Results 71 to 80 of about 70,563 (294)

Investigation into the Co-Phase Detection Methodology for Segmented Plane Mirrors Utilizing Grazing Incidence Interferometry

Sensors
Segmented plane mirrors constitute a crucial component in the self-aligned detection process for large-aperture space optical imaging systems. Surface shape errors inherent in segmented plane mirrors primarily manifest as tilt errors and piston errors ...
Rengcong Liu, Jiang Guo, Yibo Li
doaj   +1 more source

Analytical expressions for optimum alignment modes of highly segmented mirrors

, 2004
The major sources causing deterioration of optical quality in extremely large optical telescopes are misadjustments of the mirrors, deformations of monolithic mirrors, and misalignments of segments in segmented mirrors. For active optics corrections, all
Cantrill CD, L. Noethe, Troy M
core   +1 more source

Tribological Performance of 60NiTi Alloy Under Varying Contact Conditions and Elevated Temperatures in Linear Reciprocating Sliding

Advanced Engineering Materials, EarlyView.
This study investigates the tribological response of 60NiTi alloy under dry, water‐lubricated and high‐temperature conditions. The alloy exhibits decreasing wear volume and friction with increasing temperature due to the formation of protective oxide layers. The work clarifies dominant wear mechanisms and demonstrates the suitability of 60NiTi for high‐
Anthony Onyebuchi Okoani, Miguel Angel Selles, Maziar Ramezani   +2 more
wiley   +1 more source

ROBAST: Development of a ROOT-Based Ray-Tracing Library for Cosmic-Ray Telescopes and its Applications in the Cherenkov Telescope Array

, 2015
We have developed a non-sequential ray-tracing simulation library, ROOT-based simulator for ray tracing (ROBAST), which is aimed to be widely used in optical simulations of cosmic-ray (CR) and gamma-ray telescopes.
Noda, Koji, Okumura, Akira, Rulten, Cameron   +2 more
core   +1 more source

Affecting the Properties of Copper–Graphene Electroconductive Composite by Severe Plastic Deformation

Advanced Engineering Materials, EarlyView.
Copper‐based composites enhanced with carbon feature convenient mechanical properties and favorable electric conductivity. Processing via deformation and thermomechanical treatments can introduce advantageous microstructures further enhancing their performance. Herein, copper–graphene powder‐based composites are directly consolidated via rotary swaging
Radim Kocich, Lenka Kunčická, Pavel Czernek, Zifan Wang   +3 more
wiley   +1 more source

Large Range of a High-Precision, Independent, Sub-Mirror Three-Dimensional Co-Phase Error Sensing and Correction Method via a Mask and Population Algorithm

Sensors
The emergence of segmented mirrors is expected to solve the design, processing, manufacturing, testing, and launching of space telescopes of large apertures.
Dequan Li, Dong Wang, Jingquan Li
doaj   +1 more source

Method and apparatus for phasing segmented mirror arrays [PDF]

, 1992
A method and an apparatus are disclosed for edge phasing an array of segments in a segmented primary telescope mirror using white light from a far field source and starting with the inner edge of each segment in the first ring of segments.
Manhart, Paul K.
core   +1 more source

On High-Contrast Characterization of Nearby, Short-Period Exoplanets with Giant Segmented-Mirror Telescopes

, 2013
Measurements of the frequency with which short-period planets occur around main sequence stars allows a direct prediction of the number and types of such planets that will be amenable to characterization by high-contrast instruments on future giant ...
Crossfield, Ian J. M.
core   +1 more source

Multimodal Data‐Driven Microstructure Characterization

Advanced Engineering Materials, EarlyView.
A self‐consistent autonomous workflow for EBSP‐based microstructure segmentation by integrating PCA, GMM clustering, and cNMF with information‐theoretic parameter selection, requiring no user input. An optimal ROI size related to characteristic grain size is identified.
Qi Zhang, Santiago Benito, Özge Özgün, Sebastian Weber, Markus Stricker   +4 more
wiley   +1 more source

Keck Primary Mirror Closed-loop Segment Control Using a Vector-Zernike Wavefront Sensor

The Astrophysical Journal
We present the first on-sky segmented primary mirror closed-loop piston control using a Zernike wavefront sensor (ZWFS) installed on the Keck II telescope.
Maïssa Salama, Charlotte Guthery, Vincent Chambouleyron, Rebecca Jensen-Clem, J. Kent Wallace, Jacques-Robert Delorme, Mitchell Troy, Tobias Wenger, Daniel Echeverri, Luke Finnerty, Nemanja Jovanovic, Joshua Liberman, Ronald A. López, Dimitri Mawet, Evan C. Morris, Maaike van Kooten, Jason J. Wang, Peter Wizinowich, Yinzi Xin, Jerry Xuan   +19 more
doaj   +1 more source