When travelling along roads at night, drivers rely on well-lit paths and signage to direct them safely along dark routes. Road signs have lights to illuminate their lettering, while between lanes, long strings of small studs inform the positioning of each vehicle. Just as any cat caught in the headlights reveals two piercingly bright eyes, these road studs shine brighter the closer you drive towards them, reflecting the light from car headlights back to the vehicle.
Cat’s eyes were first produced by English inventor Percy Shaw in 1934. When Shaw was driving along a particularly dangerous section of road on a foggy night a year prior, he was unable to see where the road ended and the steep hills began. He usually used the reflection of his headlights off the tram tracks in the road to guide him, but on this misty night he realised the need for clearer road markings. None of the roadside objects reflected much light back to him, other than the eyes of a passing cat. This striking return of light led Shaw to design an unpowered device that