I believe WEEE (Waste Electrical and Electronic Equipment) recycling plants use computer vision directly. Recycling plans having multiple optical units with com

I believe WEEE (Waste Electrical and Electronic Equipment) recycling plants use computer vision directly. Recycling plans having multiple optical units with compressed air to then redirect the route of identified items, but I don't know whether this is image recognition or Raman / IR to identify the material. Certainly to differentiate plastics, it will be Raman / IR. An info vid on a recycling plant, showing the sort of scale and speed of sorting:- https://youtu.be/SIVKmwzWSuc?t=1m14s https://youtu.be/SIVKmwzWSuc?t=1m14s