Hard gas-permeable contact lens. Close-up of hard gas-permeable contact lens on a finger. The lens is a thin,shell-like transparent disc made of glass or plastic that fits over the cornea. Conta- ct lenses are worn against the eye,separated by a thin film of fluid. They are used to correct defe- ctive vision such as short sight. There are two other types of contact lens: hard & soft. Hard gas-permeable lenses have the same visual qualities as hard lenses,but are easier to wear as oxygen is allowed through the lens to the eye. Some people cannot use contact lenses as they have sensitive eyes,or difficult optical requirements | |
Lizenzart: | Lizenzpflichtig |
Credit: | Science Photo Library / Shemilt, Jane |
Bildgröße: | 3314 px × 2362 px |
Modell-Rechte: | nicht erforderlich |
Eigentums-Rechte: | nicht erforderlich |
Restrictions: | - |