P. Zhou","doi":"10.3788/col202321.090002","DOIUrl":"https://doi.org/10.3788/col202321.090002","url":null,"abstract":"Unlike conventional continuous-wave lasers with wide spectra, the amplification of single-frequency lasers in optical fibers is much more difficult owing to the ultra-high power spectral density induced nonlinear stimulated Brillouin scattering effect. Nevertheless, over the past two decades much effort has been devoted to improving the power scaling and performance of high-power single-frequency fiber amplifiers. These amplifiers are mostly driven by applications, such as high precision detection and metrology, and have benefited from the long coherence length, low noise, and excellent beam quality of this type of laser source. In this paper, we review the overall development of high-power single-frequency fiber amplifiers by focusing on its progress and challenges, specifically, the strategies for circumventing the stimulated Brillouin scattering and transverse mode instability effects that, at present, are the major limiting factors of the power scaling of the single-frequency fiber amplifiers. These factors are also thoroughly discussed in terms of free-space and all-fiber coupled architecture. In addition, we also examine the noise properties of single-frequency fiber amplifiers, along with corresponding noise reducing schemes. Finally, we briefly envision the future development of high-power single-frequency fiber amplifiers.","PeriodicalId":10293,"journal":{"name":"Chinese Optics Letters","volume":null,"pages":null},"PeriodicalIF":3.5,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82628703","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Photonic and phononic interface states based on sunflower-type crystals [Invited]","authors":"Zixian Guo, Bei Yan, J. Liu","doi":"10.3788/col202321.061301","DOIUrl":"https://doi.org/10.3788/col202321.061301","url":null,"abstract":"Interface states are widely applied in waveguide devices. However, previous studies failed to achieve photonic and phononic interface states independent of each other in the same crystal structure depending on the behavior of the crystal structure, i.e","PeriodicalId":10293,"journal":{"name":"Chinese Optics Letters","volume":null,"pages":null},"PeriodicalIF":3.5,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79569843","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Single-pixel wavefront sensing via vectorial polarization modulation","authors":"æ¦ç”· æ�Ž, 毓 曹, 禹 å®�, 锋æ�° ä¹, å…¨ å™, 晓军 许","doi":"10.3788/col202321.090008","DOIUrl":"https://doi.org/10.3788/col202321.090008","url":null,"abstract":"The Shack – Hartmann wavefront sensor (SHWFS) is commonly used for its high speed and precision in adaptive optics. However, its performance is limited in low light conditions, particularly when observing faint objects in astronomical applications. Instead of a pixelated detector, we present a new approach for wavefront sensing using a single-pixel detector, which is able to code the spatial position of a light spot array into the polarization dimension and decode the polarization state in the polar coordinate. We propose validation experiments with simple and complex wavefront distortions to demonstrate our approach as a promising alternative to traditional SHWFS systems, with potential applications in a wide range of fields.","PeriodicalId":10293,"journal":{"name":"Chinese Optics Letters","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135600377","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Inverse design on terahertz multilevel diffractive lens based on 3D printing","authors":"Chenyu Shi, Yu Wang, Qiongjun Liu, Sai Chen, Weipeng Zhao, Xiaojun Wu, Jierong Cheng, Shengjiang Chang","doi":"10.3788/col202321.110006","DOIUrl":"https://doi.org/10.3788/col202321.110006","url":null,"abstract":"Terahertz (THz) lenses have numerous applications in imaging and communication systems. Currently, the common THz lenses are still based on the traditional design of a circular convex lens. In this work, we present a method for the design of a 3D-printed multilevel THz lens, taking advantage of the benefits offered by 3D printing technology, including compact size, lightweight construction, and cost-effectiveness. The approach utilizes an inverse design methodology, employing optimization methods to promise accurate performance. To reduce simulation time, we employ the finite-difference time-domain method in cylindrical coordinates for near-field computation and couple it with the Rayleigh–Sommerfeld diffraction theory to address far-field calculations. This technology holds great potential for various applications in the field of THz imaging, sensing, and communications, offering a novel approach to the design and development of functional devices operating in the THz frequency range.","PeriodicalId":10293,"journal":{"name":"Chinese Optics Letters","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135612376","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}