Why Do Swim Goggles Correct My Vision?
AUG 17, 2015
I am curious as to why my non-prescription swim goggles correct my underwater vision?
Light travels in straight lines until it comes in contact with a different media. For example, when light travels through air until it strikes your eyeglasses and is bent or focused (also called refraction), creating a clear image for you to see. Each media has a relative number that relates to the transmissibility of light, and it is called the index of refraction. The index of refraction of air is 1.0. Water has an index of refraction of 1.3. Your swim goggles also have an index of refraction, but I don’t know what the index of refraction of your specific swim goggles might be. Suffice it to say, the index of refraction of your goggles and of the water work out well for your specific degree of focusing error (nearsightedness or farsightedness). This lucky situation you have experienced would not be true for everyone. I suggest you ask your ophthalmologist for further explanation of your specific situation.