Results 71 to 80 of about 28,711 (337)

Defocused Image Deep Learning Designed for Wavefront Reconstruction in Tomographic Pupil Image Sensors

Mathematics, 2020
Mathematical modelling methods have several limitations when addressing complex physics whose calculations require considerable amount of time. This is the case of adaptive optics, a series of techniques used to process and improve the resolution of ...
Sergio Luis Suárez Gómez, Francisco García Riesgo, Carlos González Gutiérrez, Luis Fernando Rodríguez Ramos, Jesús Daniel Santos   +4 more
doaj   +1 more source

Real-time Adaptive Optics with pyramid wavefront sensors: Accurate wavefront reconstruction using iterative methods

, 2018
In this paper, we address the inverse problem of fast, stable, and high-quality wavefront reconstruction from pyramid wavefront sensor data for Adaptive Optics systems on Extremely Large Telescopes.
Hutterer, Victoria, Ramlau, Ronny, Shatokhina, Iuliia   +2 more
core   +1 more source

Millisecond‐Switching Dual‐Band/Dual‐Polarization Ka‐Band Wavefront Control Enabled by a Complementary Liquid‐Crystal Metasurface

Advanced Materials Technologies, EarlyView.
An LCD‐compatible complementary liquid‐crystal metasurface delivers dual‐band, dual‐polarized Ka‐band wavefront control with millisecond switching via a 10‐µm LC gap. Interlaced patch/slot pairs enable independent phase tuning at 28 and 38 GHz, while strategic 45° slot rotation suppresses parasitic resonances. Measurements on a 160 × 160‐cell prototype
Daehyeon Kim, Donggeun An, Hyunjae Shin, Youngno Youn, Wonbin Hong   +4 more
wiley   +1 more source

Multi-Conjugate Adaptive Optics Simulator for the Thirty Meter Telescope: Design, Implementation, and Results

, 2018
We present a multi-conjugate adaptive optics (MCAO) system simulator bench, HeNOS (Herzberg NFIRAOS Optical Simulator). HeNOS is developed to validate the performance of the MCAO system for the Thirty Meter Telescope, as well as to demonstrate techniques
Andersen, David, Herriot, Glen, Lardiere, Olivier, Mieda, Etsuko, Rosensteiner, Matthias, Spano, Paolo, Turri, Paolo, Veran, Jean-Pierre   +7 more
core   +1 more source

Design and Fabrication of High Dielectric GRIN Lens for a Directive Antenna Using a Hybrid Filled Voxel Additive Manufacturing Technique

Advanced Materials Technologies, EarlyView.
Hybrid‐filled voxel AM enables integration of high‐permittivity materials into additively manufactured devices. Using this approach, a graded refractive index (GRIN) lens is demonstrated, achieving a 50% antenna size reduction with enhanced directivity.
Qianfang Zheng, Anna Radkovskaya, Kailun Xu, Ekaterina Shamonina, Patrick S. Grant   +4 more
wiley   +1 more source

Wavefront Derived Refraction and Full Eye Biometry in Pseudophakic Eyes. [PDF]

PLoS ONE, 2016
To assess wavefront derived refraction and full eye biometry including ciliary muscle dimension and full eye axial geometry in pseudophakic eyes using spectral domain OCT equipped with a Shack-Hartmann wavefront sensor.Twenty-eight adult subjects (32 ...
Xinjie Mao, James T Banta, Bilian Ke, Hong Jiang, Jichang He, Che Liu, Jianhua Wang   +6 more
doaj   +1 more source

CCD and Hartmann-Shack wavefront sensor to analyse holographic lens resolution [PDF]

, 2023
Tomás Lloret López, Víctor Navarro‐Fuster, Marta Morales‐Vidal, Manuel G. Ramírez, Andrés Márquez, Augusto Beléndez, Inmaculada Pascual   +6 more
openalex   +1 more source

ShaneAO: wide science spectrum adaptive optics system for the Lick Observatory

, 2014
A new high-order adaptive optics system is now being commissioned at the Lick Observatory Shane 3-meter telescope in California. This system uses a high return efficiency sodium beacon and a combination of low and high-order deformable mirrors to achieve
Cabak, Jerry, Deich, William, Dillon, Daren, Gates, John, Gavel, Donald, Kupke, Renate, Lanclos, Kyle, McGurk, Rosalie, Norton, Andrew, Peck, Michael, Pfister, Terry, Phillips, Andrew, Ratliff, Chris, Rockosi, Connie, Saylor, Michael, Srinath, Srikar, Ward, Jim   +16 more
core   +1 more source

Optical measurements of phase steps in segmented mirrors - fundamental precision limits [PDF]

, 2006
Phase steps are an important type of wavefront aberrations generated by large telescopes with segmented mirrors. In a closed-loop correction cycle these phase steps have to be measured with the highest possible precision using natural reference stars ...
Caianiello ER, Gonte F, Gonzalez JMR, H.-M. Adorf, Kendall M, L. Noethe, Pinna E   +6 more
core   +1 more source

Engineering Thermal Emission with Enhanced Emissivity and Quality Factor Using Bound States in the Continuum and Electromagnetically Induced Absorption

Advanced Optical Materials, EarlyView.
A metal‐based thermal metasurface supporting bound states in the continuum is demonstrated and experimentally shown to achieve a record‐high quality factor of 202 and high emissivity of 0.82. The design offers thermally stable, narrowband mid‐infrared emission, making it ideal for high‐precision gas sensing applications.
Guodong Zhu, Ikjun Hong, Kewei Li, Theodore Anyika, Maxwell T. Ugwu, J. Ryan Nolen, Mingze He, Joshua D. Caldwell, Justus C. Ndukaife   +8 more
wiley   +1 more source