Two drivers drove an automobile over a 15 mile two-lane course in the daytime and at night using American and European low beam headlamps and a mid beam. The eye fixations of the drivers were measured, using a silicon diode TV camera and light reflection from the cornea as the recording device. Comparisons between the eye fixations used in daytime and at night, suggested that dwell time was longer when looking straight ahead at night than in the daytime, and there was a reduction in the proportion of the viewing time devoted to the left lane at night than in the day, when there was no oncoming vehicle. Drivers looked at approaching vehicles in both day and night conditions with glance durations of intermediate length, which increased in frequency as the separation distance between the vehicles decreased. At night preview distances were less than in the day. The characteristic shift of the eye fixations in the direction taken by the road was found in this study, in both day and night driving. At night the eye fixations were influenced by the characteristics of the beam pattern being used. On left curves the American and European low beams provided eye fixations which most closely resembled those used in daytime, whereas on straight sections and particularly on right curves the mid beam provided the most compatible distribution of glances. A revised composite mid beam, incorporating some characteristics of the European low beam was suggested as an improved meeting beam.
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