LASIK Up-to-date Newsletter

FreeVis Simulator for twilight and night vision after LASIK or PRK / LASEK

LASIK is perfectly suited to correct low or average myopia, and low hyperopia. Even at dusk or night, visual acuity remains as before LASIK. However, LASIK has limits depending on the rate of nearsightedness and/or farsightedness, and the diameter of the pupil. It is possible that with severe nearsightedness and/or farsightedness, and a very wide pupil, halos may occur during dusk and at night, which, under certain circumstances, might decrease visual acuity.

A halo is created due the incorrect ratio between the size of the cornea zone that was “smoothed” with the Excimer Laser, and the diameter of the pupil at night. If the pupil becomes larger than the “smoothed” cornea zone, a halo occurs because one part of the light entering the eye is displayed as a blur.

FreeVis would like to demonstrate the causes are for this, and how they influence visual acuity. We are providing a simulator that illustrates visual acuity, depending on your visual disorder, and the pupil diameter in the dark.

The illustrated traffic situation contains all typical light sources in street traffic: brake lights, traffic lights and headlights of approaching vehicles. Each simulated picture shows the contrast of the same traffic situation from a person with normal vision, from a person with ametropia without glasses / contact lenses, as well as after LASIK . This gives a general picture of the extent of the possible glare.

Start the FreeVis simulator here!