Researchers in Switzerland are working to develop magnifying contact lenses that zoom in and out with a wink.
The innovative new vision-enhancing system, the first of its kind, includes a set of telescopic lenses and smart glasses that can distinguish between blinks and winks so that the user can easily flick between zoomed and normal vision.
The visual aids, which are still in the prototype stage, could be useful for those with visual impairment, which affects some 285 million people worldwide. In particular, they might one day help people with a condition called age-related macular degeneration (AMD), which is the leading cause visual impairment in adults over the age of 50. AMD is a progressive disease in which people gradually loss their central vision due to cell damage and death in the retina. Although there are glasses in existence to help those with this condition, known as bioptic telescopes, they’re bulky and can interfere with social interaction. This new system, however, is designed to be much less intrusive.
The magnified optical path incorporates a telescopic arrangement of positive and negative annular concentric reflectors to achieve 2.8x magnification on the eye, while light passing through a central clear aperture provides unmagnified vision.
AMD is a medical condition that leads to the gradual loss of central vision caused by retinal damage. It is the leading cause of blindness among older adults in the western world. Patients suffer from blurry vision – with particular difficulty in reading and recognizing faces as the disease progresses – although their peripheral vision remains unaffected. Regular contact lenses do not provide any relief because they cannot restore the lost vision merely by correcting the eye’s focus.
To fill the niche between surgery and the bulky mount, optical-engineer Eric Tremblay of the Ecole Polytechnique Fédérale de Lausanne (EPFL) in Switzerland, along with colleagues in the US, has designed and built the first contact lens that incorporates a telescope. Tremblay’s new system uses tightly fitting mirror surfaces to make a telescope that is integrated into a contact lens just over a millimetre thick. The lenses’ arrangement is such that it has two modes. The centre of the lens provides unmagnified vision, while the ring-shaped telescope, which is at the periphery of the regular contact lens, magnifies the view 2.8 times.