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Donghan Ma, Yuxuan Zhao, Lijiang Zeng
Large-area holographic gratings are of great importance in diverse fields including long-range interference metrology, high-resolution astronomical telescopes, and chirped-pulse-amplification systems. However, in conventional interference lithography, the recording length is limited by the aperture of the collimating lenses. Here we propose broad-beam scanning exposure which employs the latent grating generated continuously during scanning for real-time dynamic fringe locking and thus achieves unlimited recording length...
April 19, 2017: Scientific Reports
Jiwei Zhang, Siqing Dai, Chaojie Ma, Jianglei Di, Jianlin Zhao
We develop a common-path digital holographic microscopy based on prism-coupling surface plasmon resonance (SPR) for near-field phase imaging. A single beam splitter with specific configuration is introduced in an SPR imaging system to realize off-axis holographic recording. By measuring the phase shift difference of the reflected light at SPR exploiting the proposed holographic microscopy with high temporal stability, near-field characteristic measurement can be realized. With its simplicity, vibration isolation, and inherent capability of phase curvature compensation, the recommended system shows advanced performance in monitoring tiny refractive index variations and imaging biological tissues...
April 10, 2017: Applied Optics
Alejandro V Arzola, Mario Villasante-Barahona, Karen Volke-Sepúlveda, Petr Jákl, Pavel Zemánek
A fully reconfigurable two-dimensional (2D) rocking ratchet system created with holographic optical micromanipulation is presented. We can generate optical potentials with the geometry of any Bravais lattice in 2D and introduce a spatial asymmetry with arbitrary orientation. Nontrivial directed transport of Brownian particles along different directions is demonstrated numerically and experimentally, including on axis, perpendicular, and oblique with respect to an unbiased ac driving. The most important aspect to define the current direction is shown to be the asymmetry and not the driving orientation, and yet we show a system in which the asymmetry orientation of each potential well does not coincide with the transport direction, suggesting an additional symmetry breaking as a result of a coupling with the lattice configuration...
March 31, 2017: Physical Review Letters
Basanth S Kalanoor, Maria Ronen, Ziv Oren, Doron Gerber, Yaakov R Tischler
The low-frequency vibrational (LFV) modes of biomolecules reflect specific intramolecular and intermolecular thermally induced fluctuations that are driven by external perturbations, such as ligand binding, protein interaction, electron transfer, and enzymatic activity. Large efforts have been invested over the years to develop methods to access the LFV modes due to their importance in the studies of the mechanisms and biological functions of biomolecules. Here, we present a method to measure the LFV modes of biomolecules based on Raman spectroscopy that combines volume holographic filters with a single-stage spectrometer, to obtain high signal-to-noise-ratio spectra in short acquisition times...
March 31, 2017: ACS Omega
Johannes Hagemann, Tim Salditt
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...
April 1, 2017: Journal of Applied Crystallography
Chenliang Chang, Yijun Qi, Jun Wu, Jun Xia, Shouping Nie
This paper presents a method for the implementation of speckle reduced lensless holographic projection based on phase-only computer-generated hologram (CGH). The CGH is calculated from the image by double-step Fresnel diffraction. A virtual convergence light is imposed to the image to ensure the focusing of its wavefront to the virtual plane, which is established between the image and the hologram plane. The speckle noise is reduced due to the reconstruction of the complex amplitude of the image via a lensless optical filtering system...
March 20, 2017: Optics Express
Byung-Mok Kim, Seong-Jin Park, Eun-Soo Kim
Single-shot digital holographic microscopy (SS-DHM) with a modified lateral-shearing interferometer (MLSI) based on computational telecentricity is proposed. The proposed system is composed of three-step processes such as optical recording, digital compensation and numerical reconstruction processes. In the 1st step, the object beam is optically recorded with the MLSI, where a tube lens is set to be located at the slightly shorter distance than its focal length from the objective lens. Then, another phase factor due to the deviated locating of the tube lens from its focal length is additionally generated, which is called an additional quadratic phase factor (AQPF)...
March 20, 2017: Optics Express
Qiankun Gao, Juan Liu, Xinhui Duan, Tao Zhao, Xin Li, Peilin Liu
A compact see-through three-dimensional head-mounted display (3D-HMD) is proposed and investigated in this paper. Two phase holograms are analytically extracted from the object wavefront and uploaded on different zones of the spatial light modulator (SLM). A holographic grating is further used as the frequency filter to couple the separated holograms together for wavefront modulation. The developed preliminary prototype has a simple optical facility and a compact structure (133.8mm × 40.4mm × 35.4mm with a 47...
April 3, 2017: Optics Express
Sixing Xi, Xiaolei Wang, Lipei Song, Zhuqing Zhu, Bowen Zhu, Shuai Huang, Nana Yu, Huaying Wang
Optical image encryption, especially double-random-phase-based, is of great interest in information security. In this work, we experimentally demonstrate the security and feasibility of optical image encryption with asymmetric double random phase and computer-generated hologram (CGH) by using spatial light modulator. First of all, the encrypted image modulated by asymmetric double random phase is numerically encoded into real-value CGH. Then, the encoded real-value CGH is loaded on the spatial light modulator and optically decrypted in self-designed experimental system...
April 3, 2017: Optics Express
Xuan Liu, Yang Yang, Lu Han, Cheng-Shan Guo
We report a fiber-based lensless holographic imaging system to realize a single-shot measurement of two dimensional (2-D) Jones matrix parameters of polarization-sensitive materials. In this system, a multi-source lensless off-axis Fresnel holographic recording geometry is adopted, and two optical fiber splitters are used to generate the multiple reference and illumination beams required for recording a four-channel angular-multiplexing polarization hologram (AMPH). Using this system and the method described in this paper, spatially resolved Jones matrix parameters of a polarization-sensitive material can be retrieved from one single-shot AMPH...
April 3, 2017: Optics Express
Sergei Sokolov, Jin Lian, Emre Yüce, Sylvain Combrié, Alfredo De Rossi, Allard P Mosk
Weakly coupled high-Q nanophotonic cavities are building blocks of slow-light waveguides and other nanophotonic devices. Their functionality critically depends on tuning as resonance frequencies should stay within the bandwidth of the device. Unavoidable disorder leads to random frequency shifts which cause localization of the light in single cavities. We present a new method to finely tune individual resonances of light in a system of coupled nanocavities. We use holographic laser-induced heating and address thermal crosstalk between nanocavities using a response matrix approach...
March 6, 2017: Optics Express
Jian-Hai Yu, Xu-Ling Liu, Yu-Jing Liu, Xiao-En He, Yuan Hui, Bao Zhang, Li Zhu, Wei Zhao
OBJECTIVE: To monitor the 3-dimensional (3D) morphological changes of C6/36 cells during dengue virus (DENV) infection using a live-cell imaging technique based on digital holographic microscopy and provide clues for better understanding the mechanisms of DENV infection. METHODS: C6/36 cells were seeded in 6-well plates to determine the optimal imaging density under a holographic cell imager, and the morphological changes of the cells were recorded in response to a culture temperature change from 28 degrees celsius; to 37 degrees celsius; C6/36 cells were infected with 4 DENV strains with different serotypes at 28 degrees celsius; and incubated at 37 degrees celsius; for 24 h, and the 3D holograms and relevant morphological parameters were recorded at different time points using HoloMonitor M4 holographic cell imaging and analysis system...
March 20, 2017: Nan Fang Yi Ke da Xue Xue Bao, Journal of Southern Medical University
Young-Ho Seo, Yoon-Hyuk Lee, Dong-Wook Kim
In this paper, we propose a new hardware architecture implemented as a very large scaled integrated circuit by using an application-specific integrated circuit technology, where block-based calculations are used to generate holograms. The proposed hardware is structured to produce a part of a hologram in the block units in parallel. A block of a hologram is calculated using an object point, and then the calculation is repeated for all object points to obtain intermediate results that are accumulated to produce the final block of a hologram...
March 20, 2017: Applied Optics
Mostafa Aakhte, Vahid Abbasian, Ehsan Ahadi Akhlaghi, Ali-Reza Moradi, Arun Anand, Bahram Javidi
In this paper, we use a glass microsphere incorporated into a digital holographic microscope to increase the effective resolution of the system, aiming at precise cell identification. A Mirau interferometric objective is employed in the experiments, which can be used for a common-path digital holographic microscopy (DHMicroscopy) arrangement. High-magnification Mirau objectives are expensive and suffer from low working distances, yet the commonly used low-magnification Mirau objectives do not have high lateral resolutions...
March 20, 2017: Applied Optics
Siddharth Rawat, Satoru Komatsu, Adam Markman, Arun Anand, Bahram Javidi
We propose a low-cost, compact, and field-portable 3D printed holographic microscope for automated cell identification based on a common path shearing interferometer setup. Once a hologram is captured from the portable setup, a 3D reconstructed height profile of the cell is created. We extract several morphological cell features from the reconstructed 3D height profiles, including mean physical cell thickness, coefficient of variation, optical volume (OV) of the cell, projected area of the cell (PA), ratio of PA to OV, cell thickness kurtosis, cell thickness skewness, and the dry mass of the cell for identification using the random forest (RF) classifier...
March 20, 2017: Applied Optics
Brandon Redding, Allen Davis
We investigate the ability of a holographic laser vibrometer to mitigate noise introduced when operating on a moving platform or when measuring a moving target. This motion introduces a fundamental limitation on the measurement sensitivity due to the time-varying speckle pattern produced as the illumination beam scans across the target surface. In addition, since existing systems record the phase of only a single speckle grain, speckle fading imposes a limit on the coherent processing interval and thus the frequency resolution of these measurements...
March 20, 2017: Applied Optics
Sergei G Krivoshlykov
Holographic recording of the relief-free volume phase Fresnel lenses in polycrystalline ZnSe semiconductor material, which is transparent from the visible to long-wave infrared wavelengths, is demonstrated. The room-temperature process of photomodification, which changes the refractive index of the semiconductor material dramatically (Δn=0.74-1.2) under illumination with low-intensity light, is used for recording the Fresnel lens employing a computer-generated photomask in the proximity configuration. The thin-plate volume phase diffractive optics offers broader functionality and at least three-fold cost reduction due to the saving of expensive material and labor...
March 10, 2017: Applied Optics
Teli Xi, Jianglei Di, Xiaofeng Guan, Ying Li, Chaojie Ma, Jiwei Zhang, Jianlin Zhao
Phase-shifting infrared digital holographic microscopy based on a homemade all-fiber variable phase shifter is presented to quantitatively obtain the phase distribution of an object wave carrying the information of a transparent specimen in the infrared band. The all-fiber variable phase shifter, which consists of a tubular piezoelectric transducer (PZT) and a single-mode fiber, can accurately produce any phase shift between 0 and 2π by modulating the driving voltage of the tubular PZT. Taking measurements of different staircase structures on a silicon wafer as samples, two configurations are presented based on different phase-shifting implementations: one is a slight off-axis two-step phase shift and the other is an in-line four-step phase shift...
April 1, 2017: Applied Optics
Ed Luther, Livia P Mendes, Jiyai Pan, Daniel F Costa, Vladimir P Torchilin
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 CO2 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...
March 30, 2017: Cytometry. Part A: the Journal of the International Society for Analytical Cytology
Kamran Qaderi, Christopher Leach, Daniel E Smalley
In this Letter, we present a paired set of waveguide spatial light modulators (SLMs) capable of a maximum light deflection nearing 28° for red. This deflection, which is several times larger than the angular sweep of current, state-of-the-art modulators, is made possible by the unilateral, near-collinear waveguide nature of the leaky mode interaction. The ability to double angular output in this way, which is either not possible or not practical in other SLMs, is possible in leaky mode devices, thanks to the absence of zero-order light and the lack of high-order outputs...
April 1, 2017: Optics Letters
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