Bifocal–Corrective lenses containing regions with two different optical strengths.
Bridge Size–The width between the lenses of a frame. Manufacturers typically measure this width at the widest point between the two lenses.
Clip-On–A small device with sunglasses lenses that hooks onto your prescription eyeglasses.
Color-Coated–Lenses that have a color coating applied to the outside of the lens.
Contrast–The difference in brightness between the light and dark parts of an image. A higher contrast lens provides greater visual acuity.
Eye Size–The horizontal measurement of the lens on
Glass–Glass lenses are scratch resistant, but are double the weight of plastic lenses. Glass lenses have excellent optical qualities and can have a refractive index as high as 1.90.
Nylon Frames–A rugged, resilient, strong, flexible, lightweight material used in frames that retains its shape and withstands extreme temperatures.
Light Adjusting–Light Adjusting lenses do not darken as much as transitional lenses do outside. Light adjusting lenses will darken in direct sunlight only.
Nose Pad–The pad mounted to eyewear on either side of the nose that helps to support the frames.
Photochromic–Photochromic lenses are optical lenses that darken on exposure to specific types of light of sufficient intensity, most commonly ultraviolet (UV) radiation. In the absence of activating light the lenses return to their clear state. Photochromic lenses may be made of glass, polycarbonate, or another plastic. They are principally used in sunglasses that are dark in bright sunlight, but clear in low ambient light conditions. They darken significantly within about a minute of exposure to bright light, and take somewhat longer to clear.
Plastic–Plastic lenses are much lighter and less breakable than glass lenses. Traditional plastic lenses are made from a hard resin that is cast or molded in the wet state into lens blanks, which can be ground into specific shapes to fit any lens frame. Plastic lenses are great for prescription sunglasses due to their tint ability factor.
Polycarbonate–High-index plastic lenses that are thinner and have flatter prescription curves and require a hard backside coating to protect them from scratching.
Polarized–Polarized lenses possess a filter that reduces the amount of reflected light that enters the eye. This filter reduces reflected glare which is most noticeable on water, snow, or concrete and asphalt surfaces.
Polycarbonate–Polycarbonate lenses are the most impact resistant material. They are lightweight, have built in UV protection, and recommended for children, sports, as well as rimless frames.
Progressive–These are no-line bifocals. There is no discernible line between the regions of optical power on the corrective lens with progressive lenses.
Scratch Resistant–A coating that makes lenses less prone to scratching.
Temple Length–The length of the arm of the frame running from the hinge to the end that wraps behind your ear.
Transition Lenses–Light adjusting lenses or photochromic lenses change from clear indoors to dark outdoors. Transition lenses block 100% of the sun's harmful UVA & UVB rays.
Trivex–Trivex lens is a revolutionary material that lets you prescribe a single, thin lens with the qualities of many. Trivex is recommended for prescriptions with a higher number as it is thinner than Polycarbonate.
UV Filter–A lens coating, either on or embedded in the lens that filters UV radiation.