The Older Driver — A Challenge to the Design of Automotive Electronic Displays

Older drivers present unique challenges to the display designer. Approximately 30 percent of all drivers in the U.S. are over 50 years of age. Visual impairment, e.g., presbyopia, begins after 40. After age 55, approximately 91 percent of the population use bifocals. Unfortunately, bifocals with significant add power create zones of decreased acuity in the critical instrument panel viewing distances of 500–800 mm. In this paper, the demands for vision in driving are related to the special visual disabilities associated with the older driver, such as increased sensitivity to glare, high contrast ratio blurring of electronic displays and increased time for target recognition. A computer legibility model is presented to relate the principal factors in design, namely character height and width, viewing distance, contrast ratio and background luminance with legibility impairment associated with various age groups. Implications of model predictions to display design are discussed.