Phase angle controlled stationary elements for wavefront engineering of electromagnetic radiation
US6768666B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Aug 23, 2002 |
| Grant date | Jul 27, 2004 |
| Priority date | — |
| Expiry date | Aug 23, 2022 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02F2203/18
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A reconfigurable and stationary element for the engineering of the wavefront of electromagnetic radiation. The element includes a phase change material that may be reversibly transformed between its crystalline and amorphous states. By forming a gradient in crystallinity, a phase taper may be stored in the phase change material of the instant element. The phase taper provides control of the phase angle of reflected or reradiated electromagnetic radiation. An incident wavefront of electromagnetic radiation interacts with the instant element and is reradiated with controlled propagation characteristics imposed by the stored phase taper. The instant element may provide non-specular reflection, beam steering, focusing, defocusing, symmetrical and asymmetrical cross section effects, and wavefront correction. In a preferred embodiment, a pattern of amorphous marks is formed within a crystalline matrix of phase change material. By controlling the size, shape, spacing, symmetry and distribution of marks, crystallinity gradients of various strengths in one or more directions may be formed to provide phase tapers that effect the engineering of wavefronts. An apparatus for forming patterns of…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.