What should the edge thickness of rigid gas permeable lenses generally be?

The edge thickness of rigid gas permeable (RGP) lenses is an important factor that impacts both the lens performance and patient comfort. Generally, the acceptable edge thickness range for RGP lenses is between 0.08 mm and 0.12 mm. This range allows for a balance between structural integrity, which helps prevent chipping or cracking, and maintaining a smooth edge that enhances comfort and reduces the risk of irritation to the eyelid during blinking.

An edge thickness within this range optimizes the lens's ability to distribute tears evenly beneath the lens and supports appropriate tear interchange, which is critical for maintaining corneal health. Thinner edges can be more comfortable for the wearer but may compromise durability, while edges that are too thick can lead to discomfort or an undesired appearance.

While the other options present a measure of edge thickness, they do not fall within the ideal range for RGP lenses. Therefore, understanding that the edge thickness of 0.08 - 0.12 mm is optimal for these lenses, promotes both patient satisfaction and effective vision correction.