Topic
Speckle imaging
About: Speckle imaging is a research topic. Over the lifetime, 3730 publications have been published within this topic receiving 62354 citations.
Papers published on a yearly basis
Papers
More filters
TL;DR: In this article, a video speckle camera has been designed, constructed, and successfully used to record data for a wide variety of astronomical objects, including solar features, and the problems associated with recovering images from specckle data have been explored extensively.
Abstract: : The hardware and software required to demonstrate and evaluate the speckle imaging process for use on solar features have been developed and tested. A video speckle camera has been designed, constructed, and successfully used to record data for a wide variety of astronomical objects, including solar features. The problems associated with recovering images from speckle data have been explored extensively. Particular attention has been given to identifying and correcting effects due to noise bias and edges in images reconstructed from real as well as simulated data. The principles involved in imaging solar features at improved resolution by means of speckle techniques have been delineated, and sample images recovered from a variety of test data. (Author)
16 citations
16 citations
TL;DR: In this article, the authors take advantage of the high temporal cadence (1 ms) of the data acquired by the System for Coronagraphy with High-order Adaptive Optics from R to K bands-VIS forerunner experiment at the Large Binocular Telescope to characterize the AO residual speckles at visible wavelengths.
Abstract: Residual speckles in adaptive optics (AO) images represent a well-known limitation on the achievement of the contrast needed for faint source detection. Speckles in AO imagery can be the result of either residual atmospheric aberrations, not corrected by the AO, or slowly evolving aberrations induced by the optical system. We take advantage of the high temporal cadence (1 ms) of the data acquired by the System for Coronagraphy with High-order Adaptive Optics from R to K bands-VIS forerunner experiment at the Large Binocular Telescope to characterize the AO residual speckles at visible wavelengths. An accurate knowledge of the speckle pattern and its dynamics is of paramount importance for the application of methods aimed at their mitigation. By means of both an automatic identification software and information theory, we study the main statistical properties of AO residuals and their dynamics. We therefore provide a speckle characterization that can be incorporated into numerical simulations to increase their realism and to optimize the performances of both real-time and postprocessing techniques aimed at the reduction of the speckle noise.
16 citations
TL;DR: A method of one-beam laser speckle interferometry was applied to the measurement of transient thermal strain fields in an aluminum plate heated at a small region and high quality isothetic fringe patterns were obtained.
Abstract: A method of one-beam laser speckle interferometry was applied to the measurement of transient thermal strain fields in an aluminum plate heated at a small region. A ruby pulse laser minimized the effect of thermal air turbulence on speckle correlation. High quality isothetic fringe patterns were obtained. The result compares well with available existing data.
16 citations
31 Oct 1997
TL;DR: In this paper, a simulation study of phase-diverse speckle satellite reconstructions for the Air Force Maui Optical station 1.6-meter telescope is presented, and the credibility of this study is enhanced by reconstructions from actual compensated data collected with the 1.5m telescope at the Starfire Optical Range.
Abstract: Space-object identification from ground-based telescopes is challenging because of the degradation in resolution arising from atmospheric turbulence. Phase-diverse speckle is a novel post-detection correction method that can be used to overcome turbulence-induced aberrations for telescopes with or without adaptive optics. We present a simulation study of phase-diverse speckle satellite reconstructions for the Air Force Maui Optical station 1.6-meter telescope. For a given turbulence strength, satellite reconstruction fidelity is evaluated as a function of quality and quantity of data. The credibility of this study is enhanced by reconstructions from actual compensated data collected wit the 1.5-meter telescope at the Starfire Optical Range. Consistent details observed across a time series of reconstructions from a portion of a satellite pass enhance the authenticity of these features. We conclude that phase-diverse speckle can restore fine-resolution features not apparent in the raw aberrated images of space objects.
16 citations