  We propose a class of optical transformation media, illusion media, which
render the enclosed object invisible and generate one or more virtual objects
as desired. We apply the proposed media to design a microwave device, which
transforms an actual object into two virtual objects. Such an illusion device
exhibits unusual electromagnetic behavior as verified by full-wave simulations.
Different from the published illusion devices which are composed of left-handed
materials with simultaneously negative permittivity and permeability, the
proposed illusion media have finite and positive permittivity and permeability.
Hence the designed device could be realizable using artificial metamaterials.
