Inverse Reconstruction of Double Imaging Schlieren
Abstract
Double imaging is a common artefact in off-axis single-mirror Schlieren systems. Depending on the distance between the object of interest and the mirror, together with the off-axis imaging geometry, such systems often capture images containing a superposition of the target image and a displaced ghost image, resulting in the so-called double imaging phenomenon. This not only degrades image quality, but also complicates its interpretation. To address this problem, we present a new model for ghost image displacement that takes into consideration finite-aperture support, defocus, and magnification. We then use this model to reconstruct the target image via total variation regularisation with a matrix-free alternating direction method of multipliers (ADMM) algorithm. Extensive experiments using both synthetic and real Schlieren images validate the proposed model, show the effectiveness and efficiency of our algorithm, and evaluate its performance under parameter mismatch. The proposed framework provides a computational alternative to hardware-based suppression of double imaging, enabling physics-consistent reconstruction while preserving the simplicity and compactness of off-axis single-mirror Schlieren systems.
Related
- Bidirectional schlieren imaging using dual-LED illumination and a lens aperture as a knife-edge
- Quantitative schlieren imaging of a laser-ionized plasma channel in atomic vapor using symbolic regression
- Long-Wave Infrared Wavefront Sensing based on Background-oriented Schlieren
- Inverse reconstruction of dissipative Kerr soliton interactions
- Radiative double inverse seesaw and dark matter in an alternative gauged U(1)B−L model
BibTeX
@misc{saxena2026inverse,
title = {{Inverse Reconstruction of Double Imaging Schlieren}},
author = {Shubham Saxena and João F. C. Mota},
howpublished = {arXiv},
year = {2026},
month = oct,
doi = {10.48550/arxiv.2610.33214},
eprint = {2610.33214},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2610.33214},
}
RIS
TY - UNPB
TI - Inverse Reconstruction of Double Imaging Schlieren
AU - Shubham Saxena
AU - João F. C. Mota
PY - 2026
DA - 2026/10/23
PB - arXiv
DO - 10.48550/arxiv.2610.33214
UR - https://arxiv.org/abs/2610.33214
AB - Double imaging is a common artefact in off-axis single-mirror Schlieren systems. Depending on the distance between the object of interest and the mirror, together with the off-axis imaging geometry, such systems often capture images containing a superposition of the target image and a displaced ghost image, resulting in the so-called double imaging phenomenon. This not only degrades image quality, but also complicates its interpretation. To address this problem, we present a new model for ghost image displacement that takes into consideration finite-aperture support, defocus, and magnification. We then use this model to reconstruct the target image via total variation regularisation with a matrix-free alternating direction method of multipliers (ADMM) algorithm. Extensive experiments using both synthetic and real Schlieren images validate the proposed model, show the effectiveness and efficiency of our algorithm, and evaluate its performance under parameter mismatch. The proposed framework provides a computational alternative to hardware-based suppression of double imaging, enabling physics-consistent reconstruction while preserving the simplicity and compactness of off-axis single-mirror Schlieren systems.
ER -