Compact adaptive optic-optical coherence tomography system
View Patent ↗Badal Optometer and rotating cylinders are inserted in the AO-OCT to correct large spectacle aberrations such as myopia, hyperopic and astigmatism for ease of clinical use and reduction. Spherical mirrors in the sets of the telescope are rotated orthogonally to reduce aberrations and beam displacement caused by the scanners. This produces greatly reduced AO registration errors and improved AO performance to enable high order aberration correction in a patient eyes.
1. An apparatus, comprising:
a light source for providing an input beam;
means for splitting said input beam into a reference beam and an input sample beam;
a Badal optometer configured for adjusting the focus of said input sample beam into the eye of a patient, wherein a portion of said input sample beam reflected from said eye will produce an output sample beam having an optical axis;
a pair of cylindrical lenses positioned to rotate on said optical axis and configured to compensate for at least a portion of astigmatism in said output sample beam to produce an astigmatism compensated output sample beam;
a reference beam path configured to produce an output reference beam that has traveled the same distance as said input sample beam combined with said astigmatism compensated output sample beam; and
means for combining said output reference beam and said astigmatism compensated output sample beam to produce a combined output beam.
2. The apparatus of claim 1 , further comprising a first scanning mirror configured to scan said input sample beam in a first direction at said eye and a second scanning mirror configured to scan said input sample beam in a second direction at said eye, wherein said second direction is about orthogonal to said first direction.
3. The apparatus of claim 2 , wherein said input sample beam travels in a first plane from said means for splitting to said first scanning mirror, wherein said input sample beam travels in a second plane from said first scanning mirror to said second scanning mirror, wherein said second plane is at an angle with respect to said first plane, wherein said angle is selected to remove a portion of system astigmatism from said sample beam.
4. The apparatus of claim 3 , wherein said input sample beam travels in a third plane from said second scanning mirror to said eye, wherein said third plane is about parallel to said first plane.
5. The apparatus of claim 2 , wherein said astigmatism compensated output sample beam comprises a wavefront, said apparatus further comprising a micro-electro-mechanical system (MEMS) deformable mirror (DM) and a wavefront sensor, wherein said MEMS DM is positioned to reflect said astigmatism compensated output sample beam, wherein said wavefront sensor is positioned to sense said wavefront, wherein said wavefront sensor is operatively connected to said MEMS DM to adjust said wavefront.
6. The apparatus of claim 5 , wherein said MEMS DM is not located between said eye and either of said first scanning mirror or said second scanning mirror.
7. The apparatus of claim 2 , further comprising, between said first scanning mirror and said second scanning mirror, a first relay mirror and a second relay mirror, wherein said second relay mirror is tilted orthogonally with respect to said first relay mirror.
8. The apparatus of claim 2 , wherein said eye comprises an entrance pupil, wherein said first scanning mirror and said second scanning mirror are separated by a relay telescope designed to make them optically conjugate to each other and to said entrance pupil of said eye.
9. The apparatus of claim 1 , wherein said input sample beam travels in a first plane and a second plane, wherein said second plane is at an angle with respect to said first plane, wherein said angle is selected to remove a portion of system astigmatism from said sample beam.
10. The apparatus of claim 1 , wherein said output sample beam comprises a retinal image.
11. The apparatus of claim 1 , wherein said eye comprises an entrance pupil, wherein said pair of rotating cylinders are placed at a conjugate plane of said entrance pupil.
12. A method, comprising:
providing an input beam;
splitting said input beam into a reference beam and an input sample beam;
adjusting, with a Badal optometer, the focus of said input sample beam into the eye of a patient, wherein a portion of said input sample beam reflected from said eye will produce an output sample beam having an optical axis;
compensating, with a pair of cylindrical lenses positioned to rotate on said optical axis, for at least a portion of astigmatism in said output sample beam to produce an astigmatism compensated output sample beam;
producing an output reference beam that has traveled the same distance as said input sample beam combined with said astigmatism compensated output sample beam; and
combining said output reference beam and said astigmatism compensated output sample beam to produce a combined output beam.
13. The method of claim 12 , further comprising scanning said input sample beam in a first direction at said eye and in a second direction at said eye, wherein said second direction is about orthogonal to said first direction.
14. The method of claim 12 , further comprising propagating said input sample beam in a first plane and a second plane, wherein said second plane is at an angle with respect to said first plane, wherein said angle is selected to remove a portion of system astigmatism from said sample beam.
15. The method of claim 12 , wherein said astigmatism compensated output sample beam comprises a wavefront, said method further comprising positioning a micro-electro-mechanical system (MEMS) deformable mirror (DM) to reflect said astigmatism compensated output sample beam, said method further comprising positioning a wavefront sensor to sense said wavefront, wherein said wavefront sensor is operatively connected to said MEMS DM to adjust said wavefront.
16. The method of claim 15 , wherein said MEMS DM is not located between said eye and either of said first scanning mirror or said second scanning mirror.
17. The method of claim 12 , wherein said output sample beam comprises a retinal image.
18. The method of claim 12 , wherein said eye comprises an entrance pupil, wherein the step of scanning is carried out with a first scanning mirror and a second scanning mirror that are separated by a relay telescope designed to make them optically conjugate to each other and to said entrance pupil of said eye.
19. The method of claim 12 , wherein said eye comprises an entrance pupil, wherein said pair of cylindrical lenses are placed at a conjugate plane of said entrance pupil.