The spatial modulation of the Fermi velocity for gapless Dirac electrons in quantum materials is mathematically equivalent to problem massless fermions on a certain class curved spacetime manifolds. We study null geodesic lensing through these manifolds, which are dominated by curvature singularities, such as nematic singularity walls (where cone flattens along one direction). Null geodesics le...

Objective- Assessment of the lens anterior – posterior (AP) diameter as compared with the eye globe by ultrasonography in rabbit.   Design- Descriptive study.   Animals- 120 male and female rabbits, two months to four years old, and weighting between 300 to 1500gr.   Procedures- 2D ultrasonography of the eyes was performed and AP diameter of the eyes and lens were measured using Sonosite Tit...

A mathematical model describing the behavior of low-resolution Fresnel encoded lenses (LRFEL's) encoded in any low-resolution device (e.g., a spatial light modulator) has recently been developed. From this model, an LRFEL with a short focal length was optimized by our imposing the maximum intensity of light onto the optical axis. With this model, analytical expressions for the light-amplitude d...

Motion blur and defocus blur are two common visual effects for rendering realistic camera images. This paper presents a novel clip space culling for stochastic rasterization to render motion and defocus blur effects. Our proposed algorithm reduces the sample coverage using the clip space information in camera lens domain (UV) and time domain (T). First, samples outside the camera lens were cull...

purpose: to determine the effect of using rigid gas permeable (rgp) contact lenses in improvement of involuntary eye movements and visual functions in hyperopic astigmatism patients with congenital nystagmus. methods: this prospective interventional case series study was conducted on patients with congenital nystagmus and hyperopia equal or more than +0.5 d and astigmatism more than -1 d, who w...