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Projection background-oriented schlieren
Applied Optics, 2022A background-oriented schlieren (BOS) system is developed with two benefits over traditional BOS systems. First, the dot pattern required for BOS is projected onto a retroreflective background instead of being painted/printed onto the material itself, allowing for on-the-fly updates to the size and distribution of the dot pattern.
Joshua M. Weisberger, Brett F. Bathel
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Instantaneous 3D flame imaging by background-oriented schlieren tomography
Combustion and Flame, 2018We apply background-oriented schlieren (BOS) imaging with computed tomography to reconstruct the instantaneous refractive index field of a turbulent flame in 3D. In BOS tomography, a network of cameras are focused through a variable index medium (such as
S. J. Grauer +5 more
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Schlieren unwrapped: distortion correction in digital focusing schlieren
Applied Optical Metrology III, 2019Digital focusing schlieren relies on accurate mapping between a camera and a digital modulator or display system. Our early development of the technology was challenged by higher-order distortions in the optical systems. A simple perspective transform was adequate for lower-power lenses and smaller fields of view, but for wide fields and for highly ...
Benjamin D. Buckner, Drew L'Esperance
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Quantitative schlieren visualization
Applied Optics, 1977Using a closed circuit television camera (CCTV), a method was developed to directly obtain quantitative sound pressure measurements from the sound fields imaged in a Schlieren system. By using the exact timed format of the composite video signal and a series of time delay circuits, it was possible to take vertical intensity scans of a Schlieren image ...
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Quantitative Fourier analysis of schlieren masks: the transition from shadowgraph to schlieren
Applied Optics, 2011In a schlieren setup, a lens system forms an image of the refractive index fluctuations of a transparent sample onto a matrix detector while an intensity mask is positioned in the Fourier plane of a collecting lens to perform the required spatial filtering. In the absence of the mask, the resulting technique is that of a shadowgraph.
Croccolo, F, Brogioli, D
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Computer-simulated schlieren optics
Applied Optics, 1985Computer-simulated schlieren pictures are used to interpret and quantitatively analyze schlieren pictures taken from a fast varying plasma with axial symmetry. Structurized angular distributions of deflected rays are obtained from a ray tracing simulation, the characteristics of which are related to density, density gradients, and dimensions of the ...
G, Decker +3 more
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Schlieren effect in Amici prisms
Applied Optics, 1990It is shown that a system consisting of a polarizer, an Amici prism, and an analyzer may act like a phase and amplitude spatial filter capable of producing four fully distinct images. Two of these are complementary Schlieren or Foucault testlike images, another one is like a phase-edge test pattern, and the fourth is similar to a bright field image. An
G, Rodríguez-Zurita +2 more
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