title: An exploration of the initial effects of stereoscopic displays on optometric parameters.
abstract: OBJECTIVE
  To compare the effect on optometric variables of reading text presented in 2-D and 3-D on two types of stereoscopic display.
  
  
  METHODS
  This study measured changes in binocular visual acuity, fixation disparity, aligning prism, heterophoria, horizontal fusional reserves, prism facility and accommodation responses for near of subjects after completing ten consecutive reading tasks of 1 minute each. The tasks consisted of reading words on a polarized two-view (n = 39) and an auto-stereoscopic lenticular nine-view display (n = 19) with the text presented without or with stereoscopic disparity at 3 m. Performance was assessed by measuring reading speed and symptoms were rated by the Convergence Insufficiency Symptom Survey (CISS) questionnaire.
  
  
  RESULTS
  With both types of display, CISS scores at least doubled immediately after subjects viewed the 3-D text image in an extreme stereoscopic condition compared to the 2-D condition (p < 0.001), while the mean reading speed slowed (p < 0.001). Mean changes in optometric test variables were not clinically or statistically significant (p values > 0.05). After the 3-D task one participant showed consistent clinically meaningful decreases in convergent fusional break and recovery points for both displays.
  
  
  CONCLUSIONS
  When healthy adult subjects with normal binocular vision viewed text images at 3 m in extreme 3-D display settings for a short period of time there were no clinically significant mean changes in optometric test variables compared with 2-D viewing.
authors.affiliation: Department of Optometry, Utrecht University of Applied Science, Hogeschool Utrecht, Utrecht, the Netherlands.
authors.forename: Marten F
authors.initials: MF
authors.lastname: Fortuin
authors.forename: Marc T
authors.initials: MT
authors.lastname: Lambooij
authors.forename: Wijnand A
authors.initials: WA
authors.lastname: Ijsselsteijn
authors.forename: Ingrid
authors.initials: I
authors.lastname: Heynderickx
authors.forename: David F
authors.initials: DF
authors.lastname: Edgar
authors.forename: Bruce J W
authors.initials: BJ
authors.lastname: Evans
mesh_terms: D000065:Accommodation, Ocular / Q000502:physiology; D000293:Adolescent; D000328:Adult; D003626:Data Display; D003867:Depth Perception / Q000502:physiology*; D005260:Female; D005403:Fixation, Ocular / Q000502:physiology; D006801:Humans; D021621:Imaging, Three-Dimensional; D008297:Male; D010775:Photic Stimulation / Q000379:methods; D011897:Random Allocation; D011932:Reading; D013690:Television; D015348:Vision, Binocular / Q000502:physiology; D014792:Visual Acuity / Q000502:physiology; D055815:Young Adult