Nano-optic refractive optics

{
  "publication_number": "US9880393B2",
  "country": "US",
  "kind": "B2",
  "title": "Nano-optic refractive optics",
  "abstract": "A vertical dipole array structure includes a substrate that supports a film, which is not comprised of a negative-index metamaterial. The film includes a plurality of tilt-oriented portions and apertures. At least two of the tilt-oriented portions are separated by an aperture, and the tilt-oriented portions are configured such that incident radiation is redirected into a negative or positive refraction direction.",
  "claims": [
    "1. A vertical dipole array structure comprising (A) a substrate that supports (B) a film comprising a plurality of tilt-oriented portions, wherein (i) said film has a plurality of nanoapertures, (ii) at least two of said tilt-oriented portions are separated by a nanoaperture of the plurality of nanoapertures, (iii) said tilt-oriented portions are configured such that incident radiation is redirected into a negative refraction direction and through the plurality of nanoapertures, and (iv) said film is not comprised of a negative-index metamaterial, wherein the nanoapertures have a width of 40-80 nm, wherein the tilt-oriented portions extend over vertical portions of the array structure such that sidewalls of adjacent tilt-oriented portions are parallel to each other, and the tilt-oriented portions each have a first sidewall and a second sidewall, the first sidewall being opposed in orientation to the second sidewall.",
    "2. The vertical dipole array structure of claim 1, wherein at least two of said tilt-oriented portions are separated by more than one nanoaperture.",
    "3. The vertical dipole array structure of claim 1, wherein the thin film comprises highly conducting material.",
    "4. The vertical dipole array structure of claim 1, wherein the thin film comprises Ag, Au, Al, Cu, Cr, graphene, graphite, or a conducting oxide.",
    "5. The vertical dipole array structure of claim 1, wherein the tilt-oriented portions are tilt-oriented at different angles relative to each other such that a diverging input beam is transmitted as a collimated parallel beam.",
    "6. The vertical dipole array structure of claim 1, wherein the tilt-oriented portions are tilt-oriented at angles such that incident radiation is transmitted through the nanoapertures constructively interferes at a focal point.",
    "7. The vertical dipole array structure of claim 1, wherein the nanoapertures are separated by uniform grating periods.",
    "8. The vertical dipole array structure of claim 1, wherein the nanoapertures are separated by non-uniform grating periods.",
    "9. The vertical dipole array structure of claim 1, wherein the tilt-oriented portions are configured to primarily support-1st order transmission of incident radiation.",
    "10. The vertical dipole array structure of claim 1, wherein a surface of the substrate that supports the film comprises a saw-tooth profile comprising tilt-oriented surfaces separated by at least one vertical-step surface.",
    "11. The vertical dipole array structure of claim 1, wherein a surface of the substrate that supports the film comprises a saw-tooth profile comprising a tilt-oriented surfaces separated by at least one vertical-step surface; and wherein the tilt-oriented surfaces are substantially parallel to each other.",
    "12. The vertical dipole array structure of claim 1, wherein the plurality of nanoapertures define discontinuities of the thin film.",
    "13. The vertical dipole array structure of claim 1, the substrate does not comprise a negative-index metamaterial.",
    "14. The vertical dipole array structure of claim 1, wherein the tilt-oriented portions can be adjusted to be tilt-oriented at different angles.",
    "15. The vertical dipole array structure of claim 1, wherein radiation is transmitted without a mirror-imaging effect.",
    "16. The vertical dipole array structure of claim 1, wherein radiation transmitted through the nanoapertures constructively interferes at a given spot for beam focusing function with spot size smaller than about 0.5λ.",
    "17. The vertical dipole array structure of claim 1, wherein the plurality of nanoapertures are structured to transmit a traverse magnetic polarization component and to block a transverse electric polarization component.",
    "18. The vertical dipole array structure of claim 1, wherein a width of each nanoaperture is 60 nm.",
    "19. A vertical dipole array structure comprising (A) a substrate that supports (B) a film comprising a plurality of tilt-oriented portions, wherein (i) said film has a plurality of nanoapertures, (ii) at least two of said tilt-oriented portions are separated by a nanoaperture of the plurality of nanoapertures, (iii) said tilt-oriented portions are configured such that incident radiation is transmitted through the plurality of nanoapertures and constructively interferes at a focal point, and (iv) said film is not comprised of a negative-index metamaterial, wherein the nanoapertures have a width of 40-80 nm, and wherein the tilt-oriented portions extend over vertical portions of the array structure such that sidewalls of adjacent tilt-oriented portions are parallel to each other, and the tilt-oriented portions each have a first sidewall and a second sidewall, the first sidewall being opposed in orientation to the second sidewall.",
    "20. A vertical dipole array structure comprising (A) substrate that supports (B) a film comprising a plurality of offset portions, wherein (i) said film has a plurality of nanoapertures, (ii) at least two of said offset portions are separated by a nanoaperture, (iii) said offset portions are configured such that incident radiation is redirected into an negative refraction direction and through the plurality of nanoapertures, and (iv) said film is not comprised of a negative-index metamaterial, wherein the nanoapertures have a width of 40-80 nm, wherein the offset portions extend over vertical portions of the array structure such that sidewalls of adjacent offset portions are parallel to each other, and the offset portions each have a first sidewall and a second sidewall, the first sidewall being opposed in orientation to the second sidewall.",
    "21. The vertical dipole array structure of claim 20, wherein a surface of the substrate that supports the film comprises a mesa pattern.",
    "22. A vertical dipole array structure comprising (A) a substrate that supports (B) a film comprising a plurality of tilt-oriented portions, wherein (i) said film has a plurality of nanoapertures, (ii) at least two of said tilt-oriented portions are separated by a nanoaperture, (iii) said tilt-oriented portions are configured such that incident radiation is redirected into a positive or negative refraction direction and through the plurality of nanoapertures, and (iv) said film is not comprised of a negative-index metamaterial, wherein the nanoapertures have a width of 40-80 nm, wherein the vertical dipole array structure is arranged with the plurality of nanoapertures being oriented vertically with respect to the substrate such that the incident radiation is re-radiated into a direction tilted away from a direction normal to the substrate, and wherein the tilt-oriented portions extend over vertical portions of the array structure such that sidewalls of adjacent tilt-oriented portions are parallel to each other, and the tilt-oriented portions each have a first sidewall and a second sidewall, the first sidewall being opposed in orientation to the second sidewall.",
    "23. A vertical dipole array structure comprising (A) a substrate that supports (B) a film comprising a plurality of tilt-oriented portions, wherein (i) said film has a plurality of nanoapertures, (ii) at least two of said tilt-oriented portions are separated by a nanoaperture, (iii) said tilt-oriented portions are configured such that incident radiation is redirected only into a negative refraction direction and through the plurality of nanoapertures, and (iv) said film is not comprised of a negative-index metamaterial, wherein the plurality of nanoapertures are structured to transmit a traverse magnetic polarization component and to block a transverse electric polarization component, and wherein the tilt-oriented portions extend over vertical portions of the array structure such that sidewalls of adjacent tilt-oriented portions are parallel to each other, and the tilt-oriented portions each have a first sidewall and a second sidewall, the first sidewall being opposed in orientation to the second sidewall."
  ],
  "description_excerpt": "The present invention is directed generally to optical devices and more particularly to nanostructured optical devices and methods of making the devices.\n\nRefraction of light at an interface of two different media forms an essential basis in imaging and beam-shaping optics. While commonly viewed as a macroscopic phenomenon occurring at an interface of bulk media, at a microscopic level, the phenomenon involves diffractive transmission of light through atomic or molecular level scatterers (re-radiators) and subsequent interference among the produced wavelets.\n\nAn intrinsic connection is evident between refraction and grating diffraction in that both phenomena involve diffractive transmission and interference. Yet, their differences lie at the vastly different length scales involved. That is, refraction occurs due to the atomic/molecular level spacing of scatterers and grating diffraction occurs due to wavelength scale aperture spacing.\n\nIn the case of an interface with an artificial medium whose refractive index is negative, light can be bent to a negative angle with the surface normal. However, negative-index metamaterials commonly involve resonant structures designed at a sub-wavelength scale, and are intrinsically associated with loss and limited spectral width of operation. Additionally, in conventional gratings, the transmitted power is mostly carried by the 0 th order diffraction (i.e., direct transmission), and other higher-order diffraction is usually of minor intensity. For example, the radiation pattern 12 of the conventional horizontal- dipole array 10 shown in FIG.",
  "cpc": [
    "G02B 27/12",
    "B05D 3/107",
    "B05D 5/06",
    "B82Y 20/00",
    "G02B 2207/101",
    "G02B 5/008",
    "G02B 5/1861",
    "H01L 31/022425",
    "H01L 31/0543",
    "H10F 77/211",
    "H10F 77/484",
    "Y02E 10/52"
  ],
  "ipc": [
    "B05D 3/10",
    "B05D 5/06",
    "G02B 27/12",
    "H01L 31/0224",
    "B82Y 20/00",
    "G02B 5/00",
    "G02B 5/18",
    "H01L 31/054"
  ],
  "assignees": [
    "University of Pittsburgh"
  ],
  "inventors": [
    "Hong Koo Kim",
    "Yun-Suk Jung",
    "Yonggang Xi"
  ],
  "filing_date": "2011-07-21",
  "publication_date": "2018-01-30",
  "grant_date": "2018-01-30",
  "priority_date": "2010-07-22",
  "application_number": "US-201113811079-A",
  "family_id": "45497455",
  "cited_by_count": 4,
  "citations": [
    "JPH0620940A",
    "US6400509B1",
    "JP2002357707A",
    "US20030227415A1",
    "JP2004061796A",
    "US20040090678A1",
    "US20050078374A1",
    "JP2005115176A",
    "US20050161589A1",
    "US20080024873A1",
    "US20070111366A1",
    "US20080185531A1",
    "JP2007223100A",
    "US20070217008A1",
    "CN1866063A",
    "US20080304159A1",
    "WO2009126972A2",
    "WO2010027753A2",
    "CN101692411A"
  ]
}