Progressive lenses, on the other hand, have many more lens powers than bifocals or trifocals, and there's a gradual change in power from point to point across the surface of the lens.
It provides clear vision at all distances rather than at just two or three distinct viewing distances. It eliminates bothersome "image jump" caused by bifocals and trifocals. This is where objects abruptly change in clarity and apparent position when your eyes move across the visible lines in these lenses.
Because there are no visible "bifocal lines" in progressive lenses, they give you a more youthful appearance than bifocals or trifocals. This reason alone may be why more people today wear progressive lenses than the number who wear bifocal and trifocals combined.
Today's premium progressive lenses also are very comfortable to wear. This is especially true of modern "free-form" progressive lenses made with digital design and production tools.
A professional optician can help you select the best progressive lens brand and design for your eyeglasses prescription and your unique visual needs. In particular, modern progressive lenses are preferred for anyone who wants the latest technology in multifocal vision correction and also wants the most appealing eyeglasses possible with no old-fashioned lines in the lenses. Typically, these lenses are more expensive than a bifocal.
Prices may also vary by region and eyeglass company. Buying online may be an option; however, it can also have some risks. To work properly, progressive lenses need to be measured to your eyes and that can be difficult to accomplish online. You might also consider that a study by the American Optometric Association revealed that For best results, consider working with a skilled optician who can help you choose the best frame and lens type for you. Some people never adjust to wearing a progressive lens.
If this happens to you, you may experience constant dizziness, problems with depth perception, and peripheral distortion. Instead, you might require occupational or computer progressive lens, which provides a stronger strength for intermediate distances. This can reduce eyestrain and eye fatigue. The only way to know if progressive lenses will work for you is to try them and see how your eyes adjust. If problems continue, a bifocal lens might be a better fit for you.
To help your eyes adjust, wear your progressive lens as often as possible in the beginning. Also, get into the habit of turning your head to look at objects instead of moving your eyes from side to side. Peering out the side of the glasses can distort your vision. Eyeglass technology is always improving. The age-related onset of conditions like presbyopia causes the primary need for progressive or bifocal lenses.
Although, both bifocal and progressive lenses are used to combat the effects of presbyopia and provide comfortable vision for individuals with multiple prescriptions, it is important to review your lifestyle to determine the best option for you. Progressive lenses provide the most natural vision for the wearer by seamlessly transitioning between near and far prescriptions within the lens.
Whereas, a bifocal lens is separated into distinct areas of near-and-far-vision prescriptions. Many optometrists and opticians also recommend that when you purchase progressive lenses you should buy the best the optical store has to offer. Vision distortions, narrow viewing areas and the inability to adjust to your progressive lenses are much more common with inferior quality brands of progressive lenses.
Patients must learn about progressive lenses so they can understand how to use them and what to expect. Remember to point your nose directly at what you want to see. Then raise or lower your chin until the object comes into the best focus. You may feel an initial difference in peripheral vision that will require some slight changes in horizontal head and eye movement.
This will diminish with wearing time. Most people will adapt in a few hours although some can require as long as two weeks. If you are not adapted within two weeks you should return for a consultation with the optician that fitted your eyeglass frames to your face. If the initial frame measurements are slightly displaced you will not be looking through the proper part of the progressive lens. Therefore, you will experience blurred vision or an inability to feel right visually when wearing the lenses.
A new measurement for the position of the lens and remaking the lens or adjusting the frame should solve the problem. See "Types of Progressive Lenses" below for more information.
The design of progressive lenses will allow you to see clearly at all distances, but it also creates aberrations in the lower periphery of the lens. These aberrations will cause slight blur and distortion and are more obvious when looking far right or left especially through the bottom of the lens. You can see these peripheral zones as the light colored areas in the diagram above. As a progressive lens wearer looks through the distance, intermediate and near zones of the lens everything is clear and in focus.
The transition between different distances is smooth and natural. This peripheral distortion may also cause a "swimming" feeling at first which should go away with adaptation.
Progressive designs have improved greatly in the past few years and most first-time wearers have no problems at all. If you do have blur or a swimming feeling, it will help to point your nose at whatever you are looking at in order to avoid looking through the periphery of the lens.
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