L/M cone ratios as a function of retinal eccentricity

Abstract

Heterochromatic flicker photometry (HFP) was employed to estimate how the human long-wave sensitive (L) to middle-wave sensitive (M) cone ratio varies with retinal location in five color-normal males. Measurements were made at 0°, 25°, and 40° in the temporal retina. The HFP spectral sensitivities were fitted with a linear combination of L and M cone sensitivity functions derived from the Stockman and Sharpe1 cone fundamentals, according to genotype. For the white (6500 K, 3 log Td) adapting field conditions, the deduced L/M cone ratios of each subject were nearly constant at all measured eccentricities, with individual values ranging from 0.9:1 to 3.4:1. © 2000 John Wiley & Sons, Inc. Col Res Appl, 26, S128–S132, 2001