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Development of space-based diffractive telescopes Review Article
Wei Zhao, Xin Wang, Hua Liu, Zi-feng Lu, Zhen-wu Lu,wangxin971241@163.com,liuhua_rain@aliyun.com
Frontiers of Information Technology & Electronic Engineering 2020, Volume 21, Issue 6, Pages 809-962 doi: 10.1631/FITEE.1900529
Keywords： 薄膜衍射光学元件；衍射望远系统；超大口径
Xiong-bin PENG, Guo-fang GONG, Hua-yong YANG, Hai-yang LOU, Wei-qiang WU, Tong LIU
Frontiers of Information Technology & Electronic Engineering 2017, Volume 18, Issue 10, Pages 1624-1634 doi: 10.1631/FITEE.1601104
Keywords： Large-scale reflecting telescope Quantitative feedback theory Electro-hydraulic position control system Micron-level position control capability System identification Robust stability
Super-resolution Near-field Optical Imaging and its Industrial Development
Wu Shifa
Strategic Study of CAE 2000, Volume 2, Issue 2, Pages 10-14
The super-resolution near-field optical imaging is an advanced project in the front of high engi-neering science and is an industry that should be developed early in the 21th century in China. In this paper, the historical events and PSTM developments in China are introduced. The imaging expressions of all kinds of the super-resolution near-field optical imaging systems are derived and compared with each others. In general, only with the mode of constant separation of tip-sample may obtain the pure optical image of sample, such as the image of refractive index, reflectivity or transmisivity of sample. The evanescent wave emitted from sample surface and the probe tip smaller than the diffraction limit are the two basic conditions of super-resolution in optical imaging. The other key to obtain the super-resolution is the modulated tip with vertical vibration in the mixture field of evanescent wave and propagating wave in near-field. For the transparent sample PSTM is the best to separate the pure optical image and topography of sampe. The author has applied for two invented patents on PSTM, which will be benificial to the development of PSTM industry in China.
Keywords： super-resolution near-field optics imaging surper resolution optical microscope
Diffractive Deep Neural Networks at Visible Wavelengths Article
Hang Chen, Jianan Feng, Minwei Jiang, Yiqun Wang, Jie Lin, Jiubin Tan, Peng Jin
Engineering 2021, Volume 7, Issue 10, Pages 1485-1493 doi: 10.1016/j.eng.2020.07.032
Optical deep learning based on diffractive optical elements offers unique advantages for parallel processing, computational speed, and power efficiency. One landmark method is the diffractive deep neural network (D2NN) based on three-dimensional printing technology operated in the terahertz spectral range. Since the terahertz bandwidth involves limited interparticle coupling and material losses, this paper
extends D2NN to visible wavelengths. A general theory including a revised formula is proposed to solve any contradictions between wavelength, neuron size, and fabrication limitations. A novel visible light D2NN classifier is used to recognize unchanged targets (handwritten digits ranging from 0 to 9) and targets that have been changed (i.e., targets that have been covered or altered) at a visible wavelength of 632.8 nm. The obtained experimental classification accuracy (84%) and numerical classification accuracy (91.57%) quantify the match between the theoretical design and fabricated system performance. The presented framework can be used to apply a D2NN to various practical applications and design other new applications.
Keywords： Optical computation Optical neural networks Deep learning Optical machine learning Diffractive deep neural networks
Future Research Trend for Improving Large Reflector Antenna Service Performance
Peiyuan Lian, Congsi Wang, Song Xue, Yan Wang, Yuefei Yan, Qian Xu, Baoyan Duan, Na Wang, Yuhu Duan, Yang Wu
Engineering 2021, Volume 7, Issue 8, Pages 1047-1050 doi: 10.1016/j.eng.2021.05.005
Design of the Optical System with Large Relative Aperture and Large Linear Field of View
Pan Junye
Strategic Study of CAE 2000, Volume 2, Issue 8, Pages 89-90
In this paper following discussion the author concluded that the optical system for IR detecting in the distance should be an total reflecting off-axis aspheric system with large relative aperture and large field of view. A system with diameter φ600 mm, f=1000 mm, and linear field of view ± 5° was designed.
Keywords： IR detecting relative aperture large field of view off-axis system aspheric surface
Construction Technology of Shanghai Jinmao Building
Ye Keming,Fan Qingguo
Strategic Study of CAE 2000, Volume 2, Issue 10, Pages 42-49
Shanghai Jinmao building is the 3rd highest building in the world at present. The main building consists of reinforced concrete core wall and exterior structure steel frame. It is rather difficult to construct this edifice in such a poor soil condition in Shanghai. Proceeding from actual facts, Shanghai Construction Groups (SCG) makes efforts to conduct technology innovation, and absorbs advanced experiences domestic and abroad wildly. A unit of unique construction technique and a suitable managing system were developed with the growth of this building. SCG successfully solved a series of construction difficulties including deep-foundation work, mega-columns construction, high - altitude construction and erection, and so on. It only spent 4 years on this building, which set a high-speed record in construction history.
Keywords： Jinmao Building extra-deep slurry wall extra-high building big-size steel tube pile installation of steel structure changeable integrated auto-moving form system
Neutron Diffraction Investigation of the DyFe11Ti Magnetic Structure and Its Spin Reorientations Article
Olivier Isnard, Eder J. Kinast
Engineering 2020, Volume 6, Issue 2, Pages 153-157 doi: 10.1016/j.eng.2019.11.009
In this article, we report on the magnetic structure of DyFe11Ti and its thermal evolution as probed by neutron powder diffraction. A thermodiffraction technique was used to follow the temperature dependence of the magnetic moments, as well as their orientation. The Dy and Fe moments were coupled to each other in an antiparallel manner to form a ferrimagnet, where the easy magnetization direction at 2 K was the [110] axis in the basal (a, b) plane. This magnetic structure underwent two successive spin reorientation phenomena with increasing temperature. A large Dy magnetic moment of 9.7 μB was obtained at low temperatures, and the magnitude decreased rapidly to 7.5 μB at 200 K. The largest Fe magnetic moment was observed on the Fe 8i position. A ThMn12-type crystal structure was preserved in the studied temperature range, despite the large changes of the magnetic structure. A sharp tilt was observed at the first-order spin reorientation, TSR1; the angle between the easy magnetization axis and the crystal c axis was reduced from 90° at 2 K to about 20° at 200 K (where c is the easy axis above 200 K); and the Dy and Fe magnetic moments maintained an antiparallel coupling.
Keywords： Neutron diffraction Magnetic phase diagram Crystal structure
Xiaoping Wang, Weiwei Dong, Peng Zhang, Haoqi Tang, Lanting Zhang, Tieying Yang, Peng Liu, Hong Wang, X.-D. Xiang
Engineering 2022, Volume 10, Issue 3, Pages 81-88 doi: 10.1016/j.eng.2021.05.023
High-throughput powder X-ray diffraction (XRD) with white X-ray beam and an energy-dispersive detector array are demonstrated in this work on a CeO2 powder sample on a bending magnet synchrotron beamline at the Shanghai Synchrotron Radiation Facility (SSRF), using a simulated energy-dispersive array detector consisting of a spatially scanning silicon-drift detector (SDD). Careful analysis and corrections are applied to account for various experimental hardware-related and diffraction angle-related factors. The resulting diffraction patterns show that the relative strength between different diffraction peaks from energy-dispersive XRD (EDXRD) spectra is consistent with that from angle-resolved XRD (ARXRD), which is necessary for analyzing crystal structures for unknown samples. The X-ray fluorescence (XRF) signal is collected simultaneously. XRF counts from all pixels are integrated directly by energy, while the diffraction spectra are integrated by d-spacing, resulting in a much improved peak strength and signal-to-noise (S/N) ratio for the array detector. In comparison with ARXRD, the diffraction signal generated by a white X-ray beam over monochromic light under the experimental conditions is about 104 times higher. The full width at half maximum (FWHM) of the peaks in q-space is found to be dependent on the energy resolution of the detector, the angle span of the detector, and the diffraction angle. It is possible for EDXRD to achieve the same or even smaller FWHM as ARXRD under the energy resolution of the current detector if the experimental parameters are properly chosen.
Keywords： High-throughput experiment White beam X-ray diffraction Energy-dispersive array detector Energy-dispersive X-ray diffraction Angle-resolved X-ray diffraction
Ultra-Precision Machining Technology and Equipment for High-End Optical Elements
Jiang Zhuangde, Li Changsheng , Sun Lin, Duan Duanzhi, Kang Chengwei ,Chen Shanshan, Lin Qijing, Yang Shuming
Strategic Study of CAE 2023, Volume 25, Issue 1, Pages 131-141 doi: 10.15302/J-SSCAE-2023.07.003
High-end optical elements determine the performance of high-end equipment. Researching the ultra-precision machining technology and equipment for high-end optical elements is crucial for strengthening China's manufacturing industry and satisfying the requirements of the high-end equipment industry. In this study, the ultra-precision machining methods and equipment for optical elements, high-performance basic components, and measurement methods and equipment used in ultra-precision optical machining are analyzed. Five development trends are summarized including extremalization of precision and size, integration of shape and performance, compounding of machining technologies, integration of machining and measurement, and intellectualization of equipment and processes. Through extensive survey and discussions, a technology roadmap for ultra-precision manufacturing of high-end optical elements by 2035 is proposed from the aspects of demand, goals, products, key technologies, application demonstrations, and guarantees. Furthermore, several development suggestions are proposed, including (1) optimizing the innovation system and establishing technical alliances by organizing superior resources, (2) increasing resource guarantees and laying out plans on basic and technical research,(3) strengthening talent cultivation to expand the scale of the multi-level talent team, and (4) building a solid foundation for industrial development and cultivating small-sized leading enterprises.
Keywords： optical element precision manufacturing ultra-precision machine tool ultra-precision machining optical fabrication
FAST: The Five-Hundred-Meter Aperture Spherical Radio Telescope
Peng Jiang, Hengqian Gan, Rui Yao, Jinghai Sun, Jiguang Lu, Dongjun Yu, Hui Li, Jinglong Yu, Bin Dong, Xiaoming Chai, Jianing Yin
Engineering 2023, Volume 28, Issue 9, Pages 21-25 doi: 10.1016/j.eng.2023.04.001
Fluorescence nanoscopy in neuroscience Review
Yangyundou Wang,Jian Lin,Qiming Zhang,Xi Chen,Haitao Luan,Min Gu
Engineering 2022, Volume 16, Issue 9, Pages 29-38 doi: 10.1016/j.eng.2020.11.010
Fluorescence nanoscopy provides imaging techniques that overcome the diffraction-limited resolution barrier in light microscopy, thereby opening up a new area of research in biomedical imaging in fields such as neuroscience. Here, we review the foremost fluorescence nanoscopy techniques, including descriptions of their applications in elucidating protein architectures and mobility, the real-time determination of synaptic parameters involved in neural processes, three-dimensional imaging, and the tracking of nanoscale neural activity. We conclude by discussing the prospects of fluorescence nanoscopy, with a particular focus on its deployment in combination with related techniques (e.g., machine learning) in neuroscience.
Keywords： Fluorescence imaging Diffraction limit Nanoscale resolution Neuroscience
Stiction and Friction in Micro Electro Mechanical Systems
Wang Weiyuan
Strategic Study of CAE 2000, Volume 2, Issue 3, Pages 36-41
The stiction and friction influencing the yield and reliability of MEMS are reviewed in this paper.The stiction, called release-related stiction, can occur within micron gaps of Si microstuctures during the etching of sacrifacial layer by HF and drying. It can also occur after packaging of the device due to over range of input signals and is called in-use stiction. It is concluded that the capillary force of water between two Si hydrophilic surfaces at separation gap of micron is the major contributor to the release-related stiction. The origin of in-use adhesion is from the chemical state of Si surface. Coating of anti-stiction films on the surface of Si microstructures and packaging of devices under dry atmosphere or vacuum are the most important methods to prevent the in MEMS devices from stiction. The preparation technology of anti-stiction films and its problems are described. Comparing with stiction, the friction is more complex. The commercially produced accelerometers and digital mirror devices are the devices with no direct contact friction. After using anti-stiction films, the stiction is fully prevented, and even the friction is apparently decreased. However, friction still exists in MEMS of direct contact moving parts. The wear resoluted from friction will decrease the reliability and lifetime of the devices. To fabricate the films with anti-stiction and wear-resitsting ability are the key research projects in high speed moving MEMS devices.
Keywords： micro electro mechanical systems stiction friction anti-stiction films wear-resisting films
Development of High-Pressure Multigrain X-Ray Diffraction for Exploring the Earth’s Interior Review
Li Zhang, Hongsheng Yuan, Yue Meng, Ho-kwang Mao
Engineering 2019, Volume 5, Issue 3, Pages 441-447 doi: 10.1016/j.eng.2019.02.004
The lower mantle makes up more than a half of our planet’s volume. Mineralogical and petrological experiments on realistic bulk compositions under high pressure–temperature (P–T) conditions are essential for understanding deep mantle processes. Such high P–T experiments are commonly conducted in a laser-heated diamond anvil cell, producing a multiphase assemblage consisting of 100 nm to submicron crystallite grains. The structures of these lower mantle phases often cannot be preserved upon pressure quenching; thus, in situ characterization is needed. The X-ray diffraction (XRD) pattern of such a multiphase assemblage usually displays a mixture of diffraction spots and rings as a result of the coarse grain size relative to the small X-ray beam size (3–5 μm) available at the synchrotron facilities. Severe peak overlapping from multiple phases renders the powder XRD method inadequate for indexing new phases and minor phases. Consequently, structure determination of new phases in a high P–T multiphase assemblage has been extremely difficult using conventional XRD techniques. Our recent development of multigrain XRD in high-pressure research has enabled the indexation of hundreds of individual crystallite grains simultaneously through the determination of crystallographic orientations for these individual grains. Once indexation is achieved, each grain can be treated as a single crystal. The combined crystallographic information from individual grains can be used to determine the crystal structures of new phases and minor phases simultaneously in a multiphase system. With this new development, we have opened up a new area of crystallography under the high P–T conditions of the deep lower mantle. This paper explains key challenges in studying multiphase systems and demonstrates the unique capabilities of high-pressure multigrain XRD through successful examples of its applications.
Keywords： High pressure Synchrotron X-ray Multigrain Diamond anvil cell Minerals Petrology Earth’s interior
Transparent Thermally Tunable Microwave Absorber Prototype Based on Patterned VO2 Film Article
Zhengang Lu, Yilei Zhang, Heyan Wang, Chao Xia, Yunfei Liu, Shuliang Dou, Yao Li, Jiubin Tan
Engineering 2023, Volume 29, Issue 10, Pages 198-206 doi: 10.1016/j.eng.2022.10.005
Transparent microwave absorbers that exhibit high optical transmittance and microwave absorption capability are ideal, although having a fixed absorption performance limits their applicability. Here, a simple, transparent, and thermally tunable microwave absorber is proposed, based on a patterned vanadium dioxide (VO2) film. Numerical calculations and experiments demonstrate that the proposed VO2 absorber has a high optical transmittance of 84.9% at 620 nm; its reflection loss at 15.06 GHz can be thermally tuned from –4.257 to –60.179 dB, and near-unity absorption is achieved at 523.75 K. Adjusting only the patterned VO2 film duty cycle can change the temperature of near-unity absorption. Our VO2 absorber has a simple composition, a high optical transmittance, a thermally tunable microwave absorption performance, a large modulation depth, and an adjustable temperature tuning range, making it promising for application in tunable sensors, thermal emitters, modulators, thermal imaging, bolometers, and photovoltaic devices.
Keywords： Tunable microwave absorber VO2 film Optical transparent Near unity absorption Large modulation depth
Title Author Date Type Operation
Development of space-based diffractive telescopes
Wei Zhao, Xin Wang, Hua Liu, Zi-feng Lu, Zhen-wu Lu,wangxin971241@163.com,liuhua_rain@aliyun.com
Journal Article
Quantitative feedback controller design and test for an electro-hydraulic position control system in a large-scale reflecting telescope
Xiong-bin PENG, Guo-fang GONG, Hua-yong YANG, Hai-yang LOU, Wei-qiang WU, Tong LIU
Journal Article
Diffractive Deep Neural Networks at Visible Wavelengths
Hang Chen, Jianan Feng, Minwei Jiang, Yiqun Wang, Jie Lin, Jiubin Tan, Peng Jin
Journal Article
Future Research Trend for Improving Large Reflector Antenna Service Performance
Peiyuan Lian, Congsi Wang, Song Xue, Yan Wang, Yuefei Yan, Qian Xu, Baoyan Duan, Na Wang, Yuhu Duan, Yang Wu
Journal Article
Design of the Optical System with Large Relative Aperture and Large Linear Field of View
Pan Junye
Journal Article
Neutron Diffraction Investigation of the DyFe11Ti Magnetic Structure and Its Spin Reorientations
Olivier Isnard, Eder J. Kinast
Journal Article
High-Throughput Powder Diffraction Using White X-Ray Beam and a Simulated Energy-Dispersive Array Detector
Xiaoping Wang, Weiwei Dong, Peng Zhang, Haoqi Tang, Lanting Zhang, Tieying Yang, Peng Liu, Hong Wang, X.-D. Xiang
Journal Article
Ultra-Precision Machining Technology and Equipment for High-End Optical Elements
Jiang Zhuangde, Li Changsheng , Sun Lin, Duan Duanzhi, Kang Chengwei ,Chen Shanshan, Lin Qijing, Yang Shuming
Journal Article
FAST: The Five-Hundred-Meter Aperture Spherical Radio Telescope
Peng Jiang, Hengqian Gan, Rui Yao, Jinghai Sun, Jiguang Lu, Dongjun Yu, Hui Li, Jinglong Yu, Bin Dong, Xiaoming Chai, Jianing Yin
Journal Article
Fluorescence nanoscopy in neuroscience
Yangyundou Wang,Jian Lin,Qiming Zhang,Xi Chen,Haitao Luan,Min Gu
Journal Article
Development of High-Pressure Multigrain X-Ray Diffraction for Exploring the Earth’s Interior
Li Zhang, Hongsheng Yuan, Yue Meng, Ho-kwang Mao
Journal Article
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