The Effect of Diffusion Blur on Central and Peripheral Vision in Normal Adults

Han, Sueng Han; Chung, Gang Wook; Lee, Jong Bok; Lee, Young Ghee

Abstract

Diffusion blur, caused by liquid crystal windows, reduces contrast sensitivity and luminance, so visual acuity is decreased. Moreover, the windows' optical characteristics are similar to those of the cataractous lens. We measured the effect of liquid crystal window on central and peripheral visual acuity using Snellen and grating visual acuity charts. The subjects were 10 normal adults, therefore 20 eyes. We measured the voltage of the liquid crystal window at which the subjects could read the visual acuity chart through the liquid crystal window. In central vision, visual acuity was overestimated according to the Snellen chart, when compared to the results measured by those grating chart. But in peripheral vision, there were no differences between the two visual acuity charts. These results suggested that grating acuity has some limitations when used as a visual acuity test for cataractous patient. The ability of liquid crystal windows to cause diffusion blur suggests they could be used for foUowup observation in treatment of amblyopia or macular diseases.