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1

Kang, Hoonjong, Dimana Nazarova, Branimir Ivanov, Sunghee Hong, Joo Sup Park, Youngmin Kim, Jiyong Park, Nataliya Berberova, Elena Stoykova, and Nikola Malinowski. "Digital Holographic Printing Methods for 3D Visualization of Cultural Heritage Artifacts." Digital Presentation and Preservation of Cultural and Scientific Heritage 4 (September 30, 2014): 69–78. http://dx.doi.org/10.55630/dipp.2014.4.8.

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Holography enables capture and reconstruction of the optical field scattered from three-dimensional (3D) objects. The hologram encodes both amplitude and phase of the field under coherent illumination, whereas photography records only the amplitude by incoherent light. 3D visualization feature of holography motivates expansion of research efforts dedicated to digital holographic imaging methods as a holographic display or a holographic printer. The paper presents two holographic 3D printing techniques which combine digital 3D representation of an object with analog holographic recording. Generation of digital contents is considered for a holographic stereogram printer and a recently proposed wavefront printer. These imaging methods could be applied to specific artifacts which are difficult to be recorded by conventional analog holography.
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PARK, Jung-Hoon, Kyoohyun KIM, and YongKeun PARK. "Holographic Optical Imaging and Manipulation Techniques." Physics and High Technology 26, no. 3 (March 31, 2017): 7–14. http://dx.doi.org/10.3938/phit.26.008.

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Smith, D., O. Yurduseven, B. Livingstone, and V. Schejbal. "Microwave imaging using indirect holographic techniques." IEEE Antennas and Propagation Magazine 56, no. 1 (February 2014): 104–17. http://dx.doi.org/10.1109/map.2014.6821762.

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Howlett, Isela D., Wanglei Han, Michael Gordon, Photini Rice, Jennifer K. Barton, and Raymond K. Kostuk. "Volume holographic imaging endoscopic design and construction techniques." Journal of Biomedical Optics 22, no. 5 (May 31, 2017): 056010. http://dx.doi.org/10.1117/1.jbo.22.5.056010.

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5

McCartney, M. R. "Electron Holographic Imaging of Magnetic Materials at Nanometer Scale Resolution." Microscopy and Microanalysis 3, S2 (August 1997): 519–20. http://dx.doi.org/10.1017/s143192760000948x.

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Traditional electron microscopy techniques for imaging magnetic microstructure include out-of-focus Fresnel or Lorentz imaging, Foucault imaging and differential phase contrast (DPC). Off-axis electron holography provides access to both the amplitude and phase of the electron wave which has passed through the sample and therefore can provide direct, quantitative information about the in-plane component of the magnetic induction. The Philips CM200-FEG microscope which was used for the holography described here is equipped with a powerful mini-lens below the specimen enabling 2nm spatial resolution and only a small residual field at the sample. The combination of high coherence and increased magnification enable quantitative mapping of magnetic induction at the nanometer scale.Electrostatic or magnetic potentials give rise to phase shifts in the holographic interference fringes which can be quantified following reconstruction. In the presence of a magnetic field, the phase equation (for constant composition and neglecting diffraction effects) becomes:
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Yang, Guoliang, Junhong Su, Yuan Li, Jialin Cai, and Yiren Li. "A Study of Resolution Improvement in Noncoherent Optical Coherence Imaging." Advances in Mathematical Physics 2022 (July 5, 2022): 1–12. http://dx.doi.org/10.1155/2022/3232323.

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Noncoherent light, as a common light source in life, can effectively avoid problems such as scattering noise caused by optical components incoherent light imaging, and through the design of the optical path can also trigger interference and holographic imaging of objects, allowing holography to be used in more fields. Various techniques have emerged for recording holograms using incoherent light sources as technology has developed. A recording method has been proposed that exploits the correlation between the object wave information and the Fresnel band sheet to achieve incoherent hologram recording. Using a spatial light modulator (SLM) loaded with a bit-phase mask with multiplexed lens function, the incident light wavefield is phase-modulated to achieve diffraction spectroscopy and phase shifting. And holograms with different phase shifts can be obtained and combined with phase-shifting techniques to eliminate the effects of twin images caused by coaxial holography in the reproduction process. Based on the study of this incoherent holographic imaging system, the influence of the characteristics of the main components of the system and the corresponding parameters on the resolution of the recorded and reproduced holograms is investigated, and optimization methods are given from both theoretical and experimental studies. The empirical analysis of the FINCH imaging system is carried out. The observed optical path is designed, and the method of making a bit-phase mask loaded on a spatial light modulator is presented. The effect of the focal length and recording distance of the dislocation mask on the resolution of the system is investigated by both computer simulation and experimental operation.
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Picart, Pascal. "Recent advances in speckle decorrelation modeling and processing in digital holographic interferometry." Photonics Letters of Poland 13, no. 4 (December 30, 2021): 73. http://dx.doi.org/10.4302/plp.v13i4.1126.

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Digital holography, and especially digital holographic interferometry, is a powerful approach for the characterization of modifications at the surface or in the volume of objects. Nevertheless, the reconstructed phase data from holographic interferometry is corrupted by the speckle noise. In this paper, we discuss on recent advances in speckle decorrelation noise removal. Two main topics are considered. The first one presents recent results in modelling the decorrelation noise in digital Fresnel holography. Especially the anisotropy of the decorrelation noise is established. The second topic presents a new approach for speckle de-noising using deep convolution neural networks. Full Text: PDF ReferencesP. Picart (ed.), New techniques in digital holography (John Wiley & Sons, 2015). CrossRef T.M. Biewer, J.C. Sawyer, C.D. Smith, C.E. Thomas, "Dual laser holography for in situ measurement of plasma facing component erosion (invited)", Rev. Sci. Instr. 89, 10J123 (2018). CrossRef M. Fratz, T. Beckmann, J. Anders, A. Bertz, M. Bayer, T. Gießler, C. Nemeth, D. Carl, "Inline application of digital holography [Invited]", Appl. Opt. 58(34), G120 (2019). CrossRef M.P. Georges, J.-F. Vandenrijt, C. Thizy, Y. Stockman, P. Queeckers, F. Dubois, D. Doyle, "Digital holographic interferometry with CO2 lasers and diffuse illumination applied to large space reflector metrology [Invited]", Appl. Opt. 52(1), A102 (2013). CrossRef E. Meteyer, F. Foucart, M. Secail-Geraud, P. Picart, C. Pezerat, "Full-field force identification with high-speed digital holography", Mech. Syst. Signal Process. 164 (2022). CrossRef L. Lagny, M. Secail-Geraud, J. Le Meur, S. Montresor, K. Heggarty, C. Pezerat, P. Picart, "Visualization of travelling waves propagating in a plate equipped with 2D ABH using wide-field holographic vibrometry", J. Sound Vib. 461 114925 (2019). CrossRef L. Valzania, Y. Zhao, L. Rong, D. Wang, M. Georges, E. Hack, P. Zolliker, "THz coherent lensless imaging", Appl. Opt. 58, G256 (2019). CrossRef V. Bianco, P. Memmolo, M. Leo, S. Montresor, C. Distante, M. Paturzo, P. Picart, B. Javidi, P. Ferraro, "Strategies for reducing speckle noise in digital holography", Light: Sci. Appl. 7(1), 1 (2018). CrossRef V. Bianco, P. Memmolo, M. Paturzo, A. Finizio, B. Javidi, P. Ferraro, "Quasi noise-free digital holography", Light. Sci. Appl. 5(9), e16142 (2016). CrossRef R. Horisaki, R. Takagi, J. Tanida, "Deep-learning-generated holography", Appl. Opt. 57(14), 3859 (2018). CrossRef E. Meteyer, F. Foucart, C. Pezerat, P. Picart, "Modeling of speckle decorrelation in digital Fresnel holographic interferometry", Opt. Expr. 29(22), 36180 (2021). CrossRef M. Piniard, B. Sorrente, G. Hug, P. Picart, "Theoretical analysis of surface-shape-induced decorrelation noise in multi-wavelength digital holography", Opt. Expr. 29(10), 14720 (2021). CrossRef P. Picart, S. Montresor, O. Sakharuk, L. Muravsky, "Refocus criterion based on maximization of the coherence factor in digital three-wavelength holographic interferometry", Opt. Lett. 42(2), 275 (2017). CrossRef P. Picart, J. Leval, "General theoretical formulation of image formation in digital Fresnel holography", J. Opt. Soc. Am. A 25, 1744 (2008). CrossRef S. Montresor, P. Picart, "Quantitative appraisal for noise reduction in digital holographic phase imaging", Opt. Expr. 24(13), 14322 (2016). CrossRef S. Montresor, M. Tahon, A. Laurent, P. Picart, "Computational de-noising based on deep learning for phase data in digital holographic interferometry", APL Photonics 5(3), 030802 (2020). CrossRef M. Tahon, S. Montresor, P. Picart, "Towards Reduced CNNs for De-Noising Phase Images Corrupted with Speckle Noise", Photonics 8(7), 255 (2021). CrossRef E. Meteyer, S. Montresor, F. Foucart, J. Le Meur, K. Heggarty, C. Pezerat, P. Picart, "Lock-in vibration retrieval based on high-speed full-field coherent imaging", Sci. Rep. 11(1), 1 (2021). CrossRef
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Yu, Panpan, Yifan Liu, Yijing Wu, Jinghan Zhuang, Ziqiang Wang, Yinmei Li, and Lei Gong. "Large-FOV scattering-assisted holographic projection by enhanced sampling of transmission matrix." Applied Physics Letters 122, no. 6 (February 6, 2023): 061104. http://dx.doi.org/10.1063/5.0137279.

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Based on wavefront shaping, scattering materials provide a unique tool to break the trade-off between the viewing angle and field of view (FOV) for three-dimensional holographic projections. However, large-size image projection is limited by the low sampling ability of the transmission matrix (TM) of the scattering medium. Here, we propose a disperse and montage sampling strategy to access the TM for large-size image projection by scattering-assisted holography. Compared with the conventional TM sampling methods, our method achieves control of the output field with an enlarged FOV and improved adaptability. Experimentally, we achieve calibration of a TM corresponding to 1920 × 780 output pixels. As a proof of concept, we demonstrate holographic projection of large-size letter images within an area of 11.25 × 4.57 mm2 behind a scattering medium. In addition, we show that large-FOV vectorial projection can also be achieved by sampling the polarization-related TMs. Our work is expected to benefit scattering-assisted holographic techniques with potential applications in holographic display, imaging, and trapping.
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Nam Kim, Nam Kim, Md Ashraful Alam Md. Ashraful Alam, Le Thanh Bang Le Thanh Bang, Anh-Hoang Phan Anh-Hoang Phan, Mei-Lan Piao Mei-Lan Piao, and Munkh-Uchral Erdenebat Munkh-Uchral Erdenebat. "Advances in the light field displays based on integral imaging and holographic techniques (Invited Paper)." Chinese Optics Letters 12, no. 6 (2014): 060005–60009. http://dx.doi.org/10.3788/col201412.060005.

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10

JANG, Jaeduck, Jung Hoon PARK, KyooHyun KIM, Hyeonseung YU, and YongKeun PARK. "Super-resolution Holographic Imaging Techniques Using a Synthetic Aperture." Physics and High Technology 21, no. 5 (May 31, 2012): 27. http://dx.doi.org/10.3938/phit.21.023.

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11

Amineh, Reza K., Maryam Ravan, Raveena Sharma, and Smit Baua. "Three-Dimensional Holographic Imaging Using Single Frequency Microwave Data." International Journal of Antennas and Propagation 2018 (July 17, 2018): 1–14. http://dx.doi.org/10.1155/2018/6542518.

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Three-dimensional (3D) microwave and millimeter wave imaging techniques based on the holographic principles have been successfully employed in several applications such as security screening, body shape measurement for the apparel industry, underground imaging, and wall imaging. The previously proposed 3D holographic imaging techniques require the acquisition of wideband data over rectangular or cylindrical apertures. Requirement for wideband data imposes limitations on the hardware (in particular at very high or very low frequencies). It may also lead to errors in the produced images if the media is dispersive (e.g., in biomedical imaging) and not modeled properly in the image reconstruction process. To address these limitations, here, we propose a technique to perform 3D imaging with single frequency data. Instead of collecting data at multiple frequencies, we acquire the backscattered fields with an array of resonant antennas. We demonstrate the possibility of 3D imaging with the proposed setup and perform a comprehensive study of the capabilities and limitations of the technique via simulations. To perform a realistic study, the simulation data is contaminated by noise.
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Petrov, Viktor, Anastsiya Pogoda, Vladimir Sementin, Alexander Sevryugin, Egor Shalymov, Dmitrii Venediktov, and Vladimir Venediktov. "Advances in Digital Holographic Interferometry." Journal of Imaging 8, no. 7 (July 12, 2022): 196. http://dx.doi.org/10.3390/jimaging8070196.

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Holographic interferometry is a well-established field of science and optical engineering. It has a half-century history of successful implementation as the solution to numerous technical tasks and problems. However, fast progress in digital and computer holography has promoted it to a new level of possibilities and has opened brand new fields of its application. In this review paper, we consider some such new techniques and applications.
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Smith, D., M. Leach, and A. J. Sambell. "Microwave indirect holographic imaging using an adaptation of optical techniques." IEEE Microwave and Wireless Components Letters 13, no. 9 (September 2003): 379–81. http://dx.doi.org/10.1109/lmwc.2003.817134.

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14

Poon, Ting-Chung, Yaping Zhang, Liangcai Cao, and Hiroshi Yoshikawa. "Editorial on Special Issue “Holography, 3-D Imaging and 3-D Display”." Applied Sciences 10, no. 20 (October 11, 2020): 7057. http://dx.doi.org/10.3390/app10207057.

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Modern holographic techniques have been successfully applied in many important areas, such as 3D inspection, 3D microscopy, metrology and profilometry, augmented reality, and industrial informatics [...]
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Gao, Yuki, Maryam Ravan, and Reza K. Amineh. "Fast, Robust, and Low-Cost Microwave Imaging of Multiple Non-Metallic Pipes." Electronics 10, no. 15 (July 23, 2021): 1762. http://dx.doi.org/10.3390/electronics10151762.

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The use of non-metallic pipes and composite components that are low-cost, durable, light-weight, and resilient to corrosion is growing rapidly in various industrial sectors such as oil and gas industries in the form of non-metallic composite pipes. While these components are still prone to damages, traditional non-destructive testing (NDT) techniques such as eddy current technique and magnetic flux leakage technique cannot be utilized for inspection of these components. Microwave imaging can fill this gap as a favorable technique to perform inspection of non-metallic pipes. Holographic microwave imaging techniques are fast and robust and have been successfully employed in applications such as airport security screening and underground imaging. Here, we extend the use of holographic microwave imaging to inspection of multiple concentric pipes. To increase the speed of data acquisition, we utilize antenna arrays along the azimuthal direction in a cylindrical setup. A parametric study and demonstration of the performance of the proposed imaging system will be provided.
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Model, Michael A. "Imaging the Cell's Third Dimension." Microscopy Today 20, no. 3 (May 2012): 32–37. http://dx.doi.org/10.1017/s1551929512000247.

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Shape and size are among the most basic and obvious characteristics of a cell (or of any physical object, for that matter). When a cell is observed through a microscope, one only sees its projection onto the image plane. Rather paradoxically, there are no easy techniques to visualize and measure cell's third dimension—thickness. For example, confocal microscopy requires fluorescent labeling, multiple scanning with a high-power objective, possibly correction for the refractive index mismatch, and even then, generation of a complete three-dimensional profile is not very straightforward or precise. Other techniques for imaging the cell vertical profile, such as ion conductance, digital holographic, or atomic force microscopy, are rather complex and not available to most users.
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Baek, YoonSeok, KyeoReh Lee, Jeonghun Oh, and YongKeun Park. "Speckle-Correlation Scattering Matrix Approaches for Imaging and Sensing through Turbidity." Sensors 20, no. 11 (June 2, 2020): 3147. http://dx.doi.org/10.3390/s20113147.

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The development of optical and computational techniques has enabled imaging without the need for traditional optical imaging systems. Modern lensless imaging techniques overcome several restrictions imposed by lenses, while preserving or even surpassing the capability of lens-based imaging. However, existing lensless methods often rely on a priori information about objects or imaging conditions. Thus, they are not ideal for general imaging purposes. The recent development of the speckle-correlation scattering matrix (SSM) techniques facilitates new opportunities for lensless imaging and sensing. In this review, we present the fundamentals of SSM methods and highlight recent implementations for holographic imaging, microscopy, optical mode demultiplexing, and quantification of the degree of the coherence of light. We conclude with a discussion of the potential of SSM and future research directions.
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Smith, D., M. Leach, M. Elsdon, and S. Foti. "Indirect Holographic Techniques for Determining Antenna Radiation Characteristics and Imaging Aperture Fields." IEEE Antennas and Propagation Magazine 49, no. 1 (February 2007): 54–67. http://dx.doi.org/10.1109/map.2007.370982.

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Sun, H., P. W. Benzie, N. Burns, D. C. Hendry, M. A. Player, and J. Watson. "Underwater digital holography for studies of marine plankton." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 366, no. 1871 (January 25, 2008): 1789–806. http://dx.doi.org/10.1098/rsta.2007.2187.

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Conventional and digital holographies are proving to be increasingly important for studies of marine zooplankton and other underwater biological applications. This paper reports on the use of a subsea digital holographic camera (eHoloCam) for the analysis and identification of marine organisms and other subsea particles. Unlike recording on a photographic film, a digital hologram (e-hologram) is recorded on an electronic sensor and reconstructed numerically in a computer by simulating the propagation of the optical field in space. By comparison with other imaging techniques, an e-hologram has several advantages such as three-dimensional spatial reconstruction, non-intrusive and non-destructive interrogation of the recording sampling volume and the ability to record holographic videos. The basis of much work in optics lies in Maxwell's electromagnetic theory and holography is no exception: we report here on two of the numerical reconstruction algorithms we have used to reconstruct holograms obtained using eHoloCam and how their starting point lies in Maxwell's equations. Derivation of the angular spectrum algorithm for plane waves is provided as an exact method for the in-line numerical reconstruction of digital holograms. The Fresnel numerical reconstruction algorithm is derived from the angular spectrum method. In-line holograms are numerically processed before and after reconstruction to remove periodic noise from captured images and to increase image contrast. The ability of the Fresnel integration reconstruction algorithm to extend the reconstructed volume beyond the recording sensor dimensions is also shown with a 50% extension of the reconstruction area. Finally, we present some images obtained from recent deployments of eHoloCam in the North Sea and Faeroes Channel.
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Hagemann, Johannes, and Tim Salditt. "The fluence–resolution relationship in holographic and coherent diffractive imaging." Journal of Applied Crystallography 50, no. 2 (March 22, 2017): 531–38. http://dx.doi.org/10.1107/s1600576717003065.

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This work presents a numerical study of the fluence–resolution behaviour for two coherent lensless X-ray imaging techniques. To this end the fluence–resolution relationship of inline near-field holography and far-field coherent diffractive imaging are compared in numerical experiments. To achieve this, the phase reconstruction is carried out using iterative phase-retrieval algorithms on simulated noisy data. Using the incident photon fluence on the specimen as the control parameter, the achievable resolution for two example phantoms (cell and bitmap) is studied. The results indicate the superior performance of holography compared with coherent diffractive imaging, for the same fluence and phase-reconstruction procedure.
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Reddy, B. Lokesh, and Anith Nelleri. "Convex optimization for additive noise reduction in quantitative complex object wave retrieval using compressive off-axis digital holographic imaging." Journal of Intelligent Systems 31, no. 1 (January 1, 2022): 706–15. http://dx.doi.org/10.1515/jisys-2022-0043.

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Abstract Image denoising is one of the important problems in the research field of computer vision, artificial intelligence, 3D vision, and image processing, where the fundamental aim is to recover the original image features from a noisy contaminated image. The camera sensor additive noise present in the holographic recording process reduces the quality of the retrieved image. Even though various techniques have been developed to minimize the noise in digital holography, the noise reduction still remains a challenging task. This article presents a compressive sensing (CS) technique to minimize the additive noise in the digital holographic reconstruction process. We demonstrate the reduction of additive noise using complex wave retrieval method as a sensing matrix in the CS model. The proposed CS method to suppress the noise during the reconstruction process is illustrated using numerical simulations. Only 50% of the pixel measurements are considered in the noisy hologram, which is far less than the original complex object pixels. The impact of additive gaussian noise in the recording plane on the reconstruction accuracy of both intensity and phase distribution is analysed. The CS method denoises and estimates the complex object information accurately. The numerical simulation results have shown that the proposed CS method has effectively minimized the noise in the reconstructed image and has greatly improved the quality of both intensity and phase information.
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Fioranelli, Massimo, Aroonkumar Beesham, and Alireza Sepehri. "A Proposal for an Ultrasound/Sound Holographic Microscope Using Entangled Mobile Phone Inductors." Ultrasound International Open 08, no. 02 (November 2022): E53—E58. http://dx.doi.org/10.1055/a-1932-8287.

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AbstractIn this study we propose a model for building a holographic ultrasound microscope. In this model two mobile phones are first connected by waves and techniques like the WhatsApp waves. If the mobile phones are close to each other, their inductors and speakers become entangled, they exchange electromagnetic and sound waves, and they vibrate many times with each other. Objects placed between two mobile phones change the sound waves and electromagnetic waves and appear as holographic images within the inductors and also on the plastic of the speakers. To see these images, a hologram machine is built from a room of plastic, one or two magnets, iron particles, and sound producers. Holographic waves change the magnetic field within the hologram machine and move the plastic and iron particles. These objects take the shape of waves and produce holographic images. To see microbes, one can send a weak current to a container of microbes and then connect it to an amplifier. The weak current takes the shape of the microbes and is amplified by one strong amplifier. Then this current goes to the mobile phone and sound card and, after passing some stages, is sent to the second mobile phone. In the second mobile phone, the sound wave is amplified by speakers and transmitted to the hologram machine. Consequently, particles within this machine move and produce big holographic images of the microbes.
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Nygate, Yoav N., Mattan Levi, Simcha K. Mirsky, Nir A. Turko, Moran Rubin, Itay Barnea, Gili Dardikman-Yoffe, Miki Haifler, Alon Shalev, and Natan T. Shaked. "Holographic virtual staining of individual biological cells." Proceedings of the National Academy of Sciences 117, no. 17 (April 13, 2020): 9223–31. http://dx.doi.org/10.1073/pnas.1919569117.

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Many medical and biological protocols for analyzing individual biological cells involve morphological evaluation based on cell staining, designed to enhance imaging contrast and enable clinicians and biologists to differentiate between various cell organelles. However, cell staining is not always allowed in certain medical procedures. In other cases, staining may be time-consuming or expensive to implement. Staining protocols may be operator-sensitive, and hence may lead to varying analytical results, as well as cause artificial imaging artifacts or false heterogeneity. We present a deep-learning approach, called HoloStain, which converts images of isolated biological cells acquired without staining by holographic microscopy to their virtually stained images. We demonstrate this approach for human sperm cells, as there is a well-established protocol and global standardization for characterizing the morphology of stained human sperm cells for fertility evaluation, but, on the other hand, staining might be cytotoxic and thus is not allowed during human in vitro fertilization (IVF). After a training process, the deep neural network can take images of unseen sperm cells retrieved from holograms acquired without staining and convert them to their stainlike images. We obtained a fivefold recall improvement in the analysis results, demonstrating the advantage of using virtual staining for sperm cell analysis. With the introduction of simple holographic imaging methods in clinical settings, the proposed method has a great potential to become a common practice in human IVF procedures, as well as to significantly simplify and radically change other cell analyses and techniques such as imaging flow cytometry.
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De Angelis, A., S. Managò, M. A. Ferrara, M. Napolitano, G. Coppola, and A. C. De Luca. "Combined Raman Spectroscopy and Digital Holographic Microscopy for Sperm Cell Quality Analysis." Journal of Spectroscopy 2017 (2017): 1–14. http://dx.doi.org/10.1155/2017/9876063.

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The diagnosis of male infertility is vastly complex. To date, morphology, motility, and concentration have been used as key parameters to establish the sperm normality and achieve pregnancy both in natural and in assisted fecundation. However, spermatozoa from infertile men could present a variety of alterations, such as DNA fragmentation, alterations of chromatin structure, and aneuploidy, which have been demonstrated to decrease reproductive capacity of men. Therefore, the ability to see detailed relationships between morphology and physiology in selected spermatozoa with submicrometric resolution in a nondestructive and noninvasive way and within a functional correlated context could be extremely important for the intracytoplasmic sperm injection procedure. In this review, we describe label-free optical spectroscopy and imaging techniques, based on the combination of Raman spectroscopy/imaging with holographic imaging, which are able to noninvasively measure the (bio)chemistry and morphology of sperm cells. We discuss the benefits and limitation of the proposed photonic techniques, with particular emphasis on applications in detection/characterization of sperm cell morphological defects and photodamage, and the identification/sorting of X- and Y-bearing bovine spermatozoa.
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Coppola, Giuseppe, and Maria Antonietta Ferrara. "Polarization-Sensitive Digital Holographic Imaging for Characterization of Microscopic Samples: Recent Advances and Perspectives." Applied Sciences 10, no. 13 (June 29, 2020): 4520. http://dx.doi.org/10.3390/app10134520.

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Polarization-sensitive digital holographic imaging (PS-DHI) is a recent imaging technique based on interference among several polarized optical beams. PS-DHI allows simultaneous quantitative three-dimensional reconstruction and quantitative evaluation of polarization properties of a given sample with micrometer scale resolution. Since this technique is very fast and does not require labels/markers, it finds application in several fields, from biology to microelectronics and micro-photonics. In this paper, a comprehensive review of the state-of-the-art of PS-DHI techniques, the theoretical principles, and important applications are reported.
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Brunnhofer, Georg, Isabella Hinterleitner, Alexander Bergmann, and Martin Kraft. "A Comparison of Different Counting Methods for a Holographic Particle Counter: Designs, Validations and Results." Sensors 20, no. 10 (May 25, 2020): 3006. http://dx.doi.org/10.3390/s20103006.

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Digital Inline Holography (DIH) is used in many fields of Three-Dimensional (3D) imaging to locate micro or nano-particles in a volume and determine their size, shape or trajectories. A variety of different wavefront reconstruction approaches have been developed for 3D profiling and tracking to study particles’ morphology or visualize flow fields. The novel application of Holographic Particle Counters (HPCs) requires observing particle densities in a given sampling volume which does not strictly necessitate the reconstruction of particles. Such typically spherical objects yield circular intereference patterns—also referred to as fringe patterns—at the hologram plane which can be detected by simpler Two-Dimensional (2D) image processing means. The determination of particle number concentrations (number of particles/unit volume [#/cm 3 ]) may therefore be based on the counting of fringe patterns at the hologram plane. In this work, we explain the nature of fringe patterns and extract the most relevant features provided at the hologram plane. The features aid the identification and selection of suitable pattern recognition techniques and its parameterization. We then present three different techniques which are customized for the detection and counting of fringe patterns and compare them in terms of detection performance and computational speed.
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Takeda, Mitsuo, Alok Kumar Singh, Dinesh Narayana Naik, Giancarlo Pedrini, and Wolfgang Osten. "Holographic Correloscopy—Unconventional Holographic Techniques For Imaging a Three-Dimensional Object Through an Opaque Diffuser or Via a Scattering Wall: A Review." IEEE Transactions on Industrial Informatics 12, no. 4 (August 2016): 1631–40. http://dx.doi.org/10.1109/tii.2015.2503641.

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Spring, K. R. "Multispectral Imaging in Light Microscopy." Microscopy and Microanalysis 4, S2 (July 1998): 126–27. http://dx.doi.org/10.1017/s1431927600020754.

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Many recent applications in light microscopy involve the use of multiple fluorophores or the delineation of signals arising from spectrally distinct sources. In microspectroscopy, it is always desirable to illuminate fluorescently-labeled microscopic specimens with monochromatic light as the narrowest possible excitation wavelength range usually results in the highest emission signal-to-noise ratio. Generation of polychromatic light from an arc lamp and selection of the excitation wavelength by interference filters or monochrometers are the most common techniques for excitation microspectrofluorometry. Emission spectroscopy is usually done with filter wheels, monochrometers, or interferometers inserted between the microscope detection port and the detector. This presentation will be directed toward other, less frequently-used, approaches for spectral scanning of the specimen in the light microscope. Three topics will be considered: 1) the use of acousto-optical tunable filters and lasers for rapid, narrow-band, excitation wavelength selection; 2) the use of holographic notch filters for rejection of unwanted excitation laser light; 3) using liquid-crystal tunable filters for emission scanning.
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29

Kuś, Arkadiusz, Wojciech Krauze, and Małgorzata Kujawińska. "From digital holographic microscopy to optical coherence tomography – separate past and a common goal." Photonics Letters of Poland 13, no. 4 (December 30, 2021): 91. http://dx.doi.org/10.4302/plp.v13i4.1130.

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In this paper we briefly present the history and outlook on the development of two seemingly distant techniques which may be brought close together with a unified theoretical model described as common k-space theory. This theory also known as the Fourier diffraction theorem is much less common in optical coherence tomography than its traditional mathematical model, but it has been extensively studied in digital holography and, more importantly, optical diffraction tomography. As demonstrated with several examples, this link is one of the important factors for future development of both techniques. Full Text: PDF ReferencesN. Leith, J. Upatnieks, "Reconstructed Wavefronts and Communication Theory", J. Opt. Soc. Am. 52(10), 1123 (1962). CrossRef Y. Park, C. Depeursinge, G. Popescu, "Quantitative phase imaging in biomedicine", Nat. Photonics 12, 578 (2018). CrossRef D. Huang et al., "Optical Coherence Tomography", Science 254(5035), 1178 (1991). CrossRef D. P. Popescu, C. Flueraru, S. Chang, J. Disano, S. Sherif, M.G. Sowa, "Optical coherence tomography: fundamental principles, instrumental designs and biomedical applications", Biophys. Rev. 3(3), 155 (2011). CrossRef M. Wojtkowski, V. Srinivasan, J.G. Fujimoto, T. Ko, J.S. Schuman, A. Kowalczyk, J.S. Duker, "Three-dimensional Retinal Imaging with High-Speed Ultrahigh-Resolution Optical Coherence Tomography", Ophthalmology 112(10), 1734 (2005). CrossRef K.C. Zhou, R. Qian, A.-H. Dhalla, S. Farsiu, J.A. Izatt, "Unified k-space theory of optical coherence tomography", Adv. Opt. Photon. 13(2), 462 (2021). CrossRef A.F. Fercher, C.K. Hitzenberger, G. Kamp, S.Y. El-Zaiat, "Measurement of intraocular distances by backscattering spectral interferometry", Opt. Comm. 117(1-2), 43 (1995). CrossRef E. Wolf, "Determination of the Amplitude and the Phase of Scattered Fields by Holography", J. Opt. Soc. Am. 60(1), 18 (1970). CrossRef E. Wolf, "Three-dimensional structure determination of semi-transparent objects from holographic data", Opt. Comm. 1(4), 153 (1969). CrossRef V. Balasubramani et al., "Roadmap on Digital Holography-Based Quantitative Phase Imaging", J. Imaging 7(12), 252 (2021). CrossRef A. Kuś, W. Krauze, P.L. Makowski, M. Kujawińska, "Holographic tomography: hardware and software solutions for 3D quantitative biomedical imaging (Invited paper)", ETRI J. 41(1), 61 (2019). CrossRef A. Kuś, M. Dudek, M. Kujawińska, B. Kemper, A. Vollmer, "Tomographic phase microscopy of living three-dimensional cell cultures", J. Biomed. Opt. 19(4), 46009 (2014). CrossRef O. Haeberlé, K. Belkebir, H. Giovaninni, A. Sentenac, "Tomographic diffractive microscopy: basics, techniques and perspectives", J. Mod. Opt. 57(9), 686 (2010). CrossRef B. Simon et al., "Tomographic diffractive microscopy with isotropic resolution", Optica 4(4), 460 (2017). CrossRef B.A. Roberts, A.C. Kak, "Reflection Mode Diffraction Tomography", Ultrason. Imag. 7, 300 (1985). CrossRef M. Sarmis et al., "High resolution reflection tomographic diffractive microscopy", J. Mod. Opt. 57(9), 740 (2010). CrossRef L. Foucault et al., "Versatile transmission/reflection tomographic diffractive microscopy approach", J. Opt. Soc. Am. A 36(11), C18 (2019). CrossRef W. Krauze, P. Ossowski, M. Nowakowski, M. Szkulmowski, M. Kujawińska, "Enhanced QPI functionality by combining OCT and ODT methods", Proc. SPIE 11653, 116530B (2021). CrossRef E. Mudry, P.C. Chaumet, K. Belkebir, G. Maire, A. Sentenac, "Mirror-assisted tomographic diffractive microscopy with isotropic resolution", Opt. Lett. 35(11), 1857 (2010). CrossRef P. Hosseini, Y. Sung, Y. Choi, N. Lue, Z. Yaqoob, P. So, "Scanning color optical tomography (SCOT)", Opt. Expr. 23(15), 19752 (2015). CrossRef J. Jung, K. Kim, J. Yoon, Y. Park, "Hyperspectral optical diffraction tomography", Opt. Expr. 24(3), 1881 (2016). CrossRef T. Zhang et al., Biomed. "Multi-wavelength multi-angle reflection tomography", Opt. Expr. 26(20), 26093 (2018). CrossRef R.A. Leitgeb, "En face optical coherence tomography: a technology review [Invited]", Biomed. Opt. Expr. 10(5), 2177 (2019). CrossRef J.F. de Boer, R. Leitgeb, M. Wojtkowski, "Twenty-five years of optical coherence tomography: the paradigm shift in sensitivity and speed provided by Fourier domain OCT [Invited]", Biomed. Opt. Expr. 8(7), 3248 (2017). CrossRef T. Anna, V. Srivastava, C. Shakher, "Transmission Mode Full-Field Swept-Source Optical Coherence Tomography for Simultaneous Amplitude and Quantitative Phase Imaging of Transparent Objects", IEEE Photon. Technol. Lett. 23(11), 899 (2011). CrossRef M.T. Rinehart, V. Jaedicke, A. Wax, "Quantitative phase microscopy with off-axis optical coherence tomography", Opt. Lett. 39(7), 1996 (2014). CrossRef C. Photiou, C. Pitris, "Dual-angle optical coherence tomography for index of refraction estimation using rigid registration and cross-correlation", J. Biomed. Opt. 24(10), 1 (2019). CrossRef Y. Zhou, K.K.H. Chan, T. Lai, S. Tang, "Characterizing refractive index and thickness of biological tissues using combined multiphoton microscopy and optical coherence tomography", Biomed. Opt. Expr. 4(1), 38 (2013). CrossRef K.C. Zhou, R. Qian, S. Degan, S. Farsiu, J.A. Izatt, "Optical coherence refraction tomography", Nat. Photon. 13, 794 (2019). CrossRef
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30

Scharf, Elias, Robert Kuschmierz, and Jürgen Czarske. "Holographic lensless fiber endoscope with needle size using self-calibration." tm - Technisches Messen 86, no. 3 (March 26, 2019): 144–50. http://dx.doi.org/10.1515/teme-2018-0087.

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AbstractEndoscopes enable optical keyhole access in many applications for instance in biomedicine. In general, coherent fiber bundles (CFB) are used in conjunction with rigid lens systems which determine a fixed image plane. However, the lens system limits the minimum diameter of the endoscope typically to several millimeters. Additionally, only pixelated two-dimensional amplitude patterns can be transferred due to phase scrambling between adjacent cores. These limitations can be overcome by digital optical elements. Thus, in principle thinner, lensless, holographic endoscopes with a three-dimensional adjustable focus for imaging and illumination can be realized. So far, several techniques based on single mode CFB and multi mode fibers (MMF) have been presented. However, these techniques require access to both sides of the fiber, in order to calibrate the bending and temperature sensitive phase distortion, which is not possible in a real application. We present the feasibility of an in-situ calibration and compensation of a CFB with single sided access. A lensless endoscope with a diameter of only 500 µm, a spatial resolution around 1 µm and video rate capability is realized.
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31

Charatis, G., G. E. Busch, B. K. F. Young, and R. E. Stewart. "Diagnostic Characterization of Laser-Irradiated dot Targets." International Astronomical Union Colloquium 102 (1988): 375–78. http://dx.doi.org/10.1017/s0252921100108139.

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AbstractWe have conducted a series of experiments at the KMS CHROMA facility using dot spectroscopy techniques to characterize uncertainties associated with spectral line ratio models commonly applied in determining electron temperatures and densities. Temperatures determined from the slope of the H-like free-bound continuum and densities via holographic interferometry, are compared to line ratio methods. Dot targets of (typically 100µmD Mg or Al) are irradiated with 2 to 40 × 1013W/cm2of 0.53µmlight. Time and spatial gradients are resolved using 4 diagnostics: a 4-frame holographic interferometer, an x-ray streak crystal spectrograph with a spatial imaging slit, a framing crystal x-ray spectrometer, and a conventional space-resolved time-integrating crystal spectrograph used for survey and calibration purposes. Preliminary results indicate the ionization distribution of these laser produced plasmas is not steady-state which plays an important role in measuring the temperature and and density. Electron temperatures derived from line-ratio techniques, assuming steady state conditions, disagree dramatically from simultaneous measurements using the slope of the H-like continuum. Electron densities using He-like triplet to singlet line ratios also differ from densities measured interferometrically.
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32

Coened, W. M. J., A. J. E. M. Janssend, M. Op de Beeck, D. Van Dyck, E. J. Van Zwet, and H. W. Zandbergen. "Focus-variation image reconstruction in field-emission TEM." Proceedings, annual meeting, Electron Microscopy Society of America 51 (August 1, 1993): 1070–71. http://dx.doi.org/10.1017/s0424820100151180.

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The use of a field emission gun (FEG) in high resolution TEM (HRTEM) improves the information limit much below the point resolution. This is due to the FEG’s high brightness and low energy spread which yield a very good coherence. In the area between point and information resolution of the FEG-TEM, image interpretation is complicated by the lens aberrations and focus effects, which cause scrambling of the information from the specimen. This problem is solved by ‘holographic’ techniques, which retrieve aberration-corrected amplitude and phase information of the electron wave ϕ at the exit plane of the specimen. We follow the route of ‘in-column’ or ‘nonlinear’ holography by digital processing of a focal series of HRTEM images. Different reconstruction algorithms can be used for that purpose depending on the assumptions that are made in the HRTEM imaging model. We have devised two workable algorithms. A first method, called the “paraboloid method” (PAM), aims at filtering out recursively the nonlinear contributions in the images, so that high-speed linear reconstruction can be applied.
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33

Touloupas, Georgios, Annika Lauber, Jan Henneberger, Alexander Beck, and Aurélien Lucchi. "A convolutional neural network for classifying cloud particles recorded by imaging probes." Atmospheric Measurement Techniques 13, no. 5 (May 8, 2020): 2219–39. http://dx.doi.org/10.5194/amt-13-2219-2020.

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Abstract. During typical field campaigns, millions of cloud particle images are captured with imaging probes. Our interest lies in classifying these particles in order to compute the statistics needed for understanding clouds. Given the large volume of collected data, this raises the need for an automated classification approach. Traditional classification methods that require extracting features manually (e.g., decision trees and support vector machines) show reasonable performance when trained and tested on data coming from a unique dataset. However, they often have difficulties in generalizing to test sets coming from other datasets where the distribution of the features might be significantly different. In practice, we found that for holographic imagers each new dataset requires labeling a huge amount of data by hand using those methods. Convolutional neural networks have the potential to overcome this problem due to their ability to learn complex nonlinear models directly from the images instead of pre-engineered features, as well as by relying on powerful regularization techniques. We show empirically that a convolutional neural network trained on cloud particles from holographic imagers generalizes well to unseen datasets. Moreover, fine tuning the same network with a small number (256) of training images improves the classification accuracy. Thus, the automated classification with a convolutional neural network not only reduces the hand-labeling effort for new datasets but is also no longer the main error source for the classification of small particles.
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34

Yamamoto, Kazuo, Tsukasa Hirayama, and Takayoshi Tanji. "Development of advanced electron holographic techniques and application to industrial materials and devices." Microscopy 62, suppl 1 (March 26, 2013): S29—S41. http://dx.doi.org/10.1093/jmicro/dft006.

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35

Chan, Huang-Tian, and Chi-Ching Chang. "Decryption of Deterministic Phase-Encoded Digital Holography Using Convolutional Neural Networks." Photonics 10, no. 6 (May 25, 2023): 612. http://dx.doi.org/10.3390/photonics10060612.

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Digital holographic encryption is an important information security technology. Traditional encryption techniques require the use of keys to encrypt information. If the key is lost, it is difficult to recover information, so new technologies that allow legitimate authorized users to access information are necessary. This study encrypts fingerprints and other data using a deterministic phase-encoded encryption system that uses digital holography (DPDH) and determines whether decryption is possible using a convolutional neural network (CNN) using the U-net model. The U-net is trained using a series of ciphertext-plaintext pairs. The results show that the U-net model decrypts and reconstructs images and that the proposed CNN defeats the encryption system. The corresponding plaintext (fingerprint) is retrieved from the ciphertext without using the key so that the proposed method performs well in terms of decryption. The proposed scheme simplifies the decryption process and can be used for information security risk assessment.
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36

Rogers, Brian, Tatsiana Mikulchyk, Mohamed Oubaha, Dervil Cody, Suzanne Martin, and Izabela Naydenova. "Improving the Holographic Recording Characteristics of a Water-Resistant Photosensitive Sol–Gel for Use in Volume Holographic Optical Elements." Photonics 9, no. 9 (September 4, 2022): 636. http://dx.doi.org/10.3390/photonics9090636.

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Continual improvements to holographic recording materials make the development of volume holographic optical elements increasingly more attainable for applications where highly efficient, lightweight diffractive optical elements can replace conventional optics. A fast-curing, water resistant photosensitive sol–gel capable of volume holographic recording has recently drawn attention for its extreme environmental and physical robustness, in particular its water/moisture and scratch resistance. However, to date, the refractive index modulation has been limited. While water-resistant properties are invaluable in the face of the weathering which many practical systems for outdoor applications will endure, high refractive index modulation is also important in order to facilitate high diffraction efficiency holograms recorded in relatively thin layers. Lower grating thickness ensures a large angular and wavelength range of operation-properties that are critical for many applications of holographic optical elements such as solar light harvesting, optical displays and illumination management. For any application where low-cost mass production is envisaged, sensitivity/writing speed is also a crucial factor. In this research, we studied the recording properties of these water-resistant photosensitive sol–gel layers at two different recording wavelengths (532 and 476 nm) and investigated methods for improving these properties. We report more than two-fold improvement of the refractive index modulation from 1.4×10−3 to 3.3×10−3 in layers of thickness ranging from 40–100 μm and more than an order of magnitude increase in photosensitivity/recording speed through better matching between recording wavelength and layer absorption, chemical alterations and thermal post-processing techniques.
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37

Phan, Robert, Michael P. Chae, David J. Hunter-Smith, and Warren Matthew Rozen. "Advances in perforator imaging through holographic CTA and augmented reality: a systematic review." Australasian Journal of Plastic Surgery 5, no. 1 (March 31, 2022): 32–38. http://dx.doi.org/10.34239/ajops.v5n1.263.

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Introduction: Free tissue transfer has become a mainstay in reconstructive plastic surgery, and techniques to plan such surgery continue to evolve. Novel technologies and increases in computational power have enabled computed tomographic angiography (CTA)data augmentation onto patients to assist in pedicle identification and dissection. Given the rapidly evolving field and research in this domain, a systematic re-view was undertaken to establish the evidence for its usefulness in pedicle identification and dissection. Methods: An extensive search using keywords in EMBASE and PubMed with bibliographic linkage following PRISMA guidelines was performed. 107 articles were identified. Duplicate articles were removed prior to review. Two reviewers independently screened the titles for appropriate topic relevance. Full articles were then screened for review. Results: Eleven articles were appropriate for review. Two articles analysed the time taken to identify perfo-rators using augmented reality (AR) compared to Doppler ultrasound. The remainder of the articles ana-lysed time to perforator identification, differences between projected location and dissected perforator location, qualitative feedback from surgeons on the use of AR systems for perforator identification and proof of concept and the usefulness of AR in perforator flap surgery. Conclusion: This review demonstrates that while established methods of data rendering and projection can achieve holographic projection and AR, there is a lack of objective outcome data to demonstrate its usefulness. This, combined with a cost analysis, are the main obstructions to this technology being more widely adopted.
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Novta, Evgenije, Tijana Lainovic, Dusan Grujic, Jelena Komsic, Dejan Pantelic, and Larisa Blazic. "Novel biophotonics-based techniques in dental medicine - a literature review." Medical review 73, no. 11-12 (2020): 364–68. http://dx.doi.org/10.2298/mpns2012364n.

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Introduction. Biophotonics deals with interactions between light and biological matter, integrating knowledge of physics, chemistry, engineering, biology, and medicine for solving specific biomedical or life science problems. Due to the ability to provide non-invasive, highly sensitive tissue information and inducing specific localized tissue ablation, biophotonics-based technologies may be of utmost importance in improving dental healthcare. The aim of this review article is to give an overview of contemporary biophotonics-based technologies and their applications in dental research and clinical practice. Various applications of biophotonics-based technologies. Biomedical imaging techniques (nonlinear microscopy methods and optical coherence tomography), photo-mechanical methods (digital holographic interferometry, photo-elasticity, digital image correlation, Moir? interferometry), optical spectroscopy techniques (Raman and Fourier transform infrared spectroscopy, Brillouin light scattering spectroscopy), fiber Bragg grating sensors, photodynamic therapy, photo-biostimulation, and femtosecond laser applications are presented in this paper. Conclusion. In accordance with the modern tendencies of prevention and timely diagnosis of oral diseases, biophotonics may be considered the leading scientific discipline on the path of progress of dental medicine and technology. Therefore, this paper provides an overview of modern methods based on biophotonics and summarizes their applicability focusing on the field of dental medicine.
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39

Jonsson, P., I. Sillitoe, B. Dushaw, J. Nystuen, and J. Heltne. "Observing using sound and light – a short review of underwater acoustic and video-based methods." Ocean Science Discussions 6, no. 1 (April 29, 2009): 819–70. http://dx.doi.org/10.5194/osd-6-819-2009.

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Abstract. This paper is a review which briefly describes a selection of acoustic observation techniques and certain aspects of underwater video technology suitable for observations in an underwater environment. The review is divided into two sections, one for each subject, where each section concludes with a discussion of the current challenges within the respective fields. The acoustic section of the review covers bathymetric and geometrical measurements, imaging sonars, subsurface penetrating profilers, positioning methods, acoustic underwater communication and sensor networks, and water speed measurements. The section ends by considering temperature measurements by ocean acoustic tomography and passive acoustic monitoring. The underwater video section initially deals with questions of acquisition including underwater visibility, the type of platform, and video formats, image sensors and specialized cameras. This is followed by notes on processing techniques including mosaicking, stereo video, structured light, recording and transmission, image enhancement techniques and ends with a short discussion of underwater holographic cameras.
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40

Chang, Chi-Ching, Yang-Kun Chew, Huang-Tian Chan, Mei-Fang Chou, and Je-Chung Wang. "Image Contrast Improvement in Interference-Dark-Field Digital Holographic Microscopy." Photonics 8, no. 11 (November 17, 2021): 517. http://dx.doi.org/10.3390/photonics8110517.

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Conventional dark-field digital holographic microscopy (DHM) techniques require the use of specialized optics, and, thus, obtaining dark-field images with high contrast has a high cost. Herein, we propose a DHM system that uses an interference-dark-field technique for improving image contrast. Unlike conventional dark-field DHM, the proposed technique does not require expensive and specialized optical elements, or a complicated optical setup, to obtain dark-field images. The proposed technique employs a pure optical basis method to suppress scattering noise—namely, interference-dark-field—and mainly adopts an arbitrary micro-phase shifting method to achieve destructive interference for obtaining holograms. Under the framework of the proposed technique and through the observation of the USAF 1951 resolution target, the reconstructed image can retain the high contrast of the interference-dark-field DHM. The image contrast is enhanced by at least 43% compared to that which is obtained by conventional dark-field DHM. The resolution of the system can be as high as 0.87 μm. The proposed technique can switch between bright-field and dark-field DHM and prevents damage to the sample, which results from high-intensity illumination in conventional techniques.
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Buzalewicz, Igor, Agnieszka Ulatowska-Jarża, Aleksandra Kaczorowska, Marlena Gąsior-Głogowska, Halina Podbielska, Magdalena Karwańska, Alina Wieliczko, Anna K. Matczuk, Katarzyna Kowal, and Marta Kopaczyńska. "Bacteria Single-Cell and Photosensitizer Interaction Revealed by Quantitative Phase Imaging." International Journal of Molecular Sciences 22, no. 10 (May 11, 2021): 5068. http://dx.doi.org/10.3390/ijms22105068.

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Quantifying changes in bacteria cells in the presence of antibacterial treatment is one of the main challenges facing contemporary medicine; it is a challenge that is relevant for tackling issues pertaining to bacterial biofilm formation that substantially decreases susceptibility to biocidal agents. Three-dimensional label-free imaging and quantitative analysis of bacteria–photosensitizer interactions, crucial for antimicrobial photodynamic therapy, is still limited due to the use of conventional imaging techniques. We present a new method for investigating the alterations in living cells and quantitatively analyzing the process of bacteria photodynamic inactivation. Digital holographic tomography (DHT) was used for in situ examination of the response of Escherichia coli and Staphylococcus aureus to the accumulation of the photosensitizers immobilized in the copolymer revealed by the changes in the 3D refractive index distributions of single cells. Obtained results were confirmed by confocal microscopy and statistical analysis. We demonstrated that DHT enables real-time characterization of the subcellular structures, the biophysical processes, and the induced local changes of the intracellular density in a label-free manner and at sub-micrometer spatial resolution.
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42

Kang, Sok-Leng, and Lee Benson. "Recent advances in cardiac catheterization for congenital heart disease." F1000Research 7 (March 26, 2018): 370. http://dx.doi.org/10.12688/f1000research.13021.1.

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The field of pediatric and adult congenital cardiac catheterization has evolved rapidly in recent years. This review will focus on some of the newer endovascular technological and management strategies now being applied in the pediatric interventional laboratory. Emerging imaging techniques such as three-dimensional (3D) rotational angiography, multi-modal image fusion, 3D printing, and holographic imaging have the potential to enhance our understanding of complex congenital heart lesions for diagnostic or interventional purposes. While fluoroscopy and standard angiography remain procedural cornerstones, improved equipment design has allowed for effective radiation exposure reduction strategies. Innovations in device design and implantation techniques have enabled the application of percutaneous therapies in a wider range of patients, especially those with prohibitive surgical risk. For example, there is growing experience in transcatheter duct occlusion in symptomatic low-weight or premature infants and stent implantation into the right ventricular outflow tract or arterial duct in cyanotic neonates with duct-dependent pulmonary circulations. The application of percutaneous pulmonary valve implantation has been extended to a broader patient population with dysfunctional ‘native’ right ventricular outflow tracts and has spurred the development of novel techniques and devices to solve associated anatomic challenges. Finally, hybrid strategies, combining cardiosurgical and interventional approaches, have enhanced our capabilities to provide care for those with the most complex of lesions while optimizing efficacy and safety.
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Varol, Rahmetullah, Gokhan Bora Esmer, and Huseyin Uvet. "Interferometric Measurement of TGF-β Induced Epithelial-Mesenchymal Transition of Tumor Cells." Applied Sciences 10, no. 24 (December 20, 2020): 9107. http://dx.doi.org/10.3390/app10249107.

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A three-dimensional profile reconstruction of live cells in dynamic cell cultures is a challenging problem due to the highly scattering nature of cell mediums. Furthermore, it is an interesting problem since these cultures present the optimal in vitro conditions that most closely resemble the cells’ natural conditions. In this paper, we report a holographic method used for imaging during the process of treatment of dynamic cell cultures with transforming growth factor beta (TGF-β) and the subsequent epithelial-mesenchymal transition (EMT). The imaging of dynamic cell cultures presents many challenges for holographic techniques due to the highly scattering and high speed nature of the environment. Here we report the algorithmic workflow we used for decreasing the imaging noise due to the presence of cell medium and achieving high speed reconstruction rates in real time. We also report the prominent morphological features we extracted from the obtained depth maps throughout the experiment. We conducted experiments on four different cell lines: ONCO-DG1, HCT-116, MDA-MB-231, and HUVEC. We observed the EMT process throughout a 48 h period after treatment with TGF-β with 6 h intervals for each sample. We show some examples of the reconstructed depth maps of tumor cells during the EMT phase. From these depth maps we extract some morphological parameters and report how they change after the EMT process is completed. The obtained results indicate that the proposed method presents certain advantages from an optical perspective particularly for applications where a dynamical medium is present. These advantages are lower signal-to-noise ratio (SNR) values and a simple setup compared to the setups used in similar studies. Future studies on this application could lead to the development of a model for the EMT process and its effects on cell to cell interactions.
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Chaban, Antonina, Vivi Tornari, Rita Deiana, Michalis Andrianakis, David Giovannacci, and Vincent Detalle. "A Combined Non-Invasive Approach to the Study of A Mosaic Model: First Laboratory Experimental Results." Journal of Imaging 5, no. 6 (June 10, 2019): 58. http://dx.doi.org/10.3390/jimaging5060058.

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This paper presents first laboratory results of a combined approach carried out by the use of three different portable non-invasive electromagnetic methods: Digital holographic speckle pattern interferometry (DHSPI), stimulated infrared thermography (SIRT) and holographic subsurface radar (HSR), proposed for the analysis of a custom-built wall mosaic model. The model reproduces a series of defects (e.g., cracks, voids, detachments), simulating common deteriorated, restored or reshuffled areas in wall mosaics. DHSPI and SIRT, already well known in the field of non-destructive (NDT) methods, are full-field contactless techniques, providing complementary information on the subsurface hidden discontinuities. The use of DHSPI, based on optical imaging and interferometry, provides remote control and visualization of surface micro-deformation after induced thermal stress, while the use of SIRT allows visualization of thermal energy diffusion in the surface upon the induced thermal stress. DHSPI and SIRT data are complemented by the use of HSR, a contact method that provides localized information about the distribution of contrasts in dielectric permittivity and related possible anomalies. The experimental results, made by the combined use of these methods to the identification of the known anomalies in the mosaic model, are presented and discussed here as a contribution in the development of an efficient non-invasive approach to the in-situ subsurface analysis of ancient wall mosaics.
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45

Gao, Yuan, Ross Harder, Stephen H. Southworth, Jeffrey R. Guest, Xiaojing Huang, Zijie Yan, Leonidas E. Ocola, et al. "Three-dimensional optical trapping and orientation of microparticles for coherent X-ray diffraction imaging." Proceedings of the National Academy of Sciences 116, no. 10 (February 14, 2019): 4018–24. http://dx.doi.org/10.1073/pnas.1720785116.

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Optical trapping has been implemented in many areas of physics and biology as a noncontact sample manipulation technique to study the structure and dynamics of nano- and mesoscale objects. It provides a unique approach for manipulating microscopic objects without inducing undesired changes in structure. Combining optical trapping with hard X-ray microscopy techniques, such as coherent diffraction imaging and crystallography, provides a nonperturbing environment where electronic and structural dynamics of an individual particle in solution can be followed in situ. It was previously shown that optical trapping allows the manipulation of micrometer-sized objects for X-ray fluorescence imaging. However, questions remain over the ability of optical trapping to position objects for X-ray diffraction measurements, which have stringent requirements for angular stability. Our work demonstrates that dynamic holographic optical tweezers are capable of manipulating single micrometer-scale anisotropic particles in a microfluidic environment with the precision and stability required for X-ray Bragg diffraction experiments—thus functioning as an “optical goniometer.” The methodology can be extended to a variety of X-ray experiments and the Bragg coherent diffractive imaging of individual particles in solution, as demonstrated here, will be markedly enhanced with the advent of brighter, coherent X-ray sources.
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46

Van Dyck, D. "What is the Future for Image Simulation?" Microscopy and Microanalysis 3, S2 (August 1997): 1139–40. http://dx.doi.org/10.1017/s1431927600012587.

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The ultimate goal of high resolution electron microscopy is to determine quantitatively the atomic structure of an object. In this respect the electron microscope can be considered as an information channel that carries this information from the object to the observer. High resolution images are then to be considered as data planes from which the structural information has to be extracted.However this structural information is usually hidden in the images and cannot easily be assessed. Therefore, a quantitative approach is required in which all steps in the imaging process are taken into account. Two main approaches have been followed so far in the literature: the indirect approach in which the images are simulated for various plausible trial structures of the object and compared with the experimental images, and the direct approach in which the lost phase information is retrieved using holographic techniques so as to “deblur” the effect of the microscope and to reveal directly the atomic structure of the object.
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47

Lee, Chung-Fei, Wei-Feng Hsu, Tzu-Hsuan Yang, and Ren-Jei Chung. "Three-Dimensional (3D) Printing Implemented by Computer-Generated Holograms for Generation of 3D Layered Images in Optical Near Field." Photonics 8, no. 7 (July 19, 2021): 286. http://dx.doi.org/10.3390/photonics8070286.

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Photocurable three-dimensional (3D) printing is a stepwise layer-by-layer fabrication process widely used in the manufacture of highly specialized objects. Current 3D printing techniques are easily implemented; however, the build rate is slow and the surface quality is less than ideal. Holographic 3D display (3DHD) technology makes it possible to reform planar wavefronts into a 3D intensity distribution, which appears as a 3D image in space. This paper examined the application of holographic imaging technology to 3D printing based on photocurable polymers. The proposed system uses a 3DHD diffractive optics system based on a liquid-crystal-on-silicon spatial light modulator (LCoS-SLM), wherein a 3D layered image is created in the optical near field, based on a computer-generated hologram (CGH) optimized using the iterative angular spectrum algorithm (IASA) and a circular IASA. From a single CGH, multiple 2D sliced images are created in space to form a 3D optical image used to initiate the photopolymerization of photocurable resin to form 3D objects. In experiments, the proposed 3D printing system was used to create five polymer objects with a maximum axial length of 25 mm and minimum feature width of 149 μm. The phase-only CGH reformed the incident light into a distribution of optical intensity with high diffraction efficiency suitable for photocuring. Despite limitations pertaining to fabrication area and axial complexity in this initial study, the proposed method demonstrated high light efficiency, high resolution in the lateral direction, rapid fabrication, and good object continuity.
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48

Horasan, Fahrettin, Muhammed Ali Pala, Ali Durdu, Akif Akgül, Ömer Faruk Akmeşe, and Mustafa Zahid Yıldız. "DWT-SVD Based Watermarking for High-Resolution Medical Holographic Images." Complexity 2022 (August 29, 2022): 1–21. http://dx.doi.org/10.1155/2022/3154650.

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Watermarking is one of the most common techniques used to protect data’s authenticity, integrity, and security. The obfuscation in the frequency domain used in the watermarking method makes the watermarking stronger than the obfuscation in the spatial domain. It occupies an important place in watermarking works in imperceptibility, capacity, and robustness. Finding the optimal location to hide the watermarking is one of the most challenging tasks in these methods and affects the method’s performance. In this article, sample identification information is processed with the method of watermaking on the hiding environment created by using a chaos-based random number generator on biomedical data to provide solutions to problems such as visual attack, identity theft, and information confusion. In order to obtain biomedical data, a lensless digital in-line holographic microscopy (DIHM) setup was designed, and holographic data of human blood and cancer cell lines, which are widely used in the laboratory environment, were obtained. The standard USAF 1951 target was used to evaluate the resolution of our imaging setup. Various QR codes were generated for medical sample identification, and the captured medical data were processed by watermarking it with chaos-based random number generators. A new method using chaos-based discrete wavelet transform (DWT) and singular value decomposition (SVD) has been developed and applied to high-resolution data to eliminate the problem of encrypted data being directly targeted by third-party attacks. The performance of the proposed new watermarking method has been demonstrated by various robustness and invisibility tests. Experimental results showed that the proposed scheme reached an average PSNR value of 564588 dB and SSIM value of 0.9972 against several geometric and destructive attacks, which means that the proposed method does not affect the image quality and also ensures the security of the watermarking information. The results of the proposed method have shown that it can be used efficiently in various fields.
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Treado, Patrick J., Ira W. Levin, and E. Neil Lewis. "High-Fidelity Raman Imaging Spectrometry: A Rapid Method Using an Acousto-Optic Tunable Filter." Applied Spectroscopy 46, no. 8 (August 1992): 1211–16. http://dx.doi.org/10.1366/0003702924123980.

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In this communication, we describe a technique for obtaining high-fidelity Raman images and Raman spectra. The instrumentation provides the ability to rapidly collect large-format images with the number of image pixels limited only by the number of detector elements in the silicon charge-coupled device (CCD). Wavelength selection is achieved with an acousto-optic tunable filter (AOTF), which maintains image fidelity while providing spectral selectivity. Under computer control the AOTF is capable of µs tuning speeds within the operating range of the filter (400–1900 nm). The AOTF is integrated with the CCD and holographic Raman filters to comprise an entirely solid-state Raman imager containing no moving parts. In operation, the AOTF is placed in front of the CCD and tuned over the desired spectral interval. The two-dimensional CCD detector is employed as a true imaging camera, providing a full multichannel advantage over competitive Raman imaging techniques. Images and spectra are presented of a mixture of dipalmitoylphosphatidylcholine (DPPC) and L-asparagine, which serves as a model system for the study of both lipid/peptide and lipid/protein interactions in intact biological materials. The Raman images are collected in only several seconds and indicate the efficacy of this rapid technique for discriminating between multiple components in complex matrices. Additionally, high-quality Raman spectra of the spatially resolved microscopic regions are easily obtained.
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Park, B., M. Silk, D. Kwon, G. Nadolski, S. Hunt, and T. Gade. "03:27 PM Abstract No. 289 Registration of 3D holographic models of patient imaging onto a CT grid: assessment of manual and automatic techniques using HoloLens." Journal of Vascular and Interventional Radiology 30, no. 3 (March 2019): S129. http://dx.doi.org/10.1016/j.jvir.2018.12.354.

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