in this article, we suggested a novel design of polarization splitter based on coupler waveguide on inp substrate at 1.55mm wavelength. photonic crystal structure is consisted of two dimensional (2d) air holes embedded in inp/ingaasp material with an effective refractive index of 3.2634 which is arranged in a hexagonal lattice. the photonic band gap (pbg) of this structure is determined using t...

Infrared imagers are important for reorganization and monitoring. This paper discusses the design of an infrared imager. Optical design in medium wavelength infrared (MWIR) and long wavelength infrared (LWIR) bands is different and needs distinct detectors and materials. Reflective systems are not suitable due to their small field of view (FOV) and vignetting. Refractive dual band optical syste...

i ntroduction: liposuction using laser is now one of the most common cosmetic surgery. this new method has minimized the disadvantages of the conventional liposuction including blood loss, skin laxity and long recovery time. benefits of the new liposuction methods which include less trauma, bleeding and skin tightening prove the superiority of these methods over the traditional mechanical metho...

In this study, the effect of light wavelength on growth rate and lipid production of Synechocystis was investigated. Continuous cultivation system was used to have uniform cell density and avoid self-shading in order to obtain more precise results. Based on previous studies, red light is more efficient than other colors in the visible spectrum for cultivation of Synechocystis; however, the opti...

Bessel beams are of great interest due to their unique non-diffractive properties. Using a conical prism or an objective paired with an annular aperture are two typical approaches to generating zeroth order Bessel beams. However, the former approach has a limited numerical aperture (NA), and the latter suffers from low efficiency since most of the incident light is blocked by the aperture. Furt...

This paper describes an algorithm for optimally placing a given number of wavelength converters in all-optical networks with arbitrary topologies. We first introduce the simple network model upon which the algorithm is based. We provide a formulation of the overall network blocking probability when a given number of nodes in the network, is provided with full wavelength conversion capability. W...

In this paper, we study the following problem. Given the network topology and traffic demand, determine how a minimum set of wavelength converters should be placed to ensure that the number of wavelengths needed will not exceed a given bound L+u, where L is the maximum link load in the network and u is a parameter defined by the network designer to reflect the overall availability of wavelength...

Wavelength conversion has been shown as one of the key techniques to improve blocking performance in a wavelength-routed all-optical WDM network. Given that wavelength converters nowadays remain very expensive, how to make effective use of a limited number of wavelength converters becomes an important issue. In this paper, we present and analyze the Sparse-Partial Wavelength Conversion (SPWC) n...

Wavelength conversion has been shown as one of the key techniques that can improve the blocking performance in a wavelength-routed all-optical network. Given that wavelength converters nowadays are still very expensive, how to make effective use of the limited number of wavelength converters becomes an important issue. In this paper, we propose a novel sparse-partial wavelength conversion (SPWC...