Luminance Contrast-Based Analysis of Characteristics in Automotive Headlight Visibility Performance
For travelers driving on unlit roads at night, the headlights of their vehicles are the only means for them to secure visibility. Although nighttime visibility on the road gets determined by luminance contrast, visibility performance did a relationship between the obstacle and its backdrop (road surface). However, the current practice in car headlight visibility performance evaluation is based on the luminous intensity of headlight lamps and illumination of road surface. Such practice can be inappropriate from a visibility point of view where visibility indicates abilities to perceive an object ahead on the road. This study aimed at evaluating the appropriateness of current evaluation method. To that end, the study measured the illuminance of object and road surface using unlit roadways. The variables were measured by vehicle type and by headlight lamp type. Based on the measurements, the distance where drivers can perceive an object ahead was calculated and then compared against such distance obtained by conventional visibility performance evaluation. According to the results, the evaluation method based on road surface illuminance is not appropriate when viewed from the visibility concept that is based on object-perceivable distance. Further, the results indicated a shorter object-perceiving distance even when road surface luminance is higher, thereby suggesting that road surface illumination and luminance are not the representative indices of nighttime visibility.
-
Supplemental Notes:
- This paper was sponsored by TRB committee AND40 Standing Committee on Visibility.
-
Corporate Authors:
500 Fifth Street, NW
Washington, DC United States 20001 -
Authors:
- Cho, Won Bum
- Jeong, Jun Hwa
- Yoon, Chunjoo
- Kim, Young Rok
- Park, Minho
-
Conference:
- Transportation Research Board 96th Annual Meeting
- Location: Washington DC, United States
- Date: 2017-1-8 to 2017-1-12
- Date: 2017
Language
- English
Media Info
- Media Type: Digital/other
- Features: Figures; References; Tables;
- Pagination: 15p
- Monograph Title: TRB 96th Annual Meeting Compendium of Papers
Subject/Index Terms
- TRT Terms: Contrast; Headlamps; Luminance; Night visibility; Surface course (Pavements)
- Subject Areas: Highways; Safety and Human Factors;
Filing Info
- Accession Number: 01626391
- Record Type: Publication
- Report/Paper Numbers: 17-05587
- Files: TRIS, TRB, ATRI
- Created Date: Feb 23 2017 2:56PM