Measurements of chromatic sensitivity in the mesopic range

Abstract

We measured chromatic threshold sensitivity in the mesopic range using a combination of techniques that mask the detection of photopic and scotopic luminance contrast signals. The measurements were carried out at a number of light levels in the range 45–0.004 cd/m2, both foveally and with the stimulus centered 3.5° in the periphery. In order to investigate the effect of rod signals on chromatic detection thresholds in the near periphery of the visual field, we measured chromatic threshold ellipses when fully dark-adapted and during the cone plateau region of the dark-adaptation curve. The results confirm a number of previous observations and reveal new findings: © 2000 John Wiley & Sons, Inc. Col Res Appl, 26, S36–S42, 2001