Toward High-Speed 3D Imaging with Phase-Shifting Methods

2018 ◽  
pp. 175-198
Keyword(s):  
High Speed ◽  
3D Imaging ◽  
Phase Shifting

High-speed 3D imaging by parallel phase-shifting digital holography

2015 ◽  
Author(s):  
Yasuhiro Awatsuji ◽  
Peng Xia ◽  
Osamu Matoba
Keyword(s):  
High Speed ◽  
Digital Holography ◽  
3D Imaging ◽  
Phase Shifting

scholarly journals A micromirror array with annular partitioning for high-speed random-access axial focusing

2020 ◽  
Vol 9 (1) ◽  
Author(s):  
Nathan Tessema Ersumo ◽  
Cem Yalcin ◽  
Nick Antipa ◽  
Nicolas Pégard ◽  
Laura Waller ◽  
...  
Keyword(s):  
Adaptive Optics ◽  
Visual Information ◽  
High Speed ◽  
Random Access ◽  
General Purpose ◽  
Phase Shifting ◽  
Optical Systems ◽  
Piston Motion ◽  
Refresh Rate ◽  
Circular Symmetry

Abstract Dynamic axial focusing functionality has recently experienced widespread incorporation in microscopy, augmented/virtual reality (AR/VR), adaptive optics and material processing. However, the limitations of existing varifocal tools continue to beset the performance capabilities and operating overhead of the optical systems that mobilize such functionality. The varifocal tools that are the least burdensome to operate (e.g. liquid crystal, elastomeric or optofluidic lenses) suffer from low (≈100 Hz) refresh rates. Conversely, the fastest devices sacrifice either critical capabilities such as their dwelling capacity (e.g. acoustic gradient lenses or monolithic micromechanical mirrors) or low operating overhead (e.g. deformable mirrors). Here, we present a general-purpose random-access axial focusing device that bridges these previously conflicting features of high speed, dwelling capacity and lightweight drive by employing low-rigidity micromirrors that exploit the robustness of defocusing phase profiles. Geometrically, the device consists of an 8.2 mm diameter array of piston-motion and 48-μm-pitch micromirror pixels that provide 2π phase shifting for wavelengths shorter than 1100 nm with 10–90% settling in 64.8 μs (i.e., 15.44 kHz refresh rate). The pixels are electrically partitioned into 32 rings for a driving scheme that enables phase-wrapped operation with circular symmetry and requires <30 V per channel. Optical experiments demonstrated the array’s wide focusing range with a measured ability to target 29 distinct resolvable depth planes. Overall, the features of the proposed array offer the potential for compact, straightforward methods of tackling bottlenecked applications, including high-throughput single-cell targeting in neurobiology and the delivery of dense 3D visual information in AR/VR.

scholarly journals The human sperm beats anisotropically and asymmetrically in 3D

2019 ◽  
Author(s):  
Hermes Gadêlha ◽  
Paul Hernández-Herrera ◽  
Fernando Montoya ◽  
Alberto Darszon ◽  
Gabriel Corkidi
Keyword(s):  
Ion Channels ◽  
Mathematical Analysis ◽  
Molecular Motors ◽  
High Speed ◽  
3D Imaging ◽  
Human Sperm ◽  
Travelling Wave ◽  
Fundamental Question ◽  
Sperm Flagellum ◽  
Straight Line

The canonical beating of the human sperm flagellum is postulated to be symmetric. This is despite the reported asymmetries inherent to the flagellar axonemal structure, from distribution and activation of molecular motors to, even, the localisation of regulatory ion channels. This raises a fundamental question: how symmetric beating is possible within such intrinsically asymmetric flagellar complex? Here, we employ high-speed 3D imaging with mathematical analysis capable of resolving the flagellar movement in 4D (3D+time). This reveals that the human sperm beating is both anisotropic and asymmetric, and composed by a superposition of two transversal waves: an asymmetric travelling wave and a symmetric standing wave. This novel anisotropic travelling-pulsation mechanism induces sperm rolling self-organisation and causes a flagellar kinematic illusion, so that the beat appears to be symmetric if observed with 2D microscopy. The 3D beating anisotropy thus regularises the intrinsic flagellar asymmetry to achieve symmetric side-to-side movement and straight-line swimming.

Phase Algorithm Integrating Direct-Correlation and Four-Step Phase-Shifting for Electronic Speckle Pattern Interferometry

2013 ◽  
Vol 448-453 ◽  
pp. 3696-3701
Author(s):  
Yan Bin He ◽  
Xin Zhong Li ◽  
Min Zhou
Keyword(s):  
High Speed ◽  
Speckle Pattern ◽  
Phase Shifting ◽  
Electronic Speckle Pattern Interferometry ◽  
High Speed Camera ◽  
Dynamic Measurements ◽  
High Quality ◽  
Correlation Algorithm ◽  
Phase Map

A phase-shifting algorithm, called a (4,4) algorithm, which takes four phase-shifting interferograms before a specimen is deformed and four interferograms after a specimen is deformed, is presented first. This method is most widely used for phase extraction. Its drawback limited it to be used in dynamic measurements. Also shown is an algorithm called a (4,1) algorithm that takes four phase-shifting interferograms before a specimen is deformed and one interferogram after a specimen is deformed. Because a high-speed camera can be used to record the dynamic interferogram of the specimen, this algorithm has the potential to retain the phase-shifting capability for ESPI in dynamic measurements. The quality of the phase map obtained using (4,1) algorithm is quite lower compared to using (4,4) algorithm. In order to obtain high-quality phase map in dynamic measurements, a direct-correlation algorithm was integrated with the (4,1) algorithm to form DC-(4,1) algorithm which is shown to improve significantly the quality of the phase maps. The theoretical and experimental aspects of this newly developed technique, which can extend ESPI to areas such as high-speed dynamic measurements, are examined in detail.

Terahertz 3D imaging with a CW source and phase-shifting interferometry

2013 ◽  
Author(s):  
Yoshiaki Sasaki ◽  
Chiko Otani ◽  
Hiroshi Kasuga ◽  
Hitoshi Ohmori ◽  
Masayuki Suga ◽  
...  
Keyword(s):  
3D Imaging ◽  
Phase Shifting ◽  
Phase Shifting Interferometry

Phase-shifting algorithm to achieve high-speed long-depth-range probing by frequency-domain optical coherence tomography

2003 ◽  
Vol 28 (22) ◽  
pp. 2201 ◽  
Author(s):  
Rainer A. Leitgeb ◽  
Christoph K. Hitzenberger ◽  
Adolf F. Fercher ◽  
Tomasz Bajraszewski
Keyword(s):  
Optical Coherence Tomography ◽  
Frequency Domain ◽  
High Speed ◽  
Phase Shifting ◽  
Depth Range ◽  
Optical Coherence
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