| Help Topics : How to Order?
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 | Please Read this before purchasing Prgressive Lenses | |
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| Progressive lenses: |
| Progressive lenses are sometimes called "no-line" bifocals. Progressive lenses are basically trifocals without any visible lines. Progressive lenses were developed because many people wanted the convenience of not having to change their glasses to read, but they did not like other people to see the visible line. |
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| Progressive lens design: |
| Progressive lenses offer the convenience of multifocals, but without the visible line. However, progressive lenses are much harder to use and to adapt to than bifocal or trifocal prescription glasses, and they are much more expensive.
In order to create a no-line progressive lens, there are two large areas of the lens that you cannot see through. Imagine what an hourglass looks like. This is the shape of the area of the progressive lens that you can see through. Objects seen through the areas of the lens to the left and right of the narrow middle section are highly distorted and you cannot see through them.
The bulge areas at the bottom and top of the lens are for near and distance vision, and the thinner "corridor" connecting them is for intermediate distances. On either side of the narrow portion of the hourglass objects will appear blurry. In general, more expensive progressive lenses like Varilux® lens have a wider corridor, and less expensive lenses have a narrower corridor that can restrict the viewing area considerably.
On smaller lens sizes, it is necessary to slice off a portion of the bottom (reading section) of the lens in order to install the lens in the frame. As a result, the smaller the frame size, the smaller will be the reading portion of the lens.
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| Adapting to progressive lenses |
| In order to use a progressive lens, you must learn to move your head to see things; you cannot just move your eyes because you will be looking through a blurry part of the lens. This is called "adapting" to the lens. Most people can adapt within a month, but some people never adapt. It is common to experience dizziness and headaches during the time that you are adapting. Getting accustomed to progressive prescription glasses can be difficult, and you must have proper instruction by an eyecare professional.
Sometimes, people who try progressive prescription lenses for the first time have a difficult time learning to look through the appropriate portion of the lens at the right time. Often a simple fitting adjustment to your prescription eyewear by your local optical professional can make all the difference.
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