The Effect of Rotation on Legibility of Dot-Matrix Characters

Abstract

When dot-matrix characters are rotated, as may be in a moving map display, their dot-matrix patterns are distorted and their legibility is thus affected. In this experiment, 16 subjects performed a random search task in which they were asked to look for a target in a random character pattern. The independent variables were (a) the direction (clockwise or counterclockwise), (b) the angle of stimulus image rotation, and (c) the target character's distance from the center of the screen, which was also the center of rotation. The dependent variables were response time and response correctness. Significant effects were found for the angle of rotation, the target character's distance from the center, and the target character. The results indicate that (a) no angle-dependent mechanism is involved in performing this task and the angle of rotation influences recognition mainly through the distortion of dot-matrix patterns; (b) the target character's radial distance from the center of the screen is the determining factor for search time, while the x and y coordinates of the target contributed to dot-matrix pattern distortion; and (c) the target characters interacted differently with the angle and distance factors to determine the extent of distortion and their legibility. Means to quantify the extent of distortion are discussed and the direction for future research is suggested.

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Document Details

Document Type
Technical Report
Publication Date
Feb 01, 1991
Accession Number
ADA235034

Entities

People

  • Harry L. Snyder
  • Jennie J. Decker
  • Ko Kurokawa

Organizations

  • Human Engineering Laboratory

Tags

Communities of Interest

  • Advanced Electronics
  • C4I
  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Analysis Of Variance
  • Character Recognition
  • Cognition
  • Display Systems
  • Experimental Design
  • Geometry
  • Human Factors Engineering
  • Identification
  • Information Processing
  • Information Science
  • Matrix Displays
  • Perception
  • Psychology
  • Recognition
  • Regression Analysis
  • Statistical Analysis
  • Task Performance And Analysis

Readers

  • Atmospheric Science / Meteorology, specifically Wind Wave Turbulence.
  • Human-Computer Interaction (HCI).