Multi-layered full-field phase imaging using continuous-wave terahertz ptychography

Area of Science:

• Optics and Photonics
• Materials Science
• Imaging Technology

Background:

• Terahertz (THz) waves offer unique properties for imaging dielectric materials.
• THz phase imaging is crucial for analyzing absorption and phase modulation in thin and stacked samples.
• Existing methods face challenges with crosstalk in multi-layered imaging.

Purpose of the Study:

• To apply a 3D ptychographic iterative engine algorithm for continuous-wave THz full-field multi-layered phase imaging.
• To reconstruct the complex-valued transmission function of multi-layered samples and the probe function.
• To overcome crosstalk issues between different layers in THz imaging.

Main Methods:

• Utilized a three-dimensional ptychographic iterative engine algorithm.
• Applied continuous-wave terahertz (THz) full-field imaging.
• Reconstructed complex-valued transmission functions for a two-layered polypropylene sample.

Main Results:

• Successfully reconstructed the transmission function of each layer in a two-layered sample, eliminating crosstalk.
• Observed field-of-view enlargement at the second object layer.
• Demonstrated a lensless, compact imaging approach.

Conclusions:

• The 3D ptychographic iterative engine algorithm enables effective multi-layered THz phase imaging.
• The method provides layer-specific reconstructions immune to crosstalk.
• This lensless technique shows potential for advanced 3D terahertz imaging applications.