General FAQ About Vision
& About This Website
Below are our most frequently asked questions about vision, eye health, and this website. We also have FAQ pages on cataracts, contact lenses, diabetic retinopathy, eyeglasses, glaucoma, laser eye surgery, macular degeneration and sunglasses.
I have "spots" floating around in my eye. Should I be worried?
Spots and floaters are usually harmless. Read our Spots & Floaters article for details about the causes and symptoms, and how to determine if you need to see your eye doctor.
I work on a computer all day. Can this hurt my eyes?
Computer monitors emit levels of radiation that are considerably lower than the maximum allowed for safety, according to a study by the National Institute for Occupational Safety and Health. NIOSH compared the maximum radiation levels in a group of monitors with the safety standards.
A study of monitors reported in the Optical Laboratories Association CLEARVisions magazine found that:
- X-rays: none
- Ultraviolet: more than 1,000 times below the standard
- Visible: more than 10 times below the standard
- Infrared: none
- Radio Frequency:
- Electrical Field: 5,000 V/meter2 of 377,000 allowed
- Magnetic Field: .09 A/meter2 of 2.65 allowed
- Extremely Low Frequency: equal to common household appliances, well below dangerous levels (no standard exists)
[Read about how to minimize eye irritation from computer use.]
I'm interested in having LASIK done. What information do I need to know?
We have a wealth of information in our LASIK & Vision Surgery section.
Can you tell me what's wrong with my eyes?
Sorry, but no. It's not that we don't want to help you, but it would be irresponsible to try to diagnose your problem without examining your eyes. However, we do have some tips:
- If you are having any kind of problem, the first thing you should do is schedule an appointment with your eye doctor to discuss your symptoms.
- Before your appointment, you might want to use our our symptom finder to research your symptoms. Also try the site search.
- If you suspect a specific problem or disease, read more about it in our Eye Problems & Diseases section.
My doctor refused to give me my contact lens prescription. Is this legal?
Until recently, laws on this issue varied from state to state in the United States. Some eye doctors felt that if they gave out contact lens prescriptions, some of their patients would stop going in for regular eye exams. These check-ups are important, because they not only detect prescription changes, but they can also catch serious diseases in their early, more treatable stages.
But in February 2004 a federal law went into effect that gave all U.S. consumers the right to have a copy of their contact lens prescription, without even asking for it. Find out more about this contact lens legislation and what it means to you.
Am I old enough to wear contact lenses?
That depends on how responsible you are; this decision is best made jointly between you, your parents and your eye doctor. Please see our Contact Lenses for Kids article for more information.
What exactly does "20/20 vision" mean?
"20/20 vision" is commonly accepted as the standard of normal distance vision for a human being. Basically it means "good visual acuity at 20 feet." So if your vision is 20/20, you can read certain sizes of letters on a Snellen chart clearly at 20 feet or closer. But if your friend has 20/15 vision, his visual acuity is better than yours: you would have to stand 15 feet away from the chart to read the smaller letters that he can read while standing 20 feet away. Conversely, someone with 20/30 vision has worse distance vision than you.
By the way, visual acuity at a distance isn't the only measure of how good your vision is. You could have 20/20 distance vision but still have difficulty seeing at night because of poor contrast sensitivity. Or you could have near vision problems because you're over 40 and experiencing presbyopia.
Questions About This Website
How can I check a doctor's credentials or find out about any complaints against him or her?
You may contact:
- Your state's optometric association (for optometrists)
- Your state's medical association (for ophthalmologists)
- The Better Business Bureau (for complaints)
Can you help me find a doctor near me who...?
We don't have a master list of doctors, but most people find these two pages quite useful:
If you don't find what you're looking for on those pages, your best bet is to call the eye doctors or optical stores near you to see if they'll be able to help you.
I'm looking for a specific type of contact lens. Do you know where I can find it?
We get two different types of questions like this: some people describe the type of lens they're looking for and want to know if it exists; others know that the lens exists and want to know how to get it (usually, you're looking for special-effect contact lenses).
If you know the lens exists, you must visit your eye doctor to get it, even if you don't need vision correction.
Why? The FDA considers them medical devices because you put them in your eyes, and has put guidelines in effect for your safety. Plus, each contact lens and each person's eyes are a little different, so the doctor needs to perform a specialized fitting for you.
By the way, if you want to see the latest special-effect contacts, please read our Theatrical & Costume Contact Lenses article.
Do you carry...?
Our company does not sell any products.
I saw a product featured on your site that I'd like to buy. How do I go about it?
We don't sell any products, but most of the products we cover are available from your eye doctor or an optical store. Occasionally in our What's New pages, we cover products that are available elsewhere; if so, the specific locations will be listed at the end of the piece.
I have an older browser, and I have trouble viewing some of the graphics on your site.
You need a modern browser to have full access to the information on this site, as well as many other sites on the Internet. This website is best viewed in Internet Explorer 6.0 and higher, as well as all recent versions of Firefox, Netscape, Safari, etc. You will have problems if you use an older browser such as Internet Explorer 5.x, Netscape 5.x, etc.
When I print articles from your website to read later, they don't look like they do on the screen.
True. We designed our web pages to print in a way that is most useful to our readers. Therefore, we blocked the navigation menu and other such items from printing. And we eliminated most colors except black, so our pages wouldn't use up the color inks in your printer unnecessarily.
Because of browser limitations, web pages usually don't print perfectly. This is true across the Internet, not just for our website. Printing our web pages in Firefox, Chrome and Safari works best. But Internet Explorer, especially version 9, can be problematic.
If a web page prints too small for you to read, you might need to adjust a browser setting. For example, in Firefox version 9, click on "File" in the menu at upper left, then choose "Print Preview." Make sure that "Scale" is set to 100%, rather than "Shrink To Fit."
Can you send me information for my school project?
You may use our website for research purposes (please credit us as your source), but we do not have any brochures to send out. Recommended starting points:
Is it OK to copy your text and images?
You may print pages of our website for your own personal use. That is the only acceptable reproduction of our copyrighted material. You may also link from your website to any page(s) on our website. No other use of our material is acceptable. Your use of our material is illegal even if you mention All About Vision as the source, or include the author's byline. We take our copyrights seriously and constantly monitor the Internet for instances of infringement. For more information, please read our copyright infringement policy.
For questions not covered on our FAQ pages, you may wish to visit our Ask the Eye Doc columns.
[Page updated January 2012]
For more Eye and Vision Information articles, please visit this section's home page or use the search box below.