There’s more to a full eye exam than just reading letters from a chart. Many people do not get fully comprehensive eye exams, instead opting for the vision acuity tests necessary to determine an accurate prescription.

But there is so much more an eye exam can provide than just the strength of your glasses. A comprehensive eye exam can show your overall eye health and even expose developing diseases like diabetes. If you’ve never had a comprehensive eye exam before, consider getting one soon.

How can I tell if my eye exams have been comprehensive?

There are a few tell-tale signs that your eye exam is less than comprehensive. Free or discounted clinics are more likely to do non-comprehensive exams. The same goes for eye exams performed at schools or any other setting outside of an actual exam room. Mobile exams like this can’t really bring all the necessary equipment for a full exam.

Eye exams given as part of an overall physical exam are also unlikely to be comprehensive as they are not performed by eye doctors, but by general practitioners, instead.

Why do I need a comprehensive eye exam?

You may wonder why you need a comprehensive eye exam (or any exam at all) as long as your eyes feel fine and your prescription glasses are working well. The answer is that many eye problems can be caught early by an eye exam. Your doctor may recognize the signs of diseases like diabetes, macular degeneration, dry eye or even cataracts long before you begin to show symptoms. An otherwise healthy adult should visit the eye doctor for a full exam every one to two years.

What does a comprehensive eye exam entail?

A comprehensive exam will have the same basics that all eye exams have. These include measuring visual acuity by making you read number and letter patterns from different distances and basic eye alignment tests. But there are a few extra procedures you’ll get during a comprehensive exam.

Color blindness

You will not need a color blindness test every time you see an eye doctor, but if you have never had one before, your doctor may administer one. About 4 percent of the population is color blind to some degree, and most color blind people are men.

Ocular motility

Ocular motility is a fancy word for eye movements. Your doctor will have you place your head against a rest and ask that you follow a moving target with your eyes only. People who have ocular motility problems may have difficulty watching sports, reading, or participating in athletics.

Depth perception

Depth perception tests are not commonly done on an annual basis, but your eye doctor may perform one occasionally or more frequently if necessary. You will wear special glasses and be asked to indicate which shape in a lineup appears closest to you.


This test is similar to a standard visual acuity test only instead of reading numbers out loud, the doctor will dim the lights and then shine a light in your eyes to give an approximation of your prescription. This may not be necessary if you already have an established prescription and have been seeing the same doctor for some time.


This is the quintessential “vision test” where your doctor places a huge device in front or your face and flips between two different lenses, asking you which one provides clearer vision. Even non-comprehensive exams will typically have this procedure.

Slit lamp exam

Using magnification, your doctor will look at your optic nerve and other areas further back in your eye. This allows them to spot the warning signs of different degenerative diseases.

Glaucoma test

A glaucoma test is rarely necessary for younger people, but once you hit middle age, your doctor may begin testing for glaucoma annually.

Pupil dilation

Your doctor may choose to dilate your pupils, which means enlarge them. With dilated pupils, more light gets into your eyes and it is easier for the doctor to see what’s going on. You will be sensitive to light for several hours after the dilating drops have been used, so be sure to bring some sunglasses with you to the exam. 100 percent UV-resistant glasses are the best choice as they will not only dim the light to keep it from annoying you, but they will protect you from the harmful effects of sunlight, as well. You can find a good pair of UV-resistant sunglasses at for cheap. If you need, the glasses can also be fitted to your prescription.

Visual field tests

Vision field tests are quite common during comprehensive eye exams. Your doctor will set you up at a machine and ask you to press a button every time you see something in your peripheral vision. Conditions like glaucoma or certain kinds of brain trauma can affect your peripheral vision.

This all sounds like a lot, but don’t panic. You won’t be sitting in an exam chair all day. Your eye doctor may choose not to perform every test at each visit if you come regularly. Your doctor will determine which tests are the most vital depending on your age, any existing eye conditions and what your insurance is willing to cover. Many of these exams are also very short, taking only a couple minutes each.

Remember that you can always ask your doctor questions. Don’t be shy to ask for an explanation of which tests are being done, whether or not they are all necessary and why your doctor may have chosen not to perform certain tests. You can also ask your doctor for a copy of your prescription. They are required to give you this information.

Once you have an accurate prescription from your doctor, you can shop online for cheap eyeglasses without going through your optometrist. has all the latest styles and lens types to keep your vision sharp. But don’t forget, even with the best glasses available, you still need to keep up with your annual eye exams!