What color combinations provide the best levels of contrast under day, night, and low light conditions?
” Contrast refers to the brightness difference between letters or symbols and their background. In general, the greater the contrast, the easier it will be to see and to read text on printed materials and on signs. The Access Board issued a Technical Assistance Manual in October 1992, entitled Buses, Vans, and Systems, which recommended that signage characters contrast with the background by 70 percent[1]. Many of the other documents reviewed indicated the use of yellow characters on a black background as a good choice. In at least one case the research suggested that white on deep navy blue is the preferred combination for people with visual impairments. LED/LCD technology, however, is not yet advanced enough to present a full range of colors that can be seen under all lighting conditions of interest. Currently only red LEDs are bright enough to be seen outside in full sunlight. Other colors (yellow, green, blue) are available and in use for inside (vehicle or terminal) or low ambient
