Sparse sampling and reconstruction for electron and scanning probe microscope imaging

1. A method for conducting electron or scanning probe microscopy, the method comprising:

driving an electron beam or probe to scan across a sample and visit a subset of pixel locations of the sample that are randomly or pseudo-randomly designated;

determining actual pixel locations on the sample that are visited by the electron beam or probe; and

processing data collected by detectors from the visits of the electron beam or probe at the actual pixel locations and recovering a reconstructed image of the sample.

2. The method of claim 1 , wherein the driving of the electron beam is performed by electrostatic or electromagnetic scan coils.

3. The method of claim 2 , wherein the determining of the actual pixel locations is based on results of modeling dynamics of the scan coils.

4. The method of claim 3 , further comprising modeling the dynamics of the scan coils by:

commanding a stepwise jump in position from one extreme of an electron beam or probe scan range to a second extreme in a calibration routine;

during the stepwise jump of the electron beam or probe, recording output of a detector;

comparing the recorded output of the detector with output recorded during a raster scan of the calibration sample; and

plotting a beam location corresponding to the recorded output of the detector as a function of time.

5. The method of claim 3 , wherein the modeling dynamics is based on at least a 5th-order dynamical model of the scan coils to determine the actual location of the probe or beam as a function of time.

6. The method of claim 1 , wherein the desired pixel locations are not the same as the actual pixel locations.

7. The method of claim 1 , wherein the electron beam or probe is driven electromagnetically or electrostatically.

8. The method of claim 1 , further comprising recovering the reconstructed image of the sample by using a basis pursuit recovery algorithm utilizing compressibility of the acquired data for recovering the reconstructed image.

9. The method of claim 1 , wherein the beam or probe continuously samples as it is in transit to a next pixel location of the subset of pixel locations.

10. The method of claim 1 , wherein the samples are distributed across multiple pixel locations as the beam or probe is in transit to a next pixel location of the subset of pixel locations.

11. The method of claim 1 , wherein the sample is sensitive to overdosing.

12. An electron microscope imaging system comprising:

a processor; and

a computer-readable memory that comprises a plurality of components that are executed by the processor, the plurality of components comprising:

a command component configured to command an electron beam or probe to scan across a sample area and visit a subset of pixel locations of the sample area, the subset of pixel locations being randomly or pseudo-randomly designated;

a determiner component configured to determine actual pixel locations on the sample area that are visited by the electron beam or probe; and

a reconstruction component configured to process data collected by detectors from the visits of the electron beam or probe at the actual pixel locations and recover a reconstructed image from the processed data.

13. The electron microscope imaging system of claim 12 , wherein the reconstruction component is executed by a distributed series of processors.

14. The electron microscope imaging system of claim 12 , wherein the command component instructs the electron beam or probe to sample one half or fewer pixel locations.

15. The electron microscope imaging system of claim 12 , wherein the reconstruction component is configured to recover the reconstructed image of the sample by using a basis pursuit recovery algorithm utilizing compressibility of the acquired data for recovering the reconstructed image.

16. The electron microscope imaging system of claim 12 , wherein the command component is configured to command the beam or probe to continuously sample as the beam or probe is in transit to a next pixel location of the subset of pixel locations.

17. The electron microscope imaging system of claim 12 , wherein the command component is configured to sample across multiple pixel locations as the beam or probe is in transit to a next pixel location of the subset of pixel locations.

18. An electronic microscope comprising:

an electron gun that emits an electron beam;

scan coils that deflect the electron beam;

a sample area comprising pixel locations;

a processor, wherein the processor drives the scan coils to deflect the electron beam onto the pixel locations; and

a computer-readable memory that comprises a plurality of components that are executed by the processor, the plurality of components comprising:

a command component configured to command an electron beam or probe to scan across a sample area and visit a subset of pixel locations of the sample area, the subset of pixel locations being randomly or pseudo-randomly designated;

a determiner component configured to determine actual pixel locations on the sample area that are visited by the electron beam or probe; and

a reconstruction component configured to process data collected by detectors from the visits of the electron beam or probe at the actual pixel locations and recover a reconstructed image from the processed data.

19. The electron microscope of claim 18 , wherein the reconstruction component is configured to recover the reconstructed image of the sample by using a basis pursuit recovery algorithm utilizing compressibility of the acquired data for recovering the reconstructed image.

20. The electron microscope of claim 18 , wherein the command component is configured to sample across multiple pixel locations as the beam or probe is in transit to a next pixel location of the subset of pixel location.