Linear array eye tracker
AssigneeVISX, Incorporated
InventorKingman Yee
Life of this patent
Estimating the term…
Abstract
Improved devices, systems, and methods for sensing and tracking the position of an eye make use of the contrast between the sclera and iris to derive eye position. In many embodiments, linear photodetectors extend across the pupil, optionally also extending across the iris to the sclera. A pair of such linear photodetectors can accurately sense and measure one-dimensional positioning error and provide feedback to a one-dimensional positioning apparatus, resulting in a simple, highly linear system capable of accurate position tracking.
Claims10
A laser eye surgery system for effecting a desired change in optical characteristics of an eye during lateral movements of the eye in X and Y orientations, the eye having a first feature and a second feature with a contrast border therebetween, the system comprising:
- a first linear photodetector having an elongate detector area, the detector area of the first linear photodetector oriented to receive light from the first and second feature of the eye along a first axis extending across the contrast border;
- and
- a second linear photodetector having an elongate detector area, the detector area of the second linear photodetector oriented to receive light from the first and second feature of the eye along a second axis extending across the contrast border, the second axis disposed at an angle relative to the first axis;
- a processor coupled to the first and second linear photodetectors, the processor calculating the lateral movements of the eye in the X and Y orientations in response to the light received from along the first and second axes;
- and
- a laser coupled to the processor, the laser directing a laser beam toward the eye to effect the desired change in optical characteristics of the eye, the beam moving laterally in response to the calculated lateral movements of the eye.
A laser eye surgery method comprising:
- illuminating a first feature and a second feature of an eye;
- measuring light from the illuminated eye with a plurality of linear photodetectors while each linear detector is aligned to receive light from the first feature, from the second feature, and from across a contrast border therebetween;
- determining lateral movements of the eye from the measured light;
- directing a laser beam toward a corneal tissue of the eye to effect a desired change in optical characteristics of the eye;
- and
- moving the beam laterally in response to the lateral movements of the eye.
Dependencies are inferred from the claim text.