Read by QxMD icon Read


Hidehito Adaniya, Martin Cheung, Cathal Cassidy, Masao Yamashita, Tsumoru Shintake
A new SEM-based in-line electron holography microscope has been under development. The microscope utilizes conventional SEM and BF-STEM functionality to allow for rapid searching of the specimen of interest, seamless interchange between SEM, BF-STEM and holographic imaging modes, and makes use of coherent low-energy in-line electron holography to obtain low-dose, high-contrast images of light element materials. We report here an overview of the instrumentation and first experimental results on gold nano-particles and carbon nano-fibers for system performance tests...
March 6, 2018: Ultramicroscopy
Karl Landsteiner, Esperanza Lopez, Guillermo Milans Del Bosch
In the presence of a gravitational contribution to the chiral anomaly, the chiral magnetic effect induces an energy current proportional to the square of the temperature in equilibrium. In holography the thermal state corresponds to a black hole. We numerically study holographic quenches in which a planar shell of scalar matter falls into a black hole and raises its temperature. During the process the momentum density (energy current) is conserved. The energy current has two components, a nondissipative one induced by the anomaly and a dissipative flow component...
February 16, 2018: Physical Review Letters
Jian Su, Xingpeng Yan, Xiaoyu Jiang, Yingqing Huang, Yibei Chen, Teng Zhang
Based on our proposed method for holographic stereogram printing using effective perspective images' segmentation and mosaicking (EPISM), we analyze the reconstructed wavefront errors, and establish the exit pupil function model of proposed printing system. To evaluate the imaging quality, the optical transfer function (OTF) of the holographic stereogram is modelled from the aspect of frequency response. The characteristic of the OTF with respect to the exit pupil size and the aberration are investigated in detail...
March 14, 2018: Scientific Reports
Angelo Forli, Dania Vecchia, Noemi Binini, Francesca Succol, Serena Bovetti, Claudio Moretti, Francesco Nespoli, Mathias Mahn, Christopher A Baker, McLean M Bolton, Ofer Yizhar, Tommaso Fellin
Sensory information is encoded within the brain in distributed spatiotemporal patterns of neuronal activity. Understanding how these patterns influence behavior requires a method to measure and to bidirectionally perturb with high spatial resolution the activity of the multiple neuronal cell types engaged in sensory processing. Here, we combined two-photon holography to stimulate neurons expressing blue light-sensitive opsins (ChR2 and GtACR2) with two-photon imaging of the red-shifted indicator jRCaMP1a in the mouse neocortex in vivo...
March 13, 2018: Cell Reports
M Sanz, J A Picazo-Bueno, J García, V Micó
We report on a novel layout capable of dual-mode imaging in real time with different magnifications and resolution capabilities in lensless microscopy. The concept is based on wavelength multiplexing for providing two illuminations with different wavefront curvatures: one is collimated, allowing a large field of view (FOV) with a poor resolution limit, and the other is divergent, to achieve a better resolution limit (micron range) over a small FOV. Moreover, our recently reported concept of MISHELF microscopy [M...
March 13, 2018: Lab on a Chip
Kuang Zhang, Hao Yu, Xumin Ding, Qun Wu
In this paper, a holographic metasurface possessing beam scanning capability at fixed frequency is presented. The desired radiation beam is obtained by using a reference wave to excite a sinusoidally-modulated impedance surface, which is equivalent to the interference pattern between the radiation wave and reference wave. By changing the bias voltage of varactor diodes loaded on the sub-wavelength unit cells, the variation range of the modulated impedance can be tuned, resulting in the change of radiation angle...
March 5, 2018: Optics Express
Kang-Han Kim, Yong-Cheol Jeong
We present one-step method of fabricating hierarchical multiscale grating patterns by using holographic lithography on azobenzene thin films. In this study, we investigate the growth behavior of surface relief gratings in terms of surface morphology change regarding various optical conditions of different fringe visibility, exposure dose and polarization modes of the light interference pattern. The results reveal that different-sized diffractive gratings could be fabricated orthogonally at the same time. We also explain that these orthogonal gratings were developed through the different light-induced deformation mechanism...
March 5, 2018: Optics Express
Jani Mäkinen, Erdem Sahin, Atanas Gotchev
We propose a speckle noise reduction method for generation of coherent holographic stereograms. The method employs densely sampled light field (DSLF) of the scene together with depth information acquired for each ray in the captured DSLF. Speckle reduction is achieved based on the ray separation technique where the scene is first described as a superposition of sparse sets of point sources corresponding to separated sets of rays and then the holographic reconstructions corresponding to these sparse sets of point sources are added incoherently (intensity-wise) to obtain the final reconstruction...
March 5, 2018: Optics Express
Okan Yurduseven, Daniel L Marks, Thomas Fromenteze, David R Smith
We present a reconfigurable, dynamic beam steering holographic metasurface aperture to synthesize a microwave camera at K-band frequencies. The aperture consists of a 1D printed microstrip transmission line with the front surface patterned into an array of slot-shaped subwavelength metamaterial elements (or meta-elements) dynamically tuned between "ON" and "OFF" states using PIN diodes. The proposed aperture synthesizes a desired radiation pattern by converting the waveguide-mode to a free space radiation by means of a binary modulation scheme...
March 5, 2018: Optics Express
Muhammed Veli, Aydogan Ozcan
We present a cost-effective and portable platform based on contact lenses for non-invasively detecting Staphylococcus aureus, which is part of the human ocular microbiome and resides on the cornea and conjunctiva. Using Staphylococcus aureus-specific antibodies and a surface chemistry protocol that is compatible with human tear, contact lenses are designed to specifically capture Staphylococcus aureus. After the bacteria capture on the lens, and right before its imaging, the captured bacteria are tagged with surface-functionalized polystyrene microparticles...
March 9, 2018: ACS Nano
Xianfeng Xu, Zhiwei Zhang, Zecheng Wang, Jing Wang, Kaiyun Zhan, Yulei Jia, Zhiyong Jiao
A robust digital holography recording design is presented to complete the work of switching between in-line and off-axis recording methods. We precisely supervise the off-axis angle in off-axis holography, so that the original reconstructed image can be separated by a minimum off-axis angle. In the design, we can also monitor and remove the negative effects of the reference tilt error in phase-shifting digital holography. Compared with the conventional digital holographic recording configuration, a supervising unit is introduced to control and to monitor the angle between the reference beam and object beam...
March 1, 2018: Applied Optics
Timothy O'Connor, Siddharth Rawat, Adam Markman, Bahram Javidi
We propose a compact imaging system that integrates an augmented reality head mounted device with digital holographic microscopy for automated cell identification and visualization. A shearing interferometer is used to produce holograms of biological cells, which are recorded using customized smart glasses containing an external camera. After image acquisition, segmentation is performed to isolate regions of interest containing biological cells in the field-of-view, followed by digital reconstruction of the cells, which is used to generate a three-dimensional (3D) pseudocolor optical path length profile...
March 1, 2018: Applied Optics
Mohammad A Charsooghi, Ali-Reza Moradi
In this paper, we measure the proximity effect of a flat wall on the sedimentation of colloidal particles by the use of digital holographic microscopy (DHM). DHM provides quantitative phase contrast and three-dimensional (3D) imaging in arbitrary time scales that are suitable to investigate various phenomena, including dynamic behavior of colloids. 3D information is obtained by post-processing of the recorded digital holograms through the angular spectrum propagation approach for numerical reconstruction. We have measured the trajectory and velocity of spherical colloids in various distances from a flat wall while they sediment under gravity...
March 1, 2018: Applied Optics
Jagadesh Ramaiah, Pramod Rastogi, Gannavarpu Rajshekhar
This paper presents a method for extracting multiple phases from a single moire fringe pattern in digital holographic interferometry. The method relies on component separation using singular value decomposition and an extended Kalman filter for demodulating the moire fringes. The Kalman filter is applied by modeling the interference field locally as a multi-component polynomial phase signal and extracting the associated multiple polynomial coefficients using the state space approach. In addition to phase, the corresponding multiple phase derivatives can be simultaneously extracted using the proposed method...
March 10, 2018: Applied Optics
N A Davidenko, I I Davidenko, V A Pavlov, N G Chuprina, V V Kravchenko, N N Kuranda, E V Mokrinskaya, S L Studzinsky
The photothermoplastic medium based on the films of photosensitive polymeric composites with semiconductor properties is developed for application in optical information recording and storage, in holographic interferometry, as well as for medical purposes. This medium was used in the modified holographic device for determination of changes of the refractive index of homogeneous and inhomogeneous liquid objects. The technique and holographic equipment were modified by employing the specially developed and produced transparent cuvette of special shape and the phase shifting interferometry method...
March 10, 2018: Applied Optics
H Matsuura, Y Nagasaka
We describe an instrument for the measurement of the Soret and thermodiffusion coefficients in ternary systems based on the transient holographic grating technique, which is called Soret forced Rayleigh scattering (SFRS) or thermal diffusion forced Rayleigh scattering (TDFRS). We integrated the SFRS technique and the two-wavelength detection technique, which enabled us to obtain two different signals to determine the two independent Soret coefficients and thermodiffusion coefficients in ternary systems. The instrument has been designed to read the mass transport simultaneously by two-wavelength lasers with wavelengths of λ = 403 nm and λ = 639 nm...
February 2018: Review of Scientific Instruments
Ruiya Ji, Shencheng Fu, Xintong Zhang, Xiuxiu Han, Shuangyan Liu, Xiuli Wang, Yichun Liu
Stability and integration are the goals for developing photonic devices. Spirooxazines have the property of photoinduced merocyanine-aggregation in polymer matrix, which can be applied to fluorescence emission and stable information storage. Although visible light coherent radiation with UV-assist has been used to achieve polarization-modulated holographic memory in spirooxazine doped PMMA films, the complexity of optical systems is increased and the aggregation ability of merocyanine is decreased. Here, we report that fluorescent holographic gratings with a surface relief structure can be inscribed in the film via sole irradiation of 403...
February 28, 2018: Scientific Reports
Xin-Ji Lai, Han-Yen Tu, Yu-Chih Lin, Chau-Jern Cheng
This paper proposes a coded aperture structured illumination (CASI) technique in digital holographic microscopy (DHM). A CASI wave is generated using two binary phase codes (0° and 120°) for spatial phase shifting. The generated CASI wave then interferes with a reference wave to form a coded Fresnel hologram at a single exposure with compressive sensing (CS) to avoid the temporal phase-shifting process of the structured illumination (SI). The CS algorithm is applied to retrieve the missing data of decoded phase-shifted SI-modulated waves, which are used to separate overlapped spatial frequencies for obtaining a larger spatial frequency coverage to provide superresolution imaging...
March 1, 2018: Optics Letters
José Ángel Picazo-Bueno, Maciej Trusiak, Javier García, Krzysztof Patorski, Vicente Micó
Hilbert-Huang single-shot spatially multiplexed interferometric microscopy (H2S2MIM) is presented as the implementation of a robust, fast, and accurate single-shot phase estimation algorithm with an extremely simple, low-cost, and highly stable way to convert a bright field microscope into a holographic one using partially coherent illumination. Altogether, H2S2MIM adds high-speed (video frame rate) quantitative phase imaging capability to a commercially available nonholographic microscope with improved phase reconstruction (coherence noise reduction)...
March 1, 2018: Optics Letters
Jinpeng Liu, Hideyoshi Horimai, Xiao Lin, Yong Huang, Xiaodi Tan
A novel phase modulation method for holographic data storage with phase-retrieval reference beam locking is proposed and incorporated into an amplitude-encoding collinear holographic storage system. Unlike the conventional phase retrieval method, the proposed method locks the data page and the corresponding phase-retrieval interference beam together at the same location with a sequential recording process, which eliminates piezoelectric elements, phase shift arrays and extra interference beams, making the system more compact and phase retrieval easier...
February 19, 2018: Optics Express
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"