purpose: to determine the prevalence of ocular manifestations in marfan’s syndrome. methods: this cross-sectional study was performed on 43 patients referred to ophthalmology clinics of yazd medical university over 27 months. common ocular manifestations of marfan’s syndrome including lens dislocation, corneal disorders, retinal conditions, glaucoma were evaluated. results: the study included 2...

It has recently been noted by Park & Gott (1997) that there is a statistically significant negative correlation between gravitational lens image separations and source redshifts. This negative correlation is puzzling since is cannot be explained with any realistic models both in flat and open cosmologies, while ususal lens statistics, such as number density and distribution of image separation,...

Negative refraction and left-handed electromagnetism in a photonic crystal are demonstrated in waveguide and free space experiments at microwave frequencies. Precision control to achieve tailor-made refractive indices has been achieved. The negative refraction in these photonic crystals is shown to lead to imaging by a flat lens. We have also developed a generalized theory of flat lens imaging....

In 1968, Veselago predicted that a thin film composed of a material with a negative refractive index would act as a flat lens [Sov. Phys. Usp. 10, 509 (1968)]. Hyperbolic metamaterials have been designed that show negative refraction, but the condition of an isotropic refractive index n −1 required to realize a diffraction-limited focus cannot be realized using the hyperbolic dispersion. Here, ...

OBJECTIVES To investigate the influence of full scleral lenses on corneal curvature and pachymetry in keratoconus patients. METHODS In this intervention study, 20 eyes of 14 patients were measured by Scheimpflug imaging (Pentacam HR, Oculus) at two time points: directly and ≥1 week after scleral lens removal. Steep, flat and maximal keratometry (K(steep), K(flat) and K(max)) and optical pachy...

The effects of using a wind acceleration device (wind lens) with vertical-axis wind turbines in wind tunnel experiments were examined. A wind lens consists of a diffuser and flanges, and this study investigated the optimum parameters of their configuration with regard to the power augmentation of the turbines. The wind lens with a flat-panel-type diffuser demonstrated power augmentation by a fa...