The circles are just an illustration and not part of the idea.
The contamination of the night sky with light is not only influenced by the color of the emitted light but also by its overall amount.
Lanterns that are dimmed by default and only shine brighter when someone walks across. For this propose, we use specific tiles consisting of an electromagnetic generator and built to cover the path. A single footstep makes the generator vertically displace due to the weight of the human body. The resulting clean energy of about eight Watt can be used to let the lanterns shine brighter for further thirty seconds when someone walks past.1
- Switch-Plan Limited etc. (2021): Kinetic floor tiles: how do they work?