designer's own words:
"Sand Glass" the LED traffic lights which inspired from the hour glass, one of the original timer that we've use for over century. Easy to see the light's color and estimate how long to wait or hurry to go obviously from the dropping pixels interface like a real sand glass.
The countdown number, 3-2-1, appears only while the yellow light's turn on to warn that the light's color will change in a few seconds. That's all make Sand Glass is a sensible communication design for everyone.presentation how it works perspective