Washington: The US Food and Drug Administration (FDA) has approved the world's first contact lens that automatically darkens when exposed to bright light.
The Acuvue Oasys Contact Lenses with Transitions Light Intelligent Technology are soft contact lenses indicated for daily use to correct the vision of people with non-diseased eyes who are nearsighted (myopic) or farsighted (hyperopic).
They can be used by people with certain degrees of astigmatism, an abnormal curvature of the eye.
"This contact lens is the first of its kind to incorporate the same technology that is used in eyeglasses that automatically darken in the sun," said Malvina Eydelman, director of the Division of Ophthalmic, and Ear, Nose and Throat Devices at the FDA's Center for Devices and Radiological Health.
The contact lenses contain a photochromic additive that adapts the amount of visible light filtered to the eye based on the amount of ultra-violet light to which they are exposed.
This results in slightly darkened lenses in bright sunlight that automatically return to a regular tint when exposed to normal or dark lighting conditions.
The FDA reviewed scientific evidence including a clinical study of 24 patients that evaluated daytime and nighttime driving performance while wearing the contact lenses.
The results of the study demonstrated there was no evidence of concerns with either driving performance or vision while wearing the lenses.
These contacts are intended for daily wear for up to 14 days. Patients should not sleep in these contact lenses, expose them to water or wear them longer than directed by an eye care professional.
These contacts should not be used as substitutes for UV protective eyewear, the FDA said.
"This innovation was born out of deep research into consumer lifestyle needs and fits our future-forward approach to caring for human sight," said Xiao-Yu Song, Global Head of Research and Development for Johnson & Johnson Vision, the company that developed the contact lenses.