Topic
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 published on a yearly basis
Papers
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TL;DR: In this article, the authors proposed and experimentally verified two approaches, namely phase shifting of the carrier interference pattern and auxiliary carrier fringe generation with subsequent optical filtering, for additive and multiplicative CHMI.
Abstract: Comparative holographic moire interferometry (CHMI) permits defect detection by comparison of the mechanical responses of two macroscopically identical specimens at equal loading. In the present work a technique of moire fringe separation is suggested that is amenable to automatic readout. Two approaches are proposed and experimentally verified: phase shifting of the carrier interference pattern and auxiliary carrier fringe generation with subse-quent optical filtering. The phase shifting method is applicable to an additive moire scheme with two reference beams. Auxiliary carrier fringe generation can be used in both additive and multiplicative CHMI. The frequency constraints of the latter method due to the optical recording arrangement and mechanical responses of the tested specimen are analyzed.
12 citations
TL;DR: This work describes a novel approach of strain segmentation for the moire pattern using a multichannel Gabor filter that allows for user-specific segmentation, which is essentially in engineering design and analysis.
Abstract: Moire interferometry is a powerful technique for high sensitivity in-plane deformation contouring. However, from an engineering viewpoint, the derivatives of displacement, i.e., strain, are the desired parameter. Thus there is a need to differentiate the displacement field. Optical and digital methods have been proposed for this differentiation. Optical methods provide contours that still need to be quantified, while digital methods suffer from drawbacks inherent in the digital differentiation process. We describe a novel approach of strain segmentation for the moire pattern using a multichannel Gabor filter. Appropriate filter design allows for user-specific segmentation, which is essentially in engineering design and analysis.
12 citations
TL;DR: In this article, the effect of diffraction on the transmission pattern of a commercial Ronchi grid and the moire image of two equal Ronchi grids was measured and the best mode of experimental operation for creating moire images was determined.
Abstract: The best mode of experimental operation for creating moire images was determined. The effect of diffraction on the transmission pattern of a commercial Ronchi grid and the moire image of two equal Ronchi grids was measured. Transmission patterns and moire images at a wide range of conditions of two equal Ronchi grids with and without a phase object are presented. Deflection mapping of lenses by the moire method was carried out.
12 citations
TL;DR: The successful results verify the feasibility of the moire grating fabrication using electron beam lithography, and the grating has a good potential for further application.
12 citations
03 Sep 2001
TL;DR: Performance criteria for the images that measure when one superposition is better than another are introduced and are based on the visibility of the moirE patterns to the human visual system and on the digitization which takes place when presenting the images on discrete displays.
Abstract: MoirE phenomena occur when two or more images are nonlinearly combined to create a new "superposition image". MoirE patterns are patterns that don't exist in any of the original images but appear in the superposition image for example as the result of a multiplicative superposition rule. The topic of moirE pattern synthesis deals with creating images that, when superimposed, will reveal certain desired moirE patterns. Conditions ensuring that a desired moirE pattern will be present in the superposition of two images are known, however they do not specify these images uniquely. The freedom in choosing the superimposed images can be exploited to produce various degrees of visibility and ensure desired-properties. Performance criteria for the images that measure when one superposition is better than another are introduced. These criteria are basedon the visibility of the moirE patterns to the human visual system and on the digitization which takes place when presenting the images on discrete displays. We here propose to resolve the freedom in moirE synthesis by choosing the images that optimize the chosen criteria.
11 citations