Visual Considerations of Man, the Vehicle, and the Highway

This treatise represents a short physiological optics review for designers and users of automobiles. It starts with a description of the macroscopic and microscopic anatomy of the visual organ. The movements of the eyes, the visual field, and fixation field are described in a more detailed way, together with the sensory mechanisms which comprise adaptation, contrast sensitivity, visual acuity, perception of motion, and perception of direction and distances. In view of their importance in driving, special attention was given to the problems of glare, the time factor in vision, and the visual problems in motion. A comparison of visibility of red versus green concludes the paper. An effort has been made to confine the text to the phenomena which are basic and necessary for general understanding and have an obvious bearing on automotive design and driving procedures.