Abstract

Using a testfield subtending a visual angle of 5 degrees, dark adaptation functions were obtained with six test-exposures (1.0, 0.5, 0.1, 0.04, 0.02, and 0.01 sec) both from the central retina, and from the temporal parafovea. The functions for both retinal locations were found to vary systematically in relation to duration of testflash. With increasing test-exposure time, the final cone levels as well as the final rod levels are at lower threshold brightnesses. The sensitivity for a given test-exposure time is greater in the central retina than in the parafovea for the photopic range of vision, whereas the sensitivity for the scotopic range is greater in the parafovea than in the central retina.

© 1951 Optical Society of America

Dark Adaptation Level and Size of Testfield

Ernst Wolf and Michael J. Zigler
J. Opt. Soc. Am. 40(4) 211-218 (1950)

The Influence of Surround Brightness and Short Wave Components of Radiation on Dark Adaptation

Michael J. Zigler, Ernst Wolf, and Esther Shores King
J. Opt. Soc. Am. 41(5) 354-359 (1951)

Location of the Break in the Dark Adaptation Curve in Relation to Pre-Exposure Brightness and Pre-Exposure Time

Ernst Wolf and Michael J. Zigler
J. Opt. Soc. Am. 44(11) 875-879 (1954)

Dark Adaptation to Intermediate Levels and to Complete Darkness*

Robert G. Hattwick
J. Opt. Soc. Am. 44(3) 223-228 (1954)

Vision and Resolution in the Central Retina*†

Brian O’Brien
J. Opt. Soc. Am. 41(12) 882-894 (1951)