Factors Influencing Light Scattering in the Eye

Abstract

Our vision in the twilight or dark is strongly affected by the intraocular light scattering (straylight). Of especial importance is to assess this phenomenon in view of the night driving. The authors have studied the spectral dependence of retinal straylight and estimated the possibility to reduce it with yellow filters and small apertures. For the measurements the direct compensation flicker method was used. The results show that this spectral dependence is close to Rayleigh's scattering (∝λ -4 ). As could be expected from the known data, the yellow filter should reduce retinal straylight, especially for blue light. However, in the experiments this scattering was not removed with such a filter but instead slightly increased. The optical apertures reduced light scattering in the eye, especially for red color.

Effect of Yellow Filters on the Vision

“…A yellow filter is not likely to improve the vision for car drivers under mesopic conditions. It should also be taken into consideration that a yellow filter increases the retinal straylight [13], especially if there is a strong luminous source in the visual field (the lights of cars coming from the opposite direction). This fact even more decreases the possibility that under mesopic conditions the yellow filters could improve the vision of car drivers.…”