Samenvatting
The author describes the results of experimental research into the influence of laterally positional luminance o 10, B= 1.8 sb in position 20 and 40 from the axis of vision which is exerted upon the contrast sensitivity od the eye. Furthermore, the author publishes the results of experiments concerning the problems of the additive effect of several lateral sources of light (o 70) upon the contrast sensitivity of the sight analuzer when being applied to the surrounding field (luminance 7 and 13nt); the luminance of the inner field was 130 nt. The respective experimental results are discussed. The increased contrast sensitivity is mainly ascribed to the positive induction from stimulated parts of the retinal periphery.