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.

Fresnel zone plate moire patterns and its metrological applications

Abstract: There are given equations describing the basic grids, which superimposed with themself, create the moire pattern in the form of the spherical, equilateral hyperbolic, and linear zone plates. All cases are derived for mutual displacements performed by translations along the axes of the coordinate system and by rotations. A family of basic grids set up a complete set of solutions. Moire zone plates can serve as imaging elements with very long, variable focal length, and have an application in alignment in the technique of three points.

Moiré effect-based interference microscopy for biospecimen characterization

Abstract: Interference microscopy for biospecimen characterization based on the moire phenomena is described. Two scenarios of incoherent multiplicative superimposition are employed: (1) object information carrying interferogram is superimposed with reference one or (2) two object interferograms are superimposed (with equal or opposite phase signs). Second strategy provides additional doubling of underlying phase function of interest. Superimposition can be performed using two experimental interferograms or single real interferogram and numerically designed reference structure in so-called digital moire regime. Multiplicative superimposition of two periodic intensity distribution yields moire pattern containing low spatial frequency difference beat term (moire fringes – macrostructure) and high spatial frequency sum beat term (microstructure). The macrostructure was studied in great majority of previously reported moire techniques. In this contribution we point attention onto the sum beat spatial frequency component and report efficient means for its recovery using numerically advanced digital filtering (variational/empirical decomposition approaches). Its single-frame (single-pattern) phase demodulation by 2D Hilbert spiral transform with enhanced accuracy follows - this feature comes from the fact that sum beat moire term has high spatial frequency which is generally beneficial in single-frame fringe analysis and its phase function is be doubled. In particular spatial phase change is better sampled by fringes for denser interferogram and more importantly numerical filtering of fringe term of interest from background intensity is easier. We propose and preliminarily evaluate experimental proof-of-concept strategy where two interferograms with slight difference in spatial frequency are simultaneously recorded in two halves of CCD camera and superimposed multiplicatively. Proposed moire technique opens up new possibilities in interference microscopy based bio-phase imaging mainly due to its data-driven enhanced phase sensitivity (fringe doubling effect) and real-time operation. Evaluation employing numerical simulations and validation using experimental recordings of phase bio-samples, i.e., prostate cancer cells are enclosed.

Shape measuring device using moire optical system and its method

Abstract: PROBLEM TO BE SOLVED: To provide a device for measuring the shape of a moving planar component such as a roller component or a sheet by changing a distance d between a light source and an observation point for shifting the phase of moire fringes by applying a phase shifting method to a moire method. SOLUTION: The shape measuring device uses a solid lattice type moire optical system which consists of the light sources for generating the moire fringes, a patterned lattice, a lens for imaging the moire fringes of the patterned lattice, and a light receiving element. The light receiving element consists of a pixel array with accumulated pixels, and at least three light sources are arranged at positions differently distant from the lens. The pixel array constituting the light receiving element uses the moire optical system, which consists of a means for controlling the light sources to be lit in sequence in synchronization with the scanning cycles of the pixel array, a mechanism for moving a relative position relationship between the moire optical system and a planar inspected surface to the direction perpendicular to the pixel array of the light receiving element, a shape computing means for calculating the shape of the circular or planar inspected surface using the phase shifting method from data for the pixel array, for measuring the shape of a cylindrical or planar inspected object. COPYRIGHT: (C)2004,JPO

Method of assembling autostereoscopic display

Abstract: A method of assembling autostereoscopic display is disclosed. The characteristic of the method is that a display panel shows a stripe pattern of specific two-dimensional images with a predetermined pitch, and a Moire pattern is formed with the stripe pattern and a three-dimensional image generated layer. And by observing the Moire pattern, the three-dimensional image generated layer can be perfectly aligned to the display panel.

Topological network and valley beam splitter in acoustic biaxially strained moiré superlattices

Abstract: Moir\'e superlattices consist of parallel but staggered periodic lattices and have been extensively explored due to their salient physical properties. However, there are limited demonstrations of such concepts for classical wave systems. Here, we construct an acoustic biaxially strained moir\'e superlattice by mismatching lattice constants in both $x$ and $y$ directions. The interface between two different topological regions with opposite valley Chern numbers forms a valley-induced network along which acoustic waves can travel efficiently. Taking a unit cell from the superlattice as a six-terminal device, the incoming acoustic waves can be partitioned into the left-adjacent, the right-adjacent, and the forward-facing channels. The acoustic beam splitting is protected by the valley polarization. Our results provide a comprehensive analysis of the transport properties of acoustic waves in the moir\'e superlattice and can provide useful insights for designing topological acoustic devices ranging from topological networks, valley filters, to energy splitters.