A.J. Holick, S.T. Chrysler, P.J. Carlson
The Clearview font was developed for traffic signs as the result of a program to increase the legibility and ease of recognition of positive contrasts sign legends while reducing the effects of halation (or overglow). Halation is a particular problem for older drivers and drivers with contrast sensitivity when letters use high brightness retroreflective materials.
One component of the program was to identify ways to create a more effective typeface than the E-modified font used for destination legends on freeway guide signs. A second component was to compare the ease of recognition of mixed-case displays in lieu of all capital letter displays (Series D), and to learn if a mixed-case display would need to be larger than the comparable all-capital display for improved legibility and ease of recognition. When allowing a viewer to read the footprint of the world displayed in upper and lowercase letters similar to printed text, there is an increase in accuracy, viewing distance, and reaction time.
Evaluation of Clearview Font on Negative Contrast Signs
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