Incorporates two different powers in each lens, usually for near and distance corrections.
Transparent front segment of the eye that covers the iris, pupil and anterior chamber; provides most of an eye's optical power.
A single or multi-layered application of magnesium fluoride to the surface of a lens reducing the amount of light normally reflected from the surface. A must for night driving and computer use.
A physician concerned with and specializing in the medical, optical and surgical care of the eye; treats the structure, function and diseases of the visual system.
Professional who makes and adjusts optical aids, e.g., eyeglass lenses and frames, from refraction prescriptions supplied by an ophthalmologist or optometrist.
Doctors of Optometry are independent primary health providers who examine, diagnose, treat and manage diseases and disorders of the visual system and the eye.
Photochromic Transition Lenses
Lenses that darken when exposed to UV rays and lighten to almost clear when not in the sun.
Higher index lenses that are thinner and lighter; the most impact resistant lens.
Progressive Addition Lens
Type of multi-focal eyeglass lens designed so that power for near gradually increases from zero (in center) to maximum add (in lower portion) with no visible lines.
Scratch Resistant Coating (SRC)
Various materials bonded in thin layers to the surface of most types of plastic lenses to reduce susceptibility to scratching.
An ophthalmic lens designed to provide correction for only one viewing distance.
A multifocal, ophthalmic lens designed to provide correction for three viewing distances; usually for distance, near and intermediate corrections.
Ultraviolet (UV) Rays
Invisible rays from sunlight and some lamps; potentially harmful to eyes, especially related to the development of cataracts.