Notice anything different about the signal on the left? Art Lebedev came up with this design which he details on his blog. It uses square indications instead of round ones, which Art contends are easier to see and more aesthetically pleasing. The round indications are a remnant of the first traffic signals that were created in the 1910's and 1920's. Those original electrical signals were circles because they used light bulbs. Now we use LEDs and could easily switch to a different shape.
A crazier idea – why do we need three indications stacked on top of each other (answer – it used to be for the color blind)??? Now that we have LEDs, we could put different indications in one spot. We could combine the traditional colors with traditional shapes to reinforce the message. This would reduce the size and cost of the signal indications, which in turn would allow us to use smaller metal poles which would save significant money. Then we run them with solar panels and wifi saving cable and wiring…..