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Optical design of wide-field and broadband light field camera for high-precision optical surface defect detection
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作者 Chengchen Zhou Yukun Wang +7 位作者 Yue Ding Dacheng Wang Jiucheng Nie Jialong Li Zhixi Li Zheng Zhou Shuangshuang Zhang Xiaokun Wang 《Astronomical Techniques and Instruments》 2026年第1期64-74,共11页
To address the challenges of high-precision optical surface defect detection,we propose a novel design for a wide-field and broadband light field camera in this work.The proposed system can achieve a 50°field of ... To address the challenges of high-precision optical surface defect detection,we propose a novel design for a wide-field and broadband light field camera in this work.The proposed system can achieve a 50°field of view and operates at both visible and near-infrared wavelengths.Using the principles of light field imaging,the proposed design enables 3D reconstruction of optical surfaces,thus enabling vertical surface height measurements with enhanced accuracy.Using Zemax-based simulations,we evaluate the system’s modulation transfer function,its optical aberrations,and its tolerance to shape variations through Zernike coefficient adjustments.The results demonstrate that this camera can achieve the required spatial resolution while also maintaining high imaging quality and thus offers a promising solution for advanced optical surface defect inspection. 展开更多
关键词 Optical design Defect detection wide-field camera Broadband light field camera
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Electrical Detection of Shale Gas Layers Based on Wide-Field Electromagnetic Method
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作者 Man Li-Xin Tan Zhang-Kun +3 位作者 Jia Jian-Chao Gu Zhi-Wen Yu Chang-Heng Yin Xue-Bo 《Applied Geophysics》 2025年第3期878-890,898,共14页
The drilling gas production situation indicates a certain correlation between the shale gas reservoir in the Sichuan Basin and the high and low changes in formation resistivity.These variations are observed in the fir... The drilling gas production situation indicates a certain correlation between the shale gas reservoir in the Sichuan Basin and the high and low changes in formation resistivity.These variations are observed in the first member of the Longmaxi Formation to the Wufeng Formation at the bottom of the Longmaxi Formation.Given this correlation and based on the logging electrical data,this study employs the wide-field electromagnetic method(WFEM)to experimentally detect the electrical characteristics of the deep shale gas target layer in the Yibin area of southern Sichuan.The study also tests the regularity and effectiveness of the electrical parameters for evaluating favorable areas of shale gas reservoirs.In terms of specific operation,the structural pattern of the study area is implemented based on the wide-field electromagnetic results and geological data for comprehensive analysis,which identifies the main hidden faults and their influence range on low resistance.The detailed spatial distribution of the upper Ordovician Wufeng Formation and the lower Silurian Longmaxi Formation in the target layer with a buried depth of 2000-5000m is described.This layer exhibits the characteristics of a continuous and stable distribution of organic shale.After verifying the subsequent electrical logging data,the electrical logging curve is found to be essentially consistent with the shape and trend of the wide-field resistivity curve.This consistency demonstrates the effectiveness of WFEM in detecting shale gas layers. 展开更多
关键词 wide-field electromagnetic method feasibility study Shale gas exploration Recognition accuracy structural pattern
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Application of a wide-field electromagnetic method to shale gas exploration in South China 被引量:8
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作者 杨学立 李博 +1 位作者 彭传圣 杨洋 《Applied Geophysics》 SCIE CSCD 2017年第3期441-448,462,共9页
In an effort to reduce the shale gas exploration risks and costs, we applied the wide-field electromagnetic method (WFEM), because of its strong anti-interference capability, high resolution, ability to conduct expl... In an effort to reduce the shale gas exploration risks and costs, we applied the wide-field electromagnetic method (WFEM), because of its strong anti-interference capability, high resolution, ability to conduct exploration at large depths, and high efficiency, to the Bayan Syncline in the South Huayuan block, Hunan Province. We collected rock samples and analyzed their resistivity and induced polarization (IP) and built A series of two-dimensional models for geological conditions to investigate the applicability of WFEM to different geological structures. We also analyzed the correlation between TOC of shale and the resistivity and IP ratio to determine the threshold for identifying target formations. We used WFEM to identify the underground structures and determine the distribution, depth, and thickness of the target strata. Resistivity, IP, and total organic carbon were used to evaluate the shale gas prospects and select favorable areas (sweet spots) for exploration and development. Subsequently, drilling in these areas proved the applicability of WFEM in shale gas exploration. 展开更多
关键词 wide-field electromagnetic method shale gas RESISTIVITY induced polarization total organic carbon
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Extracting useful high-frequency information from wide-field electromagnetic data using time-domain signal reconstruction 被引量:1
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作者 LING Fan YANG Yang +6 位作者 LI Gang ZHOU Chang-yu HUANG Min WANG Xin ZHANG Heng ZHU Yu-zhen SUN Huai-feng 《Journal of Central South University》 SCIE EI CAS CSCD 2022年第11期3767-3778,共12页
The wide-field electromagnetic method is widely used in hydrocarbon exploration,mineral deposit detection,and geological disaster prediction.However,apparent resistivity and normalized field amplitude exceeding 2048 H... The wide-field electromagnetic method is widely used in hydrocarbon exploration,mineral deposit detection,and geological disaster prediction.However,apparent resistivity and normalized field amplitude exceeding 2048 Hz often exhibit upward warping in data,making geophysical inversion and interpretation challenging.The cumulative error of the crystal oscillator in signal transmission and acquisition contributes to an upturned apparent resistivity curve.To address this,a high-frequency information extraction method is proposed based on time-domain signal reconstruction,which helps to record a complete current data sequence;moreover,it helps estimate the crystal oscillator error for the transmitted signal.Considering the recorded error,a received signal was corrected using a set of reconstruction algorithms.After processing,the high-frequency component of the wide-field electromagnetic data was not upturned,while accurate high-frequency information was extracted from the signal.Therefore,the proposed method helped effectively extract high-frequency components of all wide-field electromagnetic data. 展开更多
关键词 wide-field electromagnetic method crystal oscillator error time series signal resampling signal reconstruction
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Non-contact wide-field viewing system-assisted scleral buckling surgery for retinal detachment in silicone oilfilled eyes 被引量:1
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作者 Su-Lan Wu Yi-Qi Chen +7 位作者 Li-Jun Shen Jian-Bo Mao Li Lin Ji-Wei Tao Huan Chen Shi-An Zhang Jia-Feng Yu Chen-Xi Wang 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第4期761-766,共6页
AIM:To evaluate scleral buckling(SB)surgery using a noncontact wide-field viewing system and 23-gauge intraocular illumination for the treatment of rhegmatogenous retinal detachment in silicone oil(SO)-filled eyes.MET... AIM:To evaluate scleral buckling(SB)surgery using a noncontact wide-field viewing system and 23-gauge intraocular illumination for the treatment of rhegmatogenous retinal detachment in silicone oil(SO)-filled eyes.METHODS:Totally 9 patients(9 eyes)with retinal detachment in SO-filled eyes were retrospectively analyzed.All patients underwent non-contact wide-field viewing system-assisted buckling surgery with 23-gauge intraocular illumination.SO was removed at an appropriate time based on recovery.The patients were followed up for at least 3mo after SO removal.Retinal reattachment,complications,visual acuity and intraocular pressure(IOP)before and after surgery were observed.RESULTS:Patients were followed up for a mean of 8.22mo(3-22mo)after SO removal.All patients had retinal reattachment.At the final follow-up,visual acuity showed improvement for 8 patients,and no change for 1 patient.The IOP was high in 3 patients before surgery,but it stabilized after treatment;it was not affected in the other patients.None of the patients had infections,hemorrhage,anterior ischemia,or any other complication.CONCLUSION:This new non-contact wide-field viewing system-assisted SB surgery with 23-gauge intraocular illumination is effective and safe for retinal detachment in SO-filled eyes. 展开更多
关键词 non-contact wide-field viewing system scleral buckling silicone oil-filled retinal detachment
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Combined Application of Wide-Field Electromagnetic Method and Flow Field Fitting Method for High-Resolution Exploration: A Case Study of the Anjialing No. 1 Coal Mine 被引量:22
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作者 Jishan He 《Engineering》 2018年第5期667-675,共9页
The Anjialing No. 1 Coal Mine in Shanxi Province, China, contains a complicated old goaf and an unknown water distribution that hold high potential for serious water hazards. Due to poor detection resolution, previous... The Anjialing No. 1 Coal Mine in Shanxi Province, China, contains a complicated old goaf and an unknown water distribution that hold high potential for serious water hazards. Due to poor detection resolution, previous attempts have failed to determine the scope of the old goal and the water distribution in the mine by separate use of various exploration methods such as seismic method, direct current resistivity, audio magnetotellurics, controlled-source audio-frequency magnetotellurics, and transient electromag-netics. To solve this difficult problem, a combination of the wide-field electromagnetic method and the flow field fitting method with three-dimensional resistivity data inversion was applied to determine the precise scope of the goal and the locations where water is present, and to identify the hydraulic con- nection between the water layers so as to provide reliable technical support for safe coal production. Reasonable results were achieved, with all these goals being met. As a result, a mining area of nearly 4 km^2 has been released for operation. 展开更多
关键词 wide-field electromagnetic method Flow field fitting method GoalWater abundance High-resolution exploration
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Wide-Field Vibrational Phase Contrast Imaging Based on Coherent Anti-Stokes Raman Scattering Holography 被引量:1
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作者 吕永钢 纪子衡 +2 位作者 董大山 施可彬 龚旗煌 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第7期86-89,共4页
We propose and implement a wide-field vibrational phase contrast detection to obtain imaging of imaginary components of third-order nonlinear susceptibility in a coherent anti-Stokes Raman scattering (CARS) microsco... We propose and implement a wide-field vibrational phase contrast detection to obtain imaging of imaginary components of third-order nonlinear susceptibility in a coherent anti-Stokes Raman scattering (CARS) microscope with full suppression of the non-resonant background. This technique is based on the unique ability of recovering the phase of the generated CARS signal based on holographic recording. By capturing the phase distributions of the generated CARS field from the sample and from the environment under resonant illumination, we demonstrate the retrieval of imaginary components in the CARS microscope and achieve background free coherent Raman imaging. 展开更多
关键词 wide-field Vibrational Phase Contrast Imaging Based on Coherent Anti-Stokes Raman Scattering Holography
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Application of wide-field electromagnetic method for favorable target optimization in the Heishan granite geothermal area of Yunnan Province 被引量:1
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作者 Jie Li Honghu Zeng +2 位作者 Xiaoyong Lu Chao Xu Jingrui Chen 《Natural Gas Industry B》 2024年第1期74-82,共9页
The Heishan geothermal area is positioned above the sole Yunnane-Tibet high-temperature geothermal belt,where huge geothermal energy resources are available.Utilizing the characteristics of large exploration depth,ext... The Heishan geothermal area is positioned above the sole Yunnane-Tibet high-temperature geothermal belt,where huge geothermal energy resources are available.Utilizing the characteristics of large exploration depth,extensive coverage,and high precision of the wide-field elec-tromagnetic method,four survey lines were deployed,totaling 29.8 km,to enable a comprehensive analysis of the granite structure and fault distribution.The results indicate that the rocks within the area can be vertically divided into a granite basement and a fractured layer.Moreover,three different zones of resistivity were identified:the granite basement zone has a resistivity range of 2500-20000 U m,whereas the compressional shear zone and the secondary fault zone have a resistivity range of 750-2500 U m,and the extensional fault zone and the main fault zone have resistivity values below 750 U m.The Heishan-Hejian fault and the fault zone formed during its right-lateral strike-slip process,as well as the controlled area of the Qianmaihe fault,are all favorable targets.Of these,the Qianmahe fault possesses a larger-scale heat-conducting and water-controlling structure.In addition,in the secondary fault-controlled area extending to the west,the zone between F2’and F4 exhibits renewed tectonic activity,suggesting a greater potential for geothermal resources. 展开更多
关键词 Heishan geothermal area wide-field electromagnetic method Medium-deep geothermal Heat-conducting structure DESERT
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基于水平磁总场的地空广域电磁法响应提取方法
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作者 周聪 覃展梓 +3 位作者 李杰 尹文斌 汤井田 丁文蔷 《中国有色金属学报》 北大核心 2026年第2期456-470,共15页
地空广域电磁法采用移动平台接收以提高效率,但姿态误差严重影响测量精度。本文提出了一种基于水平磁总场的地空广域电磁法响应提取方法,论证了水平磁总场的旋转不变性,讨论了水平磁总场广域视电阻率的计算方案。通过模拟和实测算例分... 地空广域电磁法采用移动平台接收以提高效率,但姿态误差严重影响测量精度。本文提出了一种基于水平磁总场的地空广域电磁法响应提取方法,论证了水平磁总场的旋转不变性,讨论了水平磁总场广域视电阻率的计算方案。通过模拟和实测算例分析了磁场分量的响应特性与观测范围,论证了水平磁总场观测和响应计算的可行性。结果表明,水平磁场的总场强度在远区和过渡区内高于垂直磁场,可获得更好的观测信噪比;当存在测量角度偏差造成姿态误差时,水平磁场分量H_(x)和H_(y)视电阻率曲线会发生一定的畸变;而水平磁总场观测方案可以有效地避免姿态误差所带来的影响,具有观测范围大、磁场强度高、旋转不变性等特征,是当前技术条件下航空/半航空广域电磁法较为合理的测量方案。 展开更多
关键词 电磁勘探 广域电磁法 航空电磁法 视电阻率 姿态校正
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Patterned line-illumination mesoscopy with a moving slit for enhancing background suppression in cortex-wide mouse brain imaging
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作者 Chaowei Zhuang Yi Yang Hao Xie 《Chinese Physics B》 2026年第2期679-684,共6页
Wide-field mesoscopy provides the capabilities of cortex-wide field of view(FOV),cellular resolution and high frame rate for neuronal imaging in the mouse brain.However,inherent background fluorescence degrades the im... Wide-field mesoscopy provides the capabilities of cortex-wide field of view(FOV),cellular resolution and high frame rate for neuronal imaging in the mouse brain.However,inherent background fluorescence degrades the image quality and hinders neuronal signal extraction.To address this problem,we first introduce a cortex-wide,high-resolution lineillumination mesoscope with a moving slit designed for in vivo mouse brain imaging.This system achieves a 6.6×6.6 mm FOV,microscale cellular resolution,a high frame rate of 10 Hz,as well as the background rejection ability.Furthermore,we integrated patterned illumination into the system to enhance the background suppression.Experimental results show that the proposed system successfully captures neurodynamics in the living mouse brain.Compared with conventional wide-field mesoscopes,the cortex-wide patterned line-illumination mesoscope(PLIM)achieves a threefold increase in the signal-to-background ratio(SBR).With patterned illumination integrated,the SBR enhancement further reaches four-anda-half-fold. 展开更多
关键词 wide-field fluorescence imaging optical sectioning patterned illumination
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Chip-scale metalens microscope for wide-field and depth-of-field imaging 被引量:9
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作者 Xin Ye Xiao Qian +7 位作者 Yuxin Chen Rui Yuan Xingjian Xiao Chen Chen Wei Hu Chunyu Huang Shining Zhu Tao Li 《Advanced Photonics》 SCIE EI CAS CSCD 2022年第4期68-75,共8页
Microscopy is very important in research and industry,yet traditional optical microscopy suffers from the limited field-of-view(FOV)and depth-of-field(DOF)in high-resolution imaging.We demonstrate a simultaneous large... Microscopy is very important in research and industry,yet traditional optical microscopy suffers from the limited field-of-view(FOV)and depth-of-field(DOF)in high-resolution imaging.We demonstrate a simultaneous large FOV and DOF microscope imaging technology based on a chip-scale metalens device that is implemented by a SiNxmetalens array with a co-and cross-polarization multiplexed dual-phase design and dispersive spectrum zoom effect.A 4-mm×4-mm FOV is obtained with a resolution of 1.74μm and DOF of200μm within a wavelength range of 450 to 510 nm,which definitely exceeds the performance of traditional microscopes with the same resolution.Moreover,it is realized in a miniaturized compact prototype,showing an overall advantage for portable and convenient microscope technology. 展开更多
关键词 metalens MICROSCOPE wide-field imaging
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Metalens-integrated compact imaging devices for wide-field microscopy 被引量:21
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作者 Beibei Xu Hanmeng Li +6 位作者 Shenglun Gao Xia Hu Cheng Yang Chen Chen Feng Yan Shining Zhu Tao Li 《Advanced Photonics》 EI CSCD 2020年第6期1-8,共8页
Metasurfaces have demonstrated unprecedented capabilities in manipulating light with ultrathin and flat architectures.Although great progress has been made in the metasurface designs and function demonstrations,most m... Metasurfaces have demonstrated unprecedented capabilities in manipulating light with ultrathin and flat architectures.Although great progress has been made in the metasurface designs and function demonstrations,most metalenses still only work as a substitution of conventional lenses in optical settings,whose integration advantage is rarely manifested.We propose a highly integrated imaging device with silicon metalenses directly mounted on a complementary metal oxide semiconductor image sensor,whose working distance is in hundreds of micrometers.The imaging performances including resolution,signal-to-noise ratio,and field of view(FOV)are investigated.Moreover,we develop a metalens array with polarization-multiplexed dual-phase design for a wide-field microscopic imaging.This approach remarkably expands the FOV without reducing the resolution,which promises a non-limited space-bandwidth product imaging for wide-field microscopy.As a result,we demonstrate a centimeter-scale prototype for microscopic imaging,showing uniqueness of meta-design for compact integration. 展开更多
关键词 metalens compact imaging device polarization multiplexing wide-field microscopy.
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陕南安康地区页岩气广域电磁法探测及有利区分析
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作者 孙健 罗卫锋 +6 位作者 张家政 周志 周惠 康海霞 王立波 杨南坤 罗林涛 《物探与化探》 2026年第1期53-64,共12页
陕南安康地区具备页岩气成藏的地质条件和资源潜力,但是经历多期构造作用,页岩储层存在一定程度的破坏,如何寻找局部页岩气富集有利区带成为安康地区页岩气探测亟须解决的关键问题。为此,本文以安康地区下寒武统牛蹄塘组、鲁家坪组作为... 陕南安康地区具备页岩气成藏的地质条件和资源潜力,但是经历多期构造作用,页岩储层存在一定程度的破坏,如何寻找局部页岩气富集有利区带成为安康地区页岩气探测亟须解决的关键问题。为此,本文以安康地区下寒武统牛蹄塘组、鲁家坪组作为重点调查层系,开展了广域电磁法探测研究,采用综合信息建模与反演成像技术,查明了该研究区的地层电性结构、断裂构造及目标层底界面展布特征,结合页岩有机地球化学特征确定了页岩气勘探的有利区及远景区。研究成果对安康地区进一步开展页岩气勘探工作具有重要的指导意义,给国内其他类似页岩气的地球物理勘探提供参考和借鉴。 展开更多
关键词 页岩气 广域电磁法 牛蹄塘组 鲁家坪组 安康
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Wide-field ophthalmic space-division multiplexing optical coherence tomography 被引量:4
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作者 JASON JERWICK YONGYANG HUANG +3 位作者 ZHAO DONG ADRIENNE SLAUDADES ALEXANDER J.BRUCKER CHAO ZHOU 《Photonics Research》 SCIE EI CSCD 2020年第4期539-547,共9页
High-speed ophthalmic optical coherence tomography(OCT)systems are of interest because they allow rapid,motion-free,and wide-field retinal imaging.Space-division multiplexing optical coherence tomography(SDMOCT)is a h... High-speed ophthalmic optical coherence tomography(OCT)systems are of interest because they allow rapid,motion-free,and wide-field retinal imaging.Space-division multiplexing optical coherence tomography(SDMOCT)is a high-speed imaging technology that takes advantage of the long coherence length of micro electro mechanical vertical cavity surface emitting laser sources to multiplex multiple images along a single imaging depth.We demonstrate wide-field retinal OCT imaging,acquired at an effective A-scan rate of 800,000 A-scans/s with volumetric images covering up to 12.5 mm×7.4 mm on the retina and captured in less than 1 s.A clinical feasibility study was conducted to compare the ophthalmic SDM-OCT with commercial OCT systems,illustrating the high-speed capability of SDM-OCT in a clinical setting. 展开更多
关键词 wide-field ophthalmic space-division multiplexing optical coherence tomography
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Design of a wide-field target detection and tracking system using the segmented planar imaging detector for electro-optical reconnaissance 被引量:9
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作者 于清华 武冬梅 +1 位作者 陈福春 孙胜利 《Chinese Optics Letters》 SCIE EI CAS CSCD 2018年第7期34-39,共6页
Detecting and tracking multiple targets simultaneously for space-based surveillance requires multiple cameras,which leads to a large system volume and weight. To address this problem, we propose a wide-field detection... Detecting and tracking multiple targets simultaneously for space-based surveillance requires multiple cameras,which leads to a large system volume and weight. To address this problem, we propose a wide-field detection and tracking system using the segmented planar imaging detector for electro-optical reconnaissance. This study realizes two operating modes by changing the working paired lenslets and corresponding waveguide arrays: a detection mode and a tracking mode. A model system was simulated and evaluated using the peak signal-to-noise ratio method. The simulation results indicate that the detection and tracking system can realize wide-field detection and narrow-field, multi-target, high-resolution tracking without moving parts. 展开更多
关键词 FOV Design of a wide-field target detection and tracking system using the segmented planar imaging detector for electro-optical reconnaissance
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广域电磁法技术进展与多领域应用综述
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作者 何继善 张大伟 +4 位作者 蒋奇云 张钱江 尹文斌 李杰 童小畅 《中国有色金属学报》 北大核心 2026年第2期409-429,共21页
广域电磁法作为我国地球物理勘探领域具有原创性的技术突破,基于伪随机信号编码与严格的数学解理论,重构了电磁勘探方法体系,有效克服了传统电磁法在探测深度、分辨率及环境适应性等方面的技术瓶颈。本文系统总结了该技术体系的创新性进... 广域电磁法作为我国地球物理勘探领域具有原创性的技术突破,基于伪随机信号编码与严格的数学解理论,重构了电磁勘探方法体系,有效克服了传统电磁法在探测深度、分辨率及环境适应性等方面的技术瓶颈。本文系统总结了该技术体系的创新性进展:在理论方法层面,提出强干扰背景下的广域电磁数据处理新方法,构建了深部探测与浅层勘查相衔接、航空观测与地面勘探相协同的立体探测技术框架;在装备研制领域,突破了大功率发射系统优化、抗干扰信号采集及多平台集成适配等关键技术,成功实现从陆地固定式装备到深海拖曳系统、航空探测平台的全链条国产化技术升级;在工程应用方面,重点展示了该方法在固体矿产勘探、油气资源评价、地热田勘查、煤田水害预警、页岩气压裂监测及地质灾害识别等领域的创新应用成果,验证了其多场景应用的适应性与可靠性;还前瞻性探讨了人工智能大模型解释算法开发及地质灾害动态监测网络构建等发展方向,为服务国家“深地探测”“海洋强国”战略及地质灾害防控体系建设提供理论依据与技术支撑。 展开更多
关键词 广域电磁法 协同探测 伪随机信号 高精度
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地空广域电磁法观测响应精度的关键影响因素分析
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作者 原源 谭歌 +1 位作者 汤井田 周翔 《中国有色金属学报》 北大核心 2026年第2期471-484,共14页
地空广域电磁法(GAWFEM)是广域电磁法(WFEM)的新分支,其观测方案设计亟须完善。本文开展了地空广域电磁法观测响应精度的影响因素研究。首先,介绍了地空广域电磁法的基本原理,说明了所采用的三维数值模拟算法;然后,通过与典型一维层状... 地空广域电磁法(GAWFEM)是广域电磁法(WFEM)的新分支,其观测方案设计亟须完善。本文开展了地空广域电磁法观测响应精度的影响因素研究。首先,介绍了地空广域电磁法的基本原理,说明了所采用的三维数值模拟算法;然后,通过与典型一维层状模型的半解析解对比,验证了算法的可靠性和地-空观测响应的有效性。在此基础上,设计典型应用场景和地电模型,分析了不同测量参数对空中观测磁场值的影响。结果表明:地空广域电磁法的观测响应精度受多种因素影响,其中最大的影响因素为观测分量,水平磁场分量强度在适宜观测的频段均强于垂直磁场分量;影响水平磁场分量观测精度的因素依次为激励方位、飞行方向、飞行速度和飞行高度。 展开更多
关键词 电磁勘探 广域电磁法 航空电磁 三维正演 数值模拟
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电偶源频域电磁测深法阻抗全区视电阻率的模拟与应用
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作者 杨亮 黄美俊 +5 位作者 周聪 朱吉星 林鹏 麻昌英 刘寄仁 丁文蔷 《中国有色金属学报》 北大核心 2026年第2期485-499,共15页
常规E-E_(x)广域电磁法视电阻率的计算依赖电流强度、发收距等场源参数,当电流因复杂地电条件发生畸变时或发收位置等参数记录有误时将导致计算结果偏倚。本文阐述了电偶源频域电磁测深法阻抗全区视电阻率、卡尼亚视电阻率和E_(x)广域... 常规E-E_(x)广域电磁法视电阻率的计算依赖电流强度、发收距等场源参数,当电流因复杂地电条件发生畸变时或发收位置等参数记录有误时将导致计算结果偏倚。本文阐述了电偶源频域电磁测深法阻抗全区视电阻率、卡尼亚视电阻率和E_(x)广域视电阻率的计算方法;通过三维正演模拟,设计典型复杂地电模型,对比了不同视电阻率的响应结果;通过乐平地区的实测数据分析了阻抗全区视电阻率的可行性,进而论证了电偶源频域电磁测深法阻抗全区视电阻率计算方法在复杂地电条件下的有效性。结果表明,相较于E-E_(x)广域电磁法,由阻抗计算的全区视电阻率可有效压制场源参数的影响,由同源畸变电流引起的电磁场分量误差在比值运算中实现自抵消,大幅降低了由场源附加效应引起的视电阻率偏倚。电偶源频域电磁测深法阻抗全区视电阻率为复杂地电区提供了一种有效的勘探技术手段。 展开更多
关键词 电磁勘探 广域电磁法 全区视电阻率 三维正演 复杂地电模型
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大景深水下广角镜头的光学设计与分析
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作者 高举 王福涔 +7 位作者 董海阔 杨宇杰 王家峥 李训牛 陈洁 余佳桐 刘珂 孙爱平 《红外技术》 北大核心 2026年第1期79-84,共6页
基于水下成像特点,设计了一款大景深水下广角镜头,并采用景深延拓技术,使得水下目标在目标距离3500 mm处保持清晰成像,同时大景深范围内的物体经光学系统成像后仍能保持清晰。其全视场角达90°,焦距为4.92 mm,光学系统总长控制在40... 基于水下成像特点,设计了一款大景深水下广角镜头,并采用景深延拓技术,使得水下目标在目标距离3500 mm处保持清晰成像,同时大景深范围内的物体经光学系统成像后仍能保持清晰。其全视场角达90°,焦距为4.92 mm,光学系统总长控制在40 mm以内。该镜头采用5片标准球面镜片,相比传统7片式结构,显著降低了加工难度和制造成本。该镜头在全视场奈奎斯特频率83 lp/mm处,光学传递函数(Modulation Transfer Function,MTF)均优于0.5,中心视场成像质量接近衍射极限。公差分析及实验验证结果表明,该设计满足低成本量产与装调要求,具备良好的工程应用前景。 展开更多
关键词 水下广角镜头 景深 景深延拓
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广域电磁法在东昆仑哈日扎多金属矿的应用
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作者 钟明峰 王金海 +3 位作者 才智杰 马忠元 林佳富 王亮 《中国有色金属学报》 北大核心 2026年第2期532-547,共16页
广域电磁法(WFEM)作为中深部勘探技术,相较于传统电磁法,具有强抗干扰、高精度、大深度等优点。本文基于东昆仑哈日扎矿区深部成矿斑岩地质体勘查的需求,结合矿区地质和岩(矿)石物性统计成果,建立岩体构造、蚀变矿化带和深部成矿通道的... 广域电磁法(WFEM)作为中深部勘探技术,相较于传统电磁法,具有强抗干扰、高精度、大深度等优点。本文基于东昆仑哈日扎矿区深部成矿斑岩地质体勘查的需求,结合矿区地质和岩(矿)石物性统计成果,建立岩体构造、蚀变矿化带和深部成矿通道的典型地电模型,开展广域电磁法正反演数值模拟研究,分析了该方法的有效性;在Ⅵ号矿带开展WFEM工作,获取了高精度二维电性剖面,查明了矿化带深部展布特征、构造及主要地质体的深部边界与规模。结果表明:哈日扎Ⅵ号矿带深部具有寻找斑岩矿床的巨大潜力,弥补了钻孔深度不足的缺陷;WFEM为哈日扎矿区深部500~2000 m的成矿规律研究和找矿方向提供了物探依据,是金属矿深部探测有效的方法技术。 展开更多
关键词 哈日扎多金属矿 广域电磁法(WFEM) 斑岩体 深部探测
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