A population study on changes in wave aberrations with accommodation

Abstract

Wave aberrations were measured with a Shack-Hartmann wavefront sensor (SHWS) in the right eye of a large young adult population when accommodative demands of 0, 3, and 6 D were presented to the tested eye through a Badal system. Three SHWS images were recorded at each accommodative demand and wave aberrations were computed over a 5-mm pupil (through 6th order Zernike polynomials). The accommodative response was calculated from the Zernike defocus over the central 3-mm diameter zone. Among all individual Zernike terms, spherical aberration showed the greatest change with accommodation. The change of spherical aberration was always negative, and was proportional to the change in accommodative response. Coma and astigmatism also changed with accommodation, but the direction of the change was variable. Despite the large inter-subject variability, the population average of the root mean square for all aberrations (excluding defocus) remained constant for accommodative levels up to 3.0 D. Even though aberrations change with accommodation, the magnitude of the aberration change remains less than the magnitude of the uncorrected aberrations, even at high accommodative levels. Therefore, a typical eye will benefit over the entire accommodative range (0-6 D) if aberrations are corrected for distance viewing.

The influence of eye movements on monochromatic wavefront aberrations

“…Über 90 % der Aberrationen korrespondieren allein mit der zweiten Ordnung (Castejón-Mochón et al 2002, Guirao et al 2002, Thibos et al 2002b, Cheng et al 2004a). …”

“…Die sphärische Aberration zeigt im akkommodierten Auge einen eindeutigen Trend zu negativen Werten (He et al 2000, Artal et al 2002a, Ninomiya et al 2002, Cheng et al 2004a, Plainis et al 2005 Die Zernike-Koeffizienten höherer Ordnung bleiben bei Akkommodation annähernd gleich (Ninomiya et al 2002, He et al 2003, Cheng et al 2004a Dorronsoro et al 2003, Joslin et al 2003, Dietze und Cox 2004.…”

A method for enhancing digital information displayed to computer users with visual refractive errors via spatial and spectral processing

“…Current technology to characterize the optics in the human eye does so under certain viewing conditions, namely a relaxed accommodative state. Any divergence in viewing conditions from those used to characterize the eye will change the characterization [7,12]. For example, the eyes of a person viewing a liquid crystal display (LCD) panel will not be in a relaxed state due the fact that he/she must accommodate for viewing the LCD panel at a finite distance.…”

“…PC-B '255 (3)(4)(5)(6)(7)(8)(9) where OPC-D is the "shifted and scaled" precompensated object. shows the result of simulating the retinal projection of the precompensated object.…”

“…[17] A e B = z[(B)r n A]c Al (3)(4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18)(19) A graphical summary of the image segmentation portion of the algorithm is shown in Figure 3-14. The final result of the image segmentation process is shown in Figure 3-14e.…”