Glasses and contact lenses have become an inherent ... These electric signals travel through the optic nerve to the brain, ...

It is the most common type of glaucoma, a set of eye diseases that affect the eye's optic nerve. The optic nerve is located at the back of the eye and sends visual messages to the brain.

The microchip receives an infrared signal from a camera lens on a pair of glasses connected to the optic nerve. Ms Irvine, 68, said getting onto the trial was like "winning the lottery." ...