Embedded pupil function recovery for fourier ptychographic imaging devices
Certain aspects pertain to Fourier ptychographic imaging systems, devices, and methods that implement an embedded pupil function recovery.
1. A method of Fourier ptychographic imaging with embedded pupil function recovery, the method comprising:
(a) receiving image data for a plurality of intensity images of a sample, the intensity images acquired sequentially by a light detector while the sample is being illuminated at different oblique incidence angles and the light detector is receiving light issuing from the illuminated sample through an optical system having a lens;
(b) Fourier transforming the image data;
(c) simultaneously updating a pupil function of the optical system and a sample spectrum, wherein the sample spectrum is updated in overlapping regions with the Fourier-transformed intensity image data, and the overlapping regions correspond to the different oblique illumination angles; and
(d) inverse Fourier transforming the updated sample spectrum to determine an image of the sample having a higher resolution than the plurality of intensity images.
2. The method of claim 1 , wherein each of the overlapping regions has an area corresponding to the numerical aperture of the lens.
3. The method of claim 2 , wherein the lens is an objective lens, wherein the overlapping regions are in the form of circular pupil apertures.
4. The method of claim 3 , wherein the numerical aperture of the lens is in a range between about 0.02 and about 0.13.
5. The method of claim 3 , wherein the numerical aperture of the lens is about 0.08.
6. The method of claim 2 , further comprising calculating an aberration in the optical system using the updated pupil function.
7. The method of claim 6 , further comprising adaptively correcting an incident wavefront based on the calculated aberration.
8. The method of claim 6 , further comprising determining a substantially aberration-free image of the sample using the calculated aberration.
9. The method of claim 6 , further comprising re-focusing the sample using the calculated aberration.
10. The method of claim 2 , wherein adjacent overlapping regions overlap in area by between 20% and 90%.
11. The method of claim 1 , repeating (c) until the updated sample spectrum is self-consistent.
12. A method of Fourier ptychographic imaging with embedded pupil function recovery, the method comprising:
receiving image data for a plurality of intensity images of a sample, the intensity images acquired sequentially by a light detector while the sample is being illuminated at different oblique incidence angles and the light detector is receiving light issuing from the illuminated sample through an optical system having a lens;
Fourier transforming the image data;
simultaneously updating a pupil function of the optical system and a sample spectrum, wherein the sample spectrum is updated in overlapping regions with the Fourier-transformed intensity image data, and the overlapping regions correspond to the different oblique illumination angles; and
calculating an aberration in the optical system using the updated pupil function.
13. The method of claim 12 , further comprising decomposing a phase component of the updated pupil function into coefficients of Zernike polynomials.
14. The method of claim 13 , further comprising determining wavefront aberration based on coefficients of lower order modes of Zernike polynomials.
15. The method of claim 13 , further comprising determining wavefront aberration based on coefficients of or one or more of a mode associated with defocus aberration, a mode associated with a stigmatism in the x-direction, and a mode associated with a stigmatism in one or two directions.
16. The method of claim 13 , further comprising determining coma aberration based on coefficients of one or more modes of Zernike polynomials.
17. The method of claim 12 , further comprising adaptively correcting an incident wavefront based on the calculated aberration.
18. The method of claim 12 , further comprising inverse Fourier transforming the updated sample spectrum to determine an image of the sample having a higher resolution than the plurality of intensity images.
19. The method of claim 18 , further comprising determining a substantially aberration-free image of the sample using the calculated aberration.
20. The method of claim 18 , further comprising: decomposing a phase component of the updated pupil function to determine a coefficient of a mode associated with defocus aberration; calculating defocus aberration from the coefficient; and re-focusing the higher resolution image of the sample using the calculated defocus aberration.
21. A Fourier ptychographic imaging system employing embedded pupil function recovery, comprising: a variable illuminator configured to illuminate a sample being imaged at a plurality of oblique illumination angles; an optical system having an objective lens configured to collect light issuing from the illuminated sample; a radiation detector configured to receive light issuing from the illuminated sample and transmitted by the optical system, and configured to acquire a plurality of intensity images based on the light received; a processor configured to: simultaneously update a pupil function and a separate sample spectrum, wherein the sample spectrum is updated in overlapping regions with the Fourier-transformed intensity image data, and the overlapping regions correspond to the different oblique illumination angles; and calculate an aberration in the optical system using the updated pupil function.
22. The Fourier ptychographic imaging system of claim 20 , further comprising a wavefront modulator configured to adaptively correct an incident wavefront based on the calculated aberration.
23. The Fourier ptychographic imaging system of claim 20 , wherein the objective lens has a numerical aperture between about 0.02 and 0.13.
24. The Fourier ptychographic imaging system of claim 20 , wherein the objective lens has a numerical aperture numerical aperture of about 0.08.
25. The Fourier ptychographic imaging system of claim 20 , wherein the variable illuminator comprises a circular array of discrete light elements.
26. The Fourier ptychographic imaging system of claim 20 , wherein the processor is further configured to decompose a phase component of the updated pupil function into coefficients of Zernike polynomials.
27. The Fourier ptychographic imaging system of claim 25 , wherein the processor is further configured to determine wavefront aberration based on coefficients of or one or more of a mode associated with defocus aberration, a mode associated with a stigmatism in the x- direction, and a mode associated with a stigmatism in one or two directions.
28. The Fourier ptychographic imaging system of claim 25 , wherein the processor is further configured to determine coma aberration based on coefficients of one or more modes of Zernike polynomials.
29. The Fourier ptychographic imaging system of claim 27 , wherein the processor is further configured to determine coma aberration based on coefficients of one or more modes of Zernike polynomials.
30. The Fourier ptychographic imaging system of claim 20 , wherein the processor is further configured to inverse transform the updated sample spectrum to determine an image of the sample, wherein the image has a higher resolution than the captured intensity images.
31. The Fourier ptychographic imaging system of claim 27 , wherein the processor is further configured to determine a substantially aberration-free image of the sample using the calculated aberration.
32. The Fourier ptychographic imaging system of claim 27 , wherein the processor is further configured to:
decompose a phase component of the updated pupil function to determine a coefficient of a mode associated with defocus aberration;
calculate defocus aberration from the coefficient; and
re-focus the higher resolution image of the sample using the calculated defocus aberration.
33. A method of Fourier ptychographic imaging with embedded pupil function recovery, the method comprising:
providing plane wave illumination at a plurality of oblique incidence angles to a sample being imaged;
collecting light issuing from the sample using an optical system having a lens;
acquiring a plurality of intensity images of the sample using a radiation detector;
simultaneously updating a pupil function of the optical system and a separate sample spectrum, wherein the sample spectrum is updated in overlapping regions with Fourier transformed intensity image data, wherein the overlapping regions corresponds to the plurality of oblique incidence angles; and
inverse Fourier transforming the recovered sample spectrum to recover an image with a higher resolution than the acquired intensity images.
34. The method of claim 33 , further comprising determining an aberration from the updated pupil function.
35. The method of claim 34 , further comprising adaptively correcting for the determined aberration using a wavefront modulator.
36. The method of claim 34 , wherein the overlapping regions overlap by between 20% and 90% in area.