On the readability and useful visual field of scrolling text

2006 Fiscal Year Final Research Report Summary

• Project/Area Number: 17530524
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Experimental psychology
• Research Institution: University of Tsukuba
• Principal Investigator: KIKUCHI Tadashi University of Tsukuba, Graduate School of Comprehensive Human Sciences, Professor, 大学院人間総合科学研究科, 教授 (80161420)
• Co-Investigator(Kenkyū-buntansha): SHIINA Ken University of Tsukuba, Graduate School of Library Information and Media Studies, Professor, 大学院図書館情報メディア研究科, 教授 (70093599) ; HIROMI Morita University of Tsukuba, Graduate School of Library Information and Media Studies, Assistant Professor, 大学院図書館情報メディア研究科, 講師 (00359580)
• Project Period (FY): 2005 – 2006
• Keywords: scrolling text / reading / useful visual field

Research Abstract

Scrolling text refers to the media in which text is scrolling from right to left in a limited space. We explored the properties of presentation to read scrolling text comfortably. The primary findings could be summarized as follows.
1) We made a text scroll in a viewing window. The width of the window was varied from 1 to 15 characters, and observers were asked to adjust a scrolling rate to read the text comfortably. Optimal scrolling rate is increased rapidly with the increase of the window width up to 5 characters. Then the rate of increase gradually reduced and almost leveled off up to 15 characters. The scrolling rate of devices placed on the streets was found two times slower than the present results.
2) We manipulated the number of characters (2,5,and 15) and scrolling rate (based on the preliminary experiments, optimal, two times faster and two times slower than the optimal rate). Observers were asked to evaluate their impressions according to 14 items by using a 7-point scale. The 5 and 15 characters-number conditions impressed the observers similarly. Moreover, in all characters-number conditions, faster presentations were evaluated as "hard to apprehend" and slower presentations as "irritating".
3) We briefly presented a Hiragana character above or below the left, center, or right corner of the viewing window. Observers were asked to ignore or discriminate the Hiragana character, while adjusting scrolling rate to read the text comfortably. When the Hiragana character was presented above or below the right corner of the viewing window, scrolling rate was significantly slower than when the Hiragana character was presented at the other positions. This indicates that useful visual field is distributed widely on the right side of the viewing window when observers are reading a scrolling text.