title: Characteristics of head-mounted displays and their effects on simulator sickness.
abstract: OBJECTIVE
  We examined the effects of several display characteristics of head-mounted displays (HMDs) on simulator sickness (SS).
  
  
  BACKGROUND
  Technological limitations, such as display delay and reduced field of view (FOV), affect perception when using an HMD and are often thought to be related to SS. Few studies have examined the relationship between FOV and geometric FOV (image scale factor) or how HMD characteristics may interact.
  
  
  METHODS
  Participants made active head movements to locate objects when viewing a live video via an HMD.
  
  
  RESULTS
  Compared with no added delay, an additional 200 ms of display delay did not result in increased SS, as measured by the Simulator Sickness Questionnaire. Furthermore, an effect of image scale factor on SS was not revealed. However, SS was greater when peripheral vision was occluded than when it was not. Peripheral vision moderated the effects of image scale factor and delay on head movement velocity.
  
  
  CONCLUSIONS
  Occluding peripheral vision may subject HMD users to the potential detrimental consequences of HMD characteristics more than when peripheral vision of the external environment is available, resulting in more SS. Future research should investigate to what extent peripheral vision can be occluded without increasing SS and without sacrificing realism and presence.
  
  
  CONCLUSIONS
  To reduce the occurrence of SS, a degree of peripheral vision of the external world should be provided. Furthermore, users and designers should be aware that head movement behavior may be affected by HMD characteristics.
authors.affiliation: Psychology Department, Clemson University, Clemson, SC 29634, USA. jdmoss25@gmail.com
authors.forename: Jason D
authors.initials: JD
authors.lastname: Moss
authors.forename: Eric R
authors.initials: ER
authors.lastname: Muth
mesh_terms: D000293:Adolescent; D003198:Computer Simulation; D003626:Data Display; D003867:Depth Perception / Q000502:physiology; D005260:Female; D019416:Head Movements / Q000502:physiology*; D006801:Humans; D008297:Male; D009041:Motion Sickness / Q000503:physiopathology; D013647:Task Performance and Analysis; D055815:Young Adult