Optical lens compression via transformation optics

Abstract

Transformation optics is widely associated with the design of unconventional electromagnetic devices, such as electromagnetic cloaks or concentrators. However, a wide range of conventional optical devices with potentially advantageous properties can be designed by the transformation optical approach. For example, a coordinate transformation can be introduced that compresses a region of space, resulting in an overall decrease in the thickness of an optical instrument such as a lens. The optical properties of a transformed lens, such as Fresnel reflection or aberration profile, are equivalent to those of the original lens, while the transformed lens and the bounding transformation optical material are thinner than the original lens. This approach to flattening the profile of a lens represents an advantage over the use of a higher dielectric material because it does not introduce greater Fresnel reflections or require a redesign of the basic optic. Though transformation optical media are generally anisotropic, with both electric and magnetic response, it is possible to arrive at a dielectric-only transformation optical distribution for a lens interacting with transverse-magnetic (TM) polarized light. The dielectric-only distribution can be implemented using broad-band, low-loss metamaterials. Lens designs for both a full transformation and a dielectric-only implementation are discussed and confirmed via finite-element simulations.

Magnetic superlens-enhanced inductive coupling for wireless power transfer

“…Based on transformation optics theory, the permeability tensor required to implement a reduction in the slab profile from L to L=a is [l x , l y , l z ] ¼ [Àa, Àa, À1=a] in order to reduce the lens thickness from L 0 to L 0 =a. 38 We performed a parametric study, where a sweeps from 0.6 to 2 and the lens thickness L ¼ D= (1 þ a) varies from 0.625D to 0.33D. A constant imaginary part Im(l) ¼ 0.001 has been added to all three components of the slab permeability.…”

Transformation Optics Methodology for Changing the Appearance of an Object

“…And the metric tensors of the transformed space that contains the desired electromagnetic properties can also be derived simultaneously [3][4][5]. Transformation optics has become a fundamental tool for exploring a diverse set of devices with novel properties, such as cloaks [6,7], concentrators [8], lenses [9][10][11][12], waveguide bends and transitions [13][14][15][16][17], antennas [18][19][20][21][22][23][24][25][26], and so on. Generally speaking, the generated materials are inhomogeneous and anisotropic by transformation optics methodology.…”

Flattening of conic reflectors via a transformation method

“…Although the initial application of this theory is in designing invisibility cloaks [2,4], a wide range of unconventional optical and electromagnetic (EM) devices have also been proposed based on this concept. For example, Chen et al designed field rotators in which the incident EM wave shall rotate a certain angle to appear as coming from a different direction [5,6]; Luo et al designed field concentrators which can make the power flow of the incident wave concentrated within a given region [6][7][8][9]; besides, several kinds of superlenses [10][11][12][13][14] have also been proposed by researchers. Based on the transformation optics, this paper proposes a general and rigorous method to tailor a class of reflectors which will have the same optical properties as a conic reflector-that is, parabolic, hyperbolic, or elliptic reflector-while maintaining planar profiles.…”