VISUAL EFFECTS OF PINK GLASSES, GREEN WINDSHIELDS, AND GLARE UNDER NIGHT-DRIVING CONDITIONS

THE USE OF TINTED GLASS IN AUTOMOBILES IS DANGEROUS BECAUSE OF DECREASED VISUAL EFFICIENCY AT NIGHT. UNDER NIGHT-DRIVING CONDITIONS THE VISUAL ACUITY IS 20/32 ON SNELLEN TYPE THROUGH COLORLESS GLASS. LIGHT-YELLOW NIGHT- DRIVING GLASSES CHANGE THIS TO 20/34 THE SECOND SHADE OF PINK GLASS REDUCES VISUAL ACUITY TO 20/40, WHILE THE GREEN WINDSHIELD GLASS REDUCES IT, FURTHER TO 20/46. THE COMBINATION OF PINK GLASSES AND GREEN WINDSHIELD IS PARTICULARLY BAD, RESULTING IN A VISUAL ACUITY OF 20/60. EVEN MORE DAMNING IS THE EFFECT OF TINTED GLASS ON RESOLVING POWER DURING NIGHT DRIVING. THE THRESHOLD IS DECREASED FROM 10 TO 42 SECONDS ARC BY THE GREEB WINSHIELD ALONE. A PAIR OF OBJECTS WOULD APPEAR SEPARATE AT 100 FT. THROUGH A CLEAR WINDSHIELD, WHICH WOULD APPEAR SINGLE THROUGH A GREEN WINDSHIELD UNTIL THE DISTANCE HAD DECREASED TO 25 FT. OTHER FACTORS OF VISION, LIKE STEROSCOPIC ACUITY, INSTANT COUNTING SPAN, OR DISCRIMINATION OF ANGULAR VELOCITY, SIMULTANEOUS CONTRAST, INTENSITY CHANGE, OR DIRECTION OF A LINE TARGET, ARE LIKEWISE DEFECTIVE IN NIGHT-DRIVING CONDITIONS WITH TINTED GLASS. GREEN WINDSHIELD GLASS SHOULD BE IN A SEPARATE LAYER, TO BE MOVED ASIDE FOR NIGHT DRIVING. PERSONS WITH DEFECTIVE VISION, INCLUDING COLOR BLINDNESS OF THE COMMON TYPE, SHOULD BE ADVISED TO ADD AUXILIARY HEADLIGHTS TO THEIR AUTOMOBILES AND AVOID ANY TYPE OF TINTED GLASS FOR NIGHT DRIVING. SINCE GLARE IS INVERSELY PROPORTIONAL TO THE AREA OF THE SOURCE, AUTOMOBILE HEADLIGHTS SHOULD BE DESIGNED LARGER IN AREA. /SRIS/

• Supplemental Notes:
  • Vol 51, pp 15-23, 2 TAB, 31 REF
• Corporate Authors:

  American Medical Association

  535 North Dearborn Street
  Chicago, IL  United States  60610
• Authors:
  • Miles, P W
• Publication Date: 1954-1

Media Info

• Serial:
  • AMA Archives of Opthalmology
  • Publisher: American Medical Association

Subject/Index Terms

• TRT Terms: Automobiles; Color; Color blindness; Driving; Glare; Night; Vision; Visual perception; Windshields
• Uncontrolled Terms: Driving conditions
• Old TRIS Terms: Glasses; Tints /materials/
• Subject Areas: Highways; Safety and Human Factors;

Filing Info

• Accession Number: 00220806
• Record Type: Publication
• Source Agency: Nat Safety Council Safety Res Info Serv
• Files: TRIS
• Created Date: Jul 6 1970 12:00AM