Method of locating the visual axis objectively

Abstract

The proposed technique can be incorporated into any clinical wavefront sensing instrument and can be used for centration-sensitive vision correction, as well as for other instances when knowing the exact position of the fovea is important.

Nick-named laser radars

“…Comparing the refraction error maps for different aspects (angles α 1 , α 2 , α 3 , α 4 , α 5 between the visual axis of the eye and the optical axis of the instrument), it is evident that correcting the aberrations measured with incorrect positioning of the aberrometer, no satisfactory results would be achieved since the residual aberrations can be even higher than those measured with correct positioning. Objective determination of the visual axis was recently proposed [39]. It is based on the analysis of foveola profile and determination of its center using a two-beam configuration with beam scanning along a circular trajectory and measuring the phase relations in the received signals.…”

Visual and Physiological Optics: where will the journey lead us in 10 years?

“…In myopic subjects these objective refractions led to visual acuities that were equivalent to those obtained by subjective refractions, but the subjects tended to prefer the objective refraction. Another contribution, by Molebny, considered a new way to objectively determine the visual axis of the eye using scanning laser beams and nanometre scale sensitivity. This method may be implemented in commercial aberrometers to improve the alignment of wavefront measurements.…”