5 papers
Structured Illumination Scanning Thermography (SISTER)
Pengfei Zhu, Julien Lecompagnon, Philipp Daniel Hirsch +1
Conventional non-invasive photothermal imaging techniques are fundamentally constrained by the diffusive nature of heat transport, which causes severe energy dissipation during sub…
Generalized Virtual-Wave Theory for Photothermal Coherence Tomography under Arbitrary Excitation Toward Non-Contact Industrial Inspection of Composite Materials
Pengfei Zhu, Julien Lecompagnon, Philipp Daniel Hirsch +1
Photothermal imaging is a powerful noncontact and nondestructive technique for subsurface inspection of composite materials, yet its performance is fundamentally limited by the dif…
A Unified Framework for Virtual Wave Transform: From Generalized Formulation to Excitation-Specific Projection
Pengfei Zhu, Julien Lecompagnon, Philipp Daniel Hirsch +1
We present a unified theoretical framework for the mapping between diffusive and wave-like dynamics, formulated as a spectral integral operator acting on temporal fields. By introd…
The Spectral Domain Snell Law in Diffusion-Wave Fields
Pengfei Zhu, Julien Lecompagnon, Philipp Daniel Hirsch +2
Snell law is traditionally regarded as a hallmark of phase-propagating phenomena such as optical, acoustic, elastic, electromagnetic, and quantum waves. In contrast, purely diffusi…
Generalized virtual wave reconstruction for vibrothermography: Overcoming the wavefront-free behavior and quantification challenges in the diffusion-wave field
Pengfei Zhu, Julien Lecompagnon, Mathias Ziegler +2
Wavefront-free behavior and the resulting quantification difficulties are intrinsic limitations of vibrothermography due to the diffusive nature of thermal fields. This work propos…