Lenses & Coatings

Anti-Reflective Coating

Normal eyewear often creates glare, distracting reflections, and “ghost images.” Now all that can be eliminated with an anti-reflective coating.

What we see is a result of light being sensed by our eyes. With normal glasses, much of the light reflects off the lenses. This produces glare. It also reduces the wearer’s visual acuity. In other words, the light reflection is both a cosmetic and visual problem.

Anti-reflective coatings increase light transmission through the lenses to 99.5 percent. They make it easier to see and easier for others to see you. These lens coatings are especially useful for those viewing computer screens and driving at night

Bifocal Lenses

For many people, different lenses are needed for seeing at different distances. Bifocal lenses allow the wearer to look through two areas of the lens. One area focuses on distant objects. The other is used for reading.

In a conventional bifocal, the “reading” area is smaller, shaped like a sideways “D” or half circle, and found in the lower hemisphere of the lens. These bifocals are called line bifocals, flat-tops or kryptoks. If you are focusing on distant objects, you look through the top half of the lenses. To read a book, magazine, or newspaper, you look through the “reading” area. Some people find the line separating the distance and near areas distracting. Fortunately, recent technologies have developed a new type of lens, called the no-line, or progressive lens.

Progressive Lenses

A recent improvement on regular bifocals and trifocals is the no-line lens or progressive lens. Progressive lenses provide a smooth transition from focusing on nearby to focusing on distant objects because they do not have a distinct line which separates the focusing powers. Instead, a gradual change in power allows the wearer to focus on objects at all distances. Distant objects are viewed through the upper portion of the lens, intermediate objects are viewed through the middle portion of the lens, while the lowest part of the lens is used for reading at near distances. Although these lenses are adequate for occasional computer use, individuals working for long periods on a computer will usually be better served with a special computer bifocal(see specialized lenses below).

Cosmetic & Specialty Tints

Eyeglasses are not only functional but they can also be a stylish accessory, a part of your personality, or a way for you to be unique. There are a variety of frames to choose from, but you may not know that there are also many ways to improve the appearance of the lenses.

Cosmetic tints are available in a variety of colors and shades. Some lenses have a gradient tint which is clear at the bottom and gradually becomes more colored towards the top of the lens. There are many ways to adjust your lenses to whatever style suits your personality. Some tints are very functional and geared toward specific activities like watersports, skiing or biking.

Recently there has been much attention on a condition called Computer Vision Syndrome, or CVS. A special tint for your glasses can reduce eyestrain associated with CVS.

High Index Lenses

Previous to the last few years, the only materials available for use as lenses were glass and a hard resin called CR-39. But recently, high index lenses have become available. High index materials are named because they have a higher index of light refraction. Basically, they can do the same job that glass or CR-39 does, but high index lenses are much thinner and lighter. With high index lenses, you can avoid having “coke bottle” lenses.

When learning about high index lenses, you may hear many unfamiliar numbers and terms. Here are a few things to remember.

• Polycarbonate: Polycarbonate was originally developed for fighter jet cockpits. It is very strong, very light, and resistant to breaking. It does however scratch very easily, and produces a lot of chromatic aberration which makes it not appropriate for everyday wear. Many safety and sports lenses are made of polycarbonate.
• Mid-Index: Other high index materials are classified by numbers. The higher the number, the thinner and lighter the lens. The lower numbers are classified as mid-index lenses. Mid-index lenses, such as 1.54, 1.56, and 1.57, are thinner than glass, and nearly as strong as CR-39.
• High-Index: High index lenses, such as 1.66, 1.74, and 1.9, are much thinner than regular glass or plastic. Talk with your doctor to decide which high index lens is right for you.

Photochromics (Lenses darken with sunlight)

If you have ever felt frustrated at needing both prescription glasses and prescription sunglasses to accommodate an outdoor lifestyle, you should consider photochromic lenses. Photochromic lenses darken when exposed to UV rays. The change is caused by photochromic molecules that are found throughout the lens or in a coating on the front of the lens. When the wearer goes outside, the lenses darken or tint. When the wearer goes back inside, the glasses become clear.

There are a variety of photochromic lens options available. Depending on what you choose, you can customize the lenses to your needs. Some lenses darken only in direct sunlight, while others darken in little or no direct light. Some are designed to darken while you are in the car to reduce road glare while you are driving. You can even choose the color of the tint. Ask your doctor what options are available.

Polarized Lenses

Glare from wet roads, light reflecting off other vehicles, and glare from your own windshield can be annoying and dangerous. To eliminate this glare, we offer polarized lenses. Polarized lenses eliminate almost all glare, reducing eye strain and increasing visibility. Polarized lenses are the most effective way to reduce glare.

Most glare comes from horizontal surfaces, so the light is “horizontally polarized.” Polarized lenses feature vertically-oriented “polarizers.” These polarizers block the horizontally-polarized light. The result is a glare-reduced view of the world. Polarized lenses can make a world of difference for any outdoor enthusiast. Fisherman can eliminate the bright reflections from the water and actually see into the water more easily than with other sunglasses, golfers can see the green easier, and joggers and bikers can enjoy reduced glare from the road. In addition, drivers can enjoy the safety and comfort that polarized lenses provide while driving.

Scratch Resistant Coating

If you have hard resin lenses (CR-39), you should consider getting a scratch resistant coating. Resins and plastics are more susceptible to scratches than glass. Scratches damage the cosmetic look of the lenses and compromise their performance. With a scratch resistant coating, you do not have to worry as much about minor scratches on your lenses.

Another advantage of scratch resistant coatings is that most coatings come with a one-year warranty. They are a great investment to prevent minor scratches. However, it is important to remember that scratch resistant does not mean scratch-proof. All lenses are susceptible to scratches.

Specialty Lenses

When it comes to selecting glasses, there are different lenses for just about everyone. No matter what your particular need, there is probably a specialty lens designed for you.

For example, a specialty lens that is becoming increasingly useful is designed for computer users. Computer lenses have “windows” designed for viewing your computer screen, documents on your desk, and distant objects. The lenses are designed to reduce Computer Vision Syndrome, or CVS, which is characterized by headaches, eye strain, neck and back aches, dry eyes, blurred vision, and double vision.

Another example is called the double D-segment lens, also known as the double flat-top lens or occupational bifocal. If you look through most of the lens, you can focus on distant objects. But you can also look through a D-shaped segment near the top of the lens to see nearby overhead objects more clearly. This is very useful if you are involved in work where you are looking at nearby objects above your field of vision, as with carpenters and pilots. The D-shaped segment near the bottom of the lens allows for reading.

Trifocal Lenses

Bifocals allow the wearer to read through one area of the lens, and to focus on distant objects through another area of the lens. As the eyes age, though, a stronger prescription is often needed to read. This would be fine, but the stronger prescription that allows for reading makes it difficult to focus on objects at intermediate distances, such as grocery items on a shelf or your speedometer. Trifocals address the problem of intermediate blur by providing a third area in the lens for intermediate focusing.

Trifocals feature three areas of focusing power, each separated from the other by a distinct line. The three windows allow for focusing on distant objects, intermediately distanced objects, and for reading. The downside of trifocals is dealing with the lines between the different focusing powers. Fortunately, the development of progressive lenses provides clear vision at all distances without annoying lines on the lens.