In the myopic eye, light rays converge to a single point in front of the retina. The resulting vision is not clear. You can see close objects better than those at a distance. This flattening may be done in one of two ways. With the curvature of the central cornea reduced, light rays converge further back in the eye, ideally on the retina rather than in front of the retina resulting in a reduction in nearsightedness.
Ordinary light is made up of a broad range of wavelengths and has relatively low energy.
A laser produces a very intense beam of light of one wavelength in the light spectrum that can be focused into a small region. The excimer laser uses a mixture of argon and fluorine gases to produce a narrow uniform beam of invisible ultraviolet light energy, which when focused through a lens system onto the surface of the cornea, produces vaporization of corneal tissue. The excimer laser light energy does not produce heat, but breaks molecular bonds and vaporizes tissue a few molecular layers at a time. This process is called photoablation . Star 2 Laser.