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Showing papers on "Moiré pattern published in 2011"


Journal ArticleDOI
TL;DR: A Talbot-Lau interferometer using two-dimensional gratings and a conventional x-ray tube has been used to investigate a phase-contrast imaging technique that is sensitive to phase gradients in two orthogonal directions and found that the choice of phase retrieval method made little difference in image blur.
Abstract: A Talbot–Lau interferometer using two-dimensional gratings and a conventional x-ray tube has been used to investigate a phase-contrast imaging technique that is sensitive to phase gradients in two orthogonal directions. Fourier analysis of Moire fringe patterns was introduced to obtain differential phase images and scattering images from a single exposure. Two-dimensional structures of plastic phantoms and characteristic features of soft tissue were clearly obtained at 17.5 keV. The phase-stepping technique was also examined to investigate the spatial resolution of different phase retrieval methods. In the presented setup we found that the choice of phase retrieval method made little difference in image blur, and a large effective source size was found to give a high intensity in the image plane.

71 citations


Journal ArticleDOI
TL;DR: Unified interpretation for the real and pseudo moiré phenomena using the concept of biased and unbiased frequency pairs in the Fourier spectrum is given.
Abstract: Unified interpretation for the real and pseudo moire phenomena using the concept of biased and unbiased frequency pairs in the Fourier spectrum is given Intensity modulations are responsible for pseudo moire appearance in the image plane rather than average intensity variations dominating real moire Detection of pseudo moire necessitates resolving superimposed structures in the image plane In the case of the product type superimposition generating both real and pseudo moire, our interpretation utilizes the Fourier domain information only The moire pattern characteristics such as an effective carrier, modulation and bias intensity distributions can be readily predicted We corroborate them using two-dimensional continuous wavelet transform and fast adaptive bidimensional empirical mode decomposition methods as complementary image processing tools

40 citations


Journal ArticleDOI
TL;DR: In this article, a two-dimensional phase analysis method using phase shifting moire patterns, which are generated computationally from a 2D grating image, was proposed for dynamic shape and strain measurement.
Abstract: Shape measurements and strain distribution measurements are important for analyzing the behavior of a rotating tire Recently, a two-dimensional phase analysis method using phase-shifting moire patterns, which are generated computationally from a two-dimensional grating image, was proposed This method is well suited to the dynamic shape and strain measurement because the phase can be accurately obtained from a two-dimensional grating image We show that it is possible to analyze the strain distribution and shape measurements of a moving object using a grating pattern attached to the surface of the specimen, and a dynamic shape and strain measurement system using the sampling moire method is developed in this paper The principle of the method and the experimental results of the method when applied to a rotating object are shown

25 citations


Journal ArticleDOI
TL;DR: The application of "parallel" moiré deflectometry in measuring the nonlinear refractive index of materials is reported, which allows one to measure the radius of curvature of the light beam by measuring themoiré fringe spacing.
Abstract: In this paper, the application of “parallel” moire deflectometry in measuring the nonlinear refractive index of materials is reported. In “parallel” moire deflectometry the grating vectors are parallel, and the resulting moire fringes are also parallel to the grating lines. Compared to “rotational” moire deflectometry and the Z-scan technique, which cannot easily determine the moire fringe’s angle of rotation and is sensitive to power fluctuations, respectively, “parallel” moire deflectometry is more reliable, which allows one to measure the radius of curvature of the light beam by measuring the moire fringe spacing. The nonlinear refractive index of the sample, including the sense of the change, is obtained from the moire fringe spacing curve. The method is applied for measuring the nonlinear refractive index of ferrofluids.

24 citations


Journal ArticleDOI
TL;DR: In this paper, the authors proposed a graphical method for determining the 2D displacement components from the moire patterns more easily instead of the complex Fourier transformation method, which is necessary to assume that the transmittance is sinusoidal.
Abstract: Purpose – Researchers in the past have used Fourier transformation method to determine the in‐plane displacement components from moire fringes generated by a pair of overlapping circular gratings. In this approach it is necessary to assume that the transmittance is sinusoidal. The purpose of this paper is to propose a graphical method for determining the 2D displacement components from the moire patterns more easily instead of the complex Fourier transformation method.Design/methodology/approach – The moire patterns were spatially transformed from Cartesian‐to‐polar coordinate system. The morphological grayscale dilation operation was used to eliminate the residual gratings in the transformed pattern while preserving the moire fringes. The center line of the moire fringe was fitted with a sine curve and the in‐plane displacement values were determined directly from the peak‐to‐valley height and the position of the peak in the fitted curve.Findings – Experimental results showed that the proposed moire patt...

23 citations


Journal ArticleDOI
TL;DR: An elegant technique for the simultaneous measurement of in-plane and out-of-plane displacements of a deformed object in digital holographic interferometry using sensitivity vectors of the optical configuration is proposed.
Abstract: This paper proposes an elegant technique for the simultaneous measurement of in-plane and out-of-plane displacements of a deformed object in digital holographic interferometry. The measurement relies on simultaneously illuminating the object from multiple directions and using a single reference beam to interfere with the scattered object beams on the CCD plane. Numerical reconstruction provides the complex object wave-fields or complex amplitudes corresponding to prior and postdeformation states of the object. These complex amplitudes are used to generate the complex reconstructed interference field whose real part constitutes a moire interference fringe pattern. Moire fringes encode information about multiple phases which are extracted by introducing a spatial carrier in one of the object beams and subsequently using a Fourier transform operation. The information about the in-plane and out-of-plane displacements is then ascertained from the estimated multiple phases using sensitivity vectors of the optical configuration.

23 citations


Journal ArticleDOI
TL;DR: In this paper, an optical method known as moire is proposed for acquiring quasi-simultaneous measurements of bed topography and flow depth in laboratory experiments based on projecting a fringe pattern (grating) on the bed and analyzing the deformation of the pattern caused by the topography with respect to a reference plane.
Abstract: . We describe an optical method known as moire for acquiring quasi-simultaneous measurements of bed topography and flow depth in laboratory experiments. The moire method is based on projecting a fringe pattern (grating) on the bed and analyzing the deformation of the pattern caused by the topography with respect to a reference plane. The height of the object is encoded in the phase of the pattern and can be retrieved either through Fourier transform or phase shifting algorithms. The methodology enables image-based non-contact measurements over a continuous surface at very high spatial and temporal resolutions. We use a commercial software package of a moire method called Light3D to map bed topography and flow depth in an experimental braided channel and demonstrate how the method can be used to characterize a full range of statistics not previously possible.

19 citations


Journal ArticleDOI
01 Mar 2011-Optik
TL;DR: In this article, a formulation of the moire phenomenon based on spatial averaging is presented which, without ignoring any of frequencies, leads to a smooth profile of the fringes of the original fringe pattern.

15 citations


Journal ArticleDOI
TL;DR: In this paper, the authors presented theoretical analysis and experimental verification of fringe multiplication under a scanning electron microscope (SEM) under the assumption of a 1000 lines mm−1 grating with the scanning lines of the SEM.
Abstract: In this study, theoretical analysis and experimental verification of fringe multiplication under a scanning electron microscope (SEM) are presented. Fringe multiplication can be realized by enhancing the magnification or the number of scanning lines under the SEM. A universal expression of the pitch of moire fringes is deduced. To apply this method to deformation measurement, the calculation formulas of strain and displacement are derived. Compared to natural moire, the displacement sensitivity is increased by fringe multiplication while the strain sensitivity may be retained or enhanced depending on the number of scanning lines used. The moire patterns are formed by the interference of a 2000 lines mm−1 grating with the scanning lines of SEM, and the measured parameters of moire fringes from experimental results agree well with theoretical analysis.

14 citations


Journal ArticleDOI
TL;DR: In this article, a two-dimensional (2-D) crack growth measurement method that uses moire fringes generated by circular gratings and pattern matching was developed in this work for application in structural health monitoring.
Abstract: A two-dimensional (2-D) crack growth measurement method that uses moire fringes generated by circular gratings and pattern matching was developed in this work for application in structural health monitoring. The moire fringe patterns were extracted by transforming the circular gratings into linear gratings using polar-radius transformation and applying a one-dimensional average filter. The filtered image was inversely transformed to recover the moire fringes. Pattern matching was performed by comparing the absolute difference between an input fringe pattern caused by an unknown displacement and a series of reference fringe patterns of known displacements in one direction. The matching of the moire fringes caused by displacement at 90° to that in the reference patterns and combination of the two orthogonal directions was carried out after applying a rotational angle search algorithm. Demonstration using a crack model showed the applicability of the proposed system for the measurement of relative displacement of crack development along two directions with a sensitivity of 0.02 mm. The measured displacements were found to have high correlation with the actual displacements with a R2 value of 0.9985. Copyright © 2010 John Wiley & Sons, Ltd.

13 citations


Journal ArticleDOI
TL;DR: The interpretation, which is consistent with the Fourier theory when the two superposed gratings are periodic, involves only the image domain and shows remarkable simplicity, just like the indicial equation method.
Abstract: We propose an interpretation of moire phenomenon in the image domain. The interpretation is basically based on the analysis of the waveform of the line families. The period, angle, and intensity profile of moire fringes can be obtained directly in the image domain according to this interpretation. Moreover, pseudo-moire can be interpreted visually with the consideration of the illusional contrast of the human visual system. The interpretation, which is consistent with the Fourier theory when the two superposed gratings are periodic, involves only the image domain and shows remarkable simplicity, just like the indicial equation method.

Journal ArticleDOI
TL;DR: In this article, an auto-focus system based on the moire effect and a feedback control method is presented, where a collimated laser beam passes through a focusing lens then falls incident on the surface of the sample.

Journal ArticleDOI
TL;DR: In this paper, the sampling moire method is used to analyze phases of a moire fringe and a grating from one image of one grating pattern, it is possible to analyze dynamic deformation accurately.
Abstract: Moire method is a useful method to measure deformation and strain distribution of structures. Moire fringe patterns are analyzed quantitatively and speedy by image processing using a computer. In this paper, the theory of moire method and sampling moire method is introduced. Since the sampling moire method is useful to analyze phases of a moire fringe and a grating from one image of a grating pattern, it is possible to analyze dynamic deformation accurately. Some applications of the sampling moire method to displacement measurement of a beam, and shape and strain measurement of a rubber structure are shown.

Journal ArticleDOI
01 Jun 2011-Strain
TL;DR: In this article, exact formulas describing the observed shift of projected moire grating lines on a surface of an object are derived for the paraxial model, which enable to construct more accurate explicit relationship among the amplitude of oscillation, the pitch of the projected grating and the order of the fringe.
Abstract: New exact formulas describing the observed shift of projected moire grating lines on a surface of an object are derived for the paraxial model. These formulas enable to construct more accurate explicit relationship among the amplitude of oscillation, the pitch of the projected grating and the order of the fringe. Analytical derivations and numerical illustrations are used throughout the text to explain the process of formation of double-exposure and time-averaged projection moire fringes.


Journal ArticleDOI
TL;DR: In this article, a dual phase-shifting moire projection method is proposed for microscopic three-dimensional surface profilometry, which combines a combination of the deformed fringe detected from the object's surface and a virtual sinusoidal grating self-generated by the computer.

Proceedings ArticleDOI
25 Aug 2011
TL;DR: In this paper, a Charge Coupled Device (CCD) is used for capturing the numerical moire fringe, substituting for the usual photodetector, which can be used for measuring the displacement of the object.
Abstract: Moire fringe can be used for measuring the displacement of the object. In this paper, Charge Coupled Device (CCD) is used for capturing the numerical moire fringe, substituting for the usual photodetector. The movable grating is labeled by the special figure, which moves in the moire fringe with the movable grating moving. The original position serves as the reference, and the special figure is searched for in the moire fringe by the correlation operation to determine its shift of pixel in the screen, then by the calibration value to calculate the displacement of the measured object. This method does not need to count the shifting number of the moire fringe. However the lateral magnifying power of lens is considered seriously.

Journal ArticleDOI
TL;DR: A sampling moire camera which can analyze grating phase in real time is developed and an application on a real-time deformation measurement of a cantilever is demonstrated.
Abstract: Sampling Moire method is one of the convenient phase analysis methods. The accuracy of phase difference analysis is from 1/100 to 1/1000 of the grating pitches. This method is useful for a real-time measurement because the phase analysis can be performed from a single-shot image. In this paper, we developed a sampling moire camera which can analyze grating phase in real time. This camera is composed of a CMOS sensor and a FPGA. A two-dimensional grating image taken by the CMOS sensor was analyzed by the FPGA in real time. An application on a real-time deformation measurement of a cantilever is demonstrated.

Journal ArticleDOI
TL;DR: In this paper, the use of optical full-field measurement techniques has been used for the analysis of vibrations and mode shape extraction for a wide range of applications, including mode shape analysis.
Abstract: For the analysis of vibrations and mode shape extraction in particular the use of optical full-field measurement techniques has grown during the last years. Beside techniques like Digital Speckle Pattern Interferometry, Moire, Thermography or Photoelasticity the Digital Image Correlation techniques have already been successfully proven to be an accurate displacement analysis tool for a wide range of applications.

Book ChapterDOI
01 Jan 2011
TL;DR: Sampling moire method as discussed by the authors is a newly developed Moire method using an image processor for a grating pattern to measure shape or displacement or strain distributions, the phase analysis of moire pattern provides accurate result of displacement of the grating.
Abstract: Sampling moire method is a newly developed moire method using an image processor for a grating pattern to measure shape or displacement or strain distributions. A grating pattern on an object is recorded by a digital camera. Though the digitized image shows the grating, a moire fringe pattern appears by thinning-out the pixels, i.e., sampling the image with a larger pitch than the pixel pitch. If the sampling pitch is changed, the moire pattern is changed very much. If the phase of the sampling is changed, the phase of the moire pattern is changed. The phase analysis of moire pattern provides accurate result of displacement of the grating. If the number of the phase-shifted moire patterns i.e. the number of pixels for a pitch of grating is larger, the resolution of phase analysis becomes more accurate but the spatial resolution becomes worse. Since the sampling moire method is useful to analyze the phases of a moire fringe and a grating from one image of a grating pattern, it is possible to analyze dynamic deformation accurately.

Proceedings ArticleDOI
TL;DR: A detailed review of 3D-SIM hardware with the goal of super-resolved z-stacks of motile cells can be found in this article, where a series of images is required, wherein the 3D pattern is shifted and rotated, providing down-mixed data for a system of linear equations.
Abstract: Three-dimensional structured illumination microscopy achieves double the lateral and axial resolution of wide-field microscopy, using conventional fluorescent dyes, proteins and sample preparation techniques. A three-dimensional interference-fringe pattern excites the fluorescence, filling in the "missing cone" of the wide field optical transfer function, thereby enabling axial (z) discrimination. The pattern acts as a spatial carrier frequency that mixes with the higher spatial frequency components of the image, which usually succumb to the diffraction limit. The fluorescence image encodes the high frequency content as a down-mixed, moire-like pattern. A series of images is required, wherein the 3D pattern is shifted and rotated, providing down-mixed data for a system of linear equations. Super-resolution is obtained by solving these equations. The speed with which the image series can be obtain ed can be a problem for the microscopy of living cells. Challenges include pattern-switchi ng speeds, optical efficiency, wavefront quality and fringe contrast, fringe pitch optimization, and polarization issues. We will review some recent developments in 3D-SIM hardware with the goal of super-resolved z-stacks of motile cells. Keywords: super-resolution, 3D-SIM, moire

Journal ArticleDOI
01 Apr 2011
TL;DR: In this article, small in-plane angular displacement is determined by adopting two matched moire fringes and frequency analysis method in the case of a 2-DOF femtogram.
Abstract: Small in-plane angular displacement is determined by adopting two matched moire fringes and frequency analysis method in this paper. The gratings in the specimen and reference have a complementary ...

Proceedings ArticleDOI
TL;DR: This paper addresses issues on finding optimal color screen sets which produce the minimal visible moiré and homogeneous halftone texture and proposes new features includingHalftone microtexture spectrum analysis, common periodicity, and twist factor to achieve these goals.
Abstract: For electrophotographic printers, periodic clustered screens are preferable due to their homogeneous halftone texture and their robustness to dot gain. In traditional periodic clustered-dot color halftoning, each color plane is independently rendered with a different screen at a different angle. However, depending on the screen angle and screen frequency, the final halftone may have strong visible moire due to the interaction of the periodic structures, associated with the different color planes. This paper addresses issues on finding optimal color screen sets which produce the minimal visible moire and homogeneous halftone texture. To achieve these goals, we propose new features including halftone microtexture spectrum analysis, common periodicity, and twist factor. The halftone microtexture spectrum is shown to predict the visible moire more accurately than the conventional moire-free conditions. Common periodicity and twist factor are used to determine whether the halftone texture is homogeneous. Our results demonstrate significant improvements to clustered-dot screens in minimizing visible moire and having smooth halftone texture.

Journal ArticleDOI
01 Jan 2011
TL;DR: In this paper, the Fourier transform profilometry technique is applied in the projected moire fringe pattern onto an object surface, and a phase map is generated using phase unwrapping.
Abstract: In the present work is proposed that dynamic moire-like fringe patterns produced by photorefraction, with low spatial frequencies, could be used for profile determination of small objects. The Fourier transform profilometry technique is applied in the projected moire fringe pattern onto an object surface. Basically, the Fourier transform of the projected fringes is obtained. After that, a phase map is generated. Then, the optical profile of object is obtained using phase unwrapping. So, the entire process can be indicated to measure, with good accuracy degree, profile of small objects in sub-micrometer scale in optical mechanical systems.

Patent
08 Jul 2011
TL;DR: In this paper, a first fundamental frequency vector and a second fundamental vector of a halftone cell are sheared using a selected shearing value, which is selected as an offset in a fast scanning or slow scanning direction.
Abstract: As set forth herein, computer-implemented methods and systems facilitate the generation of halftone screens for moire-free color halftoning. A first fundamental frequency vector and a second fundamental frequency vector of a halftone cell are sheared using a selected shearing value. The shearing value is selected as an offset in a fast scanning or slow scanning direction. The selected shearing value satisfies various moire-free conditions associated with the identified frequency vectors and is capable of being selected for multiple halftone screens. The halftone screens generated using the sheared frequency vectors are used for moire-free halftoning.

Book
01 Jan 2011
TL;DR: In this paper, the authors present a framework for multiscale modeling of 3D X-ray structures of alloys and nanoparticles using Electron Tomography (Tomography).
Abstract: 3D Structures of Alloys and Nanoparticles Observed by Electron Tomography (40 minute presentation).- Damage Characterization in Dual-phase Steels Using X-ray Tomography.- In-situ Synchrotron-radiation Computed Laminography Observation of Ductile Fracture.- Understanding the Mechanical Behaviour of a High Manganese TWIP Steel by the Means of in Situ 3D X ray Tomography.- Mechanical Properties of Monofilament Entangled Materials.- Caracterisation of Mechanical Properties of Cellular Ceramic Materials Using X-ray Computed Tomography.- Multiaxial Stress State Assessed by 3D X-ray Tomography on Semi-crystalline.- Polymers.- Effect of Porosity on the Fatigue Life of a Cast al Alloy.- Fatigue Mechanisms of Brazed Al-Mn Alloys Used in Heat Exchangers.- Three Dimensional Confocal Microscopy Study of Boundaries between Colloidal Crystals.- Scale Independent Fracture Mechanics.- Keynote Presentation (40 minutes).- Consistent Embedding: A Theoretical Framework for Multiscale Modeling.- Analysis of Crystal Rotation by Taylor Theory.- Keynote Presentation (40 minutes).- Numerical Solution of the Walgraef-aifantis Model for Simulation of Dislocation Dynamics in Materials Subjected to Cyclic Loading.- Photoelastic Determination of Boundary Condition for Finite Element Analysis.- Discussion on Hybrid Approach to Determination of Cell Elastic Properties.- Mesh Refinement for Inverse Problems With Finite Element Models.- Assessment of Inverse Procedures for the Identification of Hyperelastic Material Parameters.- Digital Image Correlation Through a Rigid Borescope.- Scale Independent Approach to Strength Physics and Optical Interferometry.- Keynote Presentation (40 minutes).- Optical Techniques That Measure Displacements: A Review of the Basic Principles.- Studying Phase Transformations in a Shape Memory Alloy With Full-field Measurement Techniques.- Correlation between Mechanical Strength and Surface Conditions of Laser Assisted Machined Silicon Nitride.- Analysis of Speckle Photographs by Subtracting Phase Functions of Digital Fourier Transforms.- Measurement of Residual Stresses in Diamond Coated Substrates Utilizing Coherent Light Projection Moire Interferometry.- Automatic Acquisition and Processing of Large Sets of Holographic Measurements in Medical Research.- Adaptative Reconstruction Distance in a Lensless Digital Holographic Otoscope.- 3D Shape Measurements With High-speed Fringe Projection and Temporal Phase Unwrapping.- Measuring Local Mechanical Properties of Membranes Applying Coherent Light Projection Moire Interferometry.- Experimental Analysis of Foam Sandwich Panels With Projection Moire.- Panoramic Stereo DIC-based Strain Measurement on Submerged Objects.- Advances in the Measurement of Surfaces Properties Utilizing Illumination at Angles Beyond Total Reflection.- Filters with Noise/Phase Jump Detection Scheme for Image Reconstruction.- An Instantaneous Phase Shifting ESPI System for Dynamic Deformation Measurement.- Development of Linear LED Device for Shape Measurement by Light Source Stepping Method.- Calibration Method for Strain Measurement Using Multiple Cameras in Digital Holography.- Performance Assessment of Strain Measurement With an Ultra High Speed Camera.- Rigid Body Correction Using 3D Digital Photogrammetry for Rotating Structures.- Development of Sampling Moire Camera for Landslide Prediction by Small Displacement Measurement.- Energy Dissipation in Impact Absorber.- Mechanics Behind 4D Interferometric Measurement of Biofilm Mediated Tooth Decay.- Validating Road Profile Reconstruction Methodology Using ANN Simulation on.- Experimental Data.- Electro-optical Property of Sol-gel-derived PLZT7/30/70 Thin Films.- Decoupling six Effective Parameters of Anisotropic Optical Materials Using Stokes Polarimetry.- Measurement of Creep Deformation in Stainless Steel Welded Joints.- Thermal Deformation Measurement in Thermoelectric Coolers by ESPI and DIC Method.- Structural Health Monitoring Using Digital Speckle Photography.- Determining the Strain Distribution in Bonded and Bolted/Bonded Composite Butt Joints Using the Digital Image Correlation Technique and Finite Element Methods.- Improved Spectral Approach for Continuous Displacement Measurements From Digital Images.- Experimental Testing (2D DIC) and FE Modelling of T-stub Model

Patent
16 Nov 2011
TL;DR: In this article, a method of assembling autostereoscopic display is described, where 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.
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.

Book ChapterDOI
13 Dec 2011
TL;DR: The feedbacks indicate that this technique is low cost, simple and powerful method in 3D reconstruction of every surface without any disturbance.
Abstract: The aim of this paper is 3D machine vision of surface based on optical phase shift Moire. In measurement process we generate Moire contours on a surface by using shadow moire technique. The current work use phase shift analysis in order to increase the accuracy of measurement and extract the 3D profile of surface. In comparison with recent methods this technique is simple and easy to implement. In order to show validity and feasibility of this method, we apply it on a human face. The feedbacks indicate that this technique is low cost, simple and powerful method in 3D reconstruction of every surface without any disturbance.

Proceedings ArticleDOI
09 May 2011
TL;DR: In this paper, a phase-shifting digital holography which is available simply with single-shot exposure of holograms without any special phaseshifting device is proposed, where the phase shifting property in three or four moire patterns obtained from single holograms with a large spatial carrier is demonstrated.
Abstract: Phase-shifting digital holography which is available simply with single-shot exposure of holograms without any special phase-shifting device is proposed. A key point of the present method is phase-shifting property in three or four moire patterns obtained from single holograms with a large spatial carrier by sampling sparsely in a computer. Theoretical analysis is performed for demonstrating the phase-shifting property of these sparsely-sampled hologram patterns from the single hologram. Limits of a carrier frequency, i.e., amount of tilting angle of the reference plane wave used in recording holograms, and a phase slope of the object wave to be reconstructed are also given by theoretical analysis. Numerical simulations are conducted for demonstrating the validity and the limits of the proposed method.

Proceedings ArticleDOI
05 Aug 2011
TL;DR: The results show that the spLicing model and the moire patterns processing algorithm is accurate and feasible, and another kind to be able the quota examination aspheric surface method is proposed.
Abstract: sub-region stitching measurement of a sphere by using the combination of digital moire patterns witHout compensator, auxiLiary mirror, hologram and other assistant modules. This paper illustrated the basic theory. And use of digital filtering, phase shifting, the least square method and Zernike polynomial fitting to estabLish the reasonable mathematical model. Meanwhile the computer simulation experiment was carried on. the PV and RMS of the full aperture phase distribution residual error are 0.072λand 0.0092#x03BB; After this method processing. The results show that the spLicing model and the moire patterns processing algorithm is accurate and feasible, Thus proposed another kind to be able the quota examination aspheric surface method.