Fourier ptychographic imaging systems, devices, and methods
Systems, devices, and methods of Fourier ptychographic imaging by computationally reconstructing a high-resolution image by iteratively updating overlapping regions of variably-illuminated, low-resolution intensity images in Fourier space.
1. A Fourier ptychographic imaging method, comprising:
receiving a plurality of variably-illuminated intensity images, each variably-illuminated intensity image captured by a radiation detector while illumination is provided at one of a plurality of incidence angles, wherein all the variably-illuminated intensity images are captured at the same plane; and
reconstructing a complex two-dimensional image from the plurality of variably-illuminated intensity images captured at the same plane by:
(i) inverse Fourier transforming data in a region of a plurality of regions in Fourier space to generate image data, the region corresponding to one incidence angle of the plurality of incidence angles;
(ii) updating the image data by replacing its amplitude with an intensity value from a variably-illuminated intensity image of the plurality of variably-illuminated intensity images captured at the same plane, the variably-illuminated intensity image associated with the corresponding one incidence angle;
(iii) Fourier transforming the updated image data and updating the region in Fourier space with the Fourier transformed updated data; and
(iv) repeating (i)-(iii) for each region of the plurality of regions to generate a solution and inverse transforming the solution to generate the complex two-dimensional image.
2. The Fourier ptychographic imaging method of claim 1 , wherein the reconstruction does not use phase measurements.
3. The Fourier ptychographic imaging method of claim 1 , further comprising prior to (i) using another solution to provide initial data in the plurality of regions in Fourier space.
4. The Fourier ptychographic imaging method of claim 1 , wherein one or more sets of neighboring regions of the plurality of regions in Fourier space overlap.
5. The Fourier ptychographic imaging method of claim 4 , wherein the one or more sets of neighboring regions overlap by about 65% to about 75%.
6. The Fourier ptychographic imaging method of claim 1 , wherein the complex two-dimensional image is of higher resolution than that of the variably-illuminated intensity images.
7. The Fourier ptychographic imaging method of claim 1 , further comprising causing one or more light sources to sequentially illuminate from the plurality of incidence angles and cause the radiation detector to simultaneously capture the plurality of variably-illuminated intensity images.
8. A Fourier ptychographic imaging apparatus, comprising:
one or more light sources configured to sequentially illuminate a specimen being imaged at a plurality of incidence angles;
one or more optical elements comprising at least one lens, the optical elements configured to receive light issuing from the specimen;
a radiation detector configured to capture a plurality of variably-illuminated intensity images at the same plane based on light passed from the one or more optical elements, wherein each variably-illuminated intensity image is captured while the one or more light sources illuminates the specimen at one of the plurality of incidence angles, and wherein all variably-illuminated intensity images are captured at the same plane; and
one or more processors in communication with the radiation detector and/or the one or more light sources, the one or more processors configured to receive the plurality of variably-illuminated intensity images, the one or more processors further configured to:
reconstruct a complex two-dimensional image from the plurality of variably-illuminated intensity images captured at the same plane by:
(i) inverse Fourier transforming data in a region of a plurality of regions in Fourier space to generate image data, the region corresponding to one incidence angle of the plurality of incidence angles;
(ii) updating the image data by replacing its amplitude with an intensity value from a variably-illuminated intensity image of the plurality of variably-illuminated intensity images captured at the same plane, the variably-illuminated intensity image associated with the corresponding one incidence angle;
(iii) Fourier transforming the updated image data and updating the region in Fourier space with the Fourier transformed updated data; and
(iv) repeating (i)-(iii) for each region of the plurality of regions to generate a solution and inverse transforming the solution to generate the complex two-dimensional image.
9. The Fourier ptychographic imaging apparatus of claim 8 , wherein reconstruction does not use phase measurements.
10. The Fourier ptychographic imaging apparatus of claim 8 , wherein the radiation detector comprises a charge coupled device, a CMOS imaging sensor, an avalanche photo-diode array, a photo-diode array, or a photomultiplier tube array.
11. The Fourier ptychographic imaging apparatus of claim 8 , wherein the one or more light sources comprises a liquid crystal display (LCD) or a light emitting diode (LED) matrix.
12. The Fourier ptychographic imaging apparatus of claim 8 , wherein the reconstruction further comprises, prior to (i), using another solution to provide initial data in the plurality of regions in Fourier space.
13. The Fourier ptychographic imaging apparatus of claim 8 , wherein one or more sets of neighboring regions of the plurality of regions in Fourier space overlap.
14. The Fourier ptychographic imaging apparatus of claim 13 , wherein the one or more sets of neighboring regions overlap by about 65% to about 75%.
15. The Fourier ptychographic imaging apparatus of claim 8 , wherein the complex two-dimensional image generated is of higher resolution than that of the variably-illuminated intensity images.
16. The Fourier ptychographic imaging apparatus of claim 8 , wherein the reconstruction further comprises, prior to (i), using another solution to provide initial data in the plurality of regions in Fourier space.
17. The Fourier ptychographic imaging apparatus of claim 8 , wherein the one or more processors are further configured to cause the one or more light sources to sequentially illuminate at the plurality of incidence angles and cause the radiation detector to simultaneously capture the plurality of variably-illuminated intensity images.
18. A Fourier ptychographic imaging method, comprising:
reconstructing a digitally focused complex two-dimensional image from a plurality of variably-illuminated intensity images, each variably-illuminated intensity image captured by a radiation detector while illumination is provided at one of a plurality of incidence angles, wherein all the variably-illuminated intensity images are captured at the same plane, the reconstruction comprising:
(i) iteratively updating data in a plurality of regions in Fourier space, the plurality of regions corresponding to the plurality of incidence angles, wherein each of the regions is updated with Fourier transformed image data having an amplitude based on an intensity value from a variably-illuminated intensity image of the plurality of variably-illuminated intensity images captured at the same plane, the variably-illuminated intensity image associated with a corresponding incidence angle of the plurality of incidence angles; and
(ii) applying one or more digital refocusing operations to generate the digitally focused complex two-dimensional image.
19. The Fourier ptychographic imaging method of claim 18 , wherein the reconstruction does not use phase measurements.
20. The Fourier ptychographic imaging method of claim 18 , wherein (i) and (ii) comprise:
(A) inverse Fourier transforming data in a region of the plurality of regions to generate image data, the region corresponding to one incidence angle of the plurality of incidence angles;
(B) applying a phase factor to the image data;
(C) updating the image data by replacing an amplitude of the image data with the intensity value from the variably-illuminated intensity image associated with the corresponding one incidence angle;
(D) applying an inverse phase factor to the updated image data; and
(E) Fourier transforming the updated image data and updating the region in Fourier space with the Fourier transformed updated data.
21. A Fourier ptychographic imaging apparatus, comprising:
one or more light sources configured to sequentially illuminate a specimen being imaged at a plurality of incidence angles;
one or more optical elements comprising at least one lens, the optical elements configured to receive light issuing from the specimen;
a radiation detector configured to capture a plurality of variably-illuminated intensity images at the same plane based on light passed from the one or more optical elements, wherein all the variably-illuminated intensity images are captured at the same plane, and wherein each variably-illuminated intensity image is captured while the one or more light sources illuminates the specimen at one of the plurality of incidence angles; and
one or more processors in communication with the radiation detector and/or the one or more light sources, the one or more processors configured to reconstruct a digitally focused complex two-dimensional image from the plurality of variably-illuminated intensity images, the reconstruction comprising:
(i) iteratively updating data in a plurality of regions in Fourier space, the plurality of regions corresponding to the plurality of incidence angles, wherein each of the regions is updated with Fourier transformed image data having an amplitude based on an intensity value from a variably-illuminated intensity image of the plurality of variably-illuminated intensity images captured at the same plane, the variably-illuminated intensity image associated with a corresponding incidence angle of the plurality of incidence angles; and
(ii) applying one or more digital refocusing operations to generate the digitally focused complex two-dimensional image.
22. The Fourier ptychographic imaging apparatus of claim 21 , wherein the reconstruction does not use phase measurements.
23. The Fourier ptychographic imaging apparatus of claim 21 , wherein (i) and (ii) comprise:
(A) inverse Fourier transforming data in a region of the plurality of regions to generate image data, the region corresponding to one incidence angle of the plurality of incidence angles;
(B) applying a phase factor to the image data;
(C) updating the image data by replacing an amplitude of the image data with the intensity value from the variably-illuminated intensity image associated with the corresponding one incidence angle;
(D) applying an inverse phase factor to the updated image data; and
(E) Fourier transforming the updated image data and updating the region in Fourier space with the Fourier transformed updated data.
24. The Fourier ptychographic imaging apparatus of claim 21 , wherein the radiation detector comprises a charge coupled device, a CMOS imaging sensor, an avalanche photo-diode array, a photo-diode array, or a photomultiplier tube array.
25. The Fourier ptychographic imaging apparatus of claim 21 , wherein the one or more light sources comprises a liquid crystal display (LCD) or a light emitting diode (LED) matrix.
26. The Fourier ptychographic imaging method of claim 1 , wherein the radiation detector does not move while capturing the plurality of variably-illuminated intensity images.
27. The Fourier ptychographic imaging method of claim 1 , wherein the reconstructed complex two-dimensional image includes phase information recovered by the reconstruction.
28. The Fourier ptychographic imaging method of claim 1 , wherein the radiation detector is stationary.
29. The Fourier ptychographic imaging apparatus of claim 8 , wherein the radiation detector is stationary.
30. The Fourier ptychographic imaging method of claim 18 , wherein the radiation detector is stationary.
31. The Fourier ptychographic imaging apparatus of claim 21 , wherein the radiation detector is stationary.