Extracting information from surface coatings

A system for extracting information from a surface coated with a coating containing quantum dots, the system comprising:

• a first light source for illuminating the surface with a first light, and a second light source for charging, using a second light, the quantum dots in the surface coating to emit light;
• a scanner for scanning the surface coating, using the first light, to obtain a scan of the surface coating giving colors of the surface coating, and for scanning the surface to obtain a quantum dot scan giving colors of the quantum dots;
• and
• a processing unit for filtering the colors of the quantum dots, using the colors of the surface coating, to obtain filtered quantum dot colors, and for processing the filtered quantum dot colors to identify data encoded in the quantum dots, including obtaining metadata of the surface coating from hues of the filtered quantum dot colors.

A method of determining information from a surface coated with a coating containing quantum dots, the method comprising:

• illuminating the surface coating with a first light;
• scanning the surface coating, while the surface coating is illuminated with the first light, to obtain a scan of the surface coating giving colors of the surface coating;
• illuminating a predetermined light spectrum on the coated surface of an area of a predetermined size, wherein quantum dots in the coated surface are excited to luminesce and emit light;
• scanning the coated surface to obtain a quantum dot scan giving colors of the quantum dots;
• filtering the colors of the quantum dots, using the colors of the surface coating, to obtain filtered quantum dot colors;
• and
• processing the filtered quantum dot colors to identify data encoded in the quantum dots;
• determining from the filtered quantum dot colors a number of the quantum dots in said area of the coated surface;
• and
• determining encoded information from said determined number of the quantum dots in said area of the coated surface, including obtaining metadata of the surface coating from hues of the filtered quantum dot colors.