Open AccessEffects of Luminance and Contrast on Visual Acuity, Ages 16 to 90 Years
Author(s) -
O. W. Richards
Publication year - 1977
Publication title -
optometry and vision science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.779
H-Index - 97
eISSN - 1538-9235
pISSN - 1040-5488
DOI - 10.1097/00006324-197703000-00010
Subject(s) - luminance , contrast (vision) , visual acuity , optometry , audiology , chart , ophthalmology , psychology , medicine , optics , mathematics , physics , statistics
Visual acuity of persons aged 16 to 90 years was measured with Snellen letters of varied contrast at 10, 1, 0.1, and 0.01 fl chart luminances. Percentage losses of seeing with age were computed. At 10 fl luminance, perception of high- and medium-contrast letters has changed little at age 40, but about twice as much light is needed to see low-contrast letters as at age 20. By age 70, no 2-min-subtense (20/40) letters were seen at 0.01 fl luminance. The need of older people for increased lighting during indoor tasks and night driving is discussed.