(especially of lenses in spectacles) design for both distant and near vision

glass for vision

a straight line that joins two points on the circumference of a circle or the ends of an arc

arched, rounded line or object

a line of which no part is straight, e.g. part of the edge of a circle

arched, rounded line or object

a curve of two equal parts formed by cutting through both bases of a double cone

arched, rounded line or object

a piece of glass (or substance like glass) with one or both sides curved, used in spectacles, cameras, telescopes, microscopes and other optical instruments

glass for vision

a flat curve formed by cutting a cone along a line parallel to its side

arched, rounded line or object