The Legibility of Type As a Function of Reflectance of Background under Low Illumination

Abstract

The legibility of lower case type as a function of illumination level, reflectance of background, and type size was measured by means of speed and accuracy scores on a letter cross out test. Simulated red cockpit illumination was used, covering the range from 0.014 to 0.129 foot-candles. Red light reflectance of background was varied from 0.26 to 0.87. Type sizes were 6 and 8 point. Scores fell off at an accelerated rate with decreasing illumination and background reflectance, and were lower under all conditions for 6 than for 8 point type. The specific application of these data to chart design will be covered in a subsequent report.

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Document Details

Document Type
Technical Report
Publication Date
Jun 01, 1952
Accession Number
ADB220005

Entities

People

  • John A. Hanson
  • Joseph W. Wulfeck
  • Mason N. Crook

Organizations

  • Tufts University

Tags

Communities of Interest

  • C4I

DTIC Thesaurus Topics

  • Accuracy
  • Air Force
  • Brightness
  • Candles
  • Contrast
  • Control Panels
  • Elevation
  • Government Procurement
  • Illumination
  • Intensity
  • Light Sources
  • Materials
  • Optical Properties
  • Psychology
  • Reflectance
  • Surface Properties
  • White Light

Readers

  • Business Analytics
  • Human-Computer Interaction (HCI).
  • Thin Film Deposition Science.