Systems and methods for sub-aperture based aberration measurement and correction in interferometric imaging
AssigneeCarl Zeiss Meditec AG
InventorsAbhishek Kumar, Alexandre R. Tumlinson, Rainer Leitgeb
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Abstract
Systems and methods for sub-aperture correlation based wavefront measurement in a thick sample and correction as a post processing technique for interferometric imaging to achieve near diffraction limited resolution are described. Theory, simulation and experimental results are presented for the case of full field interference microscopy. The inventive technique can be applied to any coherent interferometric imaging technique and does not require knowledge of any system parameters. In one embodiment of the present invention, a fast and simple way to correct for defocus aberration is described. A variety of applications for the inventive method are presented.
Claims36
A method for characterizing a wavefront in collected interferometric data on a sample, wherein the interferometric data is generated using a broad bandwidth light source and wherein the data contains information about lateral structure within the sample, said method comprising:
- dividing the interferometric data into subsections at a plane where the wavefront should be characterized;
- generating images of the structure for at least two of the subsections by transforming each subsection of the data to an image plane in the sample containing the structure;
- determining a correlation between the at least two images;
- characterizing the wavefront using the correlation;
- and
- storing, displaying, or using as input to a subsequent process the resulting wavefront characterization.
An interferometric imaging device for imaging a light scattering object comprising:
- a broadband light source arranged to generate a beam of radiation;
- a beam divider for separating the beam into reference and sample arms, wherein the sample arm contains the light scattering object to be imaged, wherein the light scattering object has structure in the transverse direction to the propagation direction of the beam;
- optics to direct said beam of radiation on the light scattering object to be imaged and for combining light scattered from the object and light returning from the reference arm;
- a detector for recording the combined light, wherein said detector is located at an imaging plane of the object;
- and
- a processor for generating an aberration corrected image in response to signals generated by the detector, said processor transforming the signals generated by the detector to a plane where the aberration is to be characterized, dividing the transformed data into subsections, generating images for at least two of the subsections by transforming the subsection data to an image plane in the sample containing the structure, determining a correlation between the at least two images, and using the correlation to correct for an aberration.
A method for characterizing a wavefront in optical coherence tomography imaging data on a sample:
- collecting optical coherence tomography (OCT) imaging data of a sample, wherein said sample has structure in the transverse direction;
- transforming the data to generate image data at a particular depth in the sample where the transverse structure is visible;
- transforming the image data to a plane where the wavefront is to be characterized;
- dividing the transformed data into subsections;
- generating images of the structure for at least two of the subsections by transforming each of the subsections of the data to an image plane in the sample containing the structure;
- determining a correlation between the at least two images;
- characterizing the wavefront using the correlation;
- and
- storing, displaying, or using as input to a subsequent process the resulting wavefront characterization.
Dependencies are inferred from the claim text.