Multifocal system using adaptive lenses

1. A device, comprising:

A first lens assembly controllable to switch between a first plurality of optical powers, the first lens assembly comprising a plurality of directly optically coupled lenses, wherein each of the first plurality of optical powers of the first lens assembly for a polychromatic input light is a sum of individual optical powers of the plurality of directly optically coupled lenses;

A second lens assembly controllable to switch between a second plurality of optical powers that are opposite of the first plurality of optical powers; and

A half-wave plate disposed between the first lens assembly and the second lens assembly.

2. The device of claim 1 , wherein the half-wave plate is configured to convert a first light having a first polarization received from the first lens assembly to a second light having a second polarization orthogonal to the first polarization, and output the second light toward the second lens assembly.

3. The device of claim 1 , wherein at least one lens of the plurality of directly optically coupled lenses is switchable between a non-zero optical power state and a zero optical power state.

4. The device of claim 3 , wherein the at least one lens is a circular polarization dependent active liquid crystal (“LC”) lens.

5. The device of claim 1 , wherein the directly optically coupled lenses in the first lens assembly are first lenses, and the second lens assembly comprises a plurality of directly optically coupled second lenses.

6. The device of claim 5 , wherein:

at least one first lens of the plurality of directly optically coupled first lenses is switchable between a non-zero optical power state and a zero optical power state, and

at least one second lens of the plurality of directly optically coupled second lenses is switchable between a non-zero optical power state and a zero optical power state.

7. The device of claim 6 , wherein the at least one first lens and the at least one second lens are circular polarization dependent active LC lenses.

8. The device of claim 6 , wherein the at least one first lens is substantially identical to the at least one second lens.

9. The device of claim 1 , wherein each of the plurality of directly optically coupled lenses is configured to operate as a converging lens for a circularly polarized incident light having a predetermined handedness, and as a diverging lens for a circularly polarized incident light having a handedness that is opposite to the predetermined handedness.

10. The device of claim 1 , wherein the second lens assembly has the same number of lenses as the first lens assembly.

11. The device of claim 1 , wherein each of the first lens assembly and the second lens assembly includes a passive lens with a non-switchable optical power.

12. A method, comprising:

Receiving a first light by a first lens assembly controllable to switch between a first plurality of optical powers, the first lens assembly comprising a plurality of directly optically coupled lenses, wherein each of the first plurality of optical powers of the first lens assembly for a polychromatic input light is a sum of individual optical powers of the plurality of directly optically coupled lenses;

Transmitting, by the first lens assembly, the first light to a half-wave plate disposed between the first lens assembly and a second lens assembly controllable to switch between a second plurality of optical powers that are the opposite of the first plurality of optical powers; and

Converting, by the half-wave plate, the first light intro a second light propagating towards the second lens assembly, the first light and the second light having orthogonal polarizations.

13. The method of claim 12 , further comprising: determining an optical power of the second lens assembly; and determining, based on the determined optical power of the second lens assembly, an optical power for the first lens assembly, wherein the optical power of the first lens assembly is a first optical power, and the optical power of the second lens assembly is a second optical power opposite to the first optical power.

14. The method of claim 13 , further comprising: transmitting, by the first lens assembly having the first optical power, the first light to the half-wave plate; and transmitting, by the second lens assembly having the second optical power, the second light.

15. The method of claim 13 , wherein at least one lens of the plurality of directly optically coupled lenses in the first lens assembly is switchable between a non-zero optical power state and a zero optical power state, and the method further comprises:

configuring an optical state of the at least one first lens to provide the first optical power.

16. The method of claim 15 , wherein the at least one lens is a circular polarization dependent active LC lens.