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Objectives: To demonstrate the potential application of mixed reality (MR) holographic imaging technology in subgingival scaling and root planing (SRP) for patient with advanced periodontitis., Methods: This case series comprised the analysis of 1566 sites from 261 teeth of 10 patients with advanced periodontitis. Digital CBCT scans and intraoral scans of the patients were digitally acquired preoperatively and aligned to create a three-dimensional periodontal visualization model. Through rendering, interactive holographic images were displayed using MR. The surgeon first used MR images to communicate with the patients, and then facilitated SRP under their guidance. Probing pocket depth (PPD), clinical attachment loss (CAL), Plaque index (PI), and bleeding on probing (BOP) parameters were recorded at baseline and at 8-week postoperatively. Patient-reported outcome indicator questionnaires on self-efficacy were also collected., Results: PPD, CAL, PI, and BOP significantly decreased at 8-week following MR hologram-assisted SRP (p<0.001). For sites with PPD≥4 mm, PPD and CAL declined by 2.33±1.23 mm and 0.69±1.07 mm, respectively. PI significantly decreased from 1.94±0.61 to 0.82±0.58 (p < 0.001) and BOP sites decreased significantly from 84.11% to 40.25%. After receiving MR holograms for condition communication, most patients had a better perception of the effectiveness of SRP treatment and the benefits it brings. 80% of the subjects expressed their willingness to undergo MR-assisted periodontal treatment in the future., Conclusion: These results provide preliminary support for MR hologram-assisted digital SRP. With this technology, images of the gingiva and alveolar bone can be displayed in real time, accurately and three-dimensionally. This improves SRP effectiveness, diminishes complications, and enhances patients' confidence in the treatment., Clinical Significance: MR holographic imaging-based digital SRP is a clinically feasible and promising adjunctive periodontal treatment option. It may contribute to improved non-surgical treatment efficacy in patients with severe periodontitis., Competing Interests: Declaration of competing interest The authors declare there is no conflict of interests., (Copyright © 2024. Published by Elsevier Ltd.)

A label-free, high content, time-lapse holographic imaging system was applied to studies in pharmaceutical compound development. Multiple fields of cellular images are obtained over typically several day evaluations within standard CO 2 incubators. Events are segmented to obtain population data of cellular features, which are displayed in scattergrams and histograms. Cell tracking is accomplished, accompanied by Cartesian plots of cell movement, as well as plots of cell features vs. time in novel 4-D displays of X position, Y position, time, and cell thickness. Our review of the instrument validation data includes 1) tracking of Giant HeLa cells, which may be undergoing neosis, a process of tumor stem cell generation; 2) tracking the effects of cell cycle related toxic agents on cell lines; 3) using MicroRNAs to reverse the polarization state in macrophages to induce tumor cell killing; 4) development of liposomal nanoformulations to overcome Multi-Drug Resistance (MDR) in ovarian cancer cells; and 5) development of dual sensitive micelles to specifically target matrix metalloproteinase 2 (MMP2) over-expressing cell lines. © 2017 International Society for Advancement of Cytometry., (© 2017 International Society for Advancement of Cytometry.)

Holographic imaging as one of promising image techniques reconstructs object image using the amplitude and phase information scattered from objects. Programmable metasurface composed of digitally coding unit cells can arbitrarily manipulate amplitude and phase of the scattering wave by tailoring operation states of the unit cells, and thus achieves high‐resolution imaging reconstruction. However, the conventional metasurface can only achieves a desired holographic image on an imaging plane. This paper presented a time‐space coding 2‐bit metasurface to overcome this challenge. By rapidly switching PIN diodes loaded in metasurface unit cell according to the customized time sequences, the magnitude and phase of the ±1st order harmonic fields can be fully controlled, achieving the hologram imaging at the higher order harmonics. The proof‐of‐concept measurements are given to demonstrate the versatile holographic imaging functions at the ±1st order harmonics including two different holographic images on an imaging plane, holographic imaging and beam scanning, and holographic imaging and orbital angular momentum (OAM) wave generation, which undoubtedly enriches the applications of the programmable metasurfaces in the field of the holographic imaging. [ABSTRACT FROM AUTHOR]

Objectives: The aim of the present review was to evaluate the role of holographic imaging and its visualization techniques in providing more detailed and intuitive anatomy of the surgical area and assist in the precise implementation of surgery. Materials and methods: Medline, Embase, and Cochrane Central databases were searched for literature on the application of holographic imaging in partial nephrectomy (PN), and the history, development, application in PN as well as the future direction were reviewed. Results: A total of 304 papers that met the search requirements were included and summarized. Over the past decade, holographic imaging has been increasingly used for preoperative planning and intraoperative navigation in PN. At present, the intraoperative guidance method of overlapping and tracking virtual three dimensional images on endoscopic view in an augmented reality environment is generally recognized. This method is helpful for selective clamping, the localization of endophytic tumors, and the fine resection of complex renal hilar tumors. Preoperative planning and intraoperative navigation with holographic imaging are helpful in reducing warm ischemia time, preserving more normal parenchyma, and reducing serious complications. Conclusions: Holographic image-guided surgery is a promising technology, and future directions include artificial intelligence modeling, automatic registration, and tracking. [ABSTRACT FROM AUTHOR]

Phase manipulation plays a fundamental role in electromagnetic (EM) and optics research, i.e., the wavefront shaping depends heavily on phase modulation. However, the previous phase manipulation methods are limited to phase‐angle dimensionality, and the magnitude and phase are generally deemed as two distinct characters that should be controlled separately. Herein, a phase manipulation method in which phase is modulated by magnitude is proposed that follows an EM expression of Euler's formula. A rotation phase of linearly‐polarized waves is presented. Using this method, several unique applications in this research are demonstrated. First, a Hall effect of non‐angular‐momentum waves is obtained; second, an interdigital topology model with a unique topological‐charge control strategy is presented; and finally, the method is applied to holographic imaging, of which information of the hologram is recorded as a distribution of magnitude. Furthermore, as this method is applicable to all forms of harmonic waves, it can be potentially applied to other areas of wave phenomena such as acoustics and mechanics. [ABSTRACT FROM AUTHOR]

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A floating signage which means optical images are floating in the air is one of the useful ways to attract people's attention. Since 2019, our research group proposed unidirectional observable aerial signage display using thin film layers or dye-dopedoptical prisms to avoid mirrored imaging problem which means observers end up watching wrong messages or images from back side. In this paper, the authors describe the aero signage using quasi-spatial floating image and how to generate floating images using optical illusion and to control light paths. [ABSTRACT FROM AUTHOR]

It stands to reason that someone observes mirrored imaging according to the direction of viewing if you draw something on the transparent material. The authors dislike this mirrored imaging problem, although it is not a fatal defect. In 2021, our research group proposed window signage using dye‐doped thin film layer to avoid this problem of mirrored imaging. But our 2021 model had a defect that the transparency of a glass window with half mirror layer was less than the general glass material without half mirror because of image generating mechanism. To solve this "reflect surroundings" problem, we needed to find new technology for generating color using a transparent material. This paper shows a unidirectional observable window signage using holographic imaging or holographic optical elements for unidirectional color generating by light controls, how to make structural colors using holographic recording technology and material development. [ABSTRACT FROM AUTHOR]

How to realize acoustic holography via ultradeep‐subwavelength structures is a challenging problem in the past decades, which is thought impossible due to the linear proportional relationship between the structural thickness and acoustic wavelength. In this article, the methodology of ultrathin holography by patterning holes in an acoustic insulation plate with an ultradeep‐subwavelength thickness is introduced. The transmitted sound field can be manipulated arbitrarily to form a desired shape by designing the ultrathin pattern based on the nonlocal wave interaction theory. The physical mechanism of the nonlocal behavior to achieve a sophisticated hologram is revealed due to the interaction among the sound wave components themselves. Furthermore, the experiments are designed to map out the pressure amplitude field of a "sun" pattern in air and water, respectively. The work demonstrates the advantage of nonlocal ultrathin holography in the applications of ultrathin acoustic devices and provides inspiration for the holographic wave manipulation. [ABSTRACT FROM AUTHOR]

The PERCIVAL detector is a CMOS imager designed for the soft X-ray regime at photon sources. Although still in its final development phase, it has recently seen its first user experiments: ptychography at a free-electron laser, holographic imaging at a storage ring and preliminary tests on X-ray photon correlation spectroscopy. The detector performed remarkably well in terms of spatial resolution achievable in the sample plane, owing to its small pixel size, large active area and very large dynamic range; but also in terms of its frame rate, which is significantly faster than traditional CCDs. In particular, it is the combination of these features which makes PERCIVAL an attractive option for soft X-ray science. [ABSTRACT FROM AUTHOR]

In order to enhance channel capacity in modern wireless communications, diverse multiplexing techniques, such as polarization, frequency, and spatial multiplexing, are proposed and implemented. Here, a non‐interleaved polarization‐frequency multiplexing metasurface is proposed, which can realize independent controls of orthogonal linearly polarized or circularly polarized waves in two frequency bands to achieve four independent information channels. As a proof of concept, the metasurfaces that can independently realize four different polarized holographic images in two frequency bands are designed, simulated, and measured. The results show that two orthogonally polarized holographic images are achieved in each frequency band, respectively, which can be either linear or circular polarization. Benefitting from the advantages of non‐interleaved design, the proposed metasurfaces can reach not only high information capacity but also high information density by taking full use of the metasurface apertures. [ABSTRACT FROM AUTHOR]

Objectives: To investigate the application effect of mixed reality (MR) holographic imaging technology in the clinical surgical treatment of spinal cord glioma. Methods: The clinical data of 53 patients with spinal cord glioma who underwent surgical treatment in the Neurosurgery Department of our hospital from January 2017 to May 2020 were retrospectively studied. All the patients were divided into two groups according to different assistive technologies during the surgery: the observation group and the control group, with 30 cases and 23 cases respectively. Patients in the observation group received MR holographic imaging technology intraoperatively, while those in the control group received ultrasound. The surgical conditions of the two groups: the rate of complete resection of tumor lesions and the evaluation accuracy of complete resection were compared. Patients were followed up for 12 months in the outpatient department after surgery, and the recovery of postoperative spinal physiological function was evaluated based on imaging review and MMS scale grading, and the recurrence was obtained. Results: There was no statistical significance in the basic clinical conditions between the two groups (P>0.05), and the total tumor resection rate in the experimental group was 96.67%, and that in the control group was 82.61%, showing a statistically significant difference (P<0.05). Based on enhanced MRI examination as the standard, the evaluation accuracy of intraoperative complete tumor resection in the experimental group was 93.33%, significantly higher than that in the control group (73.54%), with a statistical significance (P<0.05). The incidence of postoperative complications was 3.33% in the experimental group and 21.74% in the control group, with a statistically significant difference (P<0.05). Postoperative follow-up showed that good recovery rate of spinal cord function in the experimental group was 56.70%, and that in the control group was 41.09%, with a statistically significant difference (P<0.05). The recurrence rate was 0 in the experimental group and 4.34% in the control group at follow-up, with no statistically significant difference (P>0.05). Conclusions: With the application of MR holographic imaging technology in the surgical treatment of spinal cord glioma, critical clinical value can be realized. Specifically, the resection degree of spinal cord glioma can be displayed in real time, accurately, and three-dimensionally, the effect of surgical resection can be improved, surgical complications can be diminished, and the recovery of spinal cord function can be accelerated. [ABSTRACT FROM AUTHOR]

Cells need to rapidly and precisely react to multiple mechanical and chemical stimuli in order to ensure precise context‐dependent responses. This requires dynamic cellular signalling events that ensure homeostasis and plasticity when needed. A less well‐understood process is cellular response to elevated interstitial fluid pressure, where the cell senses and responds to changes in extracellular hydrostatic pressure. Here, using quantitative label‐free digital holographic imaging, combined with genome editing, biochemical assays and confocal imaging, we analyse the temporal cellular response to hydrostatic pressure. Upon elevated cyclic hydrostatic pressure, the cell responds by rapid, dramatic and reversible changes in cellular volume. We show that YAP and TAZ, the co‐transcriptional regulators of the Hippo signalling pathway, control cell volume and that cells without YAP and TAZ have lower plasma membrane tension. We present direct evidence that YAP/TAZ drive the cellular response to hydrostatic pressure, a process that is at least partly mediated via clathrin‐dependent endocytosis. Additionally, upon elevated oscillating hydrostatic pressure, YAP/TAZ are activated and induce TEAD‐mediated transcription and expression of cellular components involved in dynamic regulation of cell volume and extracellular matrix. This cellular response confers a feedback loop that allows the cell to robustly respond to changes in interstitial fluid pressure. Synopsis: YAP/TAZ transcriptional co‐activators are central regulators of cellular response to changes in the extracellular and intracellular mechanical environment. This study identifies oscillating hydrostatic pressure as a new regulator of cell volume via YAP/TAZ activation. YAP/TAZ regulate cell volume and plasma membrane tensionOscillating hydrostatic pressure induces rapid and reversible changes in cellular volumeYAP/TAZ activation are essential for the cellular response to hydrostatic pressureCellular response to oscillating hydrostatic pressure involves clathrin‐dependent endocytosis and the actin cytoskeleton [ABSTRACT FROM AUTHOR]

General theory of holographic inversion with linear frequency modulation (GHI-LFM) has been proposed recently, providing the framework for further advances in the holographic methods for image reconstruction with millimeter-wave linear frequency modulation (LFM) radar. Here, accelerated holographic imaging (AHI)-LFM, an AHI method for LFM radar that exploits range stacking, is proposed. The method is developed and validated for the purpose of whole-body security screening. The image quality and the computational efficiency are compared with the original GHI-LFM algorithm. It is demonstrated that the AHI-LFM algorithm improves the reconstruction speed by at least an order of magnitude while preserving the same image quality for the image sizes arising in practical whole-body security screening. [ABSTRACT FROM AUTHOR]

Holography has been fascinating people for almost 70 years (since Gabor's invention in 1947) as a true three‐dimensional (3D) imaging technology that can replicate 3D scenes in free space. Holography has also led to important developments in physics and technology as manifested by fundamental ideas proposed by renowned scientists and holographers, such as Emmeth Lieth (off‐axis holography), Yuri Denisyuk (reflection holography), Stephen Benton (rainbow holography), and Adolf Lohmann (computer‐generated holograms). Their ideas have been established as essential concepts and have advanced considerably the field of optical and digital holography during the past fifty years. The 21st century is the age of digital technology and tremendous progress in optoelectronics and micro/nanotechnology has been accomplished. This progress has opened the doors for true holographic applications in important areas such as holographic 3D displays with photorealistic visualization, 3D quantitative imaging in biomedicine, optical metrology using digital holographic interferometry, microscopy, and tomography. Successful applications and true holographic products in the market have advanced holography to a level at which standards setting organizations must be involved to guarantee interoperability between devices and applications.

Digital coding metasurface, which provides a new approach to link the physical world and information science, has been quickly developed in recent years. However, all previously reported metasurfaces cannot achieve independent controls of different polarizations in both transmission and reflection spaces at the same time. In this work, a reconfigurable anisotropic digital coding metasurface loaded with electronically controlled PIN diodes is proposed that can independently manipulate not only the near/far‐field pattern but also the transmission and reflection modes of the electromagnetic waves under different polarizations. As a validation example, a multifunctional holographic imaging metasurface is designed, fabricated, and measured. Both simulated and measured results show that orthogonally polarized waves (vertical and horizontal polarizations) can be manipulated to achieve different images, and the transmission and reflection modes of the differently‐polarized images can be independently controlled in real time by changing the state of the loaded PIN diodes. [ABSTRACT FROM AUTHOR]

Introducing compressed sensing theory into the millimeter-wave near-field holographic imaging algorithm, it can break the Nyquist sampling limit, reconstruct the compressed echo signal, and invert the target image. In the reconstruction process, there are defects such as missing target key information, excessive invalid search volume and so on. Aiming at this problem, an adaptive multi-extreme particle swarm optimization (AMPSO) algorithm is proposed. Its advantages are that it can retain more target information, search for more extreme values, and improve the convergence speed. At the same time, the search probability in the strong scattering area is also increased, the search time is avoided in the noise area, and the number of extreme points is adjusted on a global scale. The effectiveness of the algorithm is verified by simulation and actual measurement of multiple types of targets under different experimental conditions. [ABSTRACT FROM AUTHOR]

A self-designed all-solid-state electronic 3-D millimeter-wave imaging radar is demonstrated and applied in holographic imaging for nondestructive testing of polymer materials. Full heterodyne detection is implemented in the system, which is based on a sawtooth linear frequency-modulated continuous wave, with a center frequency of 195 GHz, a bandwidth of 42 GHz, and an average power of 0.5 mW. A suitable calibration method is employed to solve the problem caused by the nonlinearity of frequency modulation. Performance parameters are established experimentally, including range resolution (3.2 mm, better than theoretical value) and lateral resolution, ranging from 1.45 to 4 mm at imaging distances from 10 to 70 mm. Simulation and experimental studies ascertain the effectiveness of the system in examining internal defects in combination with imaging algorithms, a classical range migration algorithm for surface reflection based on free-space Green’s function, and a modified subsurface imaging algorithm based on a rigorous half-space Green’s function. For surface defects and defects inside the material whose refractive index is close to air, the performances of both are similar. However, in imaging interior defects buried in a medium with substantially different refractive indices, the modified algorithm is superior, as illustrated by testing of Teflon blocks containing internal voids. Furthermore, convincing experimental evidence shows that the system can image slightly bent and tilted samples. [ABSTRACT FROM AUTHOR]

The ability of metasurfaces to simultaneously manipulate both the spin and phase of circularly polarized (CP) incident waves has attracted considerable attention from researchers. Here, we propose a reconfigurable double circular split rings (DCSRs) chiral metasurface. By introducing graphene and changing the Fermi level of graphene, dynamic circular dichroism (CD) can be achieved. The calculation results show that when the Fermi level of graphene is increased from 0.1 eV to 1 eV, the CD decreases from 0.72 to 0.09 at 0.839 THz, which provides a CD-tunable spin-controlled method. In addition, based on the graphene-enabled DCSRs, we design two metasurface arrays combining Pancharatnam-Berry (PB) phase and coding metasurface theory to realize terahertz CP wave switchable focusing and spin-controlled multi-pencil beam generation. Furthermore, we demonstrate the application of reflective holography for multiplexing circularly polarized waves. The results of this paper are expected to play a significant role in the future terahertz wireless communication system, multi-spectral imaging, and information encryption fields. • Tunable chiral metasurface achieving spin-selective absorption of EM waves. • Switchable circularly polarized wave focusing with "On" and "Off" states. • Spin-controlled multiple pencil beams generation. • Dual-channel multiplexed circularly polarized wave holographic imaging. [ABSTRACT FROM AUTHOR]

Abstract Holography is considered to be the ultimate display technology since it can account for all human visual cues such as stereopsis and eye focusing. Aside from hardware constraints for building holographic displays, there are still many research challenges regarding holographic signal processing that need to be tackled. In this overview, we delineate the steps needed to realize an end-to-end chain from digital content acquisition to display, involving the efficient generation, representation, coding and quality assessment of digital holograms. We discuss the current state-of-the-art and what hurdles remain to be taken to pave the way towards realistic visualization of dynamic holographic content. [ABSTRACT FROM AUTHOR]

Circular dichroism (CD) has gained significant recognition in the field of artificial materials. However, there is still a need for a flexible approach to modulate CD, which would enable spin-selective multidimensional manipulation of terahertz (THz) waves. In recent years, reconfigurable metasurfaces have emerged as a prominent area of research in the field of micro/nanophotonic. This study proposes a novel reconfigurable chiral metasurface utilizing the phase transition properties of vanadium dioxide (VO 2), capable of modulating CD. This metasurface not only realizes the modulation of the Pancharatnam-Berry (PB) phase in two states of VO 2 but also enables the modulation of CD at the dual THz band. Based on the principle of the PB phase to control the phase of the meta-atom, the 3-bit coded metasurface arrays were proposed to achieve high-quality THz holographic imaging. Furthermore, the near-field imaging effect is realized by utilizing the differentiation property of the absorption intensity of chiral CD meta-atom. This multifunctional device, with its simple structure, exhibits tremendous potential for applications in THz holographic imaging, THz circular polarized wave detection, and image encryption. • In this work, a reconfigurable chiral metasurface with dual THz bands CD effect is proposed. • By switching the state of VO 2 , the bandwidth of the CD effect can be expanded, and the CD effect of the dual bands can be regulated. • A 3-bit coded metasurface array utilizing the PB phase is proposed in both states of VO 2 to enable high-quality holographic imaging of the characters "V" "O" and "2". • Leveraging the chiral mechanism of the metasurface, the near-field imaging of the characters "C" "U" "M" and "T" is achieved by utilizing the amplitude difference of absorption at the two THz bands. [ABSTRACT FROM AUTHOR]

We discuss and compare three methods to generate holograms for optical tweezers: simple rounding, Floyd-Steinberg error diffusion dithering and mixed-region amplitude freedom (MRAF). These schemes are optimized for producing large arrays of tightly focused luminous spots. The algorithms are compared in terms of their speed, efficiency and accuracy, for periodic arrangements of traps; an arrangement of particular interest for the trapping and manipulation of single laser-cooled atoms in the field of quantum computing. We simulate the image formation using each of a binary amplitude modulating digital mirror device (DMD) and a phase modulating spatial light modulator (PSLM) as the display element. While a DMD allows for fast frame rates, the slower PSLM is more efficient and provides higher accuracy with a quasi-continuous variation of phase. We discuss the relative merits of each algorithm for use with both a DMD and a PSLM, allowing one to choose the ideal approach depending on the circumstances. [ABSTRACT FROM AUTHOR]

Light-field imaging and holographic imaging are currently the two mostly investigated 3-D imaging technologies because of their potentials to create the viewing environment conforming to a natural viewing condition. The basic optical geometries for image display in these imaging are not different from that of integral photography. The images in the two type of imaging are a set of different view images. These images are arranged as a 2-D point image array, and each point image is expanded with a certain angle to form a viewing zone. The differences between the two types of imaging are the number of point images in the array and the physical entities forming the images. Holographic imaging has many more point images than light-field imaging, and each image in the array consists of coherent right rays from different positions of an object. In light-field imaging, an array of pixels represents a direction view of the object. Despite these differences, they share the same goal of providing a continuous parallax to viewers and require display panels of almost the same characteristics. It is expected that in the future these two imaging techniques will be integrated into the same flat panel along with the plane image. [ABSTRACT FROM AUTHOR]

Electromagnetic holographic data are characterized by two modes, suggesting that image reconstruction requires a dual-mode sensitivity field as well. We analyze an electromagnetic holographic field based on tomography theory and Radon inverse transform to derive the expression of the electromagnetic holographic sensitivity field (EMHSF). Then, we apply the EMHSF calculated by using finite-element methods to flow simulations and holographic imaging. The results suggest that the EMHSF based on the partial derivative of radius of the complex electric potential φ is closely linked to the Radon inverse transform and encompasses the sensitivities of the amplitude and phase data. The flow images obtained with inversion using EMHSF better agree with the actual flow patterns. The EMHSF overcomes the limitations of traditional single-mode sensitivity fields. [ABSTRACT FROM AUTHOR]

The proposed ultra-thin holography manipulates the propagation behavior of acoustic waves only through the interaction between acoustic waves themselves rather than between acoustic waves and material structures. Ultrathin Acoustic Holography (Adv. Keywords: acoustic metasurfaces; holographic imaging; nonlocal coupling; ultrathin EN acoustic metasurfaces holographic imaging nonlocal coupling ultrathin 1 1 1 03/17/23 20230315 NES 230315 B Ultra-Thin Acoustic Holography b In article number 2300034, Xin Li, Xin-Ye Zou, Xue-Feng Zhu, and colleagues present a powerful methodology of ultra-thin acoustic holography theoretically and experimentally, which is applicable in diverse media including air and water. [Extracted from the article]

This paper presents a holographic projection display in which a phase-only spatial light modulator (SLM) performs three functions: beam shaping, image display, and speckle reduction. The functions of beam shaping and image display are performed by dividing the SLM window into four sub-windows loaded with different diffractive phase elements (DPEs). The DPEs are calculated using a modified iterative Fourier transform algorithm (IFTA). The function of speckle reduction is performed using temporal integration of display images containing speckles. The speckle contrast ratio of the display image is 0.39 due to the integration of eight speckled images. The system can be extended to display full-color images also by using temporal addition of elementary color images. Because the system configuration needs only an SLM, a Fourier transform lens, and two mirrors, the system volume is very small, becoming a potential candidate for micro projectors. [ABSTRACT FROM AUTHOR]

We study the quantum holographic imaging of one-dimensional electromagnetically induced grating created by a strong standing wave in an atomic medium. Entangled photon pairs, generated in a spontaneous parametric down-conversion process, are employed as the imaging light to realize coincidence recording. By theoretical analysis and numerical simulation, we find that both the amplitude and phase information of the object can be imaged with the characteristic of imaging nonlocally and of arbitrarily controllable image variation in size. [ABSTRACT FROM AUTHOR]

In this paper, an exact reconstruction formula is presented for near-field three-dimensional (3D) planar millimeter-wave (MMW) holographic imaging. The proposed formula is derived based on scalar diffraction theory, and the round-trip imaging process is equivalent to a unidirectional optical field propagation. Because of compensating the propagation loss of the source for the near-field imaging configuration, the inconsistency in range domain of the reconstructed 3D images is avoided. The proposed reconstruction formula also gives a phase correction for the reconstructed complex-valued reflectivity of the target and the range coordinate can be exactly determined. Simulations and laboratory imaging experiments are performed to demonstrate the effectiveness of the proposed reconstruction formula. [ABSTRACT FROM AUTHOR]

In this paper, we propose a simple method for realizing color holographic imaging using one thin diffractive optical element (DOE), which can reconstruct a two-dimensional color image with one phase plate at a user defined distance from phase plate. The phase plate is optimized by combining Gerchberg–Saxton algorithm and compensation algorithm for improving the resolution ratio of reproduced color images. For accelerating the computational time, the Graphic Processing Unit (GPU) is used for saving time costs. In the end, the simulation experiments verified our method. [ABSTRACT FROM AUTHOR]

Evolving from time stretching technique based on ultrashort optical pulse, wavelength-to-space-mapping imaging has become a common strategy for single-shot ultrafast imaging. In the technique, chirped broadband child pulses are generated and used to probe the transient scene typically, and the frames with temporal resolution up to picosecond scale can be achieved. Here we propose a single-shot ultrafast holographic microscopic system through a wide-spectrum pulse. A digital micromirror device (DMD)-based quasi-4 f system and a dispersive medium are involved to generate chirped multi-wavelengths child pulses in sequence. A series of off-axis holograms are spatially dispersed and separated by a grating and captured simultaneously. The time-resolved three-dimensional (3D) profiles are retrieved using the reconstruction algorithm. In the paper, the temporal evolution of optical pulse and the mechanism of holographic imaging are detailed and numerically analyzed. A 10-frames holographic microscopic system with field of view (FOV) of 0.2 mm × 0.2 mm, frame rate of 6.8 × 1010 fps and exposure time of 5.4 ps is realized, where the interval and linewidth of the multi-wavelengths are 10 nm and 0.25 nm, respectively. [ABSTRACT FROM AUTHOR]

Although holography is topic that goes back to the 1950s, the research in this field continues to be very active worldwide. A continuous growth is confirmed by the publication of more than 2000 papers each year in archival journal on different holographic issues. Here we describe shortly what appeared to us to be the most significant achievements reached in 2013 on holographic imaging. [ABSTRACT FROM PUBLISHER]