Sökning: "phase retrieval"

Visar resultat 1 - 5 av 47 avhandlingar innehållade orden phase retrieval.

  1. 1. Phase Retrieval Methods for Electromagnetic Source Modeling

    Författare :Markus Johansson; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; source modeling; optimization; SAR; phase retrieval; dosimetry;

    Sammanfattning : Modeling of the field distributions from electromagnetic sources is of interest for various applications including electromagnetic compatibility investigations, near-field to far-field transformations, antenna diagnostics and electromagnetic dosimetry. In order to determine whether exposure safety guidelines, such as the EU directive 2004/40/EC, are complied with, source modeling methods are important. LÄS MER

  3. 2. High-resolution biomedical phase-contrast tomography

    Författare :William Twengström; Hans Hertz; Anna Burvall; Marco Stampanoni; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; x-ray; x-ray imaging; biomedical; phase contrast; tomography; zebrafish; coronary artery; virtual histology; ring artifacts; phase retrieval; mummy; Fysik; Physics;

    Sammanfattning : Improved three-dimensional biomedical imaging can give a better understanding of tissue structure, growth and diseases. Most present imaging techniques that provide cellular spatial resolution are based on visible or infrared light. These methods cannot image deeper than a millimeter into tissue. LÄS MER

  4. 3. Optical Memories and Processing in Time- and Frequency Domain

    Författare :Baozhu Luo; Atomfysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Optical storage; photon echo; spectral hole burning; nonlinear optics; fiber amplifier; logical operation; phase retrieval; polarization holographic recording and retrieval; optical processing; Atomic and molecular physics; Atom- och molekylärfysik; Fysicumarkivet A:1998:Luo;

    Sammanfattning : Spectral hole burning and photon echoes are the techniques for frequency-selective optical memories, which have the potential to increase areal data storage density by a factor 10**7. They also have the capability to perform in-memory data processing. LÄS MER

  5. 4. Numerical and experimental aspect of coherent lensless imaging

    Författare :Erik Malm; NanoLund: Centre for Nanoscience; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Coherent diffractive imaging; Holography; Phase retrieval; Diffraction; Inverse scattering; XUV light; non-rigid image registration; Fysicumarkivet A:2021:Malm;

    Sammanfattning : This thesis is devoted to the understanding, application, and extension of coherent lensless imaging methods for microscopy purposes. Particular attention is given to the Fourier transform holography and coherent diffractive imaging methods. LÄS MER

  7. 5. Complex source modeling for electromagnetic dosimetry

    Författare :Markus Johansson; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; optimization; phase-retrieval; source modeling; dosimetry; SAR;

    Sammanfattning : Electromagnetic modeling of complex sources is useful in dosimetry applications as well as for near-field to far-field transformations and antennadiagnostics. In order to determine whether exposure safety guidelines, such as the EU directive 2004/40/EC, are complied with, it is important to be able tomodel the field distribution from electromagnetic sources. LÄS MER