Journal ArticleDOI
Simple model for image-plane polychromatic speckle contrast.
Reads0
Chats0
TLDR
A simple geometrical model was developed for calculation of the contrast of a polychromatic image-plane speckle pattern from a source of light with high spatial coherence and its validity was established by comparison with an exact solution.Abstract:
A simple geometrical model was developed for calculation of the contrast of a polychromatic image-plane speckle pattern from a source of light with high spatial coherence. It is based on counting the number of independent speckle patterns that contribute to a given point in the image plane. This results in a simple equation for the contrast as a function of imaging geometry; relative orientation of the projection direction, observation direction, and specimen normal; bandwidth of the light source; and surface roughness. Its validity was established by comparison with an exact solution: rms errors in the calculated contrast were only 0.033 over a wide range of parameter values likely to be encountered in practice.read more
Citations
More filters
Journal ArticleDOI
Design verification and validation in product lifecycle
Paul Maropoulos,Darek Ceglarek +1 more
TL;DR: This paper reviews the standard definitions of verification and validation in the context of engineering design and progresses to provide a coherent analysis and classification of these activities from preliminary design, to design in the digital domain and the physical verification and validate of products and processes.
Journal ArticleDOI
Robustness of reduced temporal phase unwrapping in the measurement of shape.
Lars Kinell,Mikael Sjödahl +1 more
TL;DR: The predictions of success rate and depth uncertainty for the negative exponential sequence used for temporal phase unwrapping of shape data are generalized to include the effect of a reduced sequence and speckle noise in single-channel and multichannel systems, respectively.
Journal ArticleDOI
Large volume metrology technologies for the light controlled factory
Jody Muelaner,Paul Maropoulos +1 more
TL;DR: In this paper, the authors describe the challenges of developing large volume measurement process models within an integrated dimensional variation management (IDVM) system and present a software for the planning and control of Integrated Metrology Networks based on quality control with uncertainty evaluation and control systems for predictive processes.
Journal ArticleDOI
Influence of geometry on polychromatic speckle contrast.
TL;DR: The Fresnel approach of diffraction theory for the free-space geometry is applied and a simple analytical relationship between contrast, coherence length, size of illuminated spot, and distances between source, object, and observation plane is derived.
Proceedings ArticleDOI
Optical shape measurement technology: past, present and future
TL;DR: In this paper, the authors provide an overview of the main competing optical technologies on which future commercial whole-field shape measurement systems are likely to be based, ranging from those based on pointwise techniques, such as laser triangulation and laser radar, to wholefield techniques such as projected fringes, Gray code methods and white light interferometry.
References
More filters
Journal ArticleDOI
Laser triangulation: fundamental uncertainty in distance measurement
TL;DR: The uncertainty limit in distance sensing by laser triangulation is discussed, and the same distance uncertainty that was obtained from a single-photon experiment and from Heisenberg's uncertainty principle is obtained.
Journal ArticleDOI
Surface Roughness Measurement Using White Light Speckle
TL;DR: Implementation techniques are discussed and results shown that indicate good correlation with profilometer measurements for a wide range of roughness values produced with a variety of finishing procedures.
Journal ArticleDOI
On the Contrast of Polychromatic Speckle Patterns and Its Dependence on Surface Roughness
TL;DR: In this paper, the contrast of a polychromatic speckle pattern can be calculated from the spectral coherence of the scattered amplitude, and the analytical relationship between the contrast and r.m.s. surface roughness is derived.
Journal ArticleDOI
Second-order Statistics of Light Diffracted from Gaussian, Rough Surfaces with Applications to the Roughness Dependence of Speckles
TL;DR: In this paper, the second-order statistics of light diffracted from gaussian rough surfaces are given by a locally stationary degree of coherence of scattered amplitudes in the reciprocal object space.
Journal ArticleDOI
Image-plane speckle in partially coherent illumination
TL;DR: In this article, the first and second order statistical properties of speckle formed in the image of a diffuse object when the illumination is both temporally and spatially partially coherent are derived.