Undilated pupils can limit the view inside
By making the pupil larger, we can see more
Dilation of the pupil refers to the technique of instilling eyedrops which temporarily make your pupils larger. This gives your doctor an opportunity to see more of your retina when he looks into your eye to examine its health. It’s a lot like looking into a keyhole to see what’s inside a room; the bigger the keyhole, the more you can see.
A commonly noticed effect of the drops is the temporary reduction in focusing ability to see things at near clearly. For some younger patients this effect is an advantage to the doctor who can utilize it to determine a more accurate prescription for the patient. The blurriness at near gradually reduces quickly and the ability to focus at near again should return within one hour.
Dilation begins to wear off in 1/2 hour and is near normal after 4 hours. During this time, you may receive some special temporary sunglasses to wear to protect you from bright light. Your vision examination is a lot more than just a test for glasses. Exams with routine dilation of your eyes are more common now than in the past. This helps assure that you receive the highest quality vision care that is available.