Figure 6. Phase advances of M-cone flickering lights.

Phase advances of sinusoidally alternating, M-cone-isolating pairs of 500 and 656 nm (dotted circles), 540 and 656 nm (dotted triangles), and 577 and 656 nm (dotted inverted triangles) lights, each of which were equal for the L-cones, required to null 656 nm flicker, and mean fits of the time delay model (continuous lines). Subjects: AS (top panel) and DP (bottom panel). The radiances of the combined targets were chosen so that the opposite-phase flicker was L-cone-equated. For AS: 9.70 and 10.21 (500 and 656 nm), 9.48 and 10.38 (540 and 656 nm), 9.66 and 10.61 (577 and 656 nm), and 11.36 (656 nm) log₁₀ quanta s⁻¹ deg⁻². For DP: 9.70 and 10.16 (500 and 656 nm), 9.76 and 10.66 (540 nm), 9.66 and 10.60 (577 and 656 nm), and 11.36 (656 nm) log₁₀ quanta s⁻¹ deg⁻². Backgrounds: 12.55 (658 nm) and 10.90 log₁₀ quanta s⁻¹ deg⁻² (410 nm, present for the 500 nm target only).