DOI QR코드

DOI QR Code

저휘도 환경에서 태블릿 PC를 이용한 장시간 독서시 문자대비가 가독성과 피로감에 미치는 영향

Effect of Luminance Contrast Ratio of Character on Readability and Visual Fatigue during Long-term Reading Using Tablet PC in Low Luminance Environment

  • 투고 : 2019.03.14
  • 심사 : 2019.05.09
  • 발행 : 2019.05.30

초록

This study examines the effect of luminance contrast ratio of character on readability and visual fatigue during an hour-long reading session while using a tablet PC in ambient environments having low luminance limited to $25cd/m^2$. Experiments were conducted with four patterns of the tablet's luminance contrast ratio of characters, namely 1:2.5, 1:4.5, 1:6.5, and 1:8.5, in low ambient luminance of $9cd/m^2$ and $25cd/m^2$. The obtained results show that the characters can be easily read at the luminance contrast ratio of character of 1:8.5 under surface luminance of $25cd/m^2$. Visual fatigue was evaluated through a subjective survey of symptoms. Physical, psychological, and visual fatigue were observed at a surface luminance of $9cd/m^2$, whereas solely visual fatigue was felt at a surface luminance of $25cd/m^2$. By assessing the physical fatigue using the value, it has been found that smaller the luminance contrast ratio of character, greater is the CFF variation rate. Furthermore, readability is poor and visual fatigue can be observed when the surface luminance is lower than the ambient luminance. However, readability can be improved by increasing the luminance contrast ratio of character to a value of 1:8.5. Thus, in low luminance environments, luminance contrast ratio of characters can affect readability and fatigue. Consider providing the full form of "CFF" so that the acronym can be used unambiguously throughout the manuscript.

키워드

참고문헌

  1. Architectural Institute of Japan (2012). Survey and Analysis Methods for Architecture and Urban Planning. Inoueshoin Co. Ltd., 124.(ISBN978-4-7530-1754-6)
  2. Architectural Institute of Japan (2015). Psychology and Environment Designer Practice of Sense and Perception. Gihodo Shuppan Co. Ltd., 33-52.(ISBN978-4-7655-2583-1)
  3. Benedetto, S., Drai-Zerbib, V., Pedrotti, M., Tissier, G., & Baccino, T. (2013). E-readers and visual fatigue. PloS one, 8(12), e83676. https://doi.org/10.1371/journal.pone.0083676
  4. Chang, P. C., Chou, S. Y., & Shieh, K. K. (2013). Reading performance and visual fatigue when using electronic paper displays in long-duration reading tasks under various lighting conditions. Displays, 34(3), 208-214. https://doi.org/10.1016/j.displa.2013.06.001
  5. Hashimoto, K. (1981). Measurement of general fatigue. Japan Ergonomics Society, 17(3), 107-113. https://doi.org/10.5100/jje.17.107
  6. Hosokawa, T., Mikami, K., & Saito, K. (1997). Basic study of the portable fatigue meter: effects of illumination, distance from eyes and age. Ergonomics, 40(9), 887-894. https://doi.org/10.1080/001401397187720
  7. Housing Research Institute Research Report (2010). Illuminance design method using brightness (brightness scale value) felt by people, "Flexible Lighting" Creating a pleasant and pleasant "light place" created by three steps. Asahi Kasei Homes Co., Ltd., p9.
  8. Kang, Y. Y., Wang, M. J. J., & Lin, R. (2009). Usability evaluation of e-books. Displays, 30(2), 49-52. https://doi.org/10.1016/j.displa.2008.12.002
  9. Kim, Y., & Ha, K. (2014). Comparison of Characteristics and Usage Patterns of Notebook PC and Tablet PC Users, KISDI STAT Report, 14-08-02, 11-17.
  10. Lee, D. S., Ko, Y. H., Shen, I. H., & Chao, C. Y. (2011). Effect of light source, ambient illumination, character size and interline spacing on visual performance and visual fatigue with electronic paper displays. Displays, 32(1), 1-7. https://doi.org/10.1016/j.displa.2010.09.001
  11. Lin, H., Wu, F. G., & Cheng, Y. Y. (2013). Legibility and visual fatigue affected by text direction, screen size and character size on color LCD e-reader. Displays, 34(1), 49-58. https://doi.org/10.1016/j.displa.2012.11.006
  12. Lin, P. H., Lin, Y. T., Hwang, S. L., Jeng, S. C., & Liao, C. C. (2008a). Effects of anti-glare surface treatment, ambient illumination and bending curvature on legibility and visual fatigue of electronic papers. Displays, 29(1), 25-32. https://doi.org/10.1016/j.displa.2007.06.009
  13. Lin, Y. H., Chen, C. Y., Lu, S. Y., & Lin, Y. C. (2008b). Visual fatigue during VDT work: Effects of time-based and environment-based conditions. Displays, 29(5), 487-492. https://doi.org/10.1016/j.displa.2008.04.003
  14. Mackenzie, I. Scott (2013). Human-Computer Interaction. Morgan Kaufmann Publishers An Imprint of Elsevier, 171-173, ISBN978-0-12-405865-1
  15. Murata, K., Araki, S., Kawakami, N., Saito, Y., & Hino, E. (1991). Central nervous system effects and visual fatigue in VDT workers. International archives of occupational and environmental health, 63(2), 109-113. https://doi.org/10.1007/BF00379073
  16. Osgood, C.E., Suci, G.J. & Tannenbaum, P.H. (1957). The Measurement of Meaning. Illinois Press.
  17. Rovamo, J., Virsu, V., & Näsänen, R. (1978). Cortical magnification factor predicts the photopic contrast sensitivity of peripheral vision. Nature, 271(5640), 54. https://doi.org/10.1038/271054a0
  18. Sakai, K. (2002). Japan Industrial Hygienics Association Industrial Fatigue Research Society Revision work on "subjective symptoms", labor science, 57(5), 295-298.
  19. Shen, I. H., Shieh, K. K., Chao, C. Y., & Lee, D. S. (2009). Lighting, font style, and polarity on visual performance and visual fatigue with electronic paper displays. Displays, 30(2), 53-58. https://doi.org/10.1016/j.displa.2008.12.001
  20. Shieh, K. K. (2000). Effects of reflection and polarity on LCD viewing distance. International Journal of Industrial Ergonomics, 25(3), 275-282. https://doi.org/10.1016/S0169-8141(99)00018-9
  21. Shieh, K. K., & Lee, D. S. (2007). Preferred viewing distance and screen angle of electronic paper displays. Applied Ergonomics, 38(5), 601-608. https://doi.org/10.1016/j.apergo.2006.06.008
  22. Shigematsu, K. (2005). Before that day, Kindle ver., Language: Japanese, ASIN:B009A49AU8, Publisher: Bungeishunju Ltd.
  23. Simonson, E. R. N. S. T., Enzer, N. O. R. B. E. R. T., & Blankstein, S. S. (1941). The influence of age on the fusion frequency of flicker. Journal of Experimental Psychology, 29(3), 252-255. https://doi.org/10.1037/h0056872
  24. Tachi N. (2002). Proposal and revision work progress of the new version "subjective symptoms". Labor Science, 57 (5), 299-304.
  25. Takeda, M. (1997). A study on changes of CFF values due to differences in task-proposing method. Japan Ergonomics Society, 33(6), 385-392. https://doi.org/10.5100/jje.33.385
  26. Watanuki, T., Takahashi, H., & Irikura, T. (2015). Brightness Perception Through out the Entire Visual Field. The Illuminating Engineering Institute of Japan, 99(5), 258-262. https://doi.org/10.2150/jieij.99.258
  27. Yu, H., Akita, T., Koga, T., & Sano, N. (2018). Effect of character contrast ratio of tablet PC and ambient device luminance ratio on readability in low ambient illuminance. Displays, 52(2), 46-54. https://doi.org/10.1016/j.displa.2018.03.002