Eye experts
Master Sgt. Preston Kash, a 22nd Air Force Detachment 1 flight engineer, has his vision capability tested with a phoropter during an eye examination June 30, 2014, at Little Rock Air Force Base, Ark. Examples of things evaluated during a routine eye exam include eye pressure, depth perception, eye muscle movement and the condition of the retinas. (U.S. Air Force photo by Airman 1st Class Harry Brexel)