We present an efficient ray-tracing technique to render bokeh effects produced by parametric aspheric lenses. Contrary to conventional spherical lenses, aspheric lenses do generally not permit a simple closed-form solution of ray-surface intersections. We propose a numerical root-finding approach, which uses tight proxy surfaces to ensure a good initialization and convergence behavior. Addition...

purpose: to compare aspheric and spherical hydrophilic intraocular lenses (iols) in terms of contrast sensitivity and visual acuity in photopic and mesopic conditions. methods: this triple-blind randomized clinical trial was performed on 40 eyes of 40 patients at al-zahra eye center, zahedan, iran. the eyes were randomized to standard phacoemulsification procedure with spherical (adapt, b&l;) o...

the aim of this study was to report a new cause of cataract, namely snake bite induced cataract in a dog. a 3-year-old male mongrel dog was referred to our clinic for the assessment of cataract in both eyes. the dog was bitten by a snake nearly 4 months ago. a 40 dioptre acrylic lens with 13 mm haptics was implanted into the lens capsule. in the left eye, posterior synechia was detected in the ...

purpose : cataract surgery is the most common ocular surgery worldwide and in modern era of phacoemulsification with posterior chamber intraocular lens (pc iol) implantation, refractive aspects of surgery is as important as the surgery itself. after the iol implantation, the anterior chamber depth (acd) is increased and the iridiocorneal angle is widened. these changes should be considered for ...

purpose: to evaluate the predictability, efficacy, and safety of iris-claw artisanô phakic intraocular lenses ­for myopia. methods: through a prospective clinical study, 35 eyes of 21 patients with myopia from -5 to 26.5 diopters underwent implantation of the artisan lens. patients were examined 1, 3, and 7 days (all eyes); 1 month (28 eyes), 3 months (29 eyes), and 6 months (32 eyes) after the...