Abstract: A method may include displaying, to a user, a first color in a first area and a second color in a second area, where (1) the second color has a longer wavelength than the first color and (2) the first and second color have an expected longitudinal chromatic aberration for a human eye. The method may also include receiving, from the user, an indication of whether the user perceives (1) the first area as being clearer than the second area or (2) the second area as being clearer than the first area. The method may further include determining, based on the indication of the user and the expected longitudinal chromatic aberration, information about a refractive error of the user's vision. Various other methods, systems, and devices are also disclosed.