ON THE VISIBILITY OF REAR SIGNALLING LAMPS THROUGH NATURAL FOG

This paper describes a study carried out to determine the factors affecting the visibility of braking lights through fog in daytime and night time conditions. Regression analysis of experimental results led to the following conclusions: (1) the visibility of braking lights through fog is proportional to the logarithm of its luminance defined in terms of attenuation through fog; (2) at night visibility is affected by the halo dimensions which increase with fog density; (3) visibility is independent of difference in visual angle due to observation distance; (4) the higher daytime luminance (10 times) gives the same visibility as at night; and (5) the foregoing findings can be applied to separated and to combined lamps. /TRRL/

• Corporate Authors:

  Ministry of Transport

  2-1-3 Kafumigaseki Chiyodaku
  Tokyo 100,   Japan 
• Authors:
  • Matsumoto, A
  • Ebihara, S
  • MASHIKO, J
  • Yaneyama, T
  • OKADA, T
• Publication Date: 1975-3

Language

• Japanese

Media Info

• Features: Figures; Photos; References; Tables;
• Pagination: p. 13-29
• Serial:
  • Volume: 50
  • Issue Number: 3

Subject/Index Terms

• TRT Terms: Brake lamps; Brightness; Daylight; Distance; Fog; Luminance; Night; Night visibility; Regression analysis; Visibility; Visibility distance
• Old TRIS Terms: Braking lights
• ITRD Terms: 1351: Brake light; 9008: Daylight; 2547: Fog; 525: Luminance; 9052: Night; 6783: Visibility; 6793: Visibility distance
• Subject Areas: Data and Information Technology; Highways; Safety and Human Factors; I82: Accidents and Transport Infrastructure;

Filing Info

• Accession Number: 00163175
• Record Type: Publication
• Source Agency: Transport and Road Research Laboratory (TRRL)
• Report/Paper Numbers: Proceeding
• Files: ITRD, TRIS
• Created Date: Feb 16 1978 12:00AM