The Effects of Letter Size, Case, and Generation Method on CRT Display Search Time

The effects of letter size, case, and generation method were studied in a task of searching for a common five-letter word in a CRT display. Symbol sizes of 0.12, 0.14, and 0.16 in. were evaluated. Words were composed of all uppercase or all lowercase letters. Two symbol generation methods-letters drawn by means of continuous strokes and by means of a seven-wide-by-nine-high pattern of dots in a fixed matrix-were investigated. The results indicated that for both methods of symbol generation, uppercase words were searched 13% faster than lowercase words. No significant differences were found due to symbol generation method or letter size.