The days of wearing bifocals or constantly swapping reading glasses may soon be over, thanks to the new ‘smart glasses’ developed by scientists, including one of Indian origin, that can automatically adjust the focus on what a person is seeing, whether it is far away or close.

About the glasses 
1.    The glasses developed by researchers at University of Utah in the U.S. contain lenses made of glycerin, a thick colourless liquid enclosed by flexible rubber-like membranes in the front and back. 
2.    The rear membrane in each lens is connected to a series of three mechanical actuators that push the membrane back and forth like a transparent piston, changing the curvature of the liquid lens and the focal length between the lens and the eye. 
3.    When the wearer looks at an object, the meter instantly measures the distance and tells the actuators how to curve the lenses.
4.    If the user then sees another object that is closer, the distance meter readjusts and tells the actuators to reshape the lens for farsightedness. A rechargeable battery in the frames could last more than 24 hours per charge.