Light adaptation in letter contrast sensitivity: The influence of optical and neural mechanisms. (August 2014)

• Record Type: Journal Article
• Authors: Arranz, I; Matesanz, BM; Issolio, L; Menéndez, JA; Mar, S; Aparicio, JA
• Is Part Of: Lighting research & technology. Volume 46:Number 4(2014:Aug.)
• Page Start: 476
• Page End: 488
• Publication Date: 2014-08
• Subjects: Lighting -- Periodicals; 621.32
• DOI: 10.1177/1477153513484633
• Languages: English
• ISSNs: 1477-1535

Abstract

This work discusses the relative significance of optical and neural mechanisms in letter contrast sensitivity under different conditions of environmental lighting. A study was carried out on 26 eyes with normal ocular health. Sixteen lighting conditions were obtained by combining different test luminances (from 10 cd/m 2 to 600 cd/m 2 ) and surround luminances (from 1 cd/m 2 to 600 cd/m 2 ). The results reveal a significant influence of optical factors (pupil size variations and glare effects) on contrast sensitivity when surround luminance changes, and a dominance of neural effects when test luminance changes. Furthermore, test size and illumination conditions are identified for which letter threshold contrasts are not sensitive to surround luminance changes.