Technically, the glasses have a distance sensor embedded into the front of the frame and continually adjust the focus of the lenses ... plano-convex or plano-concave lenses, and can do so quickly ...

Instead of a concave lens near the eye, Kepler used a convex ... cheered the coming day when aerial telescopes would have a focus of 1,000 feet and human spectators could marvel at the antics ...

Concave lenses correct myopia by being thin at the centre and thick at the edge. It diverges light rays entering the eye so they focus further back, landing directly on the retina instead of in ...

In both cases, rays of light do not focus on the retina so a clear image ... Short-sightedness can be corrected by placing a concave lens in front of the eye, as shown in the diagrams below.

This is because the eye refracts the light and brings it to a focus before it reaches the retina. This is corrected by using a concave or a diverging lens. People who are ‘long sighted’ can ...