LATEST RESEARCH IN TUNNEL LIGHTING IN JAPAN

TWO EFFECTS ARE DISCUSSED. FIRST, AS THE DRIVER APPROACHES A TUNNEL ENTRANCE FROM A SUNLIT DRIVEWAY, THE ENTRANCE APPEARS TO BE A BLACK HOLE. SECOND, AS HE ENTERS THE TUNNEL, THE CHANGE IN LEVEL OF ILLUMINATION CAUSES A BLACK-OUT, SO THAT THE INSIDE OF THE TUNNEL APPEARS BLACK. IN NEITHER CASE DOES THE DRIVER HAVE ENOUGH VISUAL INFORMATION TO FEEL SECURE. PREVIOUS WORK ON THESE TWO PHENOMENA IS REVIEWED, AND EXPERIMENTS CONDUCTED ON THE FORMER ARE REPORTED. IT WAS FOUND THAT THE LUMINANCE LEVEL REQUIRED AT THE ENTRANCE OF A LONG TUNNEL IS A FUNCTION OF THE TIME ELAPSED SINCE THE DRIVER BEGAN TO FIX VISUAL ATTENTION ON THE TUNNEL ENTRANCE. THE DRIVER'S EYES DO NOT REMAIN ADAPTED TO THE AVERAGE OUTDOOR LUMINANCE UP TO THE TIME HE ENTERS THE TUNNEL. THE ADAPTATION LUMINANCE OF THE DRIVER APPROACHING A TUNNEL ENTRANCE DECREASES FROM ABOUT 0.167 TO 0.1 OF THAT COMMONLY SUPPOSED. A CHANGE IN THE APPARENT SIZE OF THE TUNNEL ENTRANCE HAS LITTLE EFFECT ON THE PERCEPTION OF OBJECTS UNDER A GIVEN OUTDOOR LUMINANCE AT A DISTANCE WITHIN 200 METERS FROM THE TUNNEL ENTRANCE. THESE FINDINGS ARE EMPLOYED TO DERIVE A NEW DESIGGN PROCEDURE FOR THE LIGHTING OF A LONG-TUNNEL ENTRANCE.

  • Authors:
    • NARISADA, K
  • Publication Date: 1972-8

Media Info

  • Features: Figures; Photos; References; Tables;
  • Pagination: p. 9-27
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00221787
  • Record Type: Publication
  • Files: TRIS
  • Created Date: Feb 3 1973 12:00AM