A lens with a hollow shape like the inside surface of a ball. Concave lenses are minus power lenses and are used to correct myopia (nearsighted, shortsighted vision).
A lens with a bulging surface like the outer surface of a ball. Convex lenses are plus power lenses and are used to correct hyperopia or farsightedness. Also used for reading ...
The right lens is just as important as the frame shape, color or size. The lens choice will determine the thickness and visual accuracy of your prescription. FramesDirect.com ...
An antiquated technology used in situations requiring such high plus power that a full field meniscus lens would be impractical (because of thickness, weight and fit). This area ...
is the color formed by mixing red and green light. Yellow is complimentary to blue, and is one of the three colors used in subtractive color synthesis.
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