不同飞行光环境对飞行人员对比度视力的影响

目的研究不同模拟飞行光环境下，不同视力受试者对比度视力的差异，为保障飞行安全提供试验依据。方法通过测量双眼视力，24名受试者分为1.0/1.0组、0.8/0.8组、0.6/0.6组和0.4/0.4组（均为小数视力），每组6人，分别在模拟日光、迎光、背光、曙暮光和云上光环境下检测100%、80%、60%、40%、20%和10%对比度的视力。运用具有2个重复测量因素的三因素设计方差分析，比较不同光环境对不同视力者对比度视力的影响。结果光环境、视力和对比度3个因素间存在交互作用（P＜0.05）。进一步行两因素交互作用检验，光环境和对比度与视力间均存在交互作用（P均＜0.01），而光环境和对比度间不存在交互作用（P＞0.05）。在相同对比度下，与日光环境相比，各视力组在曙暮光和云上光的对比度视力下降（P＜0.05）；对于80%、60%、40%对比度，0.6/0.6和0.4/0.4组在迎光环境下的对比度视力低于日光（P＜0.05）；对于20%、10%对比度，各视力组在迎光环境下的对比度视力低于日光（P＜0.05）。在相同对比度下，与1.0/1.0组相比，0.6/0.6、0.4/0.4组在5种光环境下的对比度视力均下降（P＜0.05）；对于20%、10%对比度，0.8/0.8组在日光、迎光、曙暮光、云上光环境下的对比度视力低于1.0/1.0组（P＜0.05）；在相同的光环境和对比度下，0.4/0.4组的对比度视力低于其余视力组（P＜0.05）。结论光环境、对比度和视力水平对对比度视力的作用相互影响。近视飞行人员在不利光环境（如迎光、云上光和曙暮光）下观察低对比度目标时对比度视力严重下降，对飞行安全构成潜在的威胁，故应重视近视飞行人员的对比度视力检查。

Effects of different flight luminous environments on contrast visual acuity of pilots

Objective To study the differences in contrast visual acuity of subjects with different vision under different simulated flight luminous environments, so as to provide the experimental basis for ensuring flight safety. Methods Twenty-four subjects were recruited and divided into 1.0/1.0, 0.8/0.8, 0.6/0.6, and 0.4/0.4 (decimal vision) groups by measuring binocular vision, with six subjects in each group. Each subject was tested for 100%, 80%, 60%, 40%, 20%, and 10% contrast vision in simulated luminous environments of sunlight, facing light, backlight, twilight, and on-cloud light. Using a three-factor design ANOVA with two repeating measurement factors, the effects of different luminous environments on the contrast vision of people with different visual acuities were compared. Results There was an interaction between the three factors of the luminous environment, the vision, and the contrast (P<0.05). There was an interaction between the luminous environment and the vision (P<0.01), as was the contrast and the vision (P<0.01). There was no interaction between the luminous environment and the contrast (P>0.05). Compared with the sunlight environment and the same contrast, the contrast vision of twilight and on-cloud light decreased in each vision group (P<0.05). For 80%, 60%, and 40% contrast, the contrast vision of the 0.6/0.6 and 0.4/0.4 groups in the facing light environment was lower than that in the sunlight environment (P<0.05). For the contrast of 20% and 10%, the contrast vision of each vision group in the facing light environment was worse than that in the sunlight environment (P<0.05). Compared with the 1.0/1.0 group for the same contrast, the contrast acuity of the 0.6/0.6 and 0.4/0.4 groups decreased in the five simulated luminous environments (P<0.05). For 20% and 10% contrast, the contrast vision of the 0.8/0.8 group was lower than that of the 1.0/1.0 group in daylight, facing light, twilight, and on-cloud light (P<0.05). For the same light environment and contrast, the contrast acuity of the 0.4/0.4 group was worse than that of other vision groups (P<0.05). Conclusion The effects of the luminous environment, the contrast, and the vision on contrast visual acuity interact with each other. When myopic flight personnel observe low-contrast targets in unfavorable luminous environments such as facing light, on-cloud light, and twilight, their contrast vision is severely decreased, posing a potential threat to flight safety. Attention should be paid to the contrast vision examination of myopic flight personnel.