Brake Lights

Ten sets of physical brake light assemblies from different car manufacturers, selected to represent a range of distinct light shapes from common models, were used in the experiments. Eight of the light assemblies contained LED sources, while
the remaining two employed incandescent bulbs. In order to make the LED/bulb comparison fairer, we included two samevehicle model assemblies with different bulb types. Specifically, these were two sets of Ford Focus hatchback and Fiat 500 units. For both models, we tested one pair of lights that contained incandescent bulbs and another set that used LED sources, but were otherwise identical in size and shape.

Table below lists the part numbers of the assembly units and bulbs while Figure shows one of the light pairs mounted for this
study (distractor rings when illuminated, and another showing the activated brake light).