Effects of pixel shape and color, and matrix pixel density of Arabic digital typeface on characters’ legibility

Abstract

Two experiments were conducted to determine: (1) the possibility of fitting Arabic characters on the common rectangular resolutions; (2) the best resolution for Arabic characters to be formed in dot matrix formats; and (3) the possibility of developing a legible low resolution for Arabic characters. The second experiment was a replication of the first one except that some of the Arabic characters that were hard to be identified by the subjects in the first experiment were modified for the second one. Recognition speed, correct response, and preference ranking were dependent variables in both experiments. The independent variables were matrix pixel density, pixel shape, and pixel color. The levels of the matrix pixel density were 5×7, 7×9, 8×8, 9×14, 16×16, and 32×32 resolutions. Square and circular pixels were pixel shape. The pixel colors were red and green. Twenty-four treatment combinations were randomly presented to all subjects, where within subject design was employed to analyze the collected data. In these experiments, fifteen and six subjects exposed to 100 slides of Arabic letters presented on video display terminal for each matrix format. The results indicated that readability was improved significantly with increasing matrix pixel density. The results revealed that Arabic letters were more readable in square matrices (e.g., 8×8) rather than rectangular matrices (e.g., 7×9) in terms of correct responses and performance subjective rating. In addition, readability was significantly improved with square pixel shape. The subjects rated green pixels as more comfortable than the red ones. Finally, this work offers engineers with a legible low-resolution of Arabic typeface, which is essential for designing electronic displays. Relevance to industry Displayed Arabic typeface in visual displays that are ready made in USA or European countries is not well technically prepared. This work presents a digital typeface that will be professionally applicable to be implemented in different types of digital matrix resolutions. In addition, it offers the industrial engineers with a legible low-resolution of Arabic typeface.