Open AccessSelf-calibrated 3D differential phase contrast microscopy with optimized illumination
Author(s) -
Ruiming Cao,
Michael Kellman,
David Ren,
Regina Eckert,
Laura Waller
Publication year - 2022
Publication title -
biomedical optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.362
H-Index - 86
ISSN - 2156-7085
DOI - 10.1364/boe.450838
Subject(s) - focus (optics) , optics , microscope , microscopy , phase contrast imaging , refractive index , holography , computer science , depth of focus (tectonics) , artificial intelligence , digital holographic microscopy , differential interference contrast microscopy , position (finance) , computer vision , phase (matter) , materials science , phase contrast microscopy , physics , paleontology , subduction , finance , quantum mechanics , biology , economics , tectonics
3D phase imaging recovers an object's volumetric refractive index from intensity and/or holographic measurements. Partially coherent methods, such as illumination-based differential phase contrast (DPC), are particularly simple to implement in a commercial brightfield microscope. 3D DPC acquires images at multiple focus positions and with different illumination source patterns in order to reconstruct 3D refractive index. Here, we present a practical extension of the 3D DPC method that does not require a precise motion stage for scanning the focus and uses optimized illumination patterns for improved performance. The user scans the focus by hand, using the microscope's focus knob, and the algorithm self-calibrates the axial position to solve for the 3D refractive index of the sample through a computational inverse problem. We further show that the illumination patterns can be optimized by an end-to-end learning procedure. Combining these two, we demonstrate improved 3D DPC with a commercial microscope whose only hardware modification is LED array illumination.