120名正常人对比敏感度分析

Analysis of Contrast sensitivty for 120 Normal subjects

中心视力是临床上评价视觉系统形觉功能最常用的指标。但是,由于中心视力实际上只反映视网膜黄斑中心凹区对细小目标的分辨能力,因而不能够全面地描述视觉系统的形觉功能特点。自从Schade 把空间光栅用于分析视觉系统的信息传递特征以后,Campbell 等首先测量了人视觉系统感受各种空间频率正弦光栅的阈值对比度,并将其倒数作为空间频率的函数,称为对比敏感度函数(Contrast sensitivity function,CSF)。由于CSF

Ranging from 0.5 to 22.8 cycles per degree(C/D),contrast sensiti-vity funetion(CSF)was determined for vertical stationary sinusoidalgratings at six spatial frequencies of 0.5,1,3,6,11.4and 22.8C/D in 12(?)normal sublects.It was showed that the CSF of normal subjectsappearanced as a bell-shape curve,the peak sensitivity was at 3C/Dand th sensitivity of higher and lower frequencies descend.Age.effec-ted CSF of normals,and the sensitivity was the highest for 21 to 30years younger.The sensitivity d clin d with the increasing of ag,andthe subjects up to 50 years had the lowest sensitivity.There was nosignificant diff rence between left and right eyes in normals,and thedifference of CSF between the two eyes did not be effected by ag butthat was different for different spatial frequencies.The effect of sexon CSF was not significant.The results were discussed.