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Speckle patterns have been used widely in imaging techniques such as ghost imaging, dynamic speckle illumination microscopy, structured illumination microscopy, and photoacoustic fluctuation imaging. Recent advances in the ability to control the statistical properties of speckles has enabled the customization of speckle patterns for specific imaging applications. In this work, we design and create special speckle patterns for parallelized nonlinear pattern-illumination microscopy based on fluorescence photoswitching. We present a proof-of-principle experimental demonstration where we obtain a spatial resolution three times higher than the diffraction limit of the illumination optics in our setup. Furthermore, we show that tailored speckles vastly outperform standard speckles. Our work establishes that customized speckles are a potent tool in parallelized super-resolution microscopy.
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This content will become publicly available on January 1, 2026
Supergrowth in speckle patterns
Supergrowth occurs when the local amplitude growth rate of a wave is greater than that predicted by the band limit. While generating supergrowth on demand requires precise source modulation, we demonstrate that supergrowth occurs naturally in a sum of random plane waves. We measure the supergrowing fractional area of transverse, monochromatic, fully developed speckle patterns. For speckle with a disk spectrum, we find that the average fractional supergrowing area approaches 20%. We compare the supergrowing and superoscillating fractional areas and find great similarity in behavior. Our results inform on the ubiquity of superphenomena in speckle patterns and are relevant to imaging and estimation.
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- Award ID(s):
- 2244031
- PAR ID:
- 10579861
- Publisher / Repository:
- Optica
- Date Published:
- Journal Name:
- Optics Letters
- Volume:
- 50
- Issue:
- 1
- ISSN:
- 0146-9592
- Page Range / eLocation ID:
- 137
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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