Design of open devices based on multi-folded transformation optics

Open devices with homogeneous material parameters are proposed and designed based on multi-folded transformation optics, including open cloak device, open field concentrator and open field amplifying device. In comparison with the previous transformation devices, the proposed open devices possess open windows with compact and embedded structures, providing a flexible approach for remote control or upgrade. The open cloaking devices can hide arbitrarily shaped/sized object in the core region, making it disappeared in visually for the outside viewers, while the open field concentrator can enhance or store EM energy in the core region, and the open field amplifying device can magnify the scattering field of a small object, generating an bigger illusory image with differential material parameter and size. The effectiveness and correctness of the proposed devices are validated by the numerical results obtained based on the commercial finite element software COMSOL Multiphysics. Such scheme is believed to find potential applications in remote controlling with impressive new functions.