Non-invasive super-resolution imaging through dynamic scattering media (original) (raw)

Non-invasive super-resolution imaging through scattering media using fluctuating speckles

2021

Extending super-resolution imaging techniques to objects hidden in strongly scattering media potentially revolutionize the technical analysis for much broader categories of samples, such as biological tissues. The main challenge is the media’s inhomogeneous structures which scramble the light path and create noise-like speckle patterns, hindering the object’s visualization even at a low-resolution level. Here, we propose a computational method relying on the object’s spatial and temporal fluctuation to visualize nanoscale objects through scattering media non-invasively. The fluctuating object can be achieved by random speckle illumination, illuminating through dynamic scattering media, or flickering emitters. The optical memory effect allows us to derive the object at diffraction limit resolution and estimate the point spreading function (PSF). Multiple images of the fluctuating object are obtained by deconvolution, then super-resolution images are achieved by computing the high ord...

Imaging moving targets through scattering media

Optics Express, 2017

Optical microscopy in complex, inhomogeneous media is challenging due to the presence of multiply scattered light that limits the depths at which diffraction-limited resolution can be achieved. One way to circumvent the degradation in resolution is to use speckle-correlationbased imaging (SCI) techniques, which permit imaging of objects inside scattering media at diffraction-limited resolution. However, SCI methods are currently limited to imaging sparsely tagged objects in a dark-field scenario. In this work, we demonstrate the ability to image hidden, moving objects in a bright-field scenario. By using a deterministic phase modulator to generate a spatially incoherent light source, the background contribution can be kept constant between acquisitions and subtracted out. In this way, the signal arising from the object can be isolated, and the object can be reconstructed with high fidelity. With the ability to effectively isolate the object signal, our work is not limited to imaging bright objects in the dark-field case, but also works in bright-field scenarios, with non-emitting objects.

Deep speckle correlation: a deep learning approach toward scalable imaging through scattering media

Optica

Imaging through scattering is an important, yet challenging problem. Tremendous progress has been made by exploiting the deterministic input-output 'transmission matrix' for a fixed medium. However, this 'one-to-one' mapping is highly susceptible to speckle decorrelations-small perturbations to the scattering medium lead to model errors and severe degradation of the imaging performance. Our goal here is to develop a new framework that is highly scalable to both medium perturbations and measurement requirement. To do so, we propose a statistical 'one-to-all' deep learning technique that encapsulates a wide range of statistical variations for the model to be resilient to speckle decorrelations. Specifically, we develop a convolutional neural network (CNN) that is able to learn the statistical information contained in the speckle intensity patterns captured on a set of diffusers having the same macroscopic parameter. We then show for the first time, to the best of our knowledge, that the trained CNN is able to generalize and make high-quality object predictions through an entirely different set of diffusers of the same class. Our work paves the way to a highly scalable deep learning approach for imaging through scattering media. diffuser camera Diffusers for training Unseen diffusers for testing object. .. .. .

Large field of view imaging through scattering media with spatial information demultiplexing

2017

Optically focusing and imaging through scattering media are challenging tasks but have widespread applications from scientific research to biomedical applications and daily life. Benefiting from the memory effect (ME) for speckle intensity correlations, only one single-shot speckle pattern can be used for the high quality recovery of the objects and avoid some complicated procedures to reduce scattering effects. However, this ME behavior gives a strict limitation to the field of view (FOV) for imaging through scattering media. Objects beyond the ME region cannot be recovered and only produces unwanted speckle patterns, causing reduction in the speckle contrast and recovery quality. Here, we extract the spatial information from these unavoidable speckle pattern produced by the object extended beyond the ME region, and enlarge the FOV of the system. All information from a large object is scrambled and mixed into one single speckle image. Regional point spreading functions (PSFs), whic...

Sub-Rayleigh Imaging via Speckle Illumination

qopt.postech.ac.kr

We demonstrate sub-Rayleigh limit imaging of an object via speckle illumination. Imaging beyond the conventional Rayleigh limit is achieved by illuminating the object with pseudo-thermal light which exhibits a random speckle pattern. An object image is reconstructed from the second-order correlation measurement and the resolution of the image, which exceeds the Rayleigh limit, is shown to be related to the size of the speckle pattern that is tied to the lateral coherence length of the pseudo-thermal light.

Depth-resolved speckle-correlations imaging through scattering layers via coherence gating

Optics Letters, 2018

Recently, novel imaging techniques based on the 'memory-effect' speckle-correlations have enabled diffraction-limited imaging through scattering layers and around corners. These techniques, however, are currently limited to imaging only small planar objects that are contained within the angular and axial range of the memory effect. In addition, they do not provide depth information or depth sectioning capability. Here, we extend speckle-correlation imaging to include high-resolution depth-sectioning capability in reflection-mode, by combining it with coherence-gating via low coherence holography. We demonstrate depth measurements of hidden targets through a scattering layer, and speckle-correlation imaging using coherence-gated scattered light.

NOISE 2 imaging system:?seeing through scattering tissue with a reference point

Optics Letters, 2004

We propose a f ly-eye-like imaging system for seeing objects embedded in scattering media. Objects are recovered from many speckled images observed by a digital camera through a microlens array. Each microlens in the array generates a speckle image of the object buried between two layers of chicken breast tissue. In the computer each image is Fourier transformed jointly with an image of the speckled pointlike source captured under the same conditions. A set of the squared magnitudes of the Fourier-transformed pictures is accumulated to form a single average picture. This final picture is again Fourier transformed, resulting in the reconstruction of the hidden object.

Single-shot large field of view imaging with scattering media by spatial demultiplexing

Applied Optics

Optically focusing and imaging through strongly scattering media are challenging tasks but have widespread applications from scientific research to biomedical applications and daily life. Benefiting from the memory effect (ME) for speckle intensity correlations, only one single-shot speckle pattern can be used for the high quality recovery of the objects and avoiding some complicated procedures to reduce scattering effects. In spite of all the spatial information from a large object being embedded in a single speckle image, ME gives a strict limitation to the field of view (FOV) for imaging through scattering media. Objects beyond the ME region cannot be recovered and only produce unwanted speckle patterns, causing reduction in the speckle contrast and recovery quality. Here, we extract the spatial information by utilizing these unavoidable speckle patterns, and enlarge the FOV of the optical imaging system. Regional point spreading functions (PSFs), which are fixed and only need to be recorded once for all time use, are employed to recover corresponding spatial regions of an object by deconvolution algorithm. Then an automatic weighted averaging in an iterative process is performed to obtain the object with significantly enlarged FOV. Our results present an important step toward an advanced imaging technique with strongly scattering media.

Noninvasive optical tomographic imaging by speckle ensemble

Optical Information Systems III, 2005

We survey recently invented methods of optical tomographic imaging through scattering medium. The threedimensional structure of an object hidden between two biological tissues is recovered from many noisy speckle pictures obtained on the output of a multi-channeled optical imaging system.