What 20/20 Means
Vision that is 20/20 describes a normal level of clarity and sharpness in your vision. This is called visual acuity. This measurement offers a way to compare the quality of your vision to a professional standard. Using this tool helps us to accurately gauge whether you need corrective lenses and to diagnose eye conditions. The term 20/20 means that you can see an object clearly when it's 20 feet away from you, just like normal. If your vision is 20/100, then viewing an object from 100 feet away is too far for you but fine for others; to see it clearly, you must come within 20 feet of that object.
Is 20/20 Perfect Vision?
No, 20/20 only refers to how well you see things at a distance. Your overall visual ability depends on a number of other factors as well, such as:
How Is Visual Acuity Measured?
Your optometry clinic has several tests that can check your visual acuity. A common test consists of a chart with letters that become smaller as you read further down the page. Each line of letters corresponds to a level of visual acuity. If the "20/20" line looks blurry to you, then you may have impaired vision.
How Is Impaired Vision Corrected?
If your impaired vision is not caused by a medical condition such as diabetes, then your eye care provider can help you determine the best choice for your case. Common options include:
If you lack 20/20 vision, corrective aids can adjust your eyesight to create clearer vision. This will help keep you safe and prevent eyestrain, which can cause headaches and fatigue. Working with your eye care provider is the best way to determine whether your vision should be corrected.
Many “silent” diseases, such as glaucoma and diabetes, can only be detected through regular eye exams. When these conditions are discovered earlier rather than later, they become easier to treat or manage, allowing for better long-term preservation of eyesight.
In addition, reading glasses from the drugstore often do not work well because most people have astigmatism and/or different prescriptions in each eye. As a result, many of these individuals experience persistent eye fatigue and headaches. Forgoing the eye exam also sacrifices the opportunity to screen for treatable diseases, as mentioned above.
How often do I need to get new eye glasses?
This depends on a number of personal factors, such as changing needs, tastes or lifestyle, but you should visit your eye doctor at least once each year. If you notice problems with vision or headaches, then it’s best to consult your doctor right away for a full evaluation and new glasses, if needed.
Unfortunately, you probably will unless you elect to use contact lenses or corrective laser eye surgery. The great news is that there are lens and surgical advancements in optometry everyday.
What are bifocal eyeglasses and multifocal eyeglasses?
These eyeglasses combine two or more prescriptions into one pair of glasses to correct vision problems at different distances. Most commonly, bifocals are recommended so the wearer does not have to switch between separate eye glasses for distance viewing and for reading.
How can I tell if I need bifocals?
Bifocals and progressive lenses are most often prescribed for presbyopia in those over age 40 and for individuals who have trouble seeing clearly both at a distance and when reading. Bifocals can also help a person who over-crosses his or her eyes when viewing close objects. An eye exam with a qualified eye doctor can assist you with determining whether bifocals are right for you.
How are bifocal eyeglasses made?
Traditional bifocal lenses are constructed by molding the reading segment into the primary lens, which is used for distance viewing. The resulting lens contains a visible line where the two lens prescriptions meet.
How can I put on bifocal eyeglasses without the line getting in the way?
Try putting the glasses on, then looking through the upper segment for a moment to focus for distance. Next, without moving your head at all, lower your eyes to look through the bottom segment; hold this article or a book 18 inches away from your face and downwards by a 30-degree angle, and read through the bottom portion of the lens. The more you repeat this procedure, the more easily your eyes and brain will adapt to the new reading technique.
How long will it take to get used to bifocals?
As you adjust to bifocal or multifocal eyeglasses, you will need to learn to tilt your head or move only your eyes in order to bring the appropriate lens into the center of your visual field. For most wearers, it takes about 3 weeks to develop and use these new habits naturally. However, most people find the convenience and clear vision well worth the effort.
Instead of bifocals, can I use progressive lenses and choose a smaller eye glass frame?
Yes. Progressive lenses offer more precision in your viewing range within a smaller lens diameter. However, some frames are too small for a proper fit; a trained optician can work with you to find a frame that is sized correctly for both your lens and your face shape.
What are progressive bifocal lenses?
Progressive bifocal lenses transition gradually from the reading lens to the distance prescription to eliminate the horizontal line that is visible in traditional bifocals.
Why are the lenses so thick?
The final lens thickness depends on the strength of your prescription, the size of your frame, and your personal measurements. Fortunately, recent innovations in lens designs and materials have made lenses thinner by up to 60% in some cases. If lens thickness is a concern for you, notify the optometry staff member; he or she will help you select a frame and lens that allow you to use a thinner lens.
If you often experience glare when wearing your glasses, an anti-reflective coating may be a good choice. This lens coating is a microscopically thin layer that prevents light from reflecting off of the front and back surfaces of your lenses. This can dramatically improve vision for night driving and may also make it more comfortable to read or use a computer. Anti-reflective coating is especially helpful for high-index or polycarbonate lenses, which tend to reflect more light.
If you’ve scratched your eyeglass lenses, you know how irritating it can be to look out into the world with sub-optimal vision. Scratch-resistant lenses have a clear coating that prevent minor scratches on the front and back surfaces of the lens. Be aware that even a scratch-resistant coating cannot prevent all scratches or lens damage; however, it can be very helpful in preventing minor wear on your lenses.
It is just as important to protect your eyes from ultraviolet light exposure as it is your skin. UV-protective lens treatments block many of the harmful ultraviolet rays from damaging your eyes. This may reduce your risk of retinal damage, cataracts, and other eye problems. Discuss your UV protection in your next optometry exam to determine if ultraviolet light-blocking lens treatment might be appropriate for you.
Do you frequently step in from the cold, only to have to wait a few minutes for your lenses to clear before you can see properly? Foggy lenses are a problem in cold climates as well as those with steamy conditions. An anti-fog lens coating eliminates this issue by preventing the lens surface from developing condensation. There are fewer options for anti-fog lenses, because this technology continues to develop. However, an anti-fog coating may be perfect for someone who plays sports or frequently transitions from a cold environment to a warm room.
What to Look for in Reading Glasses
Reading glasses correct presbyopia by helping light properly reflect onto your retinas, improving your focus on near objects. Typically, reading glasses are worn only when reading, doing needlework, or performing tasks which require concentrating on materials close up. Some reading glasses are full frames, which must be taken on and off when transitioning from close-up work to distance vision. Others are half frames, which permit you to shift your gaze appropriately to achieve the best vision.
Although drug stores and even supermarkets commonly stock reading glasses, it is important to get a thorough eye exam before making a purchase. An eye care provider can detect other age-related changes that may be affecting your vision. Prescription reading glasses can account for differences between your eyes as well as astigmatism. Consult your eye doctor for a thorough optometry exam before investing in a pair of reading glasses.
What Causes Age-Related Eye Changes?
The lens of your eye is a flexible disk that changes shape to focus light onto the retina. Over time, the lens naturally becomes thicker and less flexible because of changes to the proteins in the lens. The muscle fibers attached to the lens also change with age, making it less flexible. The result is a harder, more rigid lens that cannot properly refract light and focus on near objects. This leads to blurred vision when looking at close objects, a condition technically called presbyopia.
What If My Eyes Are Already Corrected?
In many cases, individuals already wear glasses or contact lenses to correct their vision. Whether you had 20/20 eyesight in your younger years or had laser surgery to correct your vision, age-related presbyopia may affect you. The condition often develops after the age of 40, although some people maintain perfect eyesight into older adulthood.
Are Contact Lenses For Me?
Contact lenses are a safe and popular choice for vision correction. Whether you just found out that you need vision correction or you’ve been wearing glasses for several years, switching to contacts can be an easy, painless choice. Understanding the basics about contact lenses allows you to consult with your eye care provider and make the choice that is best for your lifestyle.
Can I wear contact lenses?
Most people are able to wear contact lenses safely and comfortably. There are contact lenses that correct for nearsightedness, farsightedness, astigmatism, and other vision problems. An optometry exam can determine what lenses are appropriate for you.
Are contact lenses safe for my eyes?
Millions of people wear contact lenses without any difficulties. Following recommendations for inserting, removing, cleaning, storing, and replacing contacts typically keeps your eyes safe and healthy. However, you should talk to your eye doctor if you have specific concerns about contact lens safety.
What is the difference between hard and soft contact lenses?
Soft contact lenses are made of plastic combined with water. Soft lenses allow oxygen to pass through the material to your cornea, nourishing and soothing the surface of your eye. Rigid gas permeable contact lenses, sometimes called “hard lenses” are made from a stiffer, oxygen-permeable material. They are often used by individuals with astigmatism or higher-order aberrations.
How often should I change my contact lenses?
The frequency with which you should dispose of lenses depends on the contact lens type. Some lenses are made to be disposed of each night, while others may last several weeks. Talk to your eye doctor and read the instructions on your contact lens package to determine the replacement schedule for your lenses.
Is it possible to lose a contact behind my eye?
No. If you rub your eyes or swim underwater with contacts, it is possible to dislodge your contacts. Usually, they can be found under your upper eyelid and removed without difficulty.
How long does it take to adjust to wearing contacts?
If you’re not used to wearing contacts, you may notice them or feel slight discomfort for a day or two. As you become accustomed to the contact lenses, you will no longer even notice that they’re there.
There are a lot of variables to consider when choosing contact lenses. Think about your typical routine and consult with your eye care provider to find the perfect contact lenses for your lifestyle.
If you find yourself struggling to see both at far distances and nearby reading materials, then it may be time to consider bifocals. Your eye care provider and the trained optometry staff will work with you to determine the best way to meet your needs while helping you to look and feel your best.
Bifocal contact lenses are a type of contact lens that combine two different prescriptions in the same lens. One component corrects nearsightedness and the other prescription addresses farsightedness or farsightedness. Several types of bifocal contacts are available; your eye care provider can help you determine which option is best for you.
What Kind of Bifocal Contacts Should I Wear?
At your optometry clinic, you'll be able to explore your options fully. Generally, several factors influence the type of bifocal contacts that are right for you, including:
What Should I Expect During the Adjustment Period?
Some people adjust quickly while others need some time. You might notice that images jump when you switch between close-up and distance vision, or you might see a ghost image when you read. You might see a halo around lights, or your vision might change when the lens moves on your eyeball. If you experience any of these quirks, talk with your eye care provider. Sometimes, these effects are part of adapting to your new corrective lenses and will go away with time. However, in some cases, you might need to try a different type of lens.
If you're having trouble seeing clearly both up-close and at far distances then bifocal contact lenses offer a convenient alternative to bifocal eyeglasses. It may take longer to adjust to bifocal contacts than to glasses, but many find that it's a worthwhile investment.
Colored contact lenses allow you to temporarily change your eye color whether or not you need to correct impaired vision. In this way, you can create a more subtle eye appearance, wear a crazy design for special occasions, or just enjoy a new eye color.
Will Colored Contacts Change the Way I See?
Yes, but only if your colored contacts also contain a prescription to correct nearsightedness, farsightedness or astigmatism. Whether you have prescriptive lenses or cosmetic colored lenses, the center of the lens remains colorless to avoid affecting how you see. Only the part that covers your iris, or the colored part of your eye, contains color; that's what changes your visible eye color.
Will Colored Contacts Look Natural?
Yes, most colored contact lenses use lines, dots and other shapes to mimic the pattern of your iris.
What Kinds of Tints Are Available?
At your optometry clinic, you may choose from three types of tints:
What Colors Are Available?
The most commonly selected colors are green, blue, hazel, violet, amethyst, gray and brown. Theatrical contact lenses can create special effects for movies and costumes to make you look like a vampire or alien. However, theatrical contact lenses are still a medical device—they should never be shared with anyone.
If you're thinking about color contact lenses, your eye care provider can help you select the right type of colored contacts depending on your eye color, quality of vision and desired appearance.