SPECKLE INTERFEROMETRY AT MOUNT WILSON OBSERVATORY: OBSERVATIONS OBTAINED IN 2006-2007 AND 35 NEW ORBITS

In this study, a compound speckle interferometer for measuring three-degree-of-freedom (3-DOF) displacement is proposed. The system, which combines heterodyne interferometry, speckle interferometry and beam splitting techniques, can perform precision 3-DOF displacement measurements, while still having the advantages of high resolution and a relatively simple configuration. The incorporation of speckle interferometry allows for non-contact displacement measurements by detecting the phase of the speckle interference pattern formed from the convergence of laser beams on the measured rough surface. Experiments were conducted to verify the measurement capabilities of the system, and the results show that the proposed system has excellent measurement capabilities suitable for future real-world applications.

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Microshape Measurement Method Using Speckle Interferometry Based on Phase Analysis

Photonics ◽

10.3390/photonics8040112 ◽

2021 ◽

Vol 8 (4) ◽

pp. 112

Author(s):

Yasuhiko Arai

Keyword(s):

Fine Structure ◽

Phase Analysis ◽

Measurement Method ◽

Phase Distribution ◽

Periodic Structures ◽

Scattered Light ◽

Speckle Interferometry ◽

Diffraction Limit ◽

Silica Microspheres ◽

Measured Object

A method for the measurement of the shape of a fine structure beyond the diffraction limit based on speckle interferometry has been reported. In this paper, the mechanism for measuring the shape of the fine structure in speckle interferometry using scattered light as the illumination light is discussed. Furthermore, by analyzing the phase distribution of the scattered light from the surface of the measured object, this method can be used to measure the shapes of periodic structures and single silica microspheres beyond the diffraction limit.

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A Whole-Field Interferometric Scheme for Measuring strain and Flow Rates of Glacier and Other Natural Surfaces

Journal of Glaciology ◽

10.3189/s0022143000030392 ◽

1983 ◽

Vol 29 (103) ◽

pp. 492-497

Author(s):

Gary Cloud ◽

Edgar Conley

Keyword(s):

Displacement Vector ◽

Surface Displacement ◽

Time Lapse ◽

Speckle Interferometry ◽

Narrow Beam ◽

Coherent Light ◽

Ice Surface ◽

Glacier Ice ◽

Fringe Patterns ◽

Small Overlap

AbstractThe flow of glacier ice is mapped using high-resolution photography and non-coherent-light speckle interferometry. Young’s fringe patterns result when a double-exposed photoplate image of the straining surface is illuminated by a narrow beam of coherent light. Geometry gives a relationship between the ice surface displacement vector and the interference fringe patterns. This displacement vector is corrected for rigid-body (camera) movement and projected onto the ice surface using topological maps. The strain during the time-lapse interval is thus known. Comparison with data acquired by surveying techniques at Nisqually Glacier, Washington, U.S.A., is limited because of small overlap of the surface studied. In the areas for which results can be compared, our experiments yield a flow of 0.6 m/d where conventional methods yield about 0.4 m/d.

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Fast Drift-Scan CCD Imaging and Photometry with Small Telescopes: Lunar Occultations and Speckle Interferometry

International Astronomical Union Colloquium ◽

10.1017/s0252921100079148 ◽

2001 ◽

Vol 183 ◽

pp. 309-314

Author(s):

Jorge Núñez ◽

Octavi Fors

Keyword(s):

Data Analysis ◽

Speckle Interferometry ◽

Close Binary ◽

Ccd Cameras ◽

Ccd Imaging ◽

Scanning Technique ◽

Photometric Observations ◽

Drift Scan ◽

Fast Drift ◽

Year 2000

AbstractIn this paper we show how inherent features of typical CCD cameras can be used for fast (in the order of milliseconds) photometric observations (FPO), even with submeter class telescopes. This is based on a modified drift-scanning technique which we show to be advantageous for such kind of observations. In particular, we successfully carried out some lunar occultations and speckle interferometry observations using this technique. During the year 2000, we registered several occultation events. In particular, we present the occultation of SAO79031. The millisecond photometry of the event allows us subsequent data analysis for stellar diameter estimation and close binary detection. We also show an example of the application of the technique to speckle interferometry observations. Finally, we present the main characteristics of our project to build a new remotely controlled observatory near Barcelona.

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