Apparatus and method for operating a real time large diopter range sequential wavefront sensor
An wavefront including a light source for providing a light beam to illuminate a subject eye and a beam deflecting to deflect the light beam to compensate transverse movement of the subject eye. A second beam deflecting element scans the beam around a small portion of the retina to dissipate energy.
1. A wavefront sensor comprising:
a light source configured to output a light beam for illumination of a subject eye;
a first beam deflecting element configured to intercept the light beam and direct the light beam toward the subject eye; and
a controller, coupled to the light source and beam deflecting element, configured to control the beam deflecting element to compensate transverse movement of the subject eye.
2. The wavefront sensor of claim 1 further comprising:
an image detector configured to output an image of the subject eye; and
with the controller coupled to the image detector and further configured to process the image to determine the transverse movement of the subject eye.
3. The wavefront sensor of claim 2 with the controller further configured to control the first beam deflecting element to track the transverse movement of the subject eye.
4. The wavefront sensor of claim 1 where the light source is a superluminescent diode.
5. The wavefront sensor of claim 1 where the beam deflecting element is a micro-electromechanical system (MEMS) reflector.
6. The wavefront sensor of claim 1 further comprising:
a second beam deflecting element configured to receive the light beam and direct the light beam toward the subject eye;
and with the controller further configured to control the second beam deflecting element to scan the light beam around a small portion of the retina of the subject eye while controlling the first beam deflecting element to compensate transverse movement of the eye.
7. The wavefront sensor of claim 6 further comprising:
a first focusing element to focus the light beam to a small area;
and with the controller further configured to increase peak power of the light source when the light beam is scanned around the small portion of the retina.
8. The wavefront sensor of claim 1 further comprising:
a second lens having a back focal plane positioned at the first beam deflecting element and configured to direct and focus the light beam to the subject eye so that compensating by the first beam deflecting element does not cause movement of SLD beam on the retina of an emmetropic subject eye.