ABSTRACT
The visual information revealed to a driver during night-time driving is obtained from
light provided by either:
* road lighting,
* vehicle headlights, or
* self-luminous sources.
As the eye functions better at high ambient light levels (Section 16.4.1), road lighting is
an essential part of road design. The general design principle for road lighting is that the
road environment and any objects in it need to be made sufficiently visible to:
(a) enhance traffic flow, by aiding the driver in the tracking and navigating task
(Section 16.5.1). This is done by displaying the pavement ahead, particularly the
pavement centreline and edges, as these provide navigational guidance by
permitting detection of:
* the current position of the vehicle,
* the future direction of the road, and
* any channelised intersections, lane markings, kerbs, and safety barriers.
