Neary C
MRC Applied Psychology Unit, Cambridge, UK.
Ophthalmic Physiol Opt. 1989 Oct;9(4):440-6.
Monocular accommodation was measured by a laser optometer while two subjects viewed a letter matrix target illuminated by steady or intermittent (300, 100, 50 and 25 Hz) light and presented at a number of optical distances (0.5, 1.5, 2.5, 3.5 and 4.5 D). At certain rates of intermittent illumination, both above (50 Hz) and below (25 Hz) flicker fusion, an increased accommodation response was found. This increase occurred at all optical distances, except for the distance closest to each subject's dark focus, and resulted in a more accurate accommodation response for one subject, and a less accurate one for the other. Furthermore, for both subjects, evidence of an increase in the amplitude of the fluctuations in accommodation at 50 and 25 Hz was found for the higher stimulus levels. The implications of these findings for the control of accommodation and for practical problems of visual performance in the environment, such as visual discomfort associated with fluorescent lighting and intermittently illuminated visual display units, are discussed.
在两名受试者观看由稳定或间歇（300、100、50和25赫兹）光照明并呈现于多个光学距离（0.5、1.5、2.5、3.5和4.5屈光度）的字母矩阵目标时，使用激光验光仪测量单眼调节。在高于（50赫兹）和低于（25赫兹）闪烁融合的特定间歇照明速率下，发现调节反应增强。这种增强在所有光学距离处均会出现，但最接近每个受试者暗焦点的距离除外，并且对于一名受试者而言，这导致调节反应更准确，而对另一名受试者则导致调节反应不太准确。此外，对于两名受试者，在较高刺激水平下，发现50和25赫兹时调节波动幅度增加的证据。讨论了这些发现对调节控制以及环境中视觉性能实际问题（如与荧光灯和间歇照明视觉显示单元相关的视觉不适）的影响。
