Instead, it uses laser pulses to evaporate microscopic portions of the cornea so that it can change its shape in order to enhance vision. This type of surgery was approved for the treatment of nearsightedness in 1995. For all refractive surgery procedures the eye is anesthetized before surgery using eye drops. Most people say they feel a slight amount of pressure when the laser is on, but absolutely no pain. That discomfort is treated with pain medication when necessary.
Lasers focus a beam of light.
There are different types of lasers whose energy is generated by various kinds of gases. The specific wavelengths of the light produced by the different gases affect different types of tissue. By mixing Argon and Fluoride gases together in an electrically charged cavity, the excimer laser produces a cool beam of highly precise ultraviolet laser. Instead of burning tissue, the excimer actually breaks the chemical bonds between the individual molecules of corneal tissue, all with little or no damage to surrounding cells. This process is known as photoablation, or vaporization using laser light.