نتایج جستجو برای: optical coherent transient

تعداد نتایج: 441505  

Mohammad R. N. Avanaki Mohammad R. Pishgoo Reza Ebrahimpour

Optical Coherence Tomography (OCT) uses the spatial and temporal coherence properties of optical waves backscattered from a tissue sample to form an image. An inherent characteristic of coherent imaging is the presence of speckle noise. In this study we use a new ensemble framework which is a combination of several Multi-Layer Perceptron (MLP) neural networks to denoise OCT images. The noise is...

Journal: :Optics express 2009
Nicolas K Fontaine Ryan P Scott Jonathan P Heritage S J B Yoo

Four-quadrature spectral interferometry using balanced coherent detection enables single-shot full-field characterization of complex-shaped optical waveforms with near quantum-limited sensitivity. A 90 degrees optical hybrid places a waveform in four-quadrature-phases with a stronger, well-characterized reference pulse. Measurement of the four spectra with an integrating two-dimensional detecto...

2015
Junwen Zhang Jianjun Yu Nan Chi

All optical method is considered as a promising technique for high symbol rate Nyquist signal generation, which has attracted a lot of research interests for high spectral-efficiency and high-capacity optical communication system. In this paper, we extend our previous work and report the fully experimental demonstration of polarization-division multiplexed (PDM) all-optical Nyquist signal gener...

1996
A. van den Bos A. J. den Dekker

Earlier results on parametric model-based optical resolution by the first author [J. Opt. Soc. Am. A 4, 1402 (1987)] concerned two incoherent sources of known intensity. These results are generalized to sources with any degree of coherence and unknown intensity. A further generalization is that the model underlying the observations and that chosen by the experimenter need not be the same. It is...

Journal: :CoRR 2011
Fanggang Wang Xiaodong Wang

We consider application of the discrete Fourier transform-spread orthogonal frequency-division multiplexing (DFT-spread OFDM) technique to high-speed fiber optic communications. The DFT-spread OFDM is a form of single-carrier technique that possesses almost all advantages of the multicarrier OFDM technique (such as high spectral efficiency, flexible bandwidth allocation, low sampling rate and l...

2012
A. M. Jorgensen H. R. Schmitt G. T. van Belle D. Hutter J. T. Armstrong E. K. Baines S. Restaino T. Hall Jayadev K. Rajagopal Fabien Malbet

Optical Interferometry has long been limited by low SNR making it nearly impossible to measure the small visibilities required to make resolved images. Although the SNR exists in the raw data, much SNR is lost in the conventional squared-visibility processing. In modern interferometers fringes are recorded simultaneously at many wavelengths and baselines. This makes phase-referencing possible, ...

Journal: :Physical review letters 2000
Dekorsy Bartels Kurz Kohler Hey Ploog

We investigate coherent Bloch oscillations in GaAs/AlxGa1-xAs superlattices with electronic miniband widths larger than the optical phonon energy. In these superlattices the Bloch frequency can be tuned into resonance with the optical phonon. Close to resonance a direct coupling of Bloch oscillations to LO phonons is observed which gives rise to the coherent excitation of LO phonons. The densit...

The possibility of inserting an optical klystron on the storage ring of an Iranian Light Source Facility as a Synchrotron Radiation Free electron Laser for coherence harmonic generation in the soft x-ray spectrum has been studied. The study has been performed using the 3D FEL simulation code GENESIS 1.3 and in accordance with the available characteristic parameters of ISLF. Different potential ...

پایان نامه :دانشگاه تربیت معلم - تهران - دانشکده علوم 1393

in this thesis, structural, electronical, and optical properties of inverse pervskite(ca3pbo) in cubic phase have been investigated.the calculation have been done based on density functional theory and according to generalized gradiant approximate (gga) as correlating potential. in order to calculate the configurations, implementing in the wien2k code have been used from 2013 version. first of ...

Journal: :Optics letters 1995
P R Hemmer D P Katz J Donoghue M Cronin-Golomb M S Shahriar P Kumar

We have observed optical phase-conjugate gain (.50) in sodium vapor, using low-intensity pump lasers (1 Wycm2), with a response time of the order of 1 ms. Coherent population trapping is experimentally identified as the phase-conjugate mechanism. A theoretical model is presented that supports these observations by showing that coherent population trapping can write large-amplitude nonlinear-opt...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید