Longitudinal chromatic aberration of the human eye and wavelength in focus.

: The wavelength in focus on the retina was determined for 14 observers from measurements of the longitudinal chromatic aberration of the eye. Measurements were made at two viewing distances: 3 m and 40 cm. The results show a large amount of individual variability for the wavelength in focus at each distance. The range of values at 3 m was 457 to 593 nm with a mean of 518 nm, and 375 to 548 nm with a mean of 468 nm at 40 cm. The chromatic aberration measured at 3 m is the same as previously reported data by other investigators for distant viewing. The average results of this study indicate very little difference for the chromatic aberration measured at near compared to distant viewing but, again, considerable individual variability exists.