purpose : to evaluate the near visual performance of an accommodative intraocular lens (iol) tetraflex, in comparison to a standard monofocal foldable iol in cataract surgery. setting: eye research center , farabi eye hospital , department of ophthalmology, tehran university of medical sciences, iran . methods : forty six eyes of 23 patients with cataract underwent phacoemulsification and accom...

Robot force control implemented by means of passive mechanical devices has inherent advantages over active implementations with regard to stability, response rapidity, and physical robustness. The class of devices considered in this paper consists of a Stewart platform-type mechanism interconnected with a network of adjustable mechanical elements such as springs and dampers. The control law rep...

PURPOSE To document zonular orientation and suspension of the lens during accommodation, and age-related changes of the circumlental space (CLS) at rest and during accommodation, in living iridectomized rhesus monkey eyes. METHODS The CLS was measured in 34 iridectomized eyes of 24 living rhesus monkeys, age 5.7 to 26 years, in the resting and accommodated state, and the orientation of the zo...

Ocular accommodation provides a well-focussed image, feedback for accurate eye movement control, and cues for depth perception. To accurately perform visually guided motor tasks, integration of ocular motor systems is essential. Children with motor coordination impairment are established to be at higher risk of accommodation anomalies. The aim of the present study was to examine the relationshi...

PURPOSE To estimate changes in surface shape and gradient refractive index (GRIN) profile in primate lenses as a function of accommodation. To quantify the contribution of surface shape and GRIN to spherical aberration changes with accommodation. METHODS Crystalline lenses from 15 cynomolgus monkeys were studied in vitro under different levels of accommodation produced by a stretching system....

PURPOSE We tested the hypothesis that changes in accommodation after instillation of Phenylephrine Hydrochloride (PHCl) observed in some studies could be caused by changes in optics. METHODS We performed two experiments to test the effects of PHCl on static and on dynamic accommodation in 8 and 6 subjects, respectively. Objective wavefront measurements were recorded of the static accommodatio...

OBJECTIVE Disparity cues can be a major drive to accommodation via the convergence accommodation to convergence (CA/C) linkage, but, on decompensation of exotropia, disparity cues are extinguished by suppression so this drive is lost. This study investigated accommodation and vergence responses to disparity, blur and proximal cues in a group of distance exotropes aged between 4 and 11 years bot...

Takashi Shibata Takashi Kawai Keiji Ohta Masaki Otsuki Nobuyuki Miyake Yoshihiro Yoshihara Tsuneto Iwasaki Abstract — This paper describes a method for reducing the discrepancy between accommodation and convergence when viewing stereoscopic 3-D images. The method uses a newly developed stereoscopic 3-D display system with a telecentric optical system and a mobile LCD. The examination of a mono-...

PURPOSE An association between tonic accommodation, the resting accommodative position of the eye in the absence of a visually compelling stimulus, and refractive error has been reported in adults and children. In general, myopes have the lowest (or least myopic) levels of tonic accommodation. The purpose in assessing tonic accommodation was to evaluate it as a predictor of onset of myopia. M...

Robot force control implemented by means of passive mechanical devices has inherent advantages over active implementations with regard to stability, response rapidity, and physical robustness. The class of devices considered in this paper consists of a Stewart platform-type mechanism interconnected with a network of adjustable mechanical elements such as springs and dampers. The control law rep...