Open cloak designed with transformation optics

In this letter, we propose an object independent open cloak design to conceal any object at a distance. The proposed idea is based on the multi-folded transformation optics to provoke the remotely design of a hidden region, which is open to the outer world. Such obtained hidden region has no influence to the outer boundary scattering field; also, no EM waves can penetrate into such hidden region. The simulation results clearly verified the expected cloaking behavior of our proposed device for various hidden object's shapes and types.