Apparatus and method for operating a real time large diopter range sequential wavefront sensor
An apparatus including a wavefront sensor including a light source configured to illuminate a subject eye, a detector, an image sensor configured to output an image of the subject eye, a first beam deflecting element configured to intercept a wavefront beam returned from a subject eye when the subject eye is illuminated by the light source and configured to direct a portion of the wavefront from the subject eye through an aperture toward the detector and a controller, coupled to the light source, the image sensor and the beam deflecting element, configured to process the image to determine transverse movement of the subject eye and to control the beam deflecting element to deflect and project through the aperture portions of an annular ring portion of the wavefront and further configured to pulse the light source at a firing rate to sample selected portions of the annular ring at the detector, to process the image of the subject eye to calculate transverse movement of the subject eye and to orient the beam deflecting element at a DC offset angle to compensate transverse movement of the subject eye.
1. A wavefront sensor comprising:
a light source configured to illuminate a subject eye;
a detector;
an image sensor configured to output an image of the subject eye;
a first beam deflecting element configured to intercept a wavefront beam returned from a subject eye when the subject eye is illuminated by the light source and configured to direct a portion of the wavefront from the subject eye through an aperture toward the detector; and
a controller, coupled to the light source, the image sensor and the beam deflecting element, configured to process the image to determine transverse movement of the subject eye and to control the beam deflecting element to deflect and project through the aperture portions of an annular ring portion of the wavefront and further configured to pulse the light source at a firing rate to sample selected portions of the annular ring at the detector, to process the image of the subject eye to calculate transverse movement of the subject eye and to orient the beam deflecting element at a DC offset angle to compensate transverse movement of the subject eye.
2. The wavefront sensor of claim 1 with the controller further configured to increase the pulsing rate to increase sampling density of the annular ring portion.
3. The wavefront sensor of claim 1 with the controller further configured to phase-shift the firing time to angularly shift locations of the portions sampled by the detector.
4. The wavefront sensor of claim 1 with the controller configured to control the beam deflecting element to change the radius of the sampled annular ring portion of the wavefront so that a set of annular rings of different radii are sampled by the detector.
5. The wavefront sensor of claim 1 with the controller configured to control the beam deflecting element to limit radius size according to the diameter of the pupil of the subject eye.
6. The wavefront sensor of claim 1 with the controller configured to control the beam deflecting element to deflect and project the wavefront beam through the aperture portions of a spiral portion of the wavefront, to the detector.
7. The wavefront sensor of claim 1 where the beam deflecting element is a micro-electro-mechanical systems (MEMS) reflector.
8. The wavefront sensor of claim 1 where the beam deflecting element is a rotatable reflecting element.