Lenses with three zones: distance, intermediate and near, are known as trifocal lenses.
Bill Gates wearing glasses?
Yes
Cameras and glasses.
glasses
Please explain the question
His glasses have a concave lens.
No, you cannot change the bifocal prescription on glasses without changing the lens. The lens is what is prescribed by your eye doctor. The frame, however, can be changed.
Glasses are a plural form for glass (a drinking glass, or a lens). To indicate the plural of glasses (eyewear, a pair of eyeglasses), you would have to use the description "pairs of glasses."
convex
Bifocals.
glasses to see the puck
This part is called a Lens, on the camera and the glasses the are made of either optical glass or optical plastic, in the eye the lens in an organic material. Lens allow light to enter the camera, eye or glasses, and focuses that light on a surface such as the camera's film, the eye's retina, and the glasses wearer's eyes.