Rearward Vision, Driver Confidence, and Discomfort Glare Using an Electrochromic Rearview Mirror

摘要

Electrochromic rearview mirrors can provide continuous levels of reflectivity and unobtrusive, automatic control. The availability of the technology has increased the importance of understanding how to select the best level of reflectivity for a given set of lighting conditions. For night driving with glare from following headlights, the best reflectivity level will always depend on a tradeoff among several variables. The study was designed to help clarify what variables are important and how they should be quantified. Twenty subjects, 10 younger and 10 older, performed a number of visual tasks while viewing stimuli through an electrochromic rearview mirror. Results showed that: (1) visual performance decreased with decreasing reflectivity approximately as a linear function of log reflectivity, (2) subjects' confidence consistently underestimated their actual performance but otherwise accurately reflected the effect of reflectivity on performance, and (3) the effect of reflectivity on discomfort glare is not fully predicted by its effect on illumination at the subject's eye point.