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Technique of active phase stabilization for the interferometer with 128 actively selectable paths [article]

Yu Xu, Jin Lin, Yu-Huai Li, Hui Dai, Sheng-Kai Liao, Cheng-Zhi Peng
2018 arXiv   pre-print
the DAC, maintaining a high visibility of the interferometer every time a new light path is selected.  ...  By monitoring photon counting rates of two Up-Conversion Detectors (UCD) at two output ports of the interferometer, a Field Programmable Gate Array (FPGA) calculates and finds the optimal code value for  ...  Stabilization preparation Stage In order to realize real-time phase stabilization, Bob's control system is designed to refresh the optimal data for phase stabilization in first 340 ms of every second,  ... 
arXiv:1806.03678v1 fatcat:d3isuohlajf5fcq2l5d3n55fgu

Demo

Zeyu Wang, Zhice Yang, Jiansong Zhang, Chenyu Huang, Qian Zhang
2015 Proceedings of the 13th Annual International Conference on Mobile Systems, Applications, and Services - MobiSys '15  
Visible Light Positioning (VLP) provides a promising means to achieve indoor localization with sub-meter accuracy.  ...  We observe that the Visible Light Communication (VLC) methods in existing VLP systems rely on intensity-based modulation, and thus they require a high pulse rate to prevent flickering.  ...  We are grateful to Su Pan for helping us with LCD and Hang Wu for helping us with the deployment on Google Glass.  ... 
doi:10.1145/2742647.2745924 dblp:conf/mobisys/WangYZHZ15a fatcat:3het3wtezzdphpvedonvor7sga

Non-line-of-sight imaging over 1.43 km

Cheng Wu, Jianjiang Liu, Xin Huang, Zheng-Ping Li, Chao Yu, Jun-Tian Ye, Jun Zhang, Qiang Zhang, Xiankang Dou, Vivek K Goyal, Feihu Xu, Jian-Wei Pan
2021 Proceedings of the National Academy of Sciences of the United States of America  
In hardware, we develop a high-efficiency, low-noise NLOS imaging system at near-infrared wavelength based on a dual-telescope confocal optical design.  ...  Whereas conventional imaging involves direct line-of-sight light transport to recover the visible objects, NLOS imaging aims to reconstruct the hidden objects from the indirect light paths that scatter  ...  For hardware, we mainly discuss the optimized system design and some calibrations; for software, we include a more detailed forward model and some simulation results.  ... 
doi:10.1073/pnas.2024468118 pmid:33658383 fatcat:e7z6xgapgzfd5isdojxi3zponm

Temporal synchronization of GHz repetition rate electron and laser pulses for the optimization of a compact inverse-Compton scattering x-ray source

M.R. Hadmack, E.B. Szarmes, J.M.J. Madey, J.M.D. Kowalczyk
2015 Nuclear Instruments and Methods in Physics Research Section A : Accelerators, Spectrometers, Detectors and Associated Equipment  
The arrival times of electron and laser pulses must be synchronized with picosecond precision.  ...  We have developed an RF synchronization technique that reduces the initial timing uncertainty from 350 ps to less than 2 ps, greatly reducing the parameter space to be optimized while commissioning the  ...  The RF amplitude and phase compensation system 5 was used to record the complex waveforms of the 2.856 GHz component of the photodiode signal for the OTR light as well as the CHR light for six different  ... 
doi:10.1016/j.nima.2014.10.074 fatcat:f2r37sv5pvbrdmp5ywrlvamaha

Broadband Sum Frequency Generation with Two Regenerative Amplifiers: Temporal Overlap of Femtosecond and Picosecond Light Pulses

E. L. HOMMEL, H. C. ALLEN
2001 Analytical Sciences  
In the BBSFG system design presented here, the fs pulse and the ps pulse that are generated in separate regenerative amplifiers are overlapped temporally. This temporal overlap process is discussed.  ...  The new approach in experimental design described here for this emerging technology, BBSFG, has application for studying time-dependent processes at interfaces that inherently produce low SFG signal levels  ...  We are also indebted to Bill White from Positive Light for his insightful comments. In addition, the Ohio State University Seed Grant is acknowledged.  ... 
doi:10.2116/analsci.17.137 pmid:11993650 fatcat:2rdodfaiovfdzhmu4yiyywa3a4

Nonlinear restoration of pulse and high noisy images via stochastic resonance

Qibing Sun, Hongjun Liu, Nan Huang, Zhaolu Wang, Jing Han, Shaopeng Li
2015 Scientific Reports  
The visibility and quality of output images can be improved by appropriately adjusting the system parameters.  ...  As opposed to previously reported designs, this unique approach employs a continuous noise and pulse signal for the generation of modulation instability.  ...  The nanosecond noise-hidden images grow at the expense of noise and become visible by optimizing the system parameters.  ... 
doi:10.1038/srep16183 pmid:26530885 pmcid:PMC4632024 fatcat:ddrmbwzgq5eubdbxfe3vcasnzy

Selective retina therapy: toward an optically controlled automatic dosing

Eric Seifert, Jan Tode, Amelie Pielen, Dirk Theisen-Kunde, Carsten Framme, Johann Roider, Yoko Miura, Reginald Birngruber, Ralf Brinkmann
2018 Journal of Biomedical Optics  
Fifteen laser pulses with stepwise increasing pulse energy were applied per treatment spot. Overall, 4626 pulses were used for algorithm parameter optimization and testing.  ...  Pulse energy thresholds for selective RPE effects vary intra-and interindividually.  ...  (Republic of Korea) for resourcing the R:GEN Laser Systems including the hardware for detection of backscattered light and the according raw data.  ... 
doi:10.1117/1.jbo.23.11.115002 fatcat:kvdu6zogkfakrkbruuu6jvh3ma

Head mounted DMD based projection system for natural and prosthetic visual stimulation in freely moving rats

Tamar Arens-Arad, Nairouz Farah, Shai Ben-Yaish, Alex Zlotnik, Zeev Zalevsky, Yossi Mandel
2016 Scientific Reports  
The system is based on a customized miniature Digital Mirror Device (DMD) for pattern projection, in both visible (525 nm) and NIR (915 nm) wavelengths, and a lens periscope for relaying the pattern directly  ...  Many of these emerging technologies are based on the projection of high intensity light patterns at specific wavelengths, raising the need for the development of specialized projection systems.  ...  Yuval Kapellner for his contribution to the design and construction of the projection system. We would also like to thank Mr.  ... 
doi:10.1038/srep34873 pmid:27731346 pmcid:PMC5059752 fatcat:3cefbbbitvg2bo3phb46dmej5y

Sub-20 fs visible pulses with 750 nJ energy from a 100 kHz noncollinear optical parametric amplifier

J. Piel, E. Riedle, L. Gundlach, R. Ernstorfer, R. Eichberger
2006 Optics Letters  
The design of the single-stage amplifier has been carefully optimized, and the design considerations are discussed.  ...  The device delivers sub-20 fs pulses tunable from 460 nm to beyond 1 m and pulse energies up to 750 nJ when it is pumped with 7 J of energy.  ...  The authors thank Frank Willig for continuous support of the project. Financial support from the Deutsche Forschungsgemeinschaft is gratefully acknowledged. E.  ... 
doi:10.1364/ol.31.001289 pmid:16642088 fatcat:55iceaaambeglepuspacc2wzru

Spectral Hump Formation in Visible Region of Supercontinuum from Shaped Femtosecond Laser Filamentation in Fused Silica

Junwei Chang, Dongwei Li, Tingting Xi, Lanzhi Zhang, Zuoqiang Hao
2021 Photonics  
We investigate experimentally the local intensity control in the visible region of the supercontinuum (SC) generated from femtosecond laser filamentation in fused silica by using pulse shaping technology  ...  The pulse shaper design is similar to the report by Weiner [36] , which consists of a 4f zero-dispersion pulse compressor and a 792 × 600 element pixel liquid crystal spatial light modulator (SLM, X10468  ...  The pulse shaper design is similar to the report by Weiner [36] , which consists of a 4f zero-dispersion pulse compressor and a 792 × 600 element pixel liquid crystal spatial light modulator (SLM, X10468  ... 
doi:10.3390/photonics8080339 fatcat:b4ufaimcnve5lj6kwgdtprtp5i

Optimization of duty cycles for LED based indoor positioning system

Olaoluwa R. Popoola, Wasiu O. Popoola, Roberto Ramirez-Iniguez, Sinan Sinanovic
2016 2016 International Conference for Students on Applied Engineering (ISCAE)  
In this paper, an optimal duty cycle, which increases packet delivery ratio (PDR) and reduces probability of collision is designed for packet transmission in an indoor positioning system based on a multiple  ...  MLEM improves positioning accuracy by identifying positions of overlap regions where light footprints from multiple LEDs.  ...  ACKNOWLEDGMENT The authors would like to appreciate the support for this research work from the School of Engineering and Built Environment of Glasgow Caledonian University through the University sponsored  ... 
doi:10.1109/icsae.2016.7810219 fatcat:67n22g5orzaa5js4d6oswhov7m

Performance Optimization of Visible Light Communication

Agha Yasir Ali, Electronics Engineering Dept, Sir Syed University of Engineering and Technology karachi, 78300, Pakistan, Lubna Farhi, Usama Ahmed, Asad Subhan, Hussain Safdar, Syeda Shaherbano Zaidi, Electronics Engineering Dept, Sir Syed University of Engineering and Technology karachi, 78300, Pakistan, Electronics Engineering Dept, Sir Syed University of Engineering and Technology karachi, 78300, Pakistan, Electronics Engineering Dept, Sir Syed University of Engineering and Technology karachi, 78300, Pakistan, Electronics Engineering Dept, Sir Syed University of Engineering and Technology karachi, 78300, Pakistan, Electronics Engineering Dept, Sir Syed University of Engineering and Technology karachi, 78300, Pakistan
2021 Maǧallaẗ al-abḥāṯ al-handasiyyaẗ  
This paper focuses to analyze the data rate, bit error rate (BER), flickering & bandwidth of visible light communication (VLC) system.  ...  All performance parameters are evaluated on Arduino based hardware VLC system. We conclude that the BER performance deteriorates by improving flickering performance and data rate of the VLC system.  ...  INTRODUCTION Visible Light Communication (VLC) systems takes advantage of light emitting diodes (LEDs) which can be pulsed at very high speeds without noticeable effect on the lighting output and human  ... 
doi:10.36909/jer.11397 fatcat:v2p32ndwynhm3cnjbtnd2me2a4

Real-time characterization and optimal phase control of tunable visible pulses with a flexible compressor

P. Baum, S. Lochbrunner, L. Gallmann, G. Steinmeyer, U. Keller, E. Riedle
2002 Applied physics B  
The SPIDER setup has been optimized for online diagnosis of tunable visible pulses with a 1 kHz repetition rate and 10-40 fs duration.  ...  With an evolutionary strategy guided by the spectral phase information of the SPIDER, optimal compression of the NOPA pulses to a 7.6 fs duration is achieved.  ...  ACKNOWLEDGEMENTS We thank Johannes Piel for important technical assistance and Clark-MXR Europa/Jobin Yvon GmbH for the generous loan of the CPA-2001 femtosecond amplifier used in the experiments and for  ... 
doi:10.1007/s00340-002-0909-5 fatcat:uqmtwqlxkredtegejapm6xyism

A VLC-based beacon location system for mobile applications

Guillermo del Campo-Jimenez, Jorge M. Perandones, F. J. Lopez-Hernandez
2013 2013 International Conference on Localization and GNSS (ICL-GNSS)  
This paper proposes a low cost and complexity indoor location and navigation system using visible light communications and a mobile device.  ...  Experimental designs for transmitter and receiver interfaces are presented and potential applications are discussed.  ...  VLC (Visible Light Communications) exploits the relative high switching speed of LEDs to use the light from SSL not only for lighting but also as a transmission channel.  ... 
doi:10.1109/icl-gnss.2013.6577276 dblp:conf/icl-gnss/Campo-JimenezPL13 fatcat:hckoqgj3wjg47cr5dhzrkp3mbq

Free-space confocal magneto-optical spectroscopies at milliKelvin temperatures [article]

B.J. Lawrie, M. Feldman, C.E. Marvinney, Y.Y. Pai
2021 arXiv   pre-print
Four are optimized for broadband visible single photon detection.  ...  sample positioning but not for imaging.  ... 
arXiv:2103.06851v1 fatcat:jgaccvxnmzctrknnidvcaqmbta
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