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Chinese Optics Letters 2012年第11期10卷 80-82页

作者：孔德明李岩王慧伍剑林金桐 State Key Laboratory of Information Photonics and optical Communications Beijing University of Posts and Telecommunications

An all-optical serial-to-parallel converter （SPC） utilizing two cascaded phase modulators and optical bandpass filters （OBPFs） is experimentally investigated and applied to demultiplex an 80-GBd optical timedivision multiplexing （OTDM） return-to-zero （RZ） differential quadrature phase-shift keying （QPSK） signal. Two 40-GBd OTDM tributaries are error-free demultiplexed with a power penalty of approximately 4 dB in the worst case. With its advantages of compact structure, high speed, low power penalty, simultaneous two-tributary operation, and no assistance from a light source, the SPC has potential for use in future OTDM networks. However, the performance of the SPC still needs imDrovement.

关键词： Bandpass filters Light sources Low power electronics optical filters Quadrature phase shift keying Time division multiplexing

Stable multi-wavelength erbium-doped fiber laser based on dispersion-shifted fiber and Sagnac loop filter

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Chinese Optics Letters 2007年第9期5卷 519-521页

作者：高莹陈达如高士明 Centre for optical and Electromagnetic Research State Key Laboratory of Modern Optical InstrumentationZhejiang University

A multi-wavelength erbium-doped fiber laser （MEDFL） with simple line structure is experimentally demonstrated by using a Sagnac interferometer as a comb filter. It is shown that the multi-wavelength lasing is quite stable at room temperature due to the four-wave mixing （FWM） effect among different laser channels in the dispersion-shifted fiber cooperated in the laser cavity.

关键词： Electromagnetic dispersion Four wave mixing Interferometers optical fibers optical filters Wavelength

Image recognition of laser radar using linear SVM correlation filter

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Chinese Optics Letters 2007年第9期5卷 549-551页

作者：孙剑峰李琦陆威王骐 National Key Laboratory of Tunable Laser Technology Institute of OptoelectronicsHarbin Institute of Technology

Through deducing the relationship between support vector machine （SVM） and correlation principle, the optimal hyperplane is proved as a correlation filter when the kernel function is the linear kernel. So a new correlation filter, named linear SVM correlation filter （LSCF）, is proposed. The filter has not only shift-invariance, but also SVM properties. The real images of laser radar are used as experiment data, and LSCF is used to solve the in-plane rotation invariance. The results show that the filter can recognize the different rotated objects, and the correlation output is stable. The filter is insensitive to the noise and gray change, and has good discrimination ability. In the same design way, LSCF is also suitable to solve other problems of correlation distortion.

关键词： Distortion (waves) optical filters optical radar Support vector machines

Novel optical packet with non-return-to-zero label and duobinary carrier-suppressed return-to-zero payload

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Chinese Optics Letters 2008年第2期6卷 96-99页

作者：邱昆凌云 Key Laboratory of Broadband optical Fiber Transmission and Communication Networks University of Electronic Science and Technology of China

A novel packet format with non-return-to-zero （NRZ） label and duobinary carrier-suppressed return-to-zero （DCS-RZ） payload is proposed for optical packet switching networks. NRZ label is followed by DCS-RZ payload with a certain guard time. The spectra of the low-rate NRZ label locate around the optical carrier frequency where some parts of the corresponding spectra of the high-rate DCS-RZ payload have been suppressed due to DCS-RZ modulation. At the switching node, the label or payload extraction can be realized simply through an optical bandpass or notch filter respectively. The feasibility of the scheme is verified by the simulation on the famous photonic design platform designed by Virtual Photonics Inc. （VPI）. The effects of optical filter bandwidth on the received signal quality are discussed by analyzing bit error rate （BER） and contrast ratio performances.

关键词： Bandwidth Bit error rate Computer simulation Notch filters optical filters Switching networks

Optimizing the optical field distribution of solid immersion lens system by a continuous phase filter

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Chinese Optics Letters 2007年第6期5卷 318-321页

作者：叶雪华张耀举陈俊峰 College of Physics and Electronic Information Wenzhou University

In solid immersion lens （SIL） microscopy systems with high numerical aperture （NA）, there always exists the aberration produced by Fresnel effects at the interface between SIL and the sample. This aberration may cause the degradation of the image of sample. We design a continuous phase filter and optimize the optical field distribution of SIL system. The numerical results show that when the continuous phase filter is used, the field distribution of SIL system can be optimized, and the focal depth and intensity of transmitted light can be increased. At the same time, the intensity of side-lobe and the resolution are kept almost unchanged.

关键词： Aberrations optical filters

Control of disability glare by means of electrochromic filtering glasses:A pilot study

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Journal of Innovative optical Health Sciences 2017年第1期10卷 11-20页

作者： Rosa Maria Coco-Martín Ruben Cuadrado-Asensio Ceesar Vega-Colado Ricardo Vergaz Jose M.Sanchez-Pena Ana Viñuales Sergi Peris Pau Artús M.Begona Coco-Martín IOBA Universidad de ValladolidValladolidSpain GDAF-UC3M Grupo de Displays y Aplicaciones Fotonicas Department de Tecnologia Electronica Universidad Carlos III de MadridSpain IK4-CIDETEC Parque Tecnologico de San Sebastian GuipuzcoaSpain Indo optical Group Departamento I+D SantCugat del Valles BarcelonaSpain GIDFYS European University Miguel de Cervantes(UEMC)Department of HealthSciencesSpain

Purpose:To evaluate the potential clinical usability of a new prototype of ophthalmic blue light filters developed by using electrochromic technology in pseudophakic patients complaining of ***:A prototype of electrochromic device was developed,with a specific frame that enclosed an electronic driver that allowed personalizing its function for each patient.A pro-spective,observational case series study was performed to test *** patients who had un-dergone cataract surgery with clear intraocular lenses and complaining of glare were included in the *** outcome measures were the results obtained in the satisfaction questionnaire that was delivered to ***,visual acuity,contrast sensitivity,and reading ability data were evaluated with and without the prototype under diferent lighting conditions and different modes of the prototype after a complete month of *** transmittance was also ***:Visual acuity,contrast sensitivity and reading function did not change significantly with prototype *** main activity for which the prototype was used was *** one patient found that the dimming level was *** patients reported variable discomfort when passing tunnels,not sufficiently clear indoors,or put on and remove *** lenses slightly decreased their transmittance at the end of the ***:Glasses based on elect rochromic technology may be acceptable for outdoor/indoor use and for distance-near *** studies with larger samples must be conducted to confirm the clinical usability of these glasses.

关键词： optical filters electro-optical devices technical visual aids electronic control.

Novel approach for improving signal to noise ratio of seismic images

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Journal of Systems Engineering and Electronics 2004年第4期15卷 488-496页

作者： ChenFeng LiJinzong LiDongdong ImageInformationTechniqueandEngineeringGraduateSch~l HarbinInstituteofTechnologyHarbin150001P.R.China

A novel approach of digital image processing technology is applied to improve SNR of seismic images. At first, we analyze the characters of line-like texture in seismic images, and then a preprocessing method named 2 D tracing horizon filtering is designed. After that, the technology of optical flow analysis is adopted to calculate the displacement vectors of adjacent pixels between neighboring seismic images. At last, the novel image accumulation algorithms are proposed, which are applied to greatly improve SNR and definition of seismic images. The experimental results show that SNR of seismic section images with SNR of about 20 dB and 17 dB are increased 8 dB～9 dB under keeping signal energy 67%～80% by processing section images and 3dB～4dB under keeping signalenergy 80～90% by processing horizontal slice images. Thereby, the proposed novel approaches are very helpful to the correct seismic interpretation and have very important significance for seismic exploring.

关键词： Signal to noise ratio Filtering Image motion analysis Computer vision optical imaging optical filters

Performance analysis of all optical swapping networks with a label eraser made of a Gaussian filter

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Chinese Optics Letters 2003年第3期1卷 133-135页

作者：贾振生陈明华冯佳董毅谢世钟 Department of Electronic Engineerng Tsinghua University Beijng 100084

In this paper, a simple label eraser employing Gaussian apodized fiber Bragg grating (FBG) for all optical label swapping (AOLS) networks is proposed. Relying on the analysis of the payload through multi-stage erasers, this kind of eraser significantly improves the cascadability in comparison with the traditional fiber-loop mirror (FLM) eraser. The influences of the residual labels on the intermediate swapping node labels through the eraser are also investigated. It is shown that the power penalty is only less 1 dB when the optical power ratio of residual label to the new label signal arrives at -8 dB. The influence is negligible due to the sharp notch filtering effect of the Gaussian apodized FBG.

关键词： Fiber Bragg gratings optical communication optical filters

Tunable fiber ring laser employing a Sagnac interferometric filter

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Chinese Optics Letters 2005年第10期3卷 600-602页

作者：金晓峰周柯江 College of Information Science and Engineering Zhejiang University Hangzhou 310027

A tunable erbium-doped fiber ring laser employing an all-polarization-maintaining fiber loop filter is proposed and demonstrated. The lasing frequencies can be selected by properly adjusting the polarization controlle... 详细信息

关键词： Control equipment Erbium Fiber lasers Frequencies Interferometry optical filters Polarization Tuning

Stable single frequency Er-doped all-fiber ring laser with fiber Bragg grating Fabry-Perot filter

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Chinese Optics Letters 2005年第4期3卷 212-214页

作者：吕昌贵王元恽斌峰崔一平 Department of Electronic EngineeringSoutheast University Nanjing 210096

Using a fiber Bragg grating (FBG) and a Fabry-Perot cavity composed of two fiber Bragg gratings (FBGFP) as its frequency-selective components, a type of single frequency all-fiber ring laser permits oscillation only on one longitudinal mode of the main cavity without modehopping while the cavity length can be up to tens of meters. The salient feature is due to the single narrowband resonance of the FBGFP filter. Such a fiber ring laser is achieved experimentally, and the laser mode is limited inside the single resonance of the FBGFP.

关键词： Erbium Fiber Bragg gratings Frequencies Laser applications optical fiber coupling optical filters Rare earth additions Resonance Ring lasers Telecommunication