HYPEROPIA (farsightedness)
Hyperopia, or farsightedness, occurs when light rays are not sufficiently bent to focus on the retina. This means that without glasses or contact lenses, it is difficult to see when look far away, but it is even worse when looking up close.

To correct farsightedness, the central cornea must be made steeper. This is achieved by directing the laser beam to remove tissue from around the central cornea.

MYOPIA (nearsightedness)
Myopia, or nearsightedness, occurs when light rays are bent too powerfully, and the image is focused in front of the retina instead of directly on the retina. This means that without glasses or contact lenses, it is difficult to see far away, but the vision is clear when looking up close.

To correct nearsightedness, the cornea must be made flatter. This is achieved by removing tissue from the center of the cornea.

ASTIGMATISM
Astigmatism occurs when light rays are focused at more than one point on the retina. This occurs when the cornea has a slightly oval shape. This means that without glasses or contact lenses, it may be difficult to see far away or up close, and the image may be distorted.

To treat astigmatism, the cornea must be made more round. This is achieved by removing more tissue from one part of the cornea than another.