I have been working on nitrogen dioxide visualisation for some time now. In order not to duplicate anything here, I would refer you to the following two articles:
https://jakob-volkmer.de/stadt_luft_anzeiger-home/
https://jakob-volkmer.de/stadtluftanzeiger-studien/
I have completely dispensed with LEDs in a second large version of the urban air indicator. This saves a lot of power, compared to the versions with bright LEDs. But above all, it also brings an aesthetic change. This display for home use is designed to be placed in a living or working environment and to permanently show the air quality. However, you don't always want to have a glowing or flashing object in the room, but rather a device that is not distracting and can be easily integrated into an interior design.
The design of the Stadtluftanzeiger 2.0 was created with these considerations in mind. The housing is made of oak plywood and gives the entire device a high-quality, no-frills appearance. An e-paper display was chosen for the actual output medium, which at first glance looks like normal paper, does not glow and is still perfectly legible even in direct sunlight. Also very cool: When the display is not being updated, it does not need any power and therefore still shows old air data even when unplugged.
The device displays the current nitrogen dioxide and particulate matter (PM10) values at a previously selected measuring station via two curved bar displays inspired by an analogue barometer. With a click of the button on the back, you can switch between self-configured stations.
I had a small series of this indicator produced and organised a workshop to build it.
