Keeney A H, Renaldo D P
Can J Ophthalmol. 1975 Jul;10(3):367-76.
Protection of the eyes by safety type spectacle, sunglass and goggle lenses has received considerable attention in recent years. Such protection can be enhanced by design of the frame. We report from 476 lenses mounted in 238 frames and subjected to 9,397 impacts. Maximum blows were delivered by a one inch diameter steel ball falling from a height of 122 inches. Results indicated that the force required to fracture lenses in plastic frame mountings was more than twice that required for fracture of identical strength lenses in wire rims. Minus cylindrical lenses were the most frangible. The lowest fracture and posterior dislocation rates were found in industrial plastic frames with a retaining lip. Greater energy attenuation can be induced in a heat tempered glass lens by even edge compression. Good lens and frame design, when properly correlated, should provide impact attenuation distinctly exceeding conventional standards.
近年来，安全型眼镜、太阳镜和护目镜镜片对眼睛的保护受到了广泛关注。通过镜框设计可增强这种保护。我们报告了安装在238个镜框中的476片镜片，并对其进行了9397次冲击试验。最大冲击力由一个直径一英寸的钢球从122英寸的高度落下产生。结果表明，塑料镜框安装的镜片破碎所需的力是相同强度的金属丝边框镜片破碎所需力的两倍多。负柱面镜片最易碎。在带有固定唇的工业塑料镜框中，镜片破碎率和后脱位率最低。通过均匀的边缘压缩，热钢化玻璃镜片可产生更大的能量衰减。良好的镜片和镜框设计，若能恰当配合，应能提供明显超过传统标准的冲击衰减效果。
