Method, device, and system of measuring eye convergence angle

Patent metadata

Field	Value
Publication number	US-11720170-B2
Application number	US-201916727795-A
Country	US
Kind code	B2
Filing date	Dec 26, 2019
Priority date	Dec 26, 2019
Publication date	Aug 8, 2023
Grant date	Aug 8, 2023

Abstract

An electronic device capable of determining an eye convergence angle using a magnetometer sensor is provided. The magnetometer sensor is capable of reporting angle readings in three dimensions that is aligned with an eye gaze direction of each eye of a user. The magnetometer which is incorporated into the device can fit into a human eye like a contact lens and determine the angle of the gaze direction of both eyes with respect to an object within a field of view. By obtaining this eye convergence angle for an object, it is possible to accurately detect depth information. The electronic device also functions as a digital contact lens that can automatically adjust the focal point of the object to provide the user with a clear vision. The electronic device also includes a display that provides the user with additional information about the object.

First claim

The invention claimed is:

1. A method, comprising:
positioning first and second triaxial magnetometers respectfully in front of a first eye and a second eye to synchronize respective movements of the first and second triaxial magnetometers with respective movements of a center of the first eye and a center of the second eye, wherein first and second eye gaze direction vectors extend from the centers of the first and second eye, respectively;
each of the first and second triaxial magnetometers detecting a direction of a magnetic field, having X-axis, Y-axis, and Z-axis components, from the first and second triaxial magnetometers, respectively, to an object within a field of view of the first and second eyes, wherein the X-axis, Y-axis, and Z-axis are orthogonal to each other;
determining the first and second eye gaze direction vectors based on the X-axis, Y-axis, Z-axis components detected by the first and second triaxial magnetometers, respectively; and
calculating an eye convergence angle of the object based on the first and second eye gaze direction vectors.

2. The method of claim 1 , wherein calculating the eye convergence angle of the object includes:
calculating an inner product of the first and second eye gaze direction vectors;
calculating a first absolute value of the first eye gaze direction vector;
calculating a second absolute value of the second eye gaze direction vector; and
calculating the eye convergence angle based on the inner product, the first absolute value, and the second absolute value.

3. The method of claim 1 , wherein positioning the first and second triaxial magnetometers includes:
determining the centers of the first eye and the second eye;
determining a focal point of the first eye and a focal point of the second eye;
calculating a first positional difference between the focal point of the first eye and the center of the first eye indicative of an amount of alignment of the focal point of the first eye and the center of the first eye, and a second positional difference between the focal point of the second eye and the center of the second eye indicative of an amount of alignment of the focal point of the second eye and the center of the second eye; and
determining whether the first positional difference is within an acceptable marginal range indicative of substantial alignment of the focal point of the first eye and the center of the first eye, and determining whether the second positional difference is within an acceptable marginal range indicative of substantial alignment of the focal point of the second eye and the center of the second eye.

4. The method of claim 3 , wherein:
the first and second triaxial magnetometers are parts of first and second electronic devices, respectively;
positioning the first triaxial magnetometer includes automatically moving the first triaxial magnetometer within the first electronic device to compensate for the first positional difference and substantially correspond the focal point of the first eye to the center of the first eye; and
positioning the second triaxial magnetometer includes automatically moving the second triaxial magnetometer within the second electronic device to compensate for the second positional difference and substantially correspond the focal point of the second eye to the center of the second eye.

5. The method of claim 1 , wherein the center of the first eye is at an intersection of a horizontal meridian and a vertical meridian of the first eye, and the center of the second eye is at an intersection of a horizontal meridian and a vertical meridian of the second eye.

6. The method of claim 1 , wherein the first and second triaxial magnetometers are parts of first and second eye-mountable electronic devices, respectively.

7. An eye-mountable electronic device, comprising:
a transparent substrate; and
a first electronic component coupled to the transparent substrate, the first electronic component including:
a processor;
a first magnetic sensor communicatively connected to the processor, the first magnetic sensor configured to detect a direction of a magnetic field, having X-axis, Y-axis, and Z-axis components, from the first magnetic sensor to an object, wherein the X-axis, Y-axis, and Z-axis are orthogonal to each other; and
a transceiver configured to receive sensor data from a second magnetic sensor of another eye-mountable electronic device, the sensor data including a direction of a magnetic field detected by the second magnetic sensor, having X-axis, Y-axis, and Z-axis components, from the second magnetic sensor to the object,
wherein the processor, in operation:
determines a first and second eye gaze direction vectors based on the X-axis, Y-axis, Z-axis components detected by the first and second magnetic sensors, respectively, the first and second eye gaze direction vectors extending from centers of a first and a second eye, respectively; and
calculates an eye convergence angle of the object based on the first and second eye gaze direction vectors.

8. The eye-mountable electronic device of claim 7 , wherein the calculation of the eye convergence angle of the object includes causing the processor, in operation, to:
calculate an inner product of the first and second eye gaze direction vectors;
calculate a first absolute value of the first eye gaze direction vector;
calculate a second absolute value of the second eye gaze direction vector; and
calculate the eye convergence angle based on the inner product, the first absolute value, and the second absolute value.

9. The eye-mountable electronic device of claim 7 , further comprising:
a communication circuit coupled to the processor, the communication circuit configured to provide output of the processor and the first magnetic sensor to an external device communicatively coupled to the communication circuit; and
a power supply, the power supply configured to provide operating voltages to the processor, the first magnetic sensor, and the communication circuit.

10. The eye-mountable electronic device of claim 9 , wherein the power supply includes a rechargeable battery,
wherein the rechargeable battery is configured to automatically recharge itself based on translating kinetic energy created during a movement of the first eye or the second eye to an electrical energy.

11. The eye-mountable electronic device of claim 7 , wherein the first magnetic sensor includes a magnetometer having a measurement capability of at least three axes.

12. The eye-mountable electronic device of claim 7 , wherein the center of the first eye is at an intersection of a horizontal meridian and a vertical meridian of the first eye, and the center of the second eye is at an intersection of a horizontal meridian and a vertical meridian of the second eye.

13. The eye-mountable electronic device of claim 7 , wherein the transparent substrate further includes:
a display portion configured to electronically display information associated with the object.

14. The eye-mountable electronic device of claim 7 , wherein the first magnetic sensor and the second magnetic sensor are mounted in the first eye and the second eye, respectively, and configured to move in synchronization with the centers of the first eye and the second eye, respectively.

15. The eye-mountable electronic device of claim 7 , wherein the transparent substrate includes a contact lens substrate.

16. The eye-mountable electronic device of claim 7 , wherein the first magnetic sensor includes a Hall-effect sensor.

17. A system, comprising:
a first eye-mountable device havi

Assignees

• St Microelectronics Inc

Inventors

• Barbier Dominique Paul

Classifications

• G06F3/013 Primary

  Eye tracking input arrangements (G06F3/015 takes precedence) · CPC title

• G01C3/06

  Use of electric means to obtain final indication · CPC title

• G01C3/14

  with binocular observation at a single point, e.g. stereoscopic type (G01C3/20 takes precedence) · CPC title

• G01C3/22

  using a parallactic triangle with variable angles and a base of fixed length at, near, or formed by the object · CPC title

• G02C7/04

  Contact lenses for the eyes (disinfection or sterilisation of contact lenses A61L12/00) · CPC title