title: Nonprescription tinted eyewear optical accuracy study.
abstract: BACKGROUND
  Nonprescription tinted eyewear, commonly referred to as noncorrective sunglasses or plano sun eyewear, often induce measurable amounts of prismatic deviation. With high-wrap eyewear this effect becomes more pronounced. The purpose of this project was to assess the amount of horizontal and vertical prismatic deviation induced by some popular premium plano sun eyewear intended for use by athletes.
  
  
  METHODS
  Prismatic deviations for two identical pairs of high-wrap, steep base curve, plano sun eyewear from each of six prominent national brands were measured in both primary gaze and along a peripheral line of sight 30 degrees to the right of straight-ahead.
  
  
  RESULTS
  Most of the eyewear induced base-out and base-down prism in each lens in primary gaze. All eyewear induced base-in prism with temporal gaze and base-out prism with nasal gaze at 30 degrees laterally. Most eyewear induced base-down prism with lateral gaze as well.
  
  
  CONCLUSIONS
  Plano sun eyewear is often purchased for use in bright environments during visually demanding sports, such as golf, baseball, and volleyball. It is well-documented that athletes possess superior visual function as compared to nonathletes or lesser-level athletes. Further studies are indicated to determine the impact of this prism on the average wearer and the elite athlete.
authors.affiliation: Pacific University College of Optometry, Forest Grove, Oregon 97116, USA. cooper@pacific.edu
authors.forename: S C
authors.initials: SC
authors.lastname: Cooper
authors.forename: J A
authors.initials: JA
authors.lastname: Smith
authors.forename: M
authors.initials: M
authors.lastname: Katz
authors.forename: J
authors.initials: J
authors.lastname: Preston
mesh_terms: D003290:Convergence, Ocular; D003867:Depth Perception; D005135:Eye Protective Devices / Q000592:standards*; D019466:Glare; D006801:Humans; D009907:Optometry / Q000379:methods / Q000592:standards; D015203:Reproducibility of Results; D015348:Vision, Binocular; D014792:Visual Acuity