title: Ray vector fields and representation of thin spherocylindrical lenses.
abstract: OBJECTIVE
  To introduce the concept of the ray vector field and apply it to a problem in ophthalmic optics.
  
  
  METHODS
  Matrix and linear algebra are used to relate ray vector fields and a representation of thin spherocylindrical lenses.
  
  
  RESULTS
  Equations were derived relating ray vector fields and a particular coordinate system recommended previously. The method is illustrated with a simple example from ophthalmic optics, namely, addition of spherocylindrical lenses. We also illustrate the method by considering two spherocylinders separated by a distance.
  
  
  CONCLUSIONS
  Ray vector fields are intuitively simple and can be used to solve complex ophthalmic optics problems.
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; D006801:Humans; D008027:Light; D008433:Mathematics; D055095:Optics and Photonics