Transverse Coherence Measurement
Transverse Coherence Measurement - Related Videos
10:39
Measurement of X-ray Beam Coherence along Multiple Directions Using 2-D Checkerboard Phase Grating
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Cited by 10 •
2016
The measurement protocol and data analysis procedure are given for obtaining transverse coherence of a synchrotron radiation X-ray source along four directions simultaneously using a single 2-D checkerboard phase grating. This simple technique can be applied for complete transverse coherence characterization of X-ray sources and X-ray optics.
15:58
Measurement of Coherence Decay in GaMnAs Using Femtosecond Four-wave Mixing
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Cited by 3 •
2013
The technique of femtosecond four-wave mixing is described, including spectrally-resolved and time-resolved configurations. We illustrate the utility of this technique for the investigation of crucial physical properties in the III-V diluted magnetic semiconductors, afforded by its nonlinearity and high temporal resolution.
08:25
Transverse Aortic Constriction in Mice
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Cited by 275 •
2010
Transverse aortic constriction (TAC) in the mouse is a commonly used experimental model to study mechanisms underlying cardiac hypertrophy and heart failure development. Here, we describe procedures to constrict the aorta to create a reproducible degree of cardiac hypertrophy in mice.
07:40
Minimally Invasive Transverse Aortic Constriction in Mice
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Cited by 42 •
2017
Minimally invasive transverse aortic constriction (MTAC) conserves the essentials of regular transverse aortic constriction (TAC) while eliminating the use of a ventilator with tracheal intubation. It proves to be a highly desirable method for high-throughput studies on left ventricular overload, particularly in translational studies.
07:18
Evaluation of Capillary and Other Vessel Contribution to Macular Perfusion Density Measured with Optical Coherence Tomography Angiography
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2022
We describe the evaluation of a coefficient of determination between vessel and perfusion density of the parafoveal superficial capillary plexus to identify the contribution of vessels larger than capillaries to perfusion density.
FAQs
A Young’s double-slit arrangement samples the field at two positions, and the separation between those positions is varied. The resulting fringe visibility, or contrast, indicates how strongly the field remains correlated across that distance. Examining visibility as separation changes therefore reveals the spatial-coherence behavior and supports estimation of the field’s coherence width.
Spatial coherence depends on more than whether the field has similar intensity at two locations. The relevant correlation includes the consistency of both phase and amplitude, which together are represented by the complex degree of spatial coherence. Measuring interference contrast provides information about this combined behavior, helping engineers evaluate how reliably different parts of a field can interfere.
Coherence width describes the characteristic transverse range over which field samples maintain significant spatial correlation. It converts the observed change in interference visibility with separation into a useful beam property. Engineers can use that property when predicting interference performance, assessing beam quality, and understanding how the field may behave as it propagates through an optical system.
The measurement places two sampling points across the field, commonly with a Young’s double-slit arrangement, and observes the resulting interference fringes. The fringe visibility is recorded for different separations between the sampling points. Relating the visibility pattern to separation provides the complex degree of spatial coherence and the associated coherence width.
Visibility data show how interference contrast depends on transverse separation within the field. Stronger persistence of contrast across separation indicates a different spatial-correlation range than a rapid loss of contrast. This information helps characterize the field rather than relying only on its intensity, supporting predictions about beam quality, interference behavior, and propagation.
Engineers apply these measurements to the design and characterization of lasers, imaging systems, optical sensors, and communications links. The resulting spatial-coherence information helps predict system resolution, interference performance, beam quality, and propagation behavior. Its value is that one measurement approach connects field correlations with practical performance in several optical and electromagnetic systems.