Passive ghost imaging using caustics modeling

Zhao, Ming; Uhlmann, Jeffrey; Lanzagorta, Marco; Kanugo, Jayanth; Parashar, Aditya; Jitrik, Oliverio; Venegas-Andraca, Salvador E.

doi:10.1117/12.2262656

Cited by 3 publications

(2 citation statements)

References 18 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Although these slowly varying phase masks still produce random speckle patterns in the far-field, predictable caustics are produced at a characteristic propagation distance, with the transition between the two regimes having been studied previously 11 . Using caustics for single-pixel imaging has also been postulated previously, but in that work did not yield recognisable images 12 .…”

mentioning

confidence: 85%

Single-pixel imaging using caustic patterns

Toninelli

Stellinga

Sephton

et al. 2020

Sci Rep

View full text Add to dashboard Cite

Single-pixel imaging uses a time-varying transmission mask placed in the illumination to achieve imaging without the use of detector arrays. While most research in this field uses sophisticated masks implemented using spatial light modulators, such methods are not available at all lengthscales and wavelengths of illumination. Here we show that alternatively a sequence of projected caustic intensity patterns can be used as the basis for the single-pixel imaging of objects. caustics can be formed using slowly varying random phase masks, such as for example the surface of a swimming pool, which potentially makes using caustics an option at a range of lengthscales and wavelengths.Single-pixel cameras are a form of computational imaging where a time-varying mask is used to create projected patterns to illuminate an object and a single-pixel detector used to measure the total time-varying intensity of the back-scattered light. Equivalently, the object can be illuminated full-field and the time varying mask inserted prior to the detector. In both configurations, the signals from the detector are a measure of the overlap between the mask pattern with the object and, as pioneered by Baraniuk and co-workers, given many such measurements corresponding to different patterns it is possible to reconstruct an image of the object 1,2 . One advantage of such single-pixel approaches is that they remove the need for detector arrays, which can be prohibitively expensive, or simply unavailable, at some operating wavelengths.Much of the research in the area of single-pixel cameras has been directed towards the choice/design of mask patterns and the algorithms needed to reconstruct the image from these patterns and detector data 3 . The choice of patterns ranges from patterns based upon random laser speckle 4 , to those implemented using spatial light modulators capable of creating complicated masks at very high refresh rates. These possible masks include both Hadamard 5 and more bespoke patterns aimed at optimising specific scenarios 6 . However, the use of a spatial light modulator sets a limitation upon the operating wavelengths, requiring sophisticated solutions at any wavelength much removed from the visible spectrum 7 .Rather than using designed masks, the use of laser speckle makes possible the application of a wide variety of random processes for the generation of the illumination patterns, but still leaves the problem of needing to know the precise spatial form of the patterns produced 8,9 . Measuring these patterns with a detector array or other imaging system would largely negate the operational advantage of the single-pixel approach, hence the form of the individual patterns need to be predicted from knowledge of the process producing it. This prediction might be direct from knowledge of a transmission mask imaged to the plane of the object, or from knowledge of the mask and the subsequent computational propagation of the light to the object plane. As an alternative to speckle, which can be difficult to predict, in this wor...

show abstract

mentioning

confidence: 85%

Single-pixel imaging using caustic patterns

Toninelli

Stellinga

Sephton

et al. 2020

Sci Rep

View full text Add to dashboard Cite

show abstract

“…In the experiments, the object is modulated by coded patterns, and the transmitted light of the object is collected by a bucket detector through a highly scattered media. Zhao et al proposed a passive ghost imaging scheme, which uses caustics illumination patterns to detect large objects in low‐light maritime environments. Mingnan Le et al investigated the computational ghost imaging under the underwater conditions for different turbidities and from different angles .…”

Section: Introductionmentioning

confidence: 99%

Underwater polarization‐based single pixel imaging

Zhao

et al. 2019

J Soc Info Display

Self Cite

View full text Add to dashboard Cite

This paper extends single pixel imaging (SPI) to underwater scenario. Backscattering, which is a limiting factor for underwater imaging, is analyzed for the SPI, and the forward model of SPI under backscattering is formulated. Inspired by the polarization‐based descattering technique, we propose the two cross‐polarization SPI detection scheme to eliminate the backscattering light. The descattered image is reconstructed from the cross‐polarization data. Experimentally, we construct the underwater polarization‐based single‐pixel imaging system. And we test our scheme under different turbidity water. It is shown in experiments that our method can provide a clear image at turbid water of 32FTU, where the classical SPI has been severely contaminated by the backscattering, even under the best the polarization state.

show abstract

Caustic networks with customized intensity statistics

Menz¹,

Zannotti²,

Denz

et al. 2023

Opt. Express

View full text Add to dashboard Cite

Controlling random light is a key enabling technology that pioneered statistical imaging methods like speckle microscopy. Such low-intensity illumination is especially useful for bio-medical applications where photobleaching is crucial. Since the Rayleigh intensity statistics of speckles do not always meet the requirements of applications, considerable effort has been dedicated to tailoring their intensity statistics. A special random light distribution that naturally comes with radically different intensity structures to speckles are caustic networks. Their intensity statistics support low intensities while allowing sample illumination with rare rouge-wave-like intensity spikes. However, the control over such light structures is often very limited, resulting in patterns with inadequate ratios of bright and dark areas. Here, we show how to generate light fields with desired intensity statistics based on caustic networks. We develop an algorithm to calculate initial phase fronts for light fields so that they smoothly evolve into caustic networks with the desired intensity statistics during propagation. In an experimental demonstration, we exemplarily realize various networks with a constant, linearly decreasing and mono-exponential probability density function.

show abstract

Passive ghost imaging using caustics modeling

Cited by 3 publications

References 18 publications

Single-pixel imaging using caustic patterns

Single-pixel imaging using caustic patterns

Underwater polarization‐based single pixel imaging

Caustic networks with customized intensity statistics

Contact Info

Product

Resources

About