Main Article Content
Signs should produce useful visual information to road and sidewalk users without creating undue glare or visual distraction. In order to assist in navigation and wayfinding, signs must be sufficiently conspicuous. For this reason their brightnesses are often higher than the surrounding visual environment. However, if the brightness becomes too high, the sign risks contributing to visual discomfort. Several published recommendations for limiting sign brightness include limits on the maximum illuminance from the sign (in lux). There is evidence, however, that the maximum luminance of a light source can also influence visual comfort. To investigate the potential role of maximum luminance, a pilot study was carried out to assess visual responses to sign panels producing the same illuminance but differing in luminance.
Bullough, J.D., & Sweater Hickcox K. (2012). Interactions among light source luminance, illuminance and size on discomfort glare. Society of Automotive Engineers International Journal of Passenger Cars - Mechanical Systems 5(1), 199-202.
Cornog, D.Y., & Rose F.C. (1967). Legibility of alphanumeric characters and other symbols, II: A reference handbook. Washington, DC: National Bureau of Standards.
De Boer, J. (1967). Public lighting. Eindhoven, Netherlands: Philips Technical Library.
Freyssinier, J.P., Narendran, N., & Bullough, J.D. (2006). Luminance requirements for lighted signage. Proceedings of Sixth International Conference on Solid State Lighting 6337, 63371M.
Garvey, P.M. (2005). On-premise commercial sign lighting and light pollution. Leukos 1(3), 7-18.
Garvey, P.M. (2015). On-premise electronic message center lighting levels: Phase 1, phase 2. Bristol, PA: United States Sign Council Foundation.
Garvey, P.M., & Klena, M.J. (2017). Standard luminance levels of on-premise signs. Bristol, PA: United States Sign Council Foundation.
International Sign Association. (2016). Night-time brightness level recommendations for on-premise electronic message centers. Alexandria, VA: International Sign Association.
Lewin, I. (2008). Digital billboard recommendations and comparisons to conventional billboards. Scottsdale, AZ: Lighting Sciences, Inc.
McGuigan, F.J. 1990. Experimental Psychology. Englewood Cliffs, NJ: Prentice Hall.