目的　实验探讨模拟直升机轻度急性缺氧暴露对飞行人员对比敏感度和对比视力的影响程度 ,为直升机飞行员供氧必要性提供依据。　方法　在分别呼吸空气和低氧混合气条件下 ,用多功能眩光检测仪在 95 cd/ m2亮度下 ,检查 30名飞行人员的对比敏感度函数 (CSF) ;用投射式双变量对比视力表在 90 L x照度下 ,检查 31名飞行人员的对比视力 (CVA) ;同步监测心率、血氧饱和度。　结果　飞行人员低氧 CSF综合 7个空间频率平均下降率为 30 .4% ,低氧低、中、高频 CSF平均下降率分别为 2 1.0 %、13.4%和 48.1% ;低氧 CVA综合前 12个对比度平均下降率为 11.8% ,低氧高、中、低对比度视力平均下降率分别为 11.8%、9.7%和 15 .4% ;对比敏感度及对比视力下降率与缺氧后心率变化率、血氧饱和度平均值显著相关 (P<0 .0 5 )。　结论　直升机飞行高度 (轻度急性缺氧 )对视觉系统功能有显著的影响 ,对目标背景需要精确识别时应该供氧或采取一定的缺氧防护措施 Objective To explore the effect of simulated mild acute hypoxia exposure on contrast sensitivity and contrast vision of pilots, and provide evidence for the necessity of helicopter pilots’ oxygenation. Methods The contrast sensitivity function (CSF) of 30 pilots was examined with a multi-function glare detector at a brightness of 95 cd / m2 under a mixture of breathing air and hypoxia respectively. Under the illumination of 90 L x, 31 pilots’ contrast acuity (CVA) was examined; heart rate and oxygen saturation were monitored simultaneously. Results The average rate of decline in 7 spatial frequencies of flight hypoxemia was 30.4%, while the average rate of hypoxemia, middle and high frequency CSF was 2 1.0%, 13.4% and 48.1% respectively. The average rate of decrease in contrast was 11.8%, and the average rate of decrease in high, middle and low contrast was 11.8%, 9.7% and 15.4% respectively. Contrast sensitivity, The mean values ​​of oxygen saturation were significantly correlated (P <0.05). Conclusions The helicopter flight altitude (mild acute hypoxia) has a significant effect on the visual system function. Oxygen supply or oxygen protection measures should be taken when the target background needs to be precisely identified