Method, device, and system of measuring eye convergence angle

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.

A system, comprising:

• a first eye-mountable device having a first triaxial magnetometer configured to be mounted on a first eye;
• a second eye-mountable device having a second triaxial magnetometer configured to be mounted on a second eye, wherein each of the first and second triaxial magnetometer are configured to detect a direction of a magnetic field, having X-axis, Y-axis, and Z-axis components, wherein the X-axis, Y-axis, and Z-axis are orthogonal to each other;
• and
• a processor communicatively coupled to the first and second eye-mountable devices,
• wherein the processor, in operation,
• determines first and second eye gaze direction vectors that extend from centers of the first and second eyes, respectively, the first and second eye gaze direction vectors being determined based on the X-axis, Y-axis, Z-axis components detected by the first and second triaxial magnetometers, respectively;
• and
• calculates an eye convergence angle of an object based on the first and second eye gaze direction vectors.