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Design and fabrication of polymeric multimode power splitter with secondary asymmetric branches

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Chinese Optics Letters 2011年第8期9卷 41-44页

作者：李书林巧陈柳华吴兴坤 State Key Laboratory of Modern optical Instrumentation Department of Optical EngineeringZhejiang University

A novel design of multimode light power splitter is proposed and fabricated by using secondary asymmet- ric Y branches. An almost equMly divided output among output terminals is obtained experimentally. Maskless laser direct writing technique is applied in the fabrication process to facilitate the formation of power splitters by ultraviolet curable polymer. The analysis of the performances of both four-port and eight-port devices shows that these two dividers obtain a power splitting uniformity of more than 95%.

关键词： Fabrication Ultraviolet lasers

Investigations of range accuracy for long-range three-dimensional active imaging

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Chinese Optics Letters 2011年第6期9卷 48-50页

作者：张秀达严惠民周琴 State Key Laboratory of Modern optical Instrument National Engineering Research Center for Optical Instrument Optical Engineering Department Zhejiang University

Distance resolutions and noises are analyzed experimentally for long-range three-dimensional （3D） active imaging systems that have signal-to-noise ratios （SNRs） more optimal than 30：1. Findings indicate that the photon shot noise primarily determines the SNR. However, the active imaging method, which has a relatively low SNR, generates a relatively high distance resolution. To explain this phenomenon, a theory in which the distance resolution of 3D active imaging systems is determined by both the photon shot noise and the subinterval width is developed. Theoretical and experimental results differ by less than 4%.

关键词： Imaging systems Photons Shot noise Signal to noise ratio

Simple PSF based method for pupil phase mask’s optimization in wavefront coding system

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第2期8卷 180-185页

作者： ZHANG Wen-zi CHEN Yan-ping ZHAO Ting-yu YE Zi YU Fei-hong State Key Laboratory of Modern optical Instrumentation Optical Engineering Department Zhejiang University Hangzhou 310027 China

By applying the wavefront coding technique to an optical system, the depth of focus can be greatly increased. Several complicated methods, such as Fisher Information based method, have already been taken to optimize for the best pupil phase mask in ideal condition. Here one simple point spread function (PSF) based method with only the standard deviation method used to evaluate the PSF stability over the depth of focus is taken to optimize for the best coefficients of pupil phase mask in practical optical systems. Results of imaging simulations for optical systems with and without pupil phase mask are presented, and the sharpness of image is calculated for comparison. The optimized results showed better and much more stable imaging quality over the original system without changing the position of the image plane.

关键词： Wavefront coding Pupil phase mask Depth of focus PSF stability Optimization Sharpness Imaging simulation

Non-invasive Observation of Human Tissue Samples with Full Field optical Coherence Tomography

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Chinese Journal of Electronics 2019年第5期28卷 987-992页

作者： MU Ning GAO Wanrong ZHOU Yawen department of optical Engineering Nanjing University of Science and Technology

In this work, we report on non-invasive observation of human esophagus, liver, and uterus samples with Full field optical coherence tomography(FFOCT).ln imaging process, fresh human samples were fixed in formalin immediately after excision and then imaged directly without staining and cutting the samples into a serial of thin slices. Tissue microstructures of each type of normal or cancerous tissue as well as their changes with the increase of the depth beneath tissue surface can be identified in the depth-resolved images. The results demonstrate the potential of applications of the en face images in clinic practice.

关键词： En face images optical sectioning imaging Full field optical coherence tomography(FFOCT) Tissue microstructures

Optimal design of RTCs in digital circuit fault self-repair based on global signal optimization

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Chinese Journal of Aeronautics 2016年第6期29卷 1774-1787页

作者： Zhang Junbin Cai Jinyan Meng Yafeng department of Electronic and optical Engineering Mechanical Engineering College

Since digital circuits have been widely and thoroughly applied in various fields, electronic systems are increasingly more complicated and require greater reliability. Faults may occur in electronic systems in complicated environments. If immediate field repairs are not made on the faults, electronic systems will not run normally, and this will lead to serious losses. The traditional method for improving system reliability based on redundant fault-tolerant technique has been unable to meet the requirements. Therefore, on the basis of(evolvable hardware)-based and(reparation balance technology)-based electronic circuit fault self-repair strategy proposed in our preliminary work, the optimal design of rectification circuits(RTCs) in electronic circuit fault self-repair based on global signal optimization is deeply researched in this paper. First of all, the basic theory of RTC optimal design based on global signal optimization is proposed. Secondly, relevant considerations and suitable ranges are analyzed. Then, the basic flow of RTC optimal design is researched. Eventually, a typical circuit is selected for simulation verification, and detailed simulated analysis is made on five circumstances that occur during RTC evolution. The simulation results prove that compared with the conventional design method based RTC, the global signal optimization design method based RTC is lower in hardware cost, faster in circuit evolution, higher in convergent precision, and higher in circuit evolution success rate. Therefore, the global signal optimization based RTC optimal design method applied in the electronic circuit fault self-repair technology is proven to be feasible, effective, and advantageous.

关键词： Evolutionary algorithm Evolvable hardware Fault self-repair Optimal design Reparation balance technology

Fault self-repair strategy based on evolvable hardware and reparation balance technology

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Chinese Journal of Aeronautics 2014年第5期27卷 1211-1222页

作者： Zhang Junbin Cai Jinyan Meng Yafeng Meng Tianzhen department of Electronic and optical Engineering Mechanical Engineering College

In the face of harsh natural environment applications such as earth-orbiting and deep space satellites, underwater sea vehicles, strong electromagnetic interference and temperature stress,the circuits faults appear easily. Circuit faults will inevitably lead to serious losses of availability or impeded mission success without self-repair over the mission duration. Traditional fault-repair methods based on redundant fault-tolerant technique are straightforward to implement, yet their area, power and weight cost can be excessive. Moreover they utilize all plug-in or component level circuits to realize redundant backup, such that their applicability is limited. Hence, a novel selfrepair technology based on evolvable hardware（EHW） and reparation balance technology（RBT） is proposed. Its cost is low, and fault self-repair of various circuits and devices can be realized through dynamic configuration. Making full use of the fault signals, correcting circuit can be found through EHW technique to realize the balance and compensation of the fault output-signals. In this paper, the self-repair model was analyzed which based on EHW and RBT technique, the specific self-repair strategy was studied, the corresponding self-repair circuit fault system was designed, and the typical faults were simulated and analyzed which combined with the actual electronic devices. Simulation results demonstrated that the proposed fault self-repair strategy was feasible. Compared to traditional techniques, fault self-repair based on EHW consumes fewer hardware resources, and the scope of fault self-repair was expanded significantly.

关键词： Evolutionary algorithm Evolvable hardware Fault Self-repair Fault-tolerant Genetic algorithm particle swarm optimization Reparation balance technology

Near-Field Characterization of optical Micro/Nanofibres

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Chinese Physics Letters 2007年第10期24卷 3006-3008页

作者：马哲王姗姗杨青童利民 State Key Laboratory of Modern optical Instrumentation Department of Optical Engineering Zhejiang University Hangzhou 310027

Near-field scanning optical microscopy is used to investigate the waveguiding properties of optical micro/nanofibres （MNFs） by means of detecting optical power carried by evanescent waves. Taper drawn silica and tellurite MNFs, supported on low-index substrates, are used to guide a 532-nm-wavelength light beam for the test. Modification of the single-mode condition of the MNF in the presence of a substrate is observed. Spatial modulation of the longitudinal field intensity （with a 195-nm period） near the output end of a 760-nm-diameter silica MNF is well resolved. Energy exchange through evanescent coupling between two parallel MNFs is also investigated.

关键词： SUBWAVELENGTH PHOTONICS INTEGRATION CHANNEL WAVE-GUIDES SILICA NANOWIRES DIAMETER SILICA MICROSCOPY

Embryonic array configuration optimization method based on reliability and hardware consumption

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Chinese Journal of Aeronautics 2019年第3期32卷 639-652页

作者： Tao WANG Jinyan CAI Yafeng MENG Sai ZHU department of Electronic and optical Engineering Army Engineering University

Embryonic Array(EA) with different configuration methods will directly affect its reliability and hardware consumption. At present, EA configuration design is lack of quantitative analysis method. In order to reasonably optimize EA configuration design, an EA configuration optimization design method is proposed, which is based on the constraints of EA hardware consumption and reliability. Through the analysis of EA working process and composition, quantitative analysis of EA reliability and hardware consumption are completed. Based on the constraints of EA hardware consumption and reliability, the mathematical model of EA configuration optimization design is established, which transfers EA configuration optimization design into an integer nonlinear programming model problem. According to the difference of the fitness value of individual waiting for mutation in population, adaptive mutation operator and crossover operator are selected, and a novel Modified Adaptive Differential Evolution(MADE) algorithm is proposed,which is used to solve EA configuration optimization design problem. Simulation experiments and analysis indicate that the MADE is able to effectively improve the speed, accuracy and stability of algorithm. Moreover, the proposed EA configuration optimization design method can select the most reasonable EA configuration design, and play an important guiding role in EA optimization design.

关键词： Configuration optimization Differential evolution Embryonic electronic Hardware consumption Integer nonlinear programming model Reliability Self-repairing

Numerical Simulation of Bell Inequality＇s Violation Using optical Transverse Modes in Multimode Waveguides

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Chinese Physics Letters 2008年第7期25卷 2350-2353页

作者：符建高淑娟 State Key Lab of Modern optical Instrumentation Department of Optical Engineering Zhejiang University Hangzhou 310027

We numerically demonstrate that ＇mode-entangled states＇ based on the transverse modes of classical optical fields in multimode waveguides violate Bell＇s inequality. Numerically simulating the correlation measurement scheme of Bell＇s inequality, we obtain the normalized correlation functions of the intensity fluctuations for the two entangled classical fields. By using the correlation functions, the maximum violations of Bell＇s inequality are obtained. This implies that the two classical fields in the mode-entangled states, although spatially separated, present a nonlocal correlation.

关键词： BEAM-PROPAGATION METHOD QUANTUMLIKE FIELDS PHOTON MEDIA