Bin sensor

A sensor system for a container, the system comprising:

• an emitter of a detection radiation into the container;
• a receiver of reflected radiation arranged to produce a signal based on received reflected radiation, wherein the received reflected radiation is produced by reflection of contents of the container;
• a processor for interpreting the signal and preparing a transmission signal;
• a transmitter of the transmission signal;
• wherein the emitter, the receiver, the processor and the transmitter are housed within a package that is integrally formed in a moulded plastic hinged lid of the container, with a layer of plastic covering the emitter and receiver, wherein the emitter emits radiation that passes through the layer of plastic, wherein the layer of plastic covering the emitter and the receiver is formed during moulding of the moulded plastic lid so as to be integral with and continuous with the rest of the moulded plastic lid.