Changes in Accommodative Function of Young Adults in their Twenties following Smartphone Use

스마트폰 사용에 따른 20대 성인의 조절기능 변화

  • Park, Mijung (Dept. of Optometry, Seoul National University of Science and Technology) ;
  • Ahn, Young Joo (Dept. of Optometry, Seoul National University of Science and Technology) ;
  • Kim, Soo Jung (Dept. of Optometry, Seoul National University of Science and Technology) ;
  • You, Jiyoung (Dept. of Optometry, Seoul National University of Science and Technology) ;
  • Park, Kyung Eun (Dept. of Optometry, Seoul National University of Science and Technology) ;
  • Kim, So Ra (Dept. of Optometry, Seoul National University of Science and Technology)
  • 박미정 (서울과학기술대학교 안경광학과) ;
  • 안영주 (서울과학기술대학교 안경광학과) ;
  • 김수정 (서울과학기술대학교 안경광학과) ;
  • 유지영 (서울과학기술대학교 안경광학과) ;
  • 박경은 (서울과학기술대학교 안경광학과) ;
  • 김소라 (서울과학기술대학교 안경광학과)
  • Received : 2014.05.12
  • Accepted : 2014.06.18
  • Published : 2014.06.30


Purpose: The present study was conducted to investigate whether near work with smartphone could induce the change of accommodative function. Methods: Total 63 subjects(26 male and 37 female) in their 20s were firstly examined their visual functions related to accommodation and uncorrected spherical equivalent power as the control. After that, the subjects were asked to read a book for 30 min and sequentially watch a movie on smartphone for the same time after 30 min-break under the indoor light or as it was in the reverse order to avoid time-ordered effect. Their accommodative functions, 1) accommodative amplitude, 2) accommodative facility, 3) relative positive/negative accommodation, and 4) accommodative lag and their uncorrected spherical equivalent power were examined again following each task and compared with the control values. Results: The monocular accommodative amplitude was significantly decreased after smartphone watching compared with it after reading. The monocular and binocular accommodative facilities were tended to reduce after smartphone watching and book reading but were not significantly different. Neither significant change in positive relative accommodation was determined after smartphone watching nor book reading. Negative relative accommodation after smartphone watching was almost unchanged unlike reading a book. The accommodative lag after smartphone work was significantly higher than after book reading. Conclusions: The near work with a smartphone for 30 min induced the change of some accommodative functions, which was significantly greater than when reading under the same working environment.


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