Tracking movement of an eye within a tracking range

1. A system for tracking movement of an eye, comprising:

a camera system configured to generate a plurality of digital images of the eye;

a computer system comprising:

a memory configured to store the plurality of digital images and store at least one of the digital images as a reference image; and

one or more processors configured to:

locate a reference central point of the eye and one or more reference eye features in the reference image;

locate a current central point of the eye and one or more current eye features in a current image of the plurality of images;

track rotational movement of the eye within a tracking range by tracking the reference central point of the eye with the current central point of the eye and comparing the one or more reference eye features with the one or more current eye features and determining a rotational movement of the eye from the comparison of the one or more current eye features of the current image and the one or more reference eye features of the reference image, the tracking range having one or more alert points; and

determine a rotational orientation of the eye relative to at least one alert point of the tracking range; and

an output device configured to output a range indicator that indicates the rotational orientation of the eye relative to the at least one alert point of the tracking range.

2. The system of claim 1 , wherein the output device comprises a display that shows the range indicator as a graphical element.

3. The system of claim 2 , wherein the graphical element comprises:

a linear element representing the tracking range, the linear element having at least one alert point element representing the at least one alert point of the tracking range; and

a slider element corresponding to the eye, the position of the slider relative to the alert point element representing the rotational orientation of the eye relative to the at least one alert point of the tracking range.

4. The system of claim 2 , wherein the graphical element comprises:

a linear element representing the tracking range, the linear element having at least one alert point element representing the at least one alert point of the tracking range; and

an arrow element corresponding to the eye, the position where the arrow points relative to the alert point element representing the rotational orientation of the eye relative to the at least one alert point of the tracking range.

5. The system of claim 2 , wherein the graphical element changes continuously from a first color to a second color to indicate a change in the rotational orientation of the eye relative to the at least one alert point of the tracking range.

6. The system of claim 2 , wherein the graphical element changes continuously from a first shape to a second shape to indicate a change in the rotational orientation of the eye relative to the at least one alert point of the tracking range.

7. The system of claim 2 , wherein the graphical element changes continuously from a first size to a second size to indicate a change in the rotational orientation of the eye relative to the at least one alert point of the tracking range.

8. The system of claim 2 , wherein the graphical element shows a first number that continuously changes to a second number to indicate a change in the rotational orientation of the eye relative to the at least one alert point of the tracking range.

9. The system of claim 2 , wherein the graphical element shows a first word that changes to a second word to indicate a change in the rotational orientation of the eye relative to the at least one alert point of the tracking range.

10. The system of claim 1 , wherein the output device comprises a speaker that emits the range indicator as a sound.

11. The system of claim 10 , wherein the speaker emits a sound that continuously changes in frequency to indicate a change in the rotational orientation of the eye relative to the at least one alert point of the tracking range.

12. The system of claim 10 , wherein the speaker emits a sound that continuously changes in volume to indicate a change in the rotational orientation of the eye relative to the at least one alert point of the tracking range.

13. The system of claim 10 , wherein the speaker emits words to indicate a change in the rotational orientation of the eye relative to the at least one alert point of the tracking range.

14. The system of claim 1 , wherein the image processing system receives a selection of an alert point of the one or more alert points from user input.

15. The system of claim 1 , further comprising a laser system configured to:

receive a notification of the movement of the eye; and

change a laser beam position in response to the notification.

16. A method for tracking the movement of an eye, comprising:

generating a plurality of images of the eye;

storing the plurality of images and at least one of the images as a reference image; and

locating a reference central point of the eye and one or more reference eye features in the reference image;

locating a current central point of the eye and one or more current eye features in a current image of the plurality of images;

tracking rotational movement of the eye within a tracking range by tracking the reference central point of the eye with the current central point of the eye and comparing the one or more reference eye features with the one or more current eye features and determining a rotational movement of the eye from the comparison of the one or more current eye features of the current image and the one or more reference eye features of the reference image, the tracking range having one or more alert points; and

determining a rotational orientation of the eye relative to at least one alert point of the tracking range; and

outputting a range indicator that indicates the rotational orientation of the eye relative to the at least one alert point of the tracking range.