To obtain a better view of the eye’s internal structures, your eye doctor instills dilating drops to enlarge your pupils. Dilating drops usually take about 20 to 30 minutes to start working. When your pupils are dilated, you will be sensitive to light (because more light is getting into your eye) and you may notice difficulty focusing on objects up close. These effects can last for up to several hours, depending on the strength of the drop used.
Once the drops have taken effect, your eye doctor will use various instruments to look inside your eyes. You should bring sunglasses with you to your eye exam, to minimize glare and light sensitivity on the way home. If you forget to bring sunglasses, the staff usually will give you a disposable pair.
Pupil dilation is very important for people with risk factors for eye disease, because it allows for the most thorough evaluation of the health of the inside of your eyes.