Results 321 to 330 of about 415,852 (378)

Spectral bandwidth and ocular accommodation

Journal of the Optical Society of America A, 1995
Previous studies have suggested that targets illuminated by monochromatic (narrow-band) light are less effective in stimulating the eye to change its focus than are black-white (broadband) targets. The present study investigates the influence of target spectral bandwidth on the dynamic accommodation response in eight subjects. The fixation target was a
Karan R. Aggarwala, Steven Mathews, Ekaterina S. Kruger, Philip B. Kruger   +3 more
openaire   +3 more sources

The Effect of Accommodation on Ocular Shape

Optometry and Vision Science, 2002
Ocular shape is altered in myopia, and accommodation during nearwork is a proposed risk factor for myopia. Using relative peripheral refractive error (RPRE), ocular shape was assessed before, during, and after a period of sustained nearwork to determine whether accommodation affects ocular shape.Measurements of RPRE at 30 degrees in the nasal visual ...
Terry W Walker, Donald O. Mutti
openaire   +3 more sources

Role of ocular aberrations in dynamic accommodation control [PDF]

Clinical and Experimental Optometry, 2009
Accommodation control is mediated by a number of cues, including blur,chromatic aberration and target proximity. Data from wavefront measurements have shown clear shifts in ocular aberrations during increasing accommodative demand, most notably a negative shift in spherical aberration. Work in adaptive optics, where aberrations have been corrected, has
Chin, Sem Sem, Hampson, Karen, Mallen, Edward A.H.   +2 more
openaire   +2 more sources

Effect of migraine attack on pupil size, accommodation and ocular aberrations

European Journal of Ophthalmology, 2020
Purpose: To evaluate the pupil size, accommodation, and ocular higher-order aberrations (HOAs) in patients with migraine during migraine attacks and compare them with interictal period and healthy controls.
M. B. Yıldız, E. Yildiz, Sevcan Balci, Buse Rahime Hasırcı Bayır, Y. Çetinkaya   +4 more
semanticscholar   +1 more source

Changes in ocular dimensions and refraction with accommodation

Ophthalmic and Physiological Optics, 1997
The purpose of this study was to measure the changes in ocular dimensions with accommodation, with particular reference to the radius of curvature of the posterior surface of the crystalline lens. The increase in power of the eye with accommodation is considered to arise primarily from a decrease in the radius of curvature of the anterior surface of ...
Leon F. Garner, Maurice Yap
openaire   +3 more sources

Effect of accommodation of the lens on ocular pressure

Irish Journal of Medical Science, 1995
In a randomised single blind trial, eye pressures were significantly (p < 0.01) lower in a group (n=33) of subjects who read for 15 minutes than in a control group (n=33).
J Stokes, Patricia Fitzpatrick, J. Blake, P Carroll, T Horgan   +4 more
openaire   +3 more sources

Effect of correction of aberration dynamics on chaos in human ocular accommodation.

Optics Letters, 2013
We used adaptive optics to determine the effect of monochromatic aberration dynamics on the level of chaos in the accommodation control system. Four participants viewed a stationary target while the dynamics of their aberrations were either left ...
K. Hampson, Matthew P. Cufflin, E. Mallen   +2 more
semanticscholar   +1 more source

Status of Residual Refractive Error, Ocular Aberrations, and Accommodation After Myopic LASIK, SMILE, and TransPRK.

Journal of refractive surgery, 2019
PURPOSE To analyze residual refractive error, ocular aberrations, and visual acuity (VA) during accommodation simultaneously with ocular aberrometry in eyes after laser-assisted in situ keratomileusis (LASIK), small incision lenticule extraction (SMILE),
Naren Shetty, Zelda Dadachanji, Raghav Narasimhan, Gairik Kundu, P. Khamar, P. Ahuja, Vijaya Kumar, Vikas Kumar, R. Shetty, R. Nuijts, Abhijit Sinha Roy   +10 more
semanticscholar   +1 more source

A Biometric Study of Ocular Changes During Accommodation

American Journal of Ophthalmology, 1993
We performed a biometric study that used A-mode ultrasonography on 106 subjects during ocular accommodation. The subjects were divided into two groups; group 1 included 76 subjects and group 2 included 30 subjects. In group 1, we measured the anterior chamber depth, lens thickness, and axial length in the right eye while the left eye, wearing ...
Patrick Joi-Tsang Shum, Chak-Lau Ng, Liang-Shi Ko, Shun-Ling Lin   +3 more
openaire   +5 more sources

Ocular accommodation in chickens: Corneal vs lenticular accommodation and effect of age

Vision Research, 1986
The avian accommodative response has long been suspected of having a corneal component resulting from contraction of a limbal extension of the ciliary muscle. Efforts to confirm the existence of such a mechanism have been sporadic and the results contradictory.
Jacob G. Sivak, L.A. Ryall, C.G. Lebert, L.M. Myshak, T.E. Hildebrand   +4 more
openaire   +3 more sources