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Towards automatic freeform optics design: coarse and fine search of the three-mirror solution space

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Light(Science & Applications) 2021年第4期10卷 660-670页

作者： Benqi Zhang guofan jin Jun Zhu State Key Laboratory of Precision Measurement Technology and Instruments Departm ent of Precision InstrumentTsinghua UniversityBeijing 100084China

Design of an optical system,whether classic or novel,in the past or the present,requires significant effort from the *** addition to design methods and theories,the designer’s skills and experience in optical system design are particularly important,which may require years of practice to *** diversity and variety of results are limited because of the difficulty,time,and labor costs *** this article,we propose an automatic design method for freeform optics that can achieve a diverse range of three-mirror *** optical specifications and the design constraints are the only inputs required,and a variety of results can be obtained *** output results have various structures and various optical power distributions with high imaging *** implementing the design method,designers can not only realize an overview of the solution space of the three-mirror freeform system,but can also focus on specific designs.

关键词： mirror optics system

Single-shot lensless imaging with fresnel zone aperture and incoherent illumination

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Light(Science & Applications) 2020年第1期9卷 1509-1519页

作者： Jiachen Wu Hua Zhang Wenhui Zhang guofan jin Liangcai Cao George Barbastathis State Key Laboratory of Precision Measurement Technology and Instruments Department of Precision InstrumentsTsinghua University100084 BeijingChina Department of Mechanical Engineering Massachusetts Institute of Technology77 Massachusetts AvenueCambridgeMA 02139USA

Lensless imaging eliminates the need for geometric isomorphism between a scene and an image while allowing the construction of compact,lightweight imaging ***,a challenging inverse problem remains due to the low reconstructed signal-to-noise *** implementations require multiple masks or multiple shots to denoise the *** propose single-shot lensless imaging with a Fresnel zone aperture and incoherent *** using the Fresnel zone aperture to encode the incoherent rays in wavefront-like form,the captured pattern has the same form as the inline *** conventional backpropagation reconstruction is troubled by the twin-image problem,we show that the compressive sensing algorithm is effective in removing this twin-image artifact due to the sparsity in natural *** reconstruction with a significantly improved signal-to-noise ratio from a single-shot image promotes a camera architecture that is flat and reliable in its structure and free of the need for strict calibration.

关键词： illumination Fresnel removing

Method of lateral image reconstruction in structured illumination microscopy with super resolution

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Journal of Innovative Optical Health Sciences 2016年第3期9卷 4-18页

作者： Qiang Yang Liangcai Cao Hua Zhang Hao Zhang guofan jin State Key Laboratory of Precision Measurement Technology and Instruments Tsinghua University Beijing 100084P.R.China

The image reconstruction process in super-resolution structured illumination microscopy(SIM)is *** structured pattern is generated by the interference of two Gaussian beams to encode undetectable spectra into detectable region of *** parameters estimation of the structured pattern,the encoded spectra are computationally decoded and recombined in Fourier domain to equivalently increase the cut-off frequency of microscope,resulting in the extension of detectable spectra and a reconstructed image with about two-fold enhanced *** di®erent methods to estimate the initial phase of structured pattern are compared,verifying the auto-correlation algorithm a®ords the fast,most precise and robust *** artifacts sources and detailed reconstruction°owchart for both linear and nonlinear SIM are also presented.

关键词： Microscopy structured illumination super-resolution image reconstruction

Quasi-Dammann grating with proportional intensity of array spots for surface hardening of metal

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Science China(Physics,Mechanics & Astronomy) 2011年第1期54卷 79-83页

作者： LI ShaoXia TAN QiaoFeng YU Gang WANG HengHai jin guofan Key Laboratory of Mechanics in Advanced Manufacturing Institute of Mechanics Chinese Academy of Sciences Beijing 100190 China State Key Laboratory of Precision Measurement Technology and Instruments Tsinghua University Beijing 100084 China The 14th Research Institute China Electronics Technology Group Corporation Nanjing 210039 China

For surface hardening of metal,a quasi-Dammann grating (QDG) is proposed and fabricated to generate array spots with proportional-intensity *** get uniformly hardened band distribution and improve the wear resistance of the sample surface,a three-order QDG is designed to produce array spots with enhanced intensity in the *** design and fabrication of the QDG are described in *** surface profile of the fabricated grating was measured,which shows that the fabrication error is less than 2%.The laser beam intensity distribution shaped by the QDG was tested by a laser beam analyzer to verify the validity of the *** application of the QDG in the laser surface hardening of metal was experimentally investigated,and the results show that the hardness distribution of the modified layer and the wear resistance of the sample surface are improved significantly by using the QDG.

关键词：表面硬化强度分布达曼光栅金属表面阵列制造误差测试分析仪边缘增强

维普期刊数据库

Helicity dependent directional surface plasmon polariton excitation using a metasurface with interfacial phase discontinuity

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Light(Science & Applications) 2013年第1期2卷 197-203页

作者： Lingling Huang Xianzhong Chen Benfeng Bai Qiaofeng Tan guofan jin Thomas Zentgraf Shuang Zhang School of Physics&Astronomy University of BirminghamBirmingham B152TTUK State Key Laboratory of Precision Measurement Technology and Instruments Department of Precision InstrumentsTsinghua UniversityBeijing 100084China Department of Physics University of PaderbornD-33098 PaderbornGermany

Surface plasmon polaritons(SPPs)have been widely exploited in various scientific communities,ranging from physics,chemistry to biology,due to the strong confinement of light to the metal *** many applications,it is important that the free space photon can be coupled to SPPs in a controllable *** this Letter,we apply the concept of interfacial phase discontinuity for circularly polarizations on a metasurface to the design of a novel type of polarization-dependent SPP unidirectional excitation at normal *** unidirectional excitation of SPPs along opposite directions is experimentally demonstrated at optical frequencies by simply switching the helicity of the incident *** approach,in conjunction with dynamic polarization modulation techniques,opens gateway towards integrated plasmonic circuits with electrically reconfigurable functionalities.

关键词： metamaterials metasurface surface plasmon

Diffractive optical elements 75 years on:from micro-optics to metasurfaces

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Photonics Insights 2023年第4期2卷 43-101页

作者： Qiang Zhang Zehao He Zhenwei Xie Qiaofeng Tan Yunlong Sheng guofan jin Liangcai Cao Xiaocong Yuan Nanophotonics Research Center Institute of Microscale Optoelectronics&State Key Laboratory of Radio Frequency Heterogeneous IntegrationShenzhen UniversityShenzhenChina Department of Precision Instruments Tsinghua UniversityBeijingChina Center for Optics Photonics and LasersLaval UniversityQuebecCanada Research Institute of Intelligent Sensing Research Center for Humanoid SensingZhejiang LabHangzhouChina

Diffractive optical elements(DOEs)are intricately designed devices with the purpose of manipulating light fields by precisely modifying their *** concept of DOEs has its origins dating back to 1948 when *** first introduced ***,researchers introduced binary optical elements(BOEs),including computer-generated holograms(CGHs),as a distinct category within the realm of *** was the first revolution in optical *** next major breakthrough in light field manipulation occurred during the early 21st century,marked by the advent of metamaterials and *** are particularly appealing due to their ultra-thin,ultra-compact properties and their capacity to exert precise control over virtually every aspect of light fields,including amplitude,phase,polarization,wavelength/frequency,angular momentum,*** advancement of light field manipulation with micro/nano-structures has also enabled various applications in fields such as information acquisition,transmission,storage,processing,and *** this review,we cover the fundamental science,cutting-edge technologies,and wide-ranging applications associated with micro/nano-scale optical devices for regulating light *** also delve into the prevailing challenges in the pursuit of developing viable technology for real-world ***,we offer insights into potential future research trends and directions within the realm of light field manipulation.

关键词： diffractive optical elements metasurfaces metamaterials

Invariant Joint Transform CorrelatorⅠ: Mapping Filter

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Chinese Journal of Lasers 1997年第1期B6卷 64-70页

作者： FENG Jihong WU Minxian jin guofan YAN Shuhua(Tainghua University, Precision Department,100084 Beijing, China) Tsinghua Univ Beijing China

A joint transform correlator incorporating coordinate transformation technique is propescd to perform invariant pattern recognition. Instead of an input image or its Fourier transform intensity, the Fourier transform of the input image is directly transformed from rectangular into logarithmic-polar coordinate. All of information is saved, and as a result, multiple objects can be proceased simulataneously. A binary optical component is designed and fabricated to perform coordinate transformation in high efficiency.

关键词： invariant optical pattern recognition cyclic shift joint transform correlator binary optical component

A　Optical　Scheme　for　Parallelly　Realizing　the　Morphological　Erosion　of　1－D　Gray　Images

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Chinese Journal of Lasers 1996年第3期B5卷 282-288页

作者： HUANG Guoliang jin guofan WU Minxian YAN Yingbai(Dept. of Precision Instruments, Tsinghua University, Beijing 100084) Tsinghua Univ Beijing China

Ａ　Ｏｐｔｉｃａｌ　Ｓｃｈｅｍｅ　ｆｏｒ　Ｐａｒａｌｌｅｌｌｙ　Ｒｅａｌｉｚｉｎｇ　ｔｈｅ　Ｍｏｒｐｈｏｌｏｇｉｃａｌ　Ｅｒｏｓｉｏｎ　ｏｆ　１－Ｄ　Ｇｒａｙ　ＩｍａｇｅｓＡＯｐｔｉｃａｌＳｃｈｅｍｅｆｏｒＰａｒａｌ... 详细信息

Ａ　Ｏｐｔｉｃａｌ　Ｓｃｈｅｍｅ　ｆｏｒ　Ｐａｒａｌｌｅｌｌｙ　Ｒｅａｌｉｚｉｎｇ　ｔｈｅ　Ｍｏｒｐｈｏｌｏｇｉｃａｌ　Ｅｒｏｓｉｏｎ　ｏｆ　１－Ｄ　Ｇｒａｙ　ＩｍａｇｅｓＡＯｐｔｉｃａｌＳｃｈｅｍｅｆｏｒＰａｒａｌｌｅｌｌｙＲｅａｌｉｚｉｎｇｔｈｅ...

关键词： mathematical morphology digital umbra sheding shadowing algorithm

Texture Image Segmentation Using Talbot Effect

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Chinese Journal of Lasers 1995年第3期B4卷 281-286页

作者： WANG Wenlu jin guofan YAN Yingbai WU Minxian(Dept. of Precision Instruments, Tsinghua University, 100084, Beijing, China) Tsinghua Univ Beijing China

ＴｅｘｔｕｒｅＩｍａｇｅＳｅｇｍｅｎｔａｔｉｏｎＵｓｉｎｇＴａｌｂｏｔＥｆｆｅｃｔ￥ＷＡＮＧＷｅｎｌｕ；ＪＩＮＧｕｏｆａｎ；ＹＡＮＹｉｎｇｂａｉ；ＷＵＭｉｎｘｉａｎ（Ｄｅｐｔ．ｏｆＰｒｅｃｉｓｉｏｎＩｎｓｔｒｕｍｅｎ... 详细信息

ＴｅｘｔｕｒｅＩｍａｇｅＳｅｇｍｅｎｔａｔｉｏｎＵｓｉｎｇＴａｌｂｏｔＥｆｆｅｃｔ￥ＷＡＮＧＷｅｎｌｕ；ＪＩＮＧｕｏｆａｎ；ＹＡＮＹｉｎｇｂａｉ；ＷＵＭｉｎｘｉａｎ（Ｄｅｐｔ．ｏｆＰｒｅｃｉｓｉｏｎＩｎｓｔｒｕｍｅｎｔｓ，ＴｓｉｎｇｈｕａＵｎｉｖｅｒ...

关键词： Talbot effect texture segmentation