This report describes two experiments examining the effects of various CRT screen treatments on reflectance and user performance. In the first experiment, physical measurements were taken of the light emitted and reflected from the screen of a popular video terminal. Measurements were taken for both normal and reverse polarity when the tube face was bare. Similarly, measurements were taken when the screen was covered with either a micromesh or plastic filter. Measurements were taken at the center and upper-right corner of the screen. At the center point there were no significant differences in reflectance due to polarity, but differences due to screen filters were significant. (The micromesh filter was particularly effective in reducing reflectance.) For the corner point there were no significant differences in reflectance due to either polarity or filter. The second experiment was a human performance test concerning the same six treatment conditions and terminal as were used in the first experiment. Six university students were asked to count how often the character-pair "3W" occurred within a block of text shown on the screen. Except for normal polarity leading to shorter search times, neither the filter nor polarity changes had statistically significant effects on search times or errors. There was, however, a tendency for the plastic filter to lead to poorer performance (longer search times, more errors).

  • Corporate Authors:

    University of Michigan Transportation Research Institute

    2901 Baxter Road
    Ann Arbor, MI  United States  48109-2150
  • Authors:
    • Miller, D E
    • Peterson, E A
    • Green, P
  • Publication Date: 1984-5

Media Info

  • Features: Appendices; Figures; References; Tables;
  • Pagination: 36 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00392228
  • Record Type: Publication
  • Source Agency: National Highway Traffic Safety Administration
  • Report/Paper Numbers: UMTRI-84-8 Final Rpt., HS-037 321
  • Files: HSL, TRIS, USDOT
  • Created Date: Jan 30 1985 12:00AM