Can scattered light improve visual performance?
Can scattered light improve visual performance?
复制标题
散射光可以改善视觉表现吗？
DOI：
10.1111/j.1755-3768.2012.4281.x
复制
发表时间：
2012
影响因子：
3.4
通讯作者：
PATTERSON E
中科院分区：
文献类型：
--
作者：
PATTERSON E
目的在明亮光源存在的情况下，眼睛内介质散射的光会降低物体对比度，还会导致视觉不适。然而，在视网膜上添加均匀的面纱光可以通过增加视网膜照度来改变视网膜的敏感度。由于眩光光源的存在，目标对比度的降低和视网膜敏感度的改变对对比敏锐度(CA)阈值的影响程度仍有待确定。我们研究了眩光光源强度、周围亮度和测试目标在视网膜上的位置对CA的影响。目的确定可以提高视觉表现的眩光光源强度范围和背景适应水平。方法对45名视力正常的受试者进行调查。采用心理物理闪光消除试验(《眼科与生理光学》，17,171,1997)测量散射光在眼内的数量和角度分布。使用对比视力评估测验(ASEM，74,551-559,2003)测量CA阈值。研究了3种眩光光源强度(0、1.35和19.21 lm/m^2)、3种偏心(5、10和15度)和3种背景亮度(1、2.6和26 cd/m^2)。结果测量了上述测试目标/眩光光源参数的CA阈值。此外，还评估了每个受试者的眼睛散射功能，并用测量的参数来预测遮盖眩光对CA阈值的影响。结论低强度眩光可以改善高中视范围的CA。高强度眩光会增加阈值，但这种对比度敏感度的损失通常比基于眼睛前向光散射引起的面纱眩光亮度的预测要小。
PurposeLight scattered by the media within the eye reduces object contrast and can also cause visual discomfort, in the presence of bright light sources. The addition of uniform veiling light over the retina can, however, change retinal sensitivity by increasing retinal illuminance. The extent to which reduction of target contrast and changes in retinal sensitivity caused by the presence of a glare source affect contrast acuity (CA) thresholds remains to be established. We investigate how CA is affected by glare source intensity, surround luminance and test target location on the retina. The aim is to determine the range of glare source intensity and background adaptation level that can improve visual performance.Methods45 subjects with normal vision were investigated. A psychophysical flicker‐cancellation test (Ophthalmic & Physiological Optics, 17, 171, 1997) was used to measure the amount and angular distribution of scattered light in the eye. CA thresholds were measured using the Contrast Acuity Assessment test (ASEM, 74, 551‐559, 2003). Three glare source intensities (i.e., 0, 1.35 and 19.21 lm/m^2 in the pupil plane), three eccentricities (5, 10 and 15 degrees), and three background luminances (1, 2.6 and 26 cd/m^2) were investigated.ResultsCA thresholds were measured for the test target / glare source parameters listed above. In addition, the scatter function of the eye was assessed for each subject and the measured parameters were used to predict the effect of veiling glare on CA thresholds.ConclusionLow intensity glare can improve CA in the high mesopic range. High intensity glare yields increased thresholds, but this loss of contrast sensitivity is, in general, smaller than predictions based on veiling glare luminance caused by forward light scatter in the eye.