00965567

Component

https://doi.org/10.3141/1844-07

http://scholar.google.com...rman&publication_year=2003

Protan observers have lower spectral sensitivity than color-normal observers at long wavelengths of the visible spectrum. Responses of protan and color-normal subjects to light emitting diode (LED) and incandescent traffic signals of red and yellow nominal color during simulated daytime viewing conditions are described. Reaction times, missed signal percentages, and color-identification accuracy were measured. The results indicate that for protans, detection performance to red LED signals was enhanced when the dominant wavelength was moved toward shorter wavelengths, but this shift also appeared to decrease their ability to correctly identify the signal color. Although the yellow LED signal used in this study provided similar detection performance for protans as a yellow incandescent signal, its dominant wavelength was sufficiently long for it to sometimes be confused with red. In general, the results of this study are consistent with the 1994 recommendations of the Commission Internationale de l'Eclairage for signal colors to be seen by color-normal and protan observers. Nonetheless, neither detection nor color identification for protans approached that of color-normal observers.

This paper appears in Transportation Research Record No. 1844, Traffic Control Devices, Visibility, and Rail-Highway Grade Crossings 2003.

English

p. 52-58

2003

Transportation Research Record

0309085799

Figures (9) ; References (19) ; Tables (3)

Daylight; Detection and identification; Incandescent lamps; Light emitting diodes; Reaction time; Red; Traffic signals; Visually impaired persons; Wavelength; Yellow

Highways; Operations and Traffic Management; Safety and Human Factors; I73: Traffic Control

TRIS, TRB, ATRI

Nov 18 2003 12:00AM

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