Final answer:
LASIK treatment improves eyesight by reshaping the cornea using an excimer laser to correct the focus of light onto the retina, similar to the function of spectacles but with a permanent effect.
Step-by-step explanation:
LASIK treatment functions to improve eyesight primarily by altering the shape of the cornea, which has the highest refractive power in the eye, accounting for about two-thirds of the eye's overall power. This procedure, known as Laser-Assisted in situ Keratomileusis (LASIK), utilizes precise ultraviolet radiation from an excimer laser to ablate and reshape the cornea. For nearsightedness, the cornea is flattened, reducing its power, and for farsightedness, the curvature of the cornea is increased to enhance the power of the eye. These modifications correct the way light is focused onto the retina, similar to how lenses in spectacles would. Laser vision correction is computer-controlled and requires a detailed assessment of the patient's vision, leading to less invasive and quicker healing periods.