2019
2019
-
Record 577 of
Title:Design of deviation detector for image stabilization system on space solar observation equipment
Author(s):He, Jiawei(1,2); Yang, Jianfeng(1); Zhang, Haiying(3)Source: Proceedings of SPIE - The International Society for Optical Engineering Volume: 10843 Issue: DOI: 10.1117/12.2506541 Published: 2019Abstract:The space solar observation equipment takes the spacecraft as the platform, and the vibration of spacecraft will have influence over the observation. Therefore, we need to develop the image stabilization system to ensure the imaging resolution. In this paper, a method for detecting the centroid deviation of solar facula is proposed. A photodiode-based deviation detector was designed based on the requirements of the image stabilization system for the Full-disc vector Magneto Graph. Compared with the traditional method of deviation detecting, it has faster response rate, lower power consumption. Backup design is added to improve the reliability of the work on orbit. According to the test results, a resolution of 5 μm is achieved within the working range. It can cooperate with the steering mirror mechanism to form the image stabilization system and serve the Full-disc vector Magneto Graph. ? 2019 SPIE ·Accession Number: 20191006603244 -
Record 578 of
Title:The image stitching algorithm based on aggregated star groups
Author(s):Qiu, Shi(1); Zhou, Dongmei(2); Du, Yun(1)Source: Signal, Image and Video Processing Volume: 13 Issue: 2 DOI: 10.1007/s11760-018-1349-y Published: March 12, 2019Abstract:The star map has the characteristics of large amount of data and wide angle of view. The star points are displayed as limited pixels on the image and easy to get disturbed by noise, so it is difficult to build a feature model to obtain the complete star map. In this paper, we have revised the OTSU algorithm and extracted the star points accurately according to the characteristics of star point pixels. We are inspired by the idea of compressed perception to break the local spatial relationship of stars, construct the aggregated star group model of relative relationship of local stars, realize the matching and construct the extended model to realize the stitching of wide angle star images. In order to meet the requirements of efficient transmission and storage in the air or on the ground, we have proposed the algorithm of star point storage and mapping. We set up a database with 600 frames of real star images from CCD camera and 600 frames of simulated star images, and the experiments show that our algorithm can compress the data and realize the star image stitching. ? 2018, Springer-Verlag London Ltd., part of Springer Nature.Accession Number: 20183605778801 -
Record 579 of
Title:Layered graphene oxide films for enhanced nonlinear optics in integrated waveguides
Author(s):Wu, Jiayang(1); Yang, Yunyi(1); Xu, Xingyuan(1); Qu, Yang(1); Jia, Linnan(1); Zhang, Yuning(1); Liang, Yao(1); Chu, Sai T.(2); Little, Brent E.(3); Morandotti, Roberto(4,5,6); Jia, Baohua(1); Moss, David(1)Source: Frontiers in Optics - Proceedings Frontiers in Optics + Laser Science APS/DLS Volume: Issue: DOI: 10.1364/FIO.2019.JTu3A.92 Published: September 8, 2019Abstract:Enhanced Kerr optical nonlinearities of waveguides integrated with layered graphene oxide (GO) films is experimentally demonstrated. Up to ~9.5-dB enhancement of four-wave mixing conversion efficiency is achieved for a waveguide with 2 layers of GO. ? OSA 2019. The Author(s).Accession Number: 20202408829911 -
Record 580 of
Title:Second-order statistical properties of a J0-correlated Schell-model beam in a turbulent atmosphere
Author(s):Yuan, Yangsheng(1,2,3); Liu, Xianlong(1); Qu, Jun(2); Yao, Min(4); Gao, Yaru(1); Cai, Yangjian(1,5,6)Source: Journal of Quantitative Spectroscopy and Radiative Transfer Volume: 224 Issue: DOI: 10.1016/j.jqsrt.2018.11.021 Published: February 2019Abstract:We derive the analytical expressions for the second-order moments of the Wigner distribution function of a J0-correlated Schell-model (JCSM) beam propagating in a turbulent atmosphere. With the help of the second-order moments, we explore the second-order statistical properties (i.e., the M2-factor, the effective radius of curvature and the Rayleigh range) of a JCSM beam propagating in a turbulent atmosphere for different turbulence parameters and beam parameters. It is found that the statistical properties of the JCSM beam are closely related to the initial beam parameters and turbulence parameters, and we can mitigate the negative effect of the turbulence by choosing suitable initial beam parameters. Our results will be useful for long distance free-space optical communications. ? 2018 Elsevier LtdAccession Number: 20184706121711 -
Record 581 of
Title:Graphene oxide for enhanced nonlinear optics in integrated waveguides
Author(s):Wu, Jiayang(1); Yang, Yunyi(1); Xu, Xingyuan(1); Qu, Yang(1); Jia, Linnan(1); Zhang, Yuning(1); Liang, Yao(1); Chu, Sai T.(2); Little, Brent E.(3); Morandotti, Roberto(4,5,6); Jia, Baohua(1); Moss, David(1)Source: Optics InfoBase Conference Papers Volume: Part F135-NOMA 2019 Issue: DOI: 10.1364/NOMA.2019.NoM3B.2 Published: 2019Abstract:We experimentally demonstrate enhanced Kerr optical nonlinearities of waveguides integrated with layered graphene oxide (GO) films. Up to ~9.5-dB enhancement of four-wave mixing conversion efficiency is achieved for a waveguide with 2 layers of GO. ? 2019 The Author(s).Accession Number: 20200107970322 -
Record 582 of
Title:Enhanced Kerr optical nonlinearity of integrated waveguides incorporating layered GO films
Author(s):Qu, Yang(1); Wu, Jiayang(1); Yang, Yunyi(1); Xu, Xingyuan(1); Jia, Linnan(1); Zhang, Yuning(1); Liang, Yao(1); Chu, Sai T.(2); Little, Brent E.(3); Morandotti, Roberto(4,5,6); Jia, Baohua(1); Moss, David(1)Source: Proceedings of SPIE - The International Society for Optical Engineering Volume: 11200 Issue: DOI: 10.1117/12.2540379 Published: 2019Abstract:We experimentally demonstrate enhanced optical Kerr nonlinearity of hybrid integrated waveguides coated with layered graphene oxide (GO) films. Owing to the high Kerr nonlinearity of GO and strong mode overlap between GO and waveguide, up to ～9.5-dB enhancement of four wave mixing (FWM) conversion efficiency is achieved. ? COPYRIGHT SPIE. Downloading of the abstract is permitted for personal use only.Accession Number: 20200808205224 -
Record 583 of
Title:Applications of Kerr micro-combs to RF photonics
Author(s):Wu, Jiayang(1); Xu, Xingyuan(1); Tan, Mengxi(1); Nguyen, Thach G.(2); Qu, Yang(1); Jia, Linnan(1); Zhang, Yuning(1); Chu, Sai T.(3); Little, Brent E.(4); Morandotti, Roberto(5,6,7); Mitchell, Arnan(2); Moss, David(1)Source: Frontiers in Optics - Proceedings Frontiers in Optics + Laser Science APS/DLS Volume: Issue: DOI: 10.1364/FIO.2019.FW6C.5 Published: September 8, 2019Abstract:We present our recent progress on RF applications based on integrated Kerr microcombs, including a broadband photonic microwave mixer, adaptive photonic RF filters with 80 taps, and photonic RF filters implemented via RF bandwidth scaling methods. ? OSA 2019. The Author(s).Accession Number: 20202408829676 -
Record 584 of
Title:Graphene oxide waveguide and micro-ring resonator polarizers
Author(s):Qu, Yang(1); Wu, Jiayang(1); Yang, Yunyi(1); Xu, Xingyuan(1); Liang, Yao(1); Chu, Sai T.(2); Little, Brent E.(3); Morandotti, Roberto(4,5,6); Jia, Baohua(1); Moss, David J.(1)Source: Proceedings of SPIE - The International Society for Optical Engineering Volume: 11200 Issue: DOI: 10.1117/12.2540370 Published: 2019Abstract:We experimentally demonstrate integrated waveguide polarizers and polarization-selective micro-ring resonators (MRRs) incorporated with layered graphene oxide (GO) films. We achieve a high polarization dependent loss (PDL) of ～53.8 dB for the GO-coated waveguide and a high polarization extinction ratio of ～8.3 dB for the GO-coated MRR. ? COPYRIGHT SPIE. Downloading of the abstract is permitted for personal use only.Accession Number: 20200808205121 -
Record 585 of
Title:Enhanced Kerr Optical Nonlinearity of Waveguides Integrated with Graphene Oxide
Author(s):Chu, Sai T.(2); Jia, Baohua(1); Jia, Linnan(1); Liang, Yao(1); Little, Brent E.(3); Morandotti, Roberto(4,5,6); Moss, David(1); Qu, Yang(1); Wu, Jiayang(1); Xu, Xingyuan(1); Yang, Yunyi(1); Zhang, Yuning(1)Source: IEEE International Conference on Group IV Photonics GFP Volume: 2019-August Issue: DOI: 10.1109/GROUP4.2019.8853911 Published: August 2019Abstract:We experimentally demonstrate enhanced optical Kerr nonlinearity of hybrid integrated waveguides coated with graphene oxide (GO). Owing to the high Kerr nonlinearity of GO and strong mode overlap between GO and waveguide, up to ～9.5-dB enhancement of four wave mixing (FWM) conversion efficiency is achieved. ? 2019 IEEE.Accession Number: 20194207560012 -
Record 586 of
Title:One-dimensional solitons in fractional Schr?dinger equation with a spatially periodical modulated nonlinearity: Nonlinear lattice
Author(s):Zeng, Liangwei(1,2); Zeng, Jianhua(1,2)Source: Optics Letters Volume: 44 Issue: 11 DOI: 10.1364/OL.44.002661 Published: June 1, 2019Abstract:The existence and stability of stable bright solitons in one-dimensional (1D) fractional media with a spatially periodical modulated Kerr nonlinearity (nonlinear lattice), supported by the recently introduced nonlinear fractional Schr?dinger equation, are demonstrated by means of the linear-stability analysis and in direct numerical simulations. Both 1D fundamental and multipole solitons (in forms of dipole and tripole ones) are found, which occupy one or three cells of the nonlinear lattice, respectively, depending on the soliton’s power. We find that the profiles of the predicted soliton families are impacted intensely by the Lévy index α, and so are their stability. The soliton families are stable if α exceeds a threshold value, below which the balance between fractional-order diffraction and the spatially modulated focusing nonlinearity will be broken. ? 2019 Optical Society of America.Accession Number: 20192307003979 -
Record 587 of
Title:Reconfigurable microwave photonic transversal filter based on an integrated optical micro-comb source
Author(s):Xu, Xingyuan(1); Wu, Jiayang(1); Tan, Mengxi(1); Nguyen, Thach G.(2); Chu, Sai T.(3); Little, Brent E.(4); Morandotti, Roberto(5); Mitchell, Arnan(2); Moss, David J.(1)Source: Proceedings of SPIE - The International Society for Optical Engineering Volume: 10921 Issue: DOI: 10.1117/12.2508152 Published: 2019Abstract:We demonstrate an 80-tap radio frequency (RF) transversal filter based on a 49GHz-spacing integrated micro-comb source. By employing a record 80 micro-comb lines, or taps, for the transversal filter, we achieve very high performance including a QRF factor more than four times higher than previous results. Our experimental results match well with theory, showing that our transversal filter is a competitive solution to implement advanced adaptive RF filters with high frequency selectivity and reconfigurability, and with potentially lower cost and footprint. This approach is promising for applications in modern radar and satellite communications systems. ? 2019 SPIE.Accession Number: 20192106949252 -
Record 588 of
Title:Infrared and visible image fusion algorithm based on saliency detection and adaptive double-channel spiking cortical model
Author(s):Zhao, C.(1); Huang, Yongdong(1,2); Qiu, Shi(3)Source: Infrared Physics and Technology Volume: 102 Issue: DOI: 10.1016/j.infrared.2019.102976 Published: November 2019Abstract:Based on the saliency detection which effectively extracts the saliency information of the image and the adaptive double-channel spiking cortical model (ADSCM) which has the advantages of global coupling, pulse synchronization, less parameters and high computational efficiency, which can well process information in dark areas, we proposed a new infrared and visible image fusion algorithm. Firstly, the infrared and visible images are decomposed into the base layer and the detail layers through the rolling guidance filter (RGF). Secondly, the base layer is fused with an improved saliency detection method, and the detail layers are fused by a directional gradient sum and an improved ADSCM. The experimental results show that the proposed method can also fully extract the target information of the infrared image while preserving the visible background information, in which the fusion effect is better than the traditional fusion algorithms. ? 2019 Elsevier B.V.Accession Number: 20193007224775