title: Chromatic aberration in heterocentric astigmatic systems including the eye.
abstract: OBJECTIVE
  There is inconsistency in the literature in the definitions of longitudinal and transverse chromatic aberration, and there appear to be no definitions that make allowance for astigmatism and heterocentricity. The purpose is to propose definitions of longitudinal and transverse chromatic aberration that hold for systems which, like the typical eye, may be heterocentric and astigmatic and to develop the associated optics.
  
  
  METHODS
  Common definitions of longitudinal and transverse chromatic aberration based on Gaussian optics are generalized naturally in terms of linear optics to accommodate heterocentricity and astigmatism.
  
  
  CONCLUSIONS
  The definitions offered here apply to systems in general, including the visual optical system of the eye, and hold for homocentric stigmatic systems in particular. Care is advocated in the use of the terms longitudinal and transverse chromatic aberration.
authors.affiliation: Department of Optometry, University of Johannesburg, Johannesburg, South Africa. wharris@uj.ac.za
authors.forename: William F
authors.initials: WF
authors.lastname: Harris
authors.forename: Tanya
authors.initials: T
authors.lastname: Evans
mesh_terms: D001251:Astigmatism / Q000503:physiopathology*; D003118:Color Perception / Q000502:physiology*; D005123:Eye / Q000503:physiopathology*; D006801:Humans; D055620:Optical Phenomena