Image formation by inversion of scattered field data: experiments and computational simulation.

Area of Science:

• Microscopy and Imaging
• Computational Physics
• Optical Scattering

Background:

• Reconstructing the 3-D scattering potential of microscopic objects is crucial for understanding their properties.
• Amplitude and phase data of scattered fields offer a pathway to object reconstruction.
• Challenges exist in experimental data acquisition and computational processing for accurate reconstruction.

Purpose of the Study:

• To reconstruct the 3-D scattering potential and 2-D equivalent object from scattered field data.
• To compare experimental results with computational simulations based on Mie diffraction theory.
• To analyze the impact of experimental limitations on the reconstruction process and computational efficiency.

Main Methods:

• Computational simulation using Mie diffraction theory for coated spheres.
• Experimental measurement of scattered fields from a 40-microm diameter sphere using interferometric methods.
• Development and application of two methods for recording scattered field data, assessing phase quantization sensitivity.

Main Results:

• Successful reconstruction of the 3-D scattering potential and 2-D equivalent object.
• Experimental results are discussed in conjunction with computer simulations.
• Experimental data limitations (restricted range) result in a smeared Point Spread Function (PSF), but this also reduces computation time for digital inversion.

Conclusions:

• The study demonstrates the feasibility of reconstructing microscopic object scattering potentials from scattered field data.
• Experimental constraints, while causing image degradation (PSF smear), offer a computational advantage.
• The findings provide insights into optimizing 3-D object reconstruction techniques in microscopy and optics.