Studies of Display Symbol Legibility. XXIV. The Relative Legibility of Special Symbols Formed from Different Matrices, and the Legibility of Overprinted Special Symbols

The relative legibility of special symbols constructed from 5 x 7, 5 x 9, 7 x 9 and 7 x 11 dot matrices was determined. The special symbols were shown to one group of operators under nearly optimal viewing conditions. For two other groups of operators, symbol quality was degraded by vertically overprinting one symbol on another. The results indicated that symbol indentification was better for the 7 x 9 matrix than for the 5 x 7 matrix for both good and degraded display conditions. Symbol overprinting greatly impaired the operators' ability to identify special symbols. (Author)
See also AD-850 380.