Various traffic lights installed on cars to ensure safe driving. There are two types of lights and signal lights. From 1905 to 1912, in order to solve the problem of lighting the road ahead, a spotlight-type acetylene headlamp was installed, and a kerosene lamp was installed as the rear license plate lamp. From 1945 to 1947, the minimum required external lamps and lanterns were finalized. Qualified car lights should meet the corresponding luminosity, chromaticity and basic environmental test specifications.