The story: Visible road markings
When driving at night-time, we almost entirely depend on being able to see the road markings. Such markings reflect headlights of the vehicle – not because markings are white or yellow, but rather because numerous glass beads embedded in the paint reflect the head light back into the eyes of the driver. The beads are optimized for returning most light exactly at the position of the driver’s eyes.
A person’s eyesight deteriorates over age. As a rule of thumb, we need twice as much light for every 13 years we grow older from around the age of 20. By the age of 85, a person’s sensitivity to light has decreased almost 32 times. Therefore, elderly people find it difficult to drive at night-time – and have even harder times during rain, when retroreflectivity is reduced significantly.
Over the past 50 years, the technologies of road markings and signs have developed considerably. Early on, DELTA grasped the challenge of road marking retroreflectivity and cooperated in the late 1970s with the road authorities of the Nordic countries. Taking a lead role in development and standardization of retroreflectivity of road markings and signs – then as now – DELTA remains at the forefront. Over time American and European standards emerged, and today these serve as the basis for test of retroreflectivity in most parts of the world. If the quality of road marking could not be checked, we most probably would see road markings of poor quality – as they are cheaper. As a result pavement marking visibility at night would be poor – especially during rain.
As car traffic increase, road markings and good signage have become crucial factors for the flow of traffic today. The challenge will not decrease in the coming years because modern safety systems in cars, such as’ lane departure warning’ systems – and in a few years driverless cars – depend on e.g. good quality visible road markings.
DELTA is also in the lead of development of test equipment for retroreflectivity of road markings and signs. DELTA’s RoadSensor measurement systems hold about 40 % of the world market and are employed in over 70 countries worldwide.
Read more here.