A theoretical analysis of a fiber optical photonic band gap based tunable wavelength filter is presented. The design presented here is based on the quarter wave reflector with a liquid crystal defect layer in the middle of the structure. The filter generated by the structure is shifted in wavelength as the voltage applied to the structure is modified. Some critical parameters are analyzed: the ...

PURPOSE To improve our understanding of hyperacuity defects measured with preferential hyperacuity perimetry (PHP) by correlating PHP findings with the retinal microstructural changes visible on spectral-domain optical coherence tomography (OCT) in patients with polypoidal choroidal vasculopathy (PCV). MATERIALS AND METHODS Twenty-eight eyes of 28 patients with PCV were retrospectively review...

background: congenital heart disease (chd) is the most common congenital anomaly in newborns. this study was performed to determine the live birth incidence of chd by ethnicity and sex in gorgan, northern iran. methods: in this longitudinal, hospital-based study, 18162 live births in dezyani hospital in gorgan, north of iran, were screened for chd, from 2007 through 2009. clinical examination, ...

An inhomogeneous layer is sandwiched between homogeneous half-spaces. The layer contains a defect. There are incident waves and the problem is to calculate the scattered waves. Five recent publications are criticised, mainly because of their misuse of the method of images. 2011 Elsevier Ltd. All rights reserved.

The defect structure in relaxed (100) InGaAs/GaAs heteroepitaxial systems grown by molecular beam epitaxy is studied by selective electrochemical (anodic) etching. By incremental layer removal, we map the depth profile of the dislocation density. The density of dislocations is inversely proportional to the layer thickness and increases with misfit. The results are compared to theoretical models.