
	Schema of a "wavefront"

Aberrometer / Wavefront Technology

The Aberrometer is an instrument which measures the total refractive error of the optical system of the eye.

A wave of parallel rays of light is sent into the eye and focused on the retina.

Upon exiting the eye, the reflected light ray is sent through an array of lenses and recorded with a very small camera.

An eye with ideal vision will reflect the rays of light in a straight wave front left, below). Each deviation of the straight wave represents one diopter, or unit of refraction (right, below).

After measuring the total refractive error it can then be accurately corrected with laser surgery. From the deviations in intensity of the light projected through the array of lenses and from its enlargement, reduction and distortion effects, the Aberrometer determines spherical and cylindrical refractive errors as well as the so-called "higher order aberrations", which have an effect on the quality of optical imaging. These deviations of flat light waves are translated into an ablation profile for the laser, which optimizes the refractive correction of the cornea.

Based on this “wavefront” technology, the Aberrometer-guided LASIK attempts to correct the exact refractive error of the eye. This is contrasted with traditional LASIK surgery which utilizes a calculated (estimated) refractive error. Aberrometer-guided LASIK uses a precise measure of the refractive error to create a customized ablation (tissue removal), eliminating any potential location errors.

This technology is particularly useful for patients who do not have normal vision even though the cornea and the optical nerve show no pathologies or irregularities.