Identity authentication using lens features

1. A method performed by one or more data processing apparatus, the method comprising:

obtaining at least one image depicting a reflection of light from a lens that is included in a set of eyeglasses of a user;

determining, based on the reflection of light from the lens and a reflection of light from a cornea of the user, a set of features characterizing the lens, comprising:

determining a first focal length that causes the reflection of the light from the lens to be substantially in focus;

determining a second focal length that causes the reflection of the light from the cornea to be substantially in focus; and

determining one or more features characterizing the lens based on a difference between the first focal length and the second focal length; and

determining an identity of the user based at least in part on the set of features characterizing the lens.

2. The method of claim 1 , wherein determining, based on the reflection of light from the lens and the reflection of light from the cornea of the user, the set of features characterizing the lens further comprises:

determining a third focal length that causes the reflection of light from the cornea to be substantially in focus except along a particular axis;

determining a fourth focal length that causes the reflection of light from the cornea to be substantially out of focus except along the particular axis; and

determining one or more features characterizing the lens based on a difference between the third focal length and the fourth focal length.

3. The method of claim 1 , wherein determining the identity of the user based at least in part on the set of features characterizing the lens comprises:

determining that a difference between: (i) the set of features characterizing the lens, and (ii) a template set of features determined during an enrollment process, satisfies a threshold condition; and

in response to determining that the difference satisfies the threshold condition, determining the identity of the user based on one or more additional features characterizing the identity of the user.

4. The method of claim 1 , wherein the light comprises a predetermined pattern of light projected from one or more light sources.

5. The method of claim 1 , wherein determining the set of features characterizing the lens further comprises:

determining a geometry of the reflection of light from the lens; and

determining one or more features characterizing the lens based on the geometry of the reflection of the light from the lens.

6. The method of claim 5 , wherein determining the geometry of the reflection of the light from the lens comprises:

identifying: (i) a first reflection of the light from an outer surface of the lens, and (ii) a second reflection of the light from an inner surface of the lens; and

determining: (i) a first geometry of the first reflection of the light from the outer surface of the lens, and (ii) a second geometry of the second reflection of the light from the inner surface of the lens.

7. The method of claim 6 , wherein determining the one or more features characterizing the lens comprises:

determining one or more features based on a difference between the first geometry and the second geometry.

8. The method of claim 7 , wherein determining the one or more features based on a difference between the first geometry and the second geometry comprises:

determining the one or more features based on a measure of distortion between the first geometry and the second geometry.

9. The method of claim 7 , wherein determining the one or more features based on a difference between the first geometry and the second geometry comprises:

determining the one or more features based on a difference in size between the first geometry and the second geometry.

10. The method of claim 1 , wherein the set of features characterize properties of the lens comprising one or more of: a spherical power of the lens, a cylindrical power of the lens, a cylindrical angle of the lens, a coating of the lens, a tint of the lens, a curvature of an inner surface of the lens, and a curvature of an outer surface of the lens.

11. A system comprising:

one or more computers; and

one or more storage devices communicatively coupled to the one or more computers, wherein the one or more storage devices store instructions that, when executed by the one or more computers, cause the one or more computers to perform operations comprising:

obtaining at least one image depicting a reflection of light from a lens that is included in a set of eyeglasses of a user;

determining, based on the reflection of light from the lens and a reflection of light from a cornea of the user, a set of features characterizing the lens, comprising:

determining a first focal length that causes the reflection of the light from the lens to be substantially in focus;

determining a second focal length that causes the reflection of the light from the cornea to be substantially in focus; and

determining one or more features characterizing the lens based on a difference between the first focal length and the second focal length; and

determining an identity of the user based at least in part on the set of features characterizing the lens.

12. The system of claim 11 , wherein determining, based on the reflection of light from the lens and the reflection of light from the cornea of the user, the set of features characterizing the lens further comprises:

determining a third focal length that causes the reflection of light from the cornea to be substantially in focus except along a particular axis;

determining a fourth focal length that causes the reflection of light from the cornea to be substantially out of focus except along the particular axis; and

determining one or more features characterizing the lens based on a difference between the third focal length and the fourth focal length.

13. The system of claim 11 , wherein determining the identity of the user based at least in part on the set of features characterizing the lens comprises:

determining that a difference between: (i) the set of features characterizing the lens, and (ii) a template set of features determined during an enrollment process, satisfies a threshold condition; and

in response to determining that the difference satisfies the threshold condition, determining the identity of the user based on one or more additional features characterizing the identity of the user.

14. One or more non-transitory computer storage media storing instructions that when executed by one or more computers cause the one or more computers to perform operations comprising:

obtaining at least one image depicting a reflection of light from a lens that is included in a set of eyeglasses of a user;

determining, based on the reflection of light from the lens and a reflection of light from a cornea of the user, a set of features characterizing the lens, comprising:

determining a first focal length that causes the reflection of the light from the lens to be substantially in focus;

determining a second focal length that causes the reflection of the light from the cornea to be substantially in focus; and

determining one or more features characterizing the lens based on a difference between the first focal length and the second focal length; and

determining an identity of the user based at least in part on the set of features characterizing the lens.

15. The non-transitory computer storage media of claim 14 , wherein determining, based on the reflection of light from the lens and the reflection of light from the cornea of the user, the set of features characterizing the lens further comprises:

determining a third focal length that causes the reflection of light from the cornea to be substantially in focus except along a particular axis;

determining a fourth focal length that causes the reflection of light from the cornea to be substantially out of focus except along the particular axis; and

determining one or more features characterizing the lens based on a difference between the third focal length and the fourth focal length.

16. The non-transitory computer storage media of claim 14 , wherein determining the identity of the user based at least in part on the set of features characterizing the lens comprises:

determining that a difference between: (i) the set of features characterizing the lens, and (ii) a template set of features determined during an enrollment process, satisfies a threshold condition; and

in response to determining that the difference satisfies the threshold condition, determining the identity of the user based on one or more additional features characterizing the identity of the user.

17. The non-transitory computer storage media of claim 14 , wherein the light comprises a predetermined pattern of light projected from one or more light sources.

18. A method performed by one or more data processing apparatus, the method comprising:

obtaining at least one image depicting a reflection of light from a lens that is included in a set of eyeglasses of a user;

determining, based on the reflection of light from the lens and a reflection of light from a cornea of the user, a set of features characterizing the lens, comprising:

determining a first focal length that causes the reflection of light from the cornea to be substantially in focus except along a particular axis;

determining a second focal length that causes the reflection of light from the cornea to be substantially out of focus except along the particular axis; and

determining one or more features characterizing the lens based on a difference between the first focal length and the second focal length; and

determining an identity of the user based at least in part on the set of features characterizing the lens.

19. One or more non-transitory computer storage media storing instructions that when executed by one or more computers cause the one or more computers to perform operations comprising:

obtaining at least one image depicting a reflection of light from a lens that is included in a set of eyeglasses of a user;

determining, based on the reflection of light from the lens and a reflection of light from a cornea of the user, a set of features characterizing the lens, comprising:

determining a first focal length that causes the reflection of light from the cornea to be substantially in focus except along a particular axis;

determining a second focal length that causes the reflection of light from the cornea to be substantially out of focus except along the particular axis; and

determining one or more features characterizing the lens based on a difference between the first focal length and the second focal length; and

determining an identity of the user based at least in part on the set of features characterizing the lens.

20. A system comprising:

one or more computers; and

one or more storage devices communicatively coupled to the one or more computers, wherein the one or more storage devices store instructions that, when executed by the one or more computers, cause the one or more computers to perform operations comprising:

obtaining at least one image depicting a reflection of light from a lens that is included in a set of eyeglasses of a user;

determining, based on the reflection of light from the lens and a reflection of light from a cornea of the user, a set of features characterizing the lens, comprising:

determining a first focal length that causes the reflection of light from the cornea to be substantially in focus except along a particular axis;

determining a second focal length that causes the reflection of light from the cornea to be substantially out of focus except along the particular axis; and

determining one or more features characterizing the lens based on a difference between the first focal length and the second focal length; and

determining an identity of the user based at least in part on the set of features characterizing the lens.