The beginning of the Dilated Eye Exam
When your eye doctor starts the dilated eye exam, he or she will instill dilating drops in each eye, which would enlarge your pupils to give the doctor a better view of certain parts of the back of the eye. The drops can take at most 20 to 30 minutes to take effect, but the effects last well beyond the exam, up to several hours.
Enlarging the pupils will allow for more light to enter the eye. When more light can enter the eye, it allows for your eye doctor to have a greater range of visibility within the eye. This provides your eye doctor the ability to use a special magnifying lens to examine the tissues at the back of the eye, including the retina, the macula, and the optic nerve.
Why does an optometrist or ophthalmologist dilate the eyes?
After the Dilated Eye Exam
While people might relax at the eye doctor's office until the effects start to fade, it’s recommended that you invest in a pair of polarized sunglasses. In some cases, your eye doctor may supply you with a free, generally temporary, pair of sunglasses to protect your eyes. While tinted lenses can reduce the amount of light that enters the eyes, during the time your eyesight is extra sensitive, the added protection from polarization is essential.