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Imaging around corners in the mid-infrared using speckle correlations
Optics Express
|May 15, 2020
Summary
Speckle correlation imaging can now visualize thermal objects around corners and through diffusers. This technique achieves near-diffraction-limited resolution, matching conventional imaging methods.
Area of Science:
- Optics and photonics
- Non-line-of-sight imaging
Background:
- Speckle correlation imaging enables visualization through scattering media and around obstacles.
- Imaging thermal, self-illuminating objects in non-line-of-sight (NLOS) conditions is a significant challenge.
Purpose of the Study:
- To demonstrate speckle correlation imaging for mid-infrared thermal objects in NLOS scenarios.
- To achieve high-resolution imaging through diffusers and around corners.
Main Methods:
- Utilized bispectrum analysis and phase retrieval algorithms.
- Applied speckle correlation techniques to mid-infrared thermal radiation.
Main Results:
- Successfully imaged mid-infrared objects through diffusers and around corners.
- Achieved resolutions approaching the diffraction limit.
- Image quality comparable to conventional line-of-sight imaging.
Conclusions:
- Bispectrum and phase retrieval methods enhance speckle correlation imaging for NLOS thermal object detection.
- This technique offers a viable solution for imaging in obscured environments.
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