Reflective Lane Markers : Jacob Rabinow

Reflective Lane Markers
ca. 1977

Driving often inspired Rabinow’s inventive thinking. His reflective lane markers are a case in point. While driving in a rainstorm near his home in Bethesda, Maryland, he began to have trouble seeing the white lines on the road. He thought it would be nice to embed reflectors in the road surface as was common in the South and some parts of the West. However, he knew why that wasn’t done in many parts of the country, including the Mid-Atlantic region where he lived. To reflect horizontally directed light, the markers had to stand above the surface of the road. Such reflectors would be torn out by snowplows in the winter. Rabinow put his mind to inventing a flush marker. By gluing bicycle reflectors, which are really a series of corner-cube reflectors, to a right-angle prism with its hypotenuse horizontal (as if it were flush to the road surface), he was able to bend light into the device and reflect it back out in the same direction from which it came. Rabinow’s patent was not marketable given the huge investment – Rabinow estimated one million dollars – necessary to test the markers in realistic conditions.