title: [Limits of Cognition with Visual Parallax of Stereoscopic Images].
abstract: OBJECTIVE
  Recent advances in three-dimensional (3D) display technology have contributed significantly to society, particularly in the increasing use of stereoscopic characters. For example, 3D text information is utilized in digital signage. However, research on 3D characters is limited and discussion on the safety and comfort of 3D technology is lacking. According to the 3D Consortium Safety Guidelines in Japan, a comfortable visual parallax with 3D images is less than ±1.0°. However, 3D text must be shown in front of its associated content in order for it to be displayed simultaneously with that content.
  
  
  METHODS
  We carried out an experiments to verify the permissive limits of cognition in subjects regarding the parallax of 3D images. In the experiment, 94 subjects aged 18 to 81 viewed a 3D flat Maltess cross image having no depth and projected outward from a screen at a large parallax of 1.0° to 6.0°.
  
  
  RESULTS
  Eighty-six percent of the subjects recognized the 3D flat image even when it protruded at a 2.0° parallax. These subjects viewed the image comfortably and without visual problems.
  
  
  CONCLUSIONS
  This study concludes that people can cognitively recognize a 3D telop at a 2.0° parallax without feeling fatigued.
authors.affiliation: Nagoya University.
authors.forename: Kazuki
authors.initials: K
authors.lastname: Yoshikawa
authors.forename: Takumi
authors.initials: T
authors.lastname: Ohashi
authors.forename: Takehito
authors.initials: T
authors.lastname: Kojima
authors.forename: Yuma
authors.initials: Y
authors.lastname: Honda
authors.forename: Hiromu
authors.initials: H
authors.lastname: Ishio
authors.forename: Masumi
authors.initials: M
authors.lastname: Takada
authors.forename: Masako
authors.initials: M
authors.lastname: Omori
authors.forename: Masaru
authors.initials: M
authors.lastname: Miyao
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D001296:Audiovisual Aids; D003071:Cognition; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D014785:Vision, Ocular; D055815:Young Adult