Elsner A E, Burns S A, Webb R H
Schepens Eye Research Institute, Boston, Massachusetts 02114.
J Opt Soc Am A. 1993 Jan;10(1):52-8. doi: 10.1364/josaa.10.000052.
The distribution of cone photopigment across the retina affects the amount of light captured by cones at each retinal location. Cone photopigment optical density is measured in two ways, with reflectometry and/or with color matching. Color matching measures a higher optical density than does reflectometry. Control experiments confirm that large-field color matches measure photopigment optical density toward their outer edge. There is qualitative agreement as to photopigment distribution from both techniques near the fovea. Beyond 1 deg, color matching indicates little decrease in photopigment with increasing eccentricity, whereas retinal densitometry shows a steep decline in photopigment. The decrease in perifoveal optical density measured with reflectometry is attributed to the decrease in cone coverage from fovea to perifovea as rods and interphotoreceptor spaces increase. Differences among subjects in photopigment distribution near the fovea, measured with both techniques, reflect differences in the specialization of the foveal center for cone length and/or photopigment concentration per cone, which are factors influencing results from both techniques.
视锥色素在视网膜上的分布会影响每个视网膜位置的视锥细胞捕获的光量。视锥色素的光密度通过两种方法测量，即反射测量法和/或颜色匹配法。颜色匹配法测得的光密度高于反射测量法。对照实验证实，大视野颜色匹配测量的是其外缘处的色素光密度。两种技术在中央凹附近对视锥色素分布的定性结果一致。在超过1度的区域，颜色匹配表明视锥色素随着离心率增加几乎没有减少，而视网膜密度测量显示视锥色素急剧下降。反射测量法测得的中央凹周围光密度的降低归因于从中央凹到中央凹周围视锥细胞覆盖率的降低，因为视杆细胞和光感受器间腔增加。两种技术测量的中央凹附近视锥色素分布在个体之间的差异，反映了中央凹中心在视锥细胞长度和/或每个视锥细胞色素浓度方面的特化差异，这些都是影响两种技术结果的因素。
