MODERN LIGHT SOURCES FOR HIGHWAYS

VISION IS NOT THE SAME IN THE LIGHT OF MERCURY AND SODIUM LAMPS WHEN ALL CONDITIONS THAT CAN BE EXPRESSED IN PHOTOMETRIC UNITS ARE IDENTICAL, I.E., WHEN ONLY THE COLOR OF THE LIGHT VARIES. A RATIO OF 3:2 WAS PREVIOUSLY FOUND BETWEEN THE AVERAGE LUMINANCE IN THE VISUAL FIELD OF MERCURY LAMPS AND THAT OF LOW-PRESSURE SODIUM LAMPS, ASSUMING LIGHT FOR EQUAL VISUAL PERFORMANCE. THIS RATIO HAS BEEN CONFIRMED IN CURRENT RESEARCH AT LOW VALUES OF BOTH THE AVERAGE LUMINANCE OF THE VISUAL FIELD AND OF THE CONTRAST OF THE VISUAL TASK. THE RATIO OF HIGH-PRESSURE TO LOW-PRESSURE SODIUM LAMPS IS AROUND 5:4. WITH RESPECT TO GLARE REDUCTION, THE PREVIOUSLY FOUND RATIO OF 3:2 FOR THE ADMISSIBLE LUMINANCE OF LUMINAIRES AT EQUAL DEGREES OF GLARE BETWEEN LOW-PRESSURE-SODIUM AND MERCURY LIGHT WAS ALSO CONFIRMED. UNDER EQUAL PHOTOMETRIC CONDITIONS, THE ECONOMY OF LIGHTING INSTALLATIONS INCREASES IN THE ORDER MERCURY, HIGH-PRESSURE SODIUM, AND LOW-PRESSURE SODIUM.

• Authors:
  • de Boer, J B
• Publication Date: 1973-6

Media Info

• Pagination: p. 22
• Serial:
  • Lighting Design and Application
  • Volume: 3
  • Issue Number: 6
  • Publisher: Illuminating Engineering Society

Subject/Index Terms

• TRT Terms: Brightness; Drivers; Glare; Luminaires; Mercury vapor lamps; Sodium vapor lamps; Street lighting; Vision
• Old TRIS Terms: Driver vision; Mercury lamps; Sodium lamps
• Subject Areas: Highways; Safety and Human Factors;

Filing Info

• Accession Number: 00222232
• Record Type: Publication
• Files: TRIS
• Created Date: Jul 17 1973 12:00AM