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Optical vortex coronagraphs

Frontiers in Optics 2004/Laser Science XXII/Diffractive Optics and Micro-Optics/Optical Fabrication and Testing, 2004
Starlight transmitted through an optical vortex was observed to form a dark core in the image of the star despite atmospheric turbulence. This affords opportunities to use optical vortices in the hunt for extrasolar planets and zodiacal dust. Observations using a 60-inch f/16 telescope will be reported.
Grover Swartzlander   +5 more
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Transversal optical vortex

Optics Communications, 2001
Abstract A structure of wavefront edge dislocations and associated “transversal” optical vortices in an interference field of two two-dimensional Gaussian beams is analyzed. It was shown that the optical vortex rotation is directed toward the area of higher phase velocity in the interference field (the origin of the phase velocity variation is due to
V.A Pas'ko, M.S Soskin, M.V Vasnetsov
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Optical vortex manipulation

Frontiers in Optics, 2003
Optical vortices can provide mechanisms for micromanipulation of micron or sub-micron sized particles as well as a means to generate complicated array patterns. Particularly interesting is the way in which higher order vortices can be triggered by a secondary optical field to explode or implode.
Michael A. Fiddy   +1 more
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Optical Rankine Vortex

Frontiers in Optics, 2005
An optical vortex may exhibit a hallmark attributed to viscosity in classical fluids: solid-body rotation near the vortex core. This effect, attributed to spatial coherence properties, may be extended beyond optics to other wave systems. Non-quantized circulation results.
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Optical Vortex Coronagraph

Frontiers in Optics 2007/Laser Science XXIII/Organic Materials and Devices for Displays and Energy Conversion, 2007
The optical vortex coronagraph is a promising scheme for achieving high contrast low loss imaging of exoplanets. Observatory and laboratory measurements will be presented and analyzed. Procedures for achieving improved performance will be described.
Grover A. Swartzlander   +7 more
openaire   +1 more source

The optical vortex coronagraph

Journal of Optics A: Pure and Applied Optics, 2009
An optical vortex coronagraph is a high contrast imaging system which has the potential to completely extinguish light from an on-axis point source, allowing glare-free, high throughput imaging of off-axis targets. An important application is the direct detection of exoplanets orbiting distant stars.
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Optical vortex trajectories

Optics Communications, 2000
Specific rules are formulated that constrain relationships between optical vortex trajectories on a given manifold. Possible topologies for these trajectories are considered.
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An optical vortex coronagraph

SPIE Proceedings, 2005
An optical vortex may be characterized as a dark core of destructive interference in a beam of spatially coherent light. This dark core may be used as a filter to attenuate a coherent beam of light so an incoherent background signal may be detected. Applications of such a filter include: eye and sensor protection, forward-scattered light measurement ...
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The Restless Optical Vortex

1993
We describe a phenomenon of nonlinear optics that occurs in the framework of transverse effects and optical vortices in lasers. We find that in a class-B laser vortices can never be at rest, but move, starting from an initial symmetry breaking of the direction of motion, continuously.
C. O. Weiss   +3 more
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The Optical Vortex Lens

Optics and Photonics News, 2006
A helical-shaped phase mask can be used as a type of "optical vortex lens" that may lead to improvements in astronomical observation, the manipulation of micro-particles, optical pattern recognition and other areas.
openaire   +1 more source

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