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Wavefront sensing and control software for a segmented space telescope
This paper describes the engineering version of the STCS, the algorithms it incorporates, and methods of communicating with the testbed hardware.
Real-time wavefront processors for the next generation of adaptive optics systems: a design and analysis
This paper characterizes the performance of a single deformable mirror Shack-Hartmann natural guide star AO system based on the present-generation digital signal processors TMS320C6701 from Texas Instruments.
Wavefront Control for a Segmented Deployable Space Telescope
By segmenting and folding the primary mirror, quite large telescopes can be packed into the nose cone of a rocket.
Wavefront Sensing and Control for a Next Generation Space Telescope
The Next Generation Space Telescope will provide more than ten times the collecting area of the Hubble Space Telescope in a package that fits into the shroud of an expendable launch vehicle. This paper illustrates the operation and performance expected for initial telescope alignment, segment phasing, and fine figure control for the NGST yardstick design.
Optimizing fluorescence imaging through scattering media using structured light-assisted wavefront shaping
Not provided.
Electrically Tunable Topological Singularities in Excitonic Two-Dimensional Heterostructures for Wavefront Manipulation
Not provided.
The Focal-plane Actualized Shifted Technique Realized for a Shack Hartmann Wavefront Sensor (fastrSHWFS)
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Developing a Wynne Corrector for higher spectral bandwidth focal plane wavefront sensing
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Wavefront error based tilt-to-length noise analysis for the LISA transmitted beam
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Efficient wavefront sensing for space-based adaptive optics
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Interference between wavefronts rotated or reversed with respect to each other and its relation to spatial coherence.
Contrast of interference fringes in twyman-green interferometer determined by spatial coherence of light source
Interferograms of window wavefront deformations as a measure of angular deviations to a line of sight
Interferograms of window wave front deformations to measure angular deviations to line of sight
Uniform wavefront expansions for diffracted and focusing waves
Approximative solutions for diffracted and focusing wave front expansions in sonic boom shock wave propagation
Quantized vortices around wavefront nodes, 2
Quantized vortices can occur around nodal points in wavefunctions. The derivation depends only on the wavefunction being single valued, continuous, and having continuous first derivatives. Since the derivation does not depend upon the dynamical equations, the quantized vortices are expected to occur for many types of waves such as electromagnetic and acoustic. Such vortices have appeared in the calculations of the H + H2 molecular collisions and play a role in the chemical kinetics. In a companion paper, it is shown that quantized vortices occur when optical waves are internally reflected from the face of a prism or particle beams are reflected from potential energy barriers.
Active wavefront correction in large telescopes
Astronomical progress with the MMT telescope, which attains high-resolution imaging by partial compensation for atmospheric distortion, is discussed. The small tertiary and beam combiner mirrors at the MMT bring six images to a common focus, where there is a TV system for acquisition and guiding. Individual image positions can be controlled by stepper motors driving actuators on the secondaries, each step moving an image 0.05 arc seconds in the focal plane. The instrument's correction for image jiggle due to atmospheric turbulence and drift of the relative positions of the images due to gravitational and thermal effects on the structure are described. A scheme for correcting residual structural errors is discussed. It appears that the telescope can work to about the 17th visual magnitude. For faint sky limited objects comparable performance would require a perfectly rigid single mirror of the same aperture to have 50 percent more collecting area and cost at least 1.5 times more.
Compensation for Primary Reflector Wavefront Error
The object of the invention is to compensate for errors in a large telescope primary reflector by making certain compensating deviations in a smaller, auxiliary reflector of the telescope. At least one intermediate element forms an image of the primary surface onto the secondary surface, so each point on the secondary surface corresponds to a point on the primary surface. The secondary surface is formed with a deviation from an ideal secondary surface, with the piston distance of each point on the actual secondary surface equal to the piston distance of a corresponding piston on the actual primary surface from the ideal primary surface. It is found that this results in electromagnetic (e.g., light) rays which strike a deviating area of the actual primary surface being brought to the same focus as if the actual primary surface did not have a diviation from an ideal primary surface.