title: The physiology of scotopic vision, contrast vision, color vision, and circadian rhythmicity: can these parameters be influenced by blue-light-filter lenses?
abstract: OBJECTIVE
  Evaluation of the potential effects of blue-light-filter lenses on sensory and physiologic factors.
  
  
  METHODS
  Scientific knowledge on circadian rhythm and scotopic vision will be summarized and potential effects of blue-light-filtering lenses on these parameters will be assessed on a theoretical basis. Clinically relevant studies will also be discussed.
  
  
  RESULTS
  As far as circadian rhythm is concerned, it should be noted that at 480 nm, i.e., at maximum visual excitation of the light intensity to be measured, blue-light-filtering lenses show roughly the same transmission characteristics as the human crystalline lens. Interference with the circadian rhythm due to blue-light-filtering lenses, therefore, is not to be expected. Regarding scotopic vision, no clinically significant impairment is to be expected from blue-light-filter lenses because maximum excitation in scotopic light reception occurs at 507 nm whereas the light transmission of blue-light-filter lenses is 85%--this is higher than that of a child's crystalline lens. Numerous clinical studies corroborate these findings and demonstrate that color vision and contrast vision are not compromised by blue-light-filter intraocular lenses.
  
  
  CONCLUSIONS
  Based on current findings, we do not anticipate blue-light-filter lenses to have a clinically significant effect on physiologic parameters such as scotopic vision, color, and contrast vision or the circadian rhythm.
authors.affiliation: Augenklinik, Klinikum Karlsruhe, Moltkestrasse 90, Karlsruhe, Germany. 106020.560@compuserve.com
authors.forename: Albert J
authors.initials: AJ
authors.lastname: Augustin
mesh_terms: D002648:Child; D002940:Circadian Rhythm / Q000502:physiology*; D003116:Color; D055253:Color Vision / Q000502:physiology*; D015350:Contrast Sensitivity / Q000502:physiology*; D005374:Filtration / Q000295:instrumentation*; D006801:Humans; D007908:Lens, Crystalline / Q000502:physiology; D007909:Lenses; D008027:Light; D055254:Night Vision / Q000502:physiology*