This web site seeks to give a non-technical, intuitive introduction to the quantum theory of the light field. Recent measurement data is employed to illuminate abstract quantum mechanical concepts such as the uncertainty relation, the wave packet, quantum noise, Wigner function, squeezed states, density matrices, etc., using the concrete example of the freely propagating light field.

The web site includes a Java animation illustrating common quantum states of the light field, showing their experimentally measured quantum noise distribution and the corresponding motion of their wave packet.