Analysis of roadway tasks in terms of the CIE 19/2 visibility parameters has beensrestricted to calculation of VL at a fixed distance because there has been no way to adjust forsthe change of apparent size with distance. We use a rough ft of the absolute threshold contrastsdata as a function of luminance and size to allow the computation of VL as a function ofsdistance. Sample VL versus distance and VL versus time calculations are presented. Aspreliminary estimate of detection probability as a function of time is compared to Gallagherssmeasured results to see how current detection models compare to real results.
BT - Journal of the Illuminating Engineering Society C1 -Lighting Systems Group
C2 - LBL-19423 CN - LBL-19423 LA - eng M1 - 1 N2 -Analysis of roadway tasks in terms of the CIE 19/2 visibility parameters has beensrestricted to calculation of VL at a fixed distance because there has been no way to adjust forsthe change of apparent size with distance. We use a rough ft of the absolute threshold contrastsdata as a function of luminance and size to allow the computation of VL as a function ofsdistance. Sample VL versus distance and VL versus time calculations are presented. Aspreliminary estimate of detection probability as a function of time is compared to Gallagherssmeasured results to see how current detection models compare to real results.
PY - 1985 SP - 167 EP - 180 T2 - Journal of the Illuminating Engineering Society TI - Target Size, Visibility, and Roadway Performance VL - 15 ER -