Showing papers in "Optik in 2011"

TL;DR: In this paper, an ultra small size 4-channel wavelength division demultiplexer based on 2D photonic crystal modified Y-Branch, suitable for integration, is proposed.

TL;DR: In this article, X-ray diffraction analysis showed that the crystal structure of SnS thin films is orthorhombic with preferential orientation along 〈0.2.1.

TL;DR: The availability and the practical channel capacity's bounds are investigated, for links with fast and slow fading statistics, with line of sight architecture and intensity modulation with direct detection, through the evaluation of the outage probability and the outage and average capacity.

TL;DR: A robot tool center point (TCP) calibration approach is proposed to calibrate the relation between the laser 3-D scanner and the robot end-effector by using a criterion sphere to calibrates the pose of the turntable relative to the robot.

TL;DR: Fast Fourier transform (FFT) algorithm can be introduced into the calculation of convolution format of gyrator transform in the discrete case by using convolution operation.

TL;DR: A novel multi-image encryption and decryption algorithm based on Fourier transform and fractional Fourier transforms that has features of enhancement in decryption accuracy and high optical efficiency is presented.

TL;DR: In this paper, the spectral width of the source was analyzed and it was found that addition of spectral width in the source lowers the SBS effect, which could transmit more optical power in a single channel and maintain high OSNR.

TL;DR: In this article, the oblique propagation of electromagnetic waves in one-dimensional plasma dielectric photonic crystals, the superlattice structure consisting of alternating plasma and dielectrics materials using transfer matrix method, was considered.

TL;DR: In this paper, the anti-reflection coatings of solar cells have been fabricated using different techniques The techniques used include SiO2 thermal oxidation, ZnO/TiO2 sputtering deposition and porous silicon prepared by electrochemical etching Surface morphology and structural properties were investigated by using scanning electron microscopy and atomic forces microscopy Optical reflectance was obtained by using optical reflectometer I-V characterizations were studied under 80mW/cm2 illumination conditions.

TL;DR: In this article, an all optical switch based on nonlinear photonic crystal directional coupler has been simulated and analyzed by the finite difference time domain (FDTD) method, where the lunched pump signal increases the refractive indices of the central row of the coupler, due to nonlinear Kerr effect.

TL;DR: In this paper, a novel kind of large mode area photonic crystal fibers (PCFs) are proposed to achieve large effective mode area, and a novel technique is applied to seven missing air hole PCF structures.

TL;DR: In this paper, a highly birefringent index-guiding photonic crystal fibers with flattened dispersion and low effective area is proposed by introducing elliptical air holes in the cladding and small holes both in the core area and in cladding.

TL;DR: A new method for color-image encryption using Discrete Quaternion Fourier-Transforms combined with double random-phase encryption is reported, by which color images can be processed as single channel architecture, instead of as separated color components in three channels, so that the complexity of the encryption system can be effectively reduced without any reduction of its security.

TL;DR: In this paper, porous silicon (PS) surfaces were fabricated by electrochemical etching for both sides of the Si wafer to investigate the PS effect on performance of silicon solar cells.

TL;DR: In this paper, a laser interferometric system (LIS) based on oblique incidence and phase shifting technique has been designed for the measurement of gear tooth flank for a spur involute gear with a module of 2.0, 60 teeth and a 20-mm facewidth.

TL;DR: The proposed method that exploits the undecimated discrete fuzzy logic has much reduced noise sensitivity with respect to the linear unsharp masking technique and it permits to obtain perceptually pleasant results.

TL;DR: It is concluded that multiple access interference (MAI) is the dominant source of BER and there is graceful degradation in system performance when number of simultaneously active users increases.

TL;DR: In this article, the authors report on their current work to develop simple test equipment and optoelectronic models describing the performance and behaviours of dye-sensitised solar cells.

TL;DR: In this article, a highly non-linear hollow core photonic crystal fiber (PCF) having three ring-hexagonal structure is designed and the full vector finite element method with perfectly matched layer is used to investigate the nonlinear properties of hollow core PCF effectively.

TL;DR: In this paper, a semiorganic nonlinear optical crystal has been synthesized by growing single crystals by TSLC using slow evaporation solution growth technique at room temperature.

TL;DR: A blind watermarking scheme based on discrete fractional random transform that can be used in self-embedding for a large payload is provided and security of the watermark is preserved due to the randomness of the discrete fractionAL random transform.

TL;DR: In this paper, the maximum spectral dependence of EDFA gain with respect to temperature is obtained for single stage (SS), double-stage (DS), and gain flattened (GF) DS L-band erbium-doped fiber amplifier (EDFA) configurations.

TL;DR: By discussing with the different output function of SVM, it is confirmed that the model meets the requirements of end-point judgment online and can measure the content of carbon in the molten iron in real time by using this model.

TL;DR: In this paper, a microscopic TV holographic arrangement is described to study the static and vibrating microsystems, where the object beam and the reference beam arms are provided with a phase shifting mirror and a bias phase modulation mirror to carry out the measurement of the out-ofplane deformation and the vibration amplitude fields, respectively.

TL;DR: In this article, the authors present the modeling and characterization of an optical fiber grating for maximum reflectivity, which is based on solving coupled mode equations by transfer matrix method that describes the interaction of guided modes.

TL;DR: In this paper, the interaction of three laser fields with a four-level quantum system in a tripod configuration was analyzed and an analytical expression for the linear susceptibility and nonlinear susceptibility of a weak-probe field was obtained.

TL;DR: In this article, the authors solved the reduced Lagrangian problem for beam width and curvature, assuming a trial Gaussian profile, and two scale lengths for inhomogenity along the direction of propagation, one for nonlinearity and other for diffraction management are introduced.

TL;DR: In this paper, a surface plasmon resonance (SPR) sensor based on diffraction grating with high sensitivity and high resolution is proposed, and 3-nm-thick gold film is deposited on the grating surface in order to protect the Al layer from getting oxidized.

TL;DR: In this article, a novel frequency encoded all optical half adder, half subtractor, and full adder is proposed and the implementation is ultrafast one and the frequency encoding makes it intensity loss dependent problem free.

TL;DR: An efficient wavelength assignment algorithm for dynamic provisioning of lightpath based on most-used wavelength assignment algorithms and a mathematical model for WDM optical networks for minimization of blocking probability are proposed.