Optical imaging with phase-coded aperture

Chi, Wanli; George, Nicholas

doi:10.1364/oe.19.004294

Cited by 52 publications

(21 citation statements)

References 4 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Incoherent 2D lensless cameras have been demonstrated using amplitude masks [1], diffractive masks [2,3], random reflective surfaces [4,5], and modified microlens arrays [6] as the encoding element. 2D lensless imaging with coherent illumination has been demonstrated in [7,8], and extended to 3D [9][10][11][12], but these methods require active or coherent illumination. Our system uses a similar lensless architecture but extends both the design and image reconstruction to enable 3D capture without the need for coherent lighting.…”

Section: Introductionmentioning

confidence: 99%

DiffuserCam: lensless single-exposure 3D imaging

Antipa

Kuo

Heckel

et al. 2017

Optica

499

340

View full text Add to dashboard Cite

We demonstrate a compact and easy-to-build computational camera for single-shot 3D imaging. Our lensless system consists solely of a diffuser placed in front of a standard image sensor. Every point within the volumetric field-of-view projects a unique pseudorandom pattern of caustics on the sensor. By using a physical approximation and simple calibration scheme, we solve the large-scale inverse problem in a computationally efficient way. The caustic patterns enable compressed sensing, which exploits sparsity in the sample to solve for more 3D voxels than pixels on the 2D sensor. Our 3D voxel grid is chosen to match the experimentally measured two-point optical resolution across the field-of-view, resulting in 100 million voxels being reconstructed from a single 1.3 megapixel image. However, the effective resolution varies significantly with scene content. Because this effect is common to a wide range of computational cameras, we provide new theory for analyzing resolution in such systems.

show abstract

Section: Introductionmentioning

confidence: 99%

DiffuserCam: lensless single-exposure 3D imaging

Antipa

Kuo

Heckel

et al. 2017

Optica

499

340

View full text Add to dashboard Cite

show abstract

“…Imaging with a phase coded aperture has already been proposed by Chi and George [22]. However, Chi and George avoided from recording a digital hologram of a 3D scene and their results have suffered from high level of background noise because of lack of any noise reduction mechanism.…”

Section: Introductionmentioning

confidence: 99%

Interferenceless coded aperture correlation holography–a new technique for recording incoherent digital holograms without two-wave interference

2017

View full text Add to dashboard Cite

Recording digital holograms without wave interference simplifies the optical systems, increases their power efficiency and avoids complicated aligning procedures. We propose and demonstrate a new technique of digital hologram acquisition without two-wave interference. Incoherent light emitted from an object propagates through a random-like coded phase mask and recorded directly without interference by a digital camera. In the training stage of the system, a point spread hologram (PSH) is first recorded by modulating the light diffracted from a point object by the coded phase masks. At least two different masks should be used to record two different intensity distributions at all possible axial locations. The various recorded patterns at every axial location are superposed in the computer to obtain a complex valued PSH library cataloged to its axial location. Following the training stage, an object is placed within the axial boundaries of the PSH library and the light diffracted from the object is once again modulated by the same phase masks. The intensity patterns are recorded and superposed exactly as the PSH to yield a complex hologram of the object. The object information at any particular plane is reconstructed by a cross-correlation between the complex valued hologram and the appropriate element of the PSH library. The characteristics and the performance of the proposed system were compared with an equivalent regular imaging system.

show abstract

“…The relaxation of the interference condition improves the SNR during reconstruction and the power efficiency of the imaging process is increased. At this point, it should be mentioned that imaging with a phase-coded aperture has already been proposed by Chi and George [55]. However, Ref.…”

Section: Interferenceless Coded Aperture Correlation Holographymentioning

confidence: 97%

Review of 3D Imaging by Coded Aperture Correlation Holography (COACH)

et al. 2019

View full text Add to dashboard Cite

Coded aperture correlation holography (COACH) is a relatively new technique to record holograms of incoherently illuminated scenes. In this review, we survey the main milestones in the COACH topic from two main points of view. First, we review the prime architectures of optical hologram recorders in the family of COACH systems. Second, we discuss some of the key applications of these recorders in the field of imaging in general, and for 3D super-resolution imaging, partial aperture imaging, and seeing through scattering medium, in particular. We summarize this overview with a general perspective on this research topic and its prospective directions.

show abstract

Optical imaging with phase-coded aperture

Cited by 52 publications

References 4 publications

DiffuserCam: lensless single-exposure 3D imaging

DiffuserCam: lensless single-exposure 3D imaging

Interferenceless coded aperture correlation holography–a new technique for recording incoherent digital holograms without two-wave interference

Review of 3D Imaging by Coded Aperture Correlation Holography (COACH)

Contact Info

Product

Resources

About