Effects of Display Failures and Symbol Rotation on Visual Search Using Dot-Matrix Symbols

Abstract

This study was conducted to investigate the effects of display failures and rotation of dot-matrix symbols on visual search performance. The type of display failure (cell, horizontal line, vertical line), failure mode (ON, failures matched the symbols; OFF, failures matched the background), percentage of failures (0, 1, 2, 3, 4%), and rotation angle (0, 70, 105 degrees) were the variables examined. Results showed that displays which exhibit ON cell failures greater than 1% significantly affect search time performance. Cell failures degrade performance more than line failures. Search time and accuracy were best when symbols were oriented upright. The effects of display failures and rotation angle were found to be independent. Implications for display design and suggestions for quantifying the distortion due to rotation are discussed.