Multifunctional metasurface flat optics
Meta-optic systems are described that include multi-function metasurfaces formed from a plurality of meta-atoms. A multi-function metasurface can exhibit two or more different optical functions for two or more different states of light incident on the metasurface. Different states of light include different polarizations, different wavelengths, and different angles of incidence. Different optical functions include distance sensing, converging, diverging, image formation, and patterned light formation. The multi-function metasurface can selectively impart different phase profiles to an incident beam depending on the incident beam's state of light.
1. An optic comprising:
a substrate; and
a metasurface comprising a plurality of meta-atoms disposed on a first side of the substrate and configured to impart a depth-sensitive phase profile to first incident light in a first state and to impart a depth-insensitive phase profile to second incident light in a second state different than the first state, wherein:
each meta-atom of the plurality of meta-atoms is a microfabricated structure disposed on the first side of the substrate, and
the first incident light and the second incident light are detectable by a CCD camera or CMOS imaging array.
2. The optic of claim 1 , wherein the depth-sensitive phase profile is characterized by two foci whose locations vary according to depth and the depth-insensitive phase profile comprises a cubic phase profile.
3. The optic of claim 1 , wherein the first state is a first polarization state and the second state is a second polarization state.
4. The optic of claim 1 , wherein the first state is a first wavelength state and the second state is a second wavelength state.
5. The optic of claim 1 , further comprising:
a second metasurface disposed on a second side of the substrate opposite the first side of the substrate and configured to form an image on an image plane of a scene viewed by the optic.
6. The optic of claim 5 , wherein the image plane is flat.
7. The optic of claim 6 , wherein the second metasurface is configured to direct the first incident light and the second incident light to the image plane.
8. An optical sensing system comprising:
the optic of claim 1 ;
a filter in optical communication with the optic;
a first image sensor in optical communication with the filter to receive the first incident light in the first state and not receive the second incident light in the second state; and
a second image sensor in optical communication with the filter to receive the first incident light in the second state and not receive the first incident light in the first state.
9. An optical sensing system comprising:
the optic of claim 1 ;
a switchable filter in optical communication with the optic; and
an image sensor in optical communication with the optic.
10. The optical sensing system of claim 9 , wherein the switchable filter in a first configuration transmits first light of a first polarization state and suppresses transmission of second light of a second polarization state and in a second configuration transmits the second light of the second polarization state and suppresses transmission of the first light of the first polarization state.
11. The optical sensing system of claim 9 , wherein the switchable filter in a first configuration transmits first light of a first wavelength and suppresses transmission of second light of a second wavelength and in a second configuration transmits the second light of the second wavelength and suppresses transmission of the first light of the first wavelength.
12. The optical sensing system of claim 9 , further comprising:
light emitters configured to illuminate a scene viewed by the optic with light of different polarizations.
13. The optical sensing system of claim 9 , further comprising:
light emitters configured to illuminate a scene viewed by the optic with light of different wavelengths.