Medical devices, systems, and methods for performing eye exams and eye tracking
Apparatus and methods for eye tracking using an optical coherence tomography (OCT) device are disclosed. Such eye tracking may be performed by using information about the shape of the cornea and the corneal apex or using the iris/pupil border obtained using the OCT device.
1. A method of detecting an eye gaze direction or eye position, the method comprising:
performing at least two OCT B scans, each OCT B-scan including at least a portion of an iris and at least a portion of a pupil of an eye;
determining a location of at least three pupillary border points between said iris and said pupil of the eye based on the OCT B-scan;
determining a function based on the at least three pupillary border points, wherein determining a function comprises fitting a function to the at least three pupillary border points; and
calculating an eye gaze vector based on the function.
2. The method of claim 1 , wherein a first OCT scan of the at least two OCT scans detects at least one pupillary border point, and wherein a second OCT scan of the at least two OCT scans detects at least two pupillary border points.
3. The method of claim 1 , wherein the function is a planar function.
4. The method of claim 3 , wherein the planar function is a circle.
5. The method of claim 3 , wherein the eye gaze vector is normal to the planar function.
6. The method of claim 1 , wherein calculating the eye gaze vector comprises calculating a vector along the line of intersection between a plane orthogonal to a first OCT B-scan of the at least two OCT B-scans and a plane orthogonal to a second OCT B-scan of the at least two OCT B-scans.
7. The method of claim 1 , wherein calculating the eye gaze vector comprises calculating a first vector normal to a first line between two pupillary border points along a first OCT B-scan of the at least two OCT B-scans, said first vector lying in the plane of the first OCT B-scan and intersecting said first line at the midpoint of said first line.
8. The method of claim 7 , further comprising calculating a second vector normal to a second line between two pupillary border points along the second OCT B-scan of the at least two OCT B-scans, said second vector lying in the plane of the second OCT B-scan and intersecting said second line at the midpoint of said second line.
9. The method of claim 8 , further comprising calculating a summed eye gaze direction vector by summing the translated first vector and the translated second vector using three-dimensional vector addition.
10. A method of detecting an eye gaze direction or eye position, the method comprising:
performing at least two OCT B-scans, each OCT B-scan including at least a portion of an iris and at least a portion of a pupil of an eye;
determining a location of at least three pupillary border points between said iris and said pupil of the eye based on the OCT B-scan;
determining a function based on the at least three pupillary border points, wherein the function is a planar function; and
calculating an eye gaze vector based on the function.
11. The method of claim 10 , wherein the planar function is a circle.
12. The method of claim 10 , wherein the eye gaze vector is normal to the planar function.
13. The method of claim 10 , wherein calculating the eye gaze vector comprises calculating a vector along the line of intersection between a plane orthogonal to a first OCT B-scan of the at least two OCT B-scans and a plane orthogonal to a second OCT B-scan of the at least two OCT B-scans.
14. The method of claim 10 , wherein calculating the eye gaze vector comprises calculating a first vector normal to a first line between two pupillary border points along a first OCT B-scan of the at least two OCT B-scans, said first vector lying in the plane of the first OCT B-scan and intersecting said first line at the midpoint of said first line.
15. The method of claim 14 , further comprising calculating a second vector normal to a second line between two pupillary border points along the second OCT B-scan of the at least two OCT B-scans, said second vector lying in the plane of the second OCT B-scan and intersecting said second line at the midpoint of said second line.
16. The method of claim 15 , further comprising calculating a summed eye gaze direction vector by summing the translated first vector and the translated second vector using three-dimensional vector addition.
17. The method of claim 10 , wherein a first OCT scan of the at least two OCT scans detects at least one pupillary border point, and wherein a second OCT scan of the at least two OCT scans detects at least two pupillary border points.