Sunglasses lens Options
- Gradient tint
- Mirror coatings
- Pure mirror and flash mirror
- Sun sensitive
- AR coating
- Clip ons
You can design your own custom prescription sunglasses in the same way that you make your own prescription glasses. Shop for a frame, add a lens with your prescription, and then pick the lens tint and coatings that are best for your needs and lifestyle. Prescription sunglasses are a great way to see in the sunshine.
Before reading this page about prescription sunglasses, it would be a good idea to learn more about building prescription glasses. Begin making prescription sunglasses by selecting a pair of eyeglass frames or sunglass frames that can hold a prescription. Lower quality sunglass frames are not designed to hold a prescription lens, and are called non-RXable. RXable sunglasses are sunglass frames that can accept a prescription lens.
Sunglass frames with an excessive wrap design can only accommodate prescription lenses up to a power of approximately +/-5.00 sphere. You cannot put a prescription is sunglasses with a shield design. Some sunglass manufacturers have facilities to maker prescription lenses for their own frames, like Oakley, Bolle, and Maui Jim. Follow this link to learn more about the features of all eyeglass frames.
Prescription sunglasses can be made with single vision, bifocal, or progressive lenses, and in a variety of lens materials and colors. For more information, follow these links to learn about eye glasses lenses, how to buy eyewear, buying guide, lens wizard, eyeglasses online, eyeglass lenses, lens quality, and how to try on prescription sunglasses. If you have sunglasses and just want new lenses for them, follow this link to read about replacement lenses.
Once you have selected a frame, then choose a lens type (hard resin, polycarbonate, high index, polarized, or sun-sensitive). Hard resin and high index lenses can be tinted easily to any color and tint density you choose. You cannot choose the tints for polarized and sun-sensitive lenses, you must choose between brown and grey.
Polycarbonate lenses cannot easily be tinted. If you want the durability of polycarbonate lenses in your prescription sunglasses, the lens material to choose is called Trivex. It has the same durability as polycarbonate, but it can be tinted to your desire.
Brown and gray are the most popular colors for sunglass lenses. Brown is the best color overall because it allows the wearer the widest light spectrum through to the eye, while blocking blue light and offering optimum contrast. Brown is great for applications where distances need to be constantly judged, like tennis or golf or skiing or other sports requiring acute visual perception and contrast differentiation. Brown is also best for lower light situations, like fishing in the late afternoon or early morning. Grey tint is best for bright light situations like water sports because it blocks out the brightest of the suns rays.
Other colors like green and blue are used more for fashion purposes than for utility. Blue is the overall worst color of all for the wearer because it enhances blue light which creates more glare. If you like blue as a fashion choice, consider a custom-made lens tinted brown but with a blue flash mirror coating. Yellow is used to heighten contrast without blocking too much light, and it is commonly used for shooting and skiing on cloudy days. Boll makes a special green tint that is designed specifically for tennis (the Competivision lens)the green tint helps to accentuate the yellow color of the tennis balls and make the white lines stand out.
Prescription sunglass lenses are tinted by leaving them in a bath of tint solution. The longer they are left in the solution, the darker the tint becomes. Lenses bathed in tint colors can assume just about any color shade or color density. The lens actually absorbs the tint color into the lens material. Tint density is defined as a percentage, where 0% is completely clear, and 100% permits no light to pass through (solid). A 10% to 20% tint is used for a fashion tint, and a 50% to 80% tint is used for outdoor protection from the sun.
For sun protection, you would use a 50% tint for all around use, both during midday and during morning and evening hours when there is less available light. A 50% tint is a better all-around lens. For bright light situations, like midday sun on the water, an 80% tint provides maximum protection from the bright sun.
PRESCRIPTION SUNGLASSES LENS OPTIONS
A gradient tinted lens has a full tint at the top, fading gradually to no tint at all at the bottom of the lens. A double gradient tint is a lens with a full tint at the top and bottom of the lens, and a medium tint in the center of the lens. Double gradient tints are popular with skiers, because the lens blocks glare coming from above (sun) and below (snow), while allowing for a clearer viewing area in the middle.
Prescription sunglasses lenses can receive a coating on the outside that has looks to others like a mirrorit reflects light back away from the wearer. The advantage of this coating is that it serves to reduce the amount of reflected light or glare that makes it harder to see expecially in bright light conditions. For example, when skiing on a sunny day, there is a lot of reflected light and glare coming off the snow.
It is important to know that the wearer does not see the mirror coating from the inside, but only sees the lens tint. For example, if the lenses had a brown tint with a blue mirror, the wearer would see only brown, and other people would see only the blue mirror. This is a useful combination because, optically speaking, blue is the worst tint for seeing objects clearly (brown is best), but blue is fashionable; so the wearer gets the benefit of seeing through a brown tint as well as the benefit of having other people see only the blue mirror coating.
Mirror coatings are a good alternative to polarized lenses, and can be used together with polarized lenses for added protection in extreme conditions. However, using both together will have the effect of darkening the lens and reducing the amount of information your eye receives, which could make it difficult to see is situations where visual acuity is needed (like flying an airplane).
Mirror coatings are available in two ways, as a flash mirror and as a pure mirror. With a pure mirror, other people will not be able to see your eyes; with a flash mirror lens, other people will be able to see your eyes. The pure mirror is a more intense mirror and the flash mirror is less intense.
In both types of mirrors, the wearer does not see the flash color, the color is only seen by other people. For example, if the lenses had a brown tint with a blue flash mirror, the wearer would see only brown, and other people would see only the blue flash mirror. This is a useful combination because, optically speaking, blue is the worst tint for seeing objects clearly (brown is best), but blue is fashionable; so the wearer gets the benefit of seeing through a brown tint as well as the benefit of having other people see only the blue flash coating.
Sun-sensitive lenses are also know by the brand name Transitions, and the technical name photochromic. Sun-sensitive lenses automatically darken to a moderate shade when they are exposed to the ultra-violet rays of direct sunlight. When the direct sunlight is removed, the lenses lighten again. Sun-sensitive lenses are typically only available in brown and grey. Sun-sensitive lenses are available in the normal range of vision correction for prescription sunglasses.
A photochromic lens has some limitations. First, the lens needs ultra-violet light to darken, and it will darken more slowly or incompletely if the lens is not in direct sunlight. For example, if you are wearing a hat, or if it is cloudy, or if you are inside an automobile, the lenses may darken slowly or not completely.
Second, it could take up to eight minutes for lenses to transition from dark back to clear. So if you are in-and-out of the sun, the lenses may not be darkor clearwhen you want them to be. Third, photochromic lenses do not become completely clear indoors, but retain a light tint that may not appeal to people who want completely clear lenses indoors.
Trivex is a great substitute for polycarbonate lenses in prescription sunglasses, because Trivex can be easily tinted but polycarbonate cannot. Trivex is much better suited for tinting and is an excellent choice for rimless drill mounted frames. The suggested prescription range is Plano (0, no Rx) to +/-8.00 sphere.
While Trivex has a slightly lower refractive index than polycarbonate lenses, its specific gravity makes it the lightest of any lens material available today. This means the lens may be a little thicker than polycarbonate lenses but similar in weight. Like polycarbonate lenses, Trivex also has inherent 100% UV protection. However it is optically superior to polycarbonate lenses, meaning it is much less distortive.
Polarized lenses are tinted lenses that block vertical light from hitting your eye and causing eye strain. Hunters, boaters and fishermen, golfers, and drivers are the most common users of polarized lenses. Any surface can create glare in sunlight, including water, sand, snow, windows, vehicles, and buildings. Polarized lenses ease eye stress and fatigue in the sun, and lenses are available in several color and density options. However, in some situations, glare can be beneficial. For example, polarized lenses could make it difficult for a driver to see ice on the road, or for a skier to see ice on the ski slope, or for a seaplane pilot to see the water when landing.
Polarized lenses function similar to window blinds with horizontal slats when open. You view the slats on the edge so they are very thin, and these edges hold the tint color. Polarized lenses block the vertical light that tries to enter your eye from down below or up above, and it only allow the horizontal light to pass through the lens. Polarized lenses are available in the normal range of vision correction for prescription sunglasses.
AR coating goes on the backside (side closest to your face) of prescription sunglasses and non-prescription sunglasses. Backside AR prevents light and glare from coming in to either side and from behind you, bouncing off the inside of the lens and into your eye. This kind of glare is very common in sunny situations, it is extremely disruptive and it is very valuable to eliminate this glare from your vision.
Clip-on sunglass lenses are tinted lenses that clip on to regular prescription glasses, effectively turning them into prescription sunglasses. The clip-ons usually match the eyeglasses frame in shape and color, and attach either by clips or with magnets. Regular clip-ons require two hands to add and remove the clips, but magnetic clip-ons (they hold to the frame with magnets instead of clips) can be added or removed with just one hand.
Clip-ons have advantages and disadvantages. It is convenient to be able to convert your eyeglasses into sunglasses and back again. However, wearing a clip on means adding a significant amount of reflected glare. Light passes through the clip, reflects off the front of the frame, reflects off the back of the clip, and bounces around in there, causing significant additional glare and eyestrain that does not occur with prescription sunglasses.
There are also sunglasses that are designed to fit over your eyeglasses, covering them completely. Fit-overs are useful for eyeglasses that do not have matching clip-ons, and they also serve to block out light from entering around the sides of your glasses. Side-glare is extremely annoying, especially on the water, so fit-overs may be a better solution that sunglass clip-ons.