Abstract

The visual threshold of the fovea is raised by a surrounding ‘glare’ ring of bright light. If this is due entirely to scattered light, then the equivalent uniform background that raises the threshold equally will bleach the cone pigments equally. The equivalence of bleaching was measured by two different techniques: retinal densitometry, and the effect on subsequent dark adaptation. Both agree that the background which matches the glare in raising the threshold for foveal cones also matches it (correct to 0.1 log unit) in bleaching the pigment in those same cones.

© 1966 Optical Society of America

Increment Threshold and Dark Adaptation*

W. A. H. Rushton
J. Opt. Soc. Am. 53(1) 104-109 (1963)

Analysis of Photopic and Scotopic Function in an Incomplete Achromat*

Irwin M. Siegel, Clarence H. Graham, Harris Ripps, and Yun Hsia
J. Opt. Soc. Am. 56(5) 699-704 (1966)

Single-Variable Anomaloscope Matches During Recovery from Artificial Red Blindness*†

Howard D. Baker
J. Opt. Soc. Am. 56(5) 686-689 (1966)

Validation of an Indicator of Mammalian Retinal Receptor Response: Density of Stain as a Function of Stimulus Magnitude*

Jay M. Enoch
J. Opt. Soc. Am. 56(1) 116-123 (1966)

Positive Afterimage as a Background Luminance*

Norma D. Miller
J. Opt. Soc. Am. 56(11) 1616-1620 (1966)