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Moiré pattern

About: Moiré pattern is a research topic. Over the lifetime, 1917 publications have been published within this topic receiving 27176 citations. The topic is also known as: moiré fringes & moire pattern.


Papers
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Journal ArticleDOI
Dorian Kermisch1, Paul G. Roetling1
TL;DR: An analytic expression has been developed that can be used for computing the Fourier spectrum of any halftone image as a function of the original continuous-tone image and theHalftone process, and takes into account the nonlinear effects of the threshold step in the halft one process.
Abstract: An analytic expression has been developed that can be used for computing the Fourier spectrum of any halftone image as a function of the original continuous-tone image and the halftone process. This result takes into account the nonlinear effects of the threshold step in the halftone process. Although the result is general and can be applied to any original image, in some cases of periodic images the Fourier components of the halftone image are particularly easy to compute. We show important differences between spectra of halftone images and scanned or sampled images. In halftone images, significant image detail is maintained at spatial frequencies greater than half of the screen frequency and aliasing or moire patterns depend upon object contrast and upon the halftone function differently from similar patterns which occur in scanned or sampled imagery.

80 citations

Journal ArticleDOI
TL;DR: In this paper, a fine micrograting prepared by electron beam lithography is used as a model grating, and a scanning exposure ofthe primary electron beam in a scanning electron microscope (SEM) as a master grating.
Abstract: Microcreep deformations in pure copper specimens are studied by a new moire method. In this method, a fine micrograting prepared by electron beam lithography is used as a model grating, and a scanning exposure ofthe primary electron beam in a scanning electron microscope (SEM) as a master grating. The scanning exposure of the electron beam on the specimen with the model grating produces moire fringes of bright and dark lines formed in response to the different amounts of the emitted secondary electrons for each primary electron. This new method makes it possible to obtain a clear and fine moire fringe without an image-processing system and to observe the moire fringe pattern and the SEM image at the same time. By this method, the inhomogeneous microcreep deformations such as grain boundary sliding, coarse slip, and localized strain are measured with high accuracy. It is confirmed that the creep strain is nonuniform even in the same grain and the strain distribution is caused mainly by the grain boundary sliding.

80 citations

Proceedings ArticleDOI
09 Feb 1996
TL;DR: Some of the techniques for creating fringe pattern images were presented along with methods of analysis and possible applications of interferometric methods, especially in the field of experimental orthopedics, endoscopy and ophthalmology will be pointed out.
Abstract: Optical metrology based on the principle of interference can be applied as a testing tool in biomedical research. Interferograms in form of fringe patterns can be produced in two-beams interferometers, holographic or speckle interferometers, in setups realizing moire techniques or in deflectometers. By analyzing of the fringe pattern images, information about the shape or mechanical behavior of the object under study can be retrieved. Here, some of the techniques for creating fringe pattern images were presented along with methods of analysis. Possible applications of interferometric methods, especially in the field of experimental orthopedics, endoscopy and ophthalmology will be pointed out.

79 citations

Journal ArticleDOI
Olof Bryngdahl1
TL;DR: The superposition of several periodic or quasiperiodic patterns produces moire effects as discussed by the authors, and the combination of three grid structures adds great flexibility to the use of moire phenomena.
Abstract: The superposition of several periodic or quasiperiodic patterns produces moire effects. In particular, the combination of three grid structures adds great flexibility to the use of moire phenomena. Information about the fringe structure, given by vector addition in Fourier space, allows investigation of formations, interpretation, and expectation problems concerning moire-pattern parameters. Any frequency and orientation of the pattern is possible, using three-line gratings. On the other hand, three quasiperiodic gratings with variations of frequency and/or orientation result in a zone-plate shape of the moire pattern regardless of grating distortions. Both elliptical and hyperbolic zone plates occur. Several illustrations demonstrate these phenomena and indicate some potential applications.

79 citations

Patent
21 Dec 2007
TL;DR: In this paper, the authors used time averaged Moire patterns to tailor uniformity of the image by controlling both the near field and far field regions of the display to result in a stable and uniform scanned beam display image.
Abstract: Briefly, in accordance with one or more embodiments, time averaged Moire patterns may be utilized in a scanned beam display having a Gaussian beam profile or the like in order to tailor uniformity of the image by controlling both the near field and far field regions of the display to result in a stable and uniform scanned beam display image. Consideration is made regarding the light source parameters of focus numerical aperture, profile, shape, and/or wavelength to achieve higher uniformity and stability without resulting in significant visible coherent artifacts such as tiled intensity patterns and/or Moire.

77 citations


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Performance
Metrics
No. of papers in the topic in previous years
YearPapers
2023181
2022321
202126
202048
201946
201844