REFLEX REFLECTOR PERFORMANCE CRITERIA
REFLEX REFLECTORS ARE SPECIAL TYPES OF MIRRORS WHICH HAVE THE CHARACTERISTIC OF RETURNING A SUBSTANTIAL FRACTION OF THE INCIDENT LIGHT TOWARD THE SOURCE FROM WHICH IT ORIGINATES REGARDLESS OF THE INCIDENT ANGLE. BECAUSE OF THEIR PECULIAR OPTICAL CHARACTERISTICS, REFLEX REFLECTORS APPEAR VERY MUCH BRIGHTER THAN EVEN THE BEST OF WHITE PAINTS WHEN ILLUMINATED UNDER SIMILAR CONDITIONS AND ARE THUS VERY USEFUL IN MARKING ROADWAY OBSTACLES. A REVIEW OF THE VISUAL METHODS OF APPRAISAL HAS BEEN PREPARED TOGETHER WITH TYPICAL DATA SHOWING THE VARIATIONS FOUND WHEN THE HUMAN EYE IS USED AS A MEASURING INSTRUMENT. A PHOTO-ELECTRIC PHOTOMETER IS DESCRIBED WHICH PERMITS THE PHYSICAL MEASUREMENT OF THE LIGHT FLUX FROM REFLEX REFLECTORS WHEN THEY ARE USED UNDER CONDITIONS WHICH APPROXIMATE FIELD USAGE. DATA ARE SHOWN FOR THE CHANGES IN SPECIFIC INTENSITY WHEN THE DIFFERENT TYPES OF REFLECTORS ARE USED UNDER VARYING CONDITIONS OF DIVERGENCE ANGLE, ENTRANCE ANGLE, ORIENTATION ANGLE, TEST DISTANCE, SIZE OF LIGHT SOURCE, SIZE OF REFLECTOR, SIZE OF RECEIVER AND COLOR OF LIGHT SOURCE. A RECOMMENDED TEST PROCEDURE BASED UPON STANDARDIZED CONDITIONS IS OUTLINED. /AUTHOR/
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Supplemental Notes:
- 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
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Authors:
- FINCH, D M
- Publication Date: 1951
Media Info
- Media Type: Print
- Features: Appendices; Figures; References;
- Pagination: pp 21-40
- Monograph Title: Reflectors and night visibility
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Serial:
- Highway Research Board Bulletin
- Issue Number: 34
- Publisher: Highway Research Board
Subject/Index Terms
- TRT Terms: Eye; Mirrors; Optical properties; Photocells; Photometers; Reflectorized materials; Test procedures
- Subject Areas: Highways; Operations and Traffic Management; Safety and Human Factors;
Filing Info
- Accession Number: 00220333
- Record Type: Publication
- Files: TRIS, TRB, ATRI
- Created Date: Apr 21 1994 12:00AM