Depth perception is your ability to create a three dimensional view of the world. Your brain is able to create this three dimensional model by using all of the visual data that it receives from your eyes. Patients who have refractive errors such as myopia, hyperopia, or astigmatism may have difficulty with depth perception even if they are wearing their glasses or contacts.
Studies have shown that eliminating refractive errors and improving the eyesight in each eye can lead to better depth perception after laser eye surgery. If each eye is able to deliver a clear image to the brain, then the brain is better able to superimpose these images to create one focused image with three dimensionality.