title: Ray vector fields, prentice's equation, and Fourier representation of spherocylindrical lenses.
abstract: OBJECTIVE
  To illustrate how the concept of ray vector fields can be used to demonstrate the elementary properties of thin lenses.
  
  
  METHODS
  Principles of matrix algebra are used.
  
  
  RESULTS
  Using simple geometry we give a generalization of Prentice's rule to include thick astigmatic lenses. Starting from the ray vector fields we show the connection between various representations of spherocylindrical lenses (Fourier representation, expansion in terms of the cross-cylinders). We suggest two clinical areas to which these concepts can be applied.
authors.affiliation: School of Optometry, University of Missouri-St. Louis, USA.
authors.forename: V
authors.initials: V
authors.lastname: Lakshminarayanan
authors.forename: S
authors.initials: S
authors.lastname: Varadharajan
mesh_terms: D005139:Eyeglasses; D005583:Fourier Analysis; D006801:Humans; D008027:Light; D055095:Optics and Photonics