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

Author(s):

A. Vijayakumar and Joseph Rosen

Abstract:

“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.”

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Publication: Optics Express

Issue/Year/DOI: Optics Express Vol. 25, Issue 12, pp. 13883-13896 (2017)

DOI: 10.1364/OE.25.013883

 

Spectrum and space resolved 4D imaging by coded aperture correlation holography (COACH) with diffractive objective lens

Author(s):

A. Vijayakumar and Joseph Rosen

Abstract:

“In this Letter, we present an advanced optical configuration of coded aperture correlation holography (COACH) with a diffractive objective lens. Four-dimensional imaging of objects at the three spatial dimensions and with an additional spectral dimension is demonstrated. A hologram of three-dimensional objects illuminated by different wavelengths was recorded by the interference of light diffracted from the objects with the light diffracted from the same objects, but through a random-like coded phase mask (CPM). A library of holograms denoted point spread function (PSF) holograms were prerecorded with the same CPM, and under identical conditions, using point objects along different axial locations and for the different illuminating wavelengths. The correlation of the object hologram with the PSF hologram recorded using a particular wavelength, and at a particular axial location, reconstructs only the object corresponding to the particular axial plane and to the specific wavelength. The reconstruction results are compared with regular imaging and with another well-established holographic technique called Fresnel incoherent correlation holography.”

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Publication:  Optics Letters

Issue/Year/DOI: Optics Letters Vol.42, Issue 5, pp. 947-950 (2017)
DOI: 10.1364/OL.42.000947

Methods of Single-Channel Digital Holography for Three-Dimensional Imaging

Author(s):

R. Kelner and J. Rosen

Abstract:

“Digital holography is an effective tool for imaging three-dimensional (3-D) scenes or objects. In this paper, recently developed methods of single channel digital holography are reviewed: the joint object reference digital interferometer (JORDI), Fresnel incoherent correlation holography (FINCH), and Fourier incoherent single channel holography (FISCH).”

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Publication: IEEE Transactions on Industrial Informatics

Issue/Year/DOI: IEEE Transactions on Industrial Informatics ( Volume: 12, Issue: 1, Feb. 2016 )
DOI: 10.1109/TII.2015.2475247

Fully computed holographic stereogram based algorithm for computer-generated holograms with accurate depth cues

Author(s):

Hao Zhang and Yan Zhao and Liangcai Cao and Guofan Jin

Abstract:

“We propose an algorithm based on fully computed holographic stereogram for calculating full-parallax computer-generated holograms (CGHs) with accurate depth cues. The proposed method integrates point source algorithm and holographic stereogram based algorithm to reconstruct the three-dimensional (3D) scenes. Precise accommodation cue and occlusion effect can be created, and computer graphics rendering techniques can be employed in the CGH generation to enhance the image
fidelity. Optical experiments have been performed using a spatial light modulator (SLM) and a fabricated high-resolution hologram, the results show that our proposed algorithm can perform quality reconstructions of 3D scenes with arbitrary depth information.”

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Publication: Optics Express
Issue/Year/DOI: Optics Express Volume 23, Issue 4 pp. 3901-3913 (2015)
DOI: 10.1364/oe.23.003901

Detection of Bessel beams with digital axicons

Author(s):

Abderrahmen Trichili and Thandeka Mhlanga and Yaseera Ismail and Filippus S. Roux and Melanie McLaren and Mourad Zghal and Andrew Forbes

Abstract:

“We propose a simple method for the detection of Bessel beams with arbitrary radial and azimuthal indices, and then demonstrate it in an all-digital setup with a spatial light modulator. We confirm that the fidelity of the detection method is very high, with modal cross-talk below 5%, even for high orbital angular momentum carrying fields with long propagation ranges. To illustrate the versatility of the approach we use it to observe the modal spectrum changes during the self-reconstruction process of Bessel beams after encountering an obstruction, as well as to characterize modal distortions of Bessel beams propagating through atmospheric turbulence.”

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Publication: Optics Express

Issue/Year/DOI: Optics Express, Vol. 22 , Issue 14, pp. 17553- 17560 (2014)
DOI: 10.1364/OE.22.017553

Parallel phase-shifting digital holography with adaptive function using phase-mode spatial light modulator

Author(s): Miao Lin, Kouichi Nitta, Osamu Matoba, and Yasuhiro Awatsuji

Abstract:

“Parallel phase-shifting digital holography using a phase-mode spatial light modulator (SLM) is proposed. The phase-mode SLM implements spatial distribution of phase retardation required in the parallel phase-shifting digital holography. This SLM can also compensate dynamically the phase distortion caused by optical elements such as beam splitters, lenses, and air fluctuation. Experimental demonstration using a static object is presented.”

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Publication: Applied Optics, (subscription required)

Issue/Year/DOI: Applied Optics, Vol. 51, Issue 14, pp. 2633-2637 (2012)
doi:10.1364/AO.51.002633

Determination of wavefront structure for a Hartmann Wavefront Sensor using a phase-retrieval method

Author(s): A. Polo, V. Kutchoukov, F. Bociort, S.F. Pereira, and H.P. Urbach

Abstract:

“We apply a phase retrieval algorithm to the intensity pattern of a Hartmann wavefront sensor to measure with enhanced accuracy the phase structure of a Hartmann hole array. It is shown that the rms wavefront error achieved by phase reconstruction is one order of magnitude smaller than the one obtained from a typical centroid algorithm. Experimental results are consistent with a phase measurement performed independently using a Shack-Hartmann wavefront sensor.”

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Publication: Optics Express, (free download)

Issue/Year/DOI: Optics Express, Vol. 20, Issue 7, pp. 7822-7832 (2012)
doi:10.1364/OE.20.007822

Pure two-dimensional polarization patterns for holographic recording

Author(s): Ulises Ruiz, Clementina Provenzano, Pasquale Pagliusi, and Gabriella Cipparrone

Abstract:

“Two-dimensional (2D) polarization patterns are achieved by the interference of two pairs of beams with perpendicular planes of incidence and orthogonal polarizations (i.e. linear or circular). In both cases, imposing a phase shift of π/2 between consecutive beams contains the amplitude modulation of the optical field in the superposition region and, thus, pure 2D polarization patterns are created. The recording of these interference fields in a polarization-sensitive material, namely an amorphous azopolymer, creates reconfigurable 2D periodic microstructures with peculiar diffraction properties.”

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Publication: Optics Letters, (subscription required)

Issue/Year/DOI: Optics Letters, Vol. 37, Issue 3, pp. 311-313 (2012)
doi:10.1364/OL.37.000311

Binocular adaptive optics vision analyzer with full control over the complex pupil functions

Author(s): Christina Schwarz, Pedro M. Prieto, Enrique J. Fernández, and Pablo Artal

Abstract:

“We present a binocular adaptive optics vision analyzer fully capable of controlling both amplitude and phase of the two complex pupil functions in each eye of the subject. A special feature of the instrument is its comparatively simple setup. A single reflective liquid crystal on silicon spatial light modulator working in pure phase modulation generates the phase profiles for both pupils simultaneously. In addition, another liquid crystal spatial light modulator working in transmission operates in pure intensity modulation to produce a large variety of pupil masks for each eye. Subjects perform visual tasks through any predefined variations of the complex pupil function for both eyes. As an example of the system efficiency, we recorded images of the stimuli through the system as they were projected at the subject’s retina. This instrument proves to be extremely versatile for designing and testing novel ophthalmic elements and simulating visual outcomes, as well as for further research of binocular vision.”

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Publication: Optics Letters, (subscription required)

Issue/Year/DOI: Optics Letters, Vol. 36, Issue 24, pp. 4779-4781 (2011)
doi:10.1364/OL.36.004779

Fabrication of microscale medical devices by two-photon polymerization with multiple foci via a spatial light modulator

Author(s): Shaun D. Gittard, Alexander Nguyen, Kotaro Obata, Anastasia Koroleva, Roger J. Narayan, and Boris N. Chichkov.

Abstract:

“Two-photon polymerization is an appealing technique for producing microscale devices due to its flexibility in producing structures with a wide range of geometries as well as its compatibility with materials suitable for biomedical applications. The greatest limiting factor in widespread use of two-photon polymerization is the slow fabrication times associated with line-by-line, high-resolution structuring. In this study, a recently developed technology was used to produce microstructures by two-photon polymerization with multiple foci, which significantly reduces the production time. Computer generated hologram pattern technology was used to generate multiple laser beams in controlled positions from a single laser. These multiple beams were then used to simultaneously produce multiple microstructures by two-photon polymerization. Arrays of micro-Venus structures, tissue engineering scaffolds, and microneedle arrays were produced by multifocus two-photon polymerization. To our knowledge, this work is the first demonstration of multifocus two-photon polymerization technology for production of a functional medical device. Multibeam fabrication has the potential to greatly improve the efficiency of two-photon polymerization production of microscale devices such as tissue engineering scaffolds and microneedle arrays.”

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Publication: Biomedical Optics Express, (free download)

Issue/Year/DOI: Biomedical Optics Express, Vol. 2, Issue 11, pp. 3167-3178 (2011)
doi:10.1364/BOE.2.003167