What is the most common design for both gas perm and rigid lenses?

The most common design for both gas permeable (GP) and rigid contact lenses is the corneal design. This type of lens is specifically shaped to fit over the cornea, providing excellent clarity and comfort. The corneal design allows the lens to align closely with the natural curvature of the eye, ensuring optimal movement with each blink. This proximity to the ocular surface enhances the transmission of oxygen, which is crucial for corneal health, especially with gas permeable materials that allow for higher levels of oxygen flow compared to traditional soft lenses.

In addition to providing excellent visual acuity, the corneal design facilitates a stable fit, reducing the chances of lens displacement during normal eye movement. The design varies in its curvature and diameter to accommodate different eye shapes and conditions. This versatility is why corneal lenses are prevalent in both GP and rigid lens categories.

Other designs, while important in specific contexts or for particular cases, do not serve the same broad application as the corneal design. For example, ancillary or haptic designs might be relevant for specialty lenses or for specific features of wearability, while semi-scleral shapes are typically used for fitting over larger areas or for managing irregular astigmatism, making them less common overall compared to the cor