Target Size, Visibility, and Roadway Performance

Publication Type

Journal Article

LBNL Report Number

LBL-19423

Abstract

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.

Journal

Journal of the Illuminating Engineering Society

Volume

15

Year of Publication

1985

Pagination

167-180

Call Number

LBL-19423