Glimne S, Seimyr G Öqvist, Ygge J, Nylén P, Brautaset R L
Unit of Optometry, Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden.
Work. 2013;45(4):431-7. doi: 10.3233/WOR-121575.
To introduce fixation disparity variance as an objective measure of visual discomfort. A higher variance in fixation disparity is indicative of more visual fatigue. This observation is based on the results from a study where we investigated how fixation disparity was affected by glare on a VDU. Participants. In total 16 subjects with normal vision participated in this study.
In a balanced repeated-measurement experiment, all subjects performed equal near-vision tasks. In addition to the condition of no glare three controlled conditions of glare were used: direct light, indirect light, and desk luminary. After each condition, the fixation disparity was measured 15 times using a computerized fixation disparity test.
The results showed that the average (mean) disparity was found to increase towards esophoric (crossed) with the adversity of the lighting conditions, but the differences were not significant. However, when analyzing the variation (standard deviation) within the 15 measurements and comparing these between conditions, we found that the direct light condition resulted in significantly higher variation compared to lighting condition of no glare and desk luminary lighting.
Based on these findings, we argue that fixation disparity variance may be a useful objective measure of visual fatigue.
引入注视差异方差作为视觉不适的客观指标。注视差异方差越高表明视觉疲劳越严重。这一观察结果基于一项研究结果，在该研究中我们调查了视屏终端（VDU）上的眩光如何影响注视差异。参与者。共有16名视力正常的受试者参与了本研究。
在一个平衡的重复测量实验中，所有受试者执行相同的近视力任务。除了无眩光条件外，还使用了三种受控眩光条件：直射光、间接光和台灯照明。在每种条件之后，使用计算机化的注视差异测试测量15次注视差异。
结果表明，随着照明条件变差，平均（均值）差异向集合性斜视（交叉性）增加，但差异不显著。然而，在分析15次测量中的变异（标准差）并比较不同条件之间的变异时，我们发现与无眩光和台灯照明条件相比，直射光条件导致的变异显著更高。
基于这些发现，我们认为注视差异方差可能是视觉疲劳的一种有用的客观指标。
