EFFECT OF WAVE-LENGTH CONTRASTS ON DISCRIMINATION THRESHOLDS UNDER MESOPIC VISION

VARIOUS STUDIES HAVE BEEN MADE OF THE EFFECT OF FILTERS, TINTED GLASSES AND WINDSHIELDS AS THEY AFFECT SEEING AT NIGHT. ON THE AVERAGE ALL RESULTS HAVE SHOWN A DELETERIOUS EFFECT ALTHOUGH INDIVIDUAL OBSERVERS SOMETIMES MAY SHOW A SLIGHT IMPROVEMENT. THESE VARIATIONS IN DIRECTION ARE UNDOUBTEDLY CHANCE ERRORS AS MIGHT BE EXPECTED FROM ANY LARGE NUMBER OF MEASUREMENTS. LAUER INVESTIGATED THE POSSIBILITY OF BENEFICIAL EFFECTS FROM CERTAIN WAVE-LENGTH BRIGHT HEADLIGHTS AT NIGHT BUT THAT LOSSES IN VISUAL INCREMENT OF NONLINEAR RELATIONSHIP BETWEEN INCREASED TRANSMISSION OF LIGHT AND LEGIBILITY OF LETTERS AS MEASURED BY THE CLASON ACUITY METER. MORE RECENTLY, STUDIES BY OTHERS HAVE SUPPORTED THESE EARLIER FINDINGS IN GREATER OR LESSER DEGREE. IN OTHER WORDS, THE HYPOTHESIS THAT SOME TYPES OF FILTERS WHICH LOWER LIGHT TRANSMISSIONS MAY INCREASE ACUITY AT NIGHT IS REJECTED. /AUTHOR/ LUMINANCE APPEAR TO BE SUFFICIENTLY GREAT.

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  • Supplemental Notes:
    • No 89, pp 62-67, 1 FIG, 7 TAB, 15 REF. Distribution, posting, or copying of this PDF is strictly prohibited without written permission of the Transportation Research Board of the National Academy of Sciences. Unless otherwise indicated, all materials in this PDF are copyrighted by the National Academy of Sciences. Copyright © National Academy of Sciences. All rights reserved.
  • Authors:
    • Stone, James A
    • Lauer, A R
  • Discussers:
    • Toenjes, D A
    • Lauer, A R
  • Publication Date: 1954

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  • Accession Number: 00220416
  • Record Type: Publication
  • Files: TRIS, TRB
  • Created Date: Apr 21 1994 12:00AM