Ultra-wide field-of-view flat optics

Patent metadata

Field	Value
Publication number	US-10979635-B2
Application number	US-202016894945-A
Country	US
Kind code	B2
Filing date	Jun 8, 2020
Priority date	Aug 8, 2019
Publication date	Apr 13, 2021
Grant date	Apr 13, 2021

Abstract

Wide-angle optical functionality is beneficial for imaging and image projection devices. Conventionally, wide-angle operation is attained by a complicated assembly of optical elements. Recent advances have led to meta-surface lenses or meta-lenses, which are ultra-thin planar lenses with nanoantennas that control the phase, amplitude, and/or polarization of light. Here, we present a meta-lens capable of diffraction-limited focusing and imaging over an unprecedented >170° angular field of view (FOV). The lens is integrated on a one-piece flat substrate and includes an aperture on one side and a single meta-surface on the other side. The meta-surface corrects third-order Seidel aberrations, including coma, astigmatism, and field curvature. The meta-lens has a planar focal plane, which enables considerably simplified system architectures for imaging and projection. The meta-lens design is generic and can be readily adapted to different meta-atom geometries and wavelength ranges to meet diverse application demands.

First claim

The invention claimed is:

1. An optical component comprising:
a substrate;
an opaque layer on a first side of the substrate, the opaque layer defining an aperture to transmit light over a field of view of at least 120°; and
a meta-surface, on a second side of the substrate opposite the first side, to focus the light transmitted by the aperture through the substrate,
wherein the meta-surface comprises an array of at least 1000×1000 meta-atoms.

2. The optical component of claim 1 , wherein the substrate is planar.

3. The optical component of claim 1 , wherein the substrate is curved.

4. The optical component of claim 1 , wherein the substrate has a thickness t sub and a refractive index at a wavelength of the light of n sub , the aperture has a diameter of D in , and the meta-surface has a diameter D meta =D in +t sub tan[sin −1 (1/n sub )].

5. The optical component of claim 1 , wherein the meta-surface is configured to focus the light incident over all of the field of view to a focal plane parallel to the second side of the substrate.

6. The optical component of claim 5 , further comprising:
a detector array, in the focal plane, to detect the light focused by the meta-surface.

7. The optical component of claim 5 , further comprising:
a light source array in the focal plane, and
wherein the meta-surface is configured to collimate a beam emitted by the light source array and the aperture is configured to emit the beam.

8. The optical component of claim 7 , wherein the meta-surface and/or the aperture are further configured to modulate the beam emitted by the light source array.

9. The optical component of claim 1 , wherein the meta-surface is configured to focus the light incident over all of the field of view with a Strehl ratio of at least 80%.

10. The optical component of claim 1 , wherein the meta-surface is a first meta-surface, and further comprising:
a second meta-surface, disposed in at least a portion of the aperture, to modulate and/or filter the light transmitted by the aperture.

11. The optical component of claim 10 , wherein the second meta-surface is configured to modulate the light transmitted by the aperture with a spatial modulation pattern that depends on an angle of incidence of the light transmitted by the aperture.

12. An optical component comprising:
a substrate;
an opaque layer on a first side of the substrate, the opaque layer defining an aperture to transmit light over a field of view of at least 120°; and
a meta-surface, on a second side of the substrate opposite the first side, to focus the light transmitted by the aperture through the substrate,
wherein the meta-surface has different yet continuous portions configured to capture input beams at different angles of incidence.

13. An optical component comprising:
a substrate;
an opaque layer on a first side of the substrate, the opaque layer defining an aperture to transmit light over a field of view of at least 120°; and
a meta-surface, on a second side of the substrate opposite the first side, to focus the light transmitted by the aperture through the substrate,
wherein the meta-surface is configured to correct at least one third-order Seidel aberration.

14. A method comprising:
transmitting light over a field of view of at least 120° through an aperture formed on a first side of a substrate; and
focusing the light with a meta-surface on a second side of the substrate opposite the first side, wherein focusing the light comprises correcting at least one third-order Seidel aberration.

15. The method of claim 14 , wherein focusing the light comprises focusing the light incident over all of the field of view to a focal plane parallel to the second side of the substrate.

16. The method of claim 15 , further comprising:
detecting the light focused by the meta-surface with a detector array in the focal plane.

17. The method of claim 15 , further comprising:
collimating a beam emitted by the light source array in the focal plane with the meta-surface; and
emitting the beam through the aperture.

18. The method of claim 14 , wherein focusing the light comprises focusing the light incident over all of the field of view with a Strehl ratio of at least 80%.

19. The method of claim 14 , further comprising:
modulating at least of a phase, an amplitude, a polarization, or a wavelength of the light transmitted by the aperture with another meta-surface disposed in at least a portion of the aperture based on an angle of incidence of the light transmitted by the aperture.

20. The method of claim 14 , further comprising:
filtering the light transmitted by the aperture with another meta-surface disposed in at least a portion of the aperture.

21. A sensor comprising:
a substrate;
a light source array, supported by a first portion of the substrate, to emit light;
a first meta-lens, in optical communication with the light source array, to project the light emitted by the light source array toward an object over a field of view of at least about 120°, the first meta-lens comprising a first planar substrate having a first meta-surface on a first side facing the light source array and a first aperture on a second side;
a second meta-lens, in optical communication with the object, to collect the light scattered and/or reflected by the object over a field of view of at least about 120°, the second meta-lens comprising a second planar substrate having a second aperture on a first side facing the object and a second meta-surface on a second side; and
a detector array, supported by a second portion of the substrate and in optical communication with the second meta-lens, to detect the light collected by the second meta-lens.

Assignees

• Massachusetts Inst Technology

Inventors

• Hu Juejun
• Gu Tian
• Shalaginov Mikhail

Classifications

• H04N23/698 Primary

  for achieving an enlarged field of view, e.g. panoramic image capture · CPC title

• G02B6/0023

  provided by one optical element, or plurality thereof, placed between the light guide and the light source, or around the light source · CPC title

• G02B13/06 Primary

  Panoramic objectives; So-called "sky lenses" {including panoramic objectives having reflecting surfaces} · CPC title

• G02B27/0172

  characterised by optical features · CPC title

• G02B1/002 Primary

  made of materials engineered to provide properties not available in nature, e.g. metamaterials · CPC title