Visible Light Communication
Stefan Schmid (Disney Research Zurich)
Manuela Hitz (Disney Research Zurich)
Giorgio Corbellini (Disney Research Zurich)
Thomas Richner (ETH Zurich)
Josef Ziegler (ETH Zurich)
Theodoros Bourchas (ETH Zurich)
Thomas R. Gross (ETH Zurich)
Stefan Mangold (Disney Research Zurich)
Light Emitting Diodes (LEDs) are used in consumer electronics, toys, light bulbs, cars, and monitors. With LEDs, it is possible to control light brightness at a frequency much higher than conventional light bulbs: LEDs can be switched on and off at very high rates. As result, LED-based lighting can be used for wireless communication services by modulating the intensity of the emitted light. Further, LEDs can also be used as receivers just like photodiodes. We call this concept Visible Light Communication (VLC) with LED-to-LED networking. Significant research contributions have been achieved by Disney Research in the area of networked systems for VLC. VLC creates opportunities for low-cost, safe, and environmentally friendly wireless communication solutions. We focus on connected toys and light bulb networks. Our work targets a full system design that spans from hardware prototypes to communication protocols, and applications.
LED-to-LED Software Protocol
LED-to-LED Visible Light Communication allows interaction between toys by only using LEDs: an LED is used to transmit and to receive data messages. No dedicated hardware is required. When multiple devices are networked with each other, we organize the communication with our software protocols.
Magic Princess Dress
A magic wand with an LED magically triggers light effects on a princess dress. Many LEDs are embedded into the dress. When the magic wand is pointed towards the dress, it comes to life at exactly this location, because all LEDs can receive from the wand.
Toy and Smartphone
Communication between smartphones and toys can be achieved using VLC by using the toy LEDs and the phone’s camera, display, and flashlight. The phone sends messages with the flashlight and receives messages from the LEDs with the camera.
Low-cost toy cars use LEDs to create illumination and lighting effects. Using these LEDs, cars can communicate with each other, based on our LED-to-LED microcontroller software. The brightness of an LED is modulated faster than human eye sensitivity to transmit and receive light messages without flickering.