scholarly journals Roughness Measurements with Polychromatic Speckles on Tilted Surfaces

2021 ◽  
Author(s):  
Johannes Stempin ◽  
Andreas Tausendfreund ◽  
Dirk Stöbener ◽  
Andreas Fischer
Keyword(s):  
Surface Roughness ◽  
Experimental Investigations ◽  
Sensor Surface ◽  
Roughness Measurement ◽  
Surface Alignment ◽  
Evaluation Approach ◽  
Speckle Patterns ◽  
Speed Up ◽  
Scattering Centre ◽  
Roughness Measurements

AbstractSurface light scattering enables contactless and fast measurements of surface roughness. A surface inclination alters the direction of the scattering beam and thus the measured surface roughness is calculated from the detected intensity distribution. Hence, an accurate sensor–surface alignment is necessary. In order to achieve tilt-independent roughness measurements, a model-based evaluation approach for polychromatic speckle patterns is presented. By evaluating the shape of the superposed speckles, which occur for polychromatic illumination, with regard to the distance to the scattering centre, surfaces with an Sa roughness value in the range of 0.8–3.2 μm are measurable. Experimental investigations demonstrate that the influence of a surface tilt up to ± 1.25° on the roughness measurement is reduced by 90%. As a result, the robustness of the polychromatic speckle roughness measurement is improved, which allows to speed up the adjustment of the measurement system or the surface sample, respectively.

scholarly journals A Novel Measurement Standard for Surface Roughness on Involute Gears

2021 ◽  
Vol 11 (21) ◽  
pp. 10303
Author(s):  
Felix Steinmeyer ◽  
Dorothee Hüser ◽  
Rudolf Meeß ◽  
Martin Stein
Keyword(s):  
Surface Roughness ◽  
Physical Measurement ◽  
Roughness Measurement ◽  
Measurement Standard ◽  
Coordinate Measurement ◽  
Measurement Systems ◽  
Planar Surfaces ◽  
Involute Gears ◽  
Material Measure ◽  
Roughness Measurements

Although manufacturers of coordinate measurement systems and gear measurement systems already provide instruments that enable an end-of-line-monitoring of the roughness properties of gears, the roughness measurement on gear flanks still lacks traceability with respect to the standardised SI-units. There is still a gap between well standardised roughness measurements on planar surfaces and gear measurements on involutes. This gap is bridged by a novel physical measurement standard (PMS), also referred to as material measure, for roughness measurements on involute gears that has been developed at the Physikalisch-Technische Bundesanstalt (PTB). The necessary transformations between the systems of roughness and gear measurements have been implemented. The measurement standard itself represents calibrated roughness values for the parameters Ra, Rz, Rq, Rk, Rpk and Rvk and Mr1 and Mr2. Furthermore, the PMS can be measured both with classic profilometers as well as gear measurement systems with integrated roughness probes.

Speckle patterns produced by an optical vortex and its application to surface roughness measurements

2017 ◽  
Vol 56 (2) ◽  
pp. 330 ◽  
Author(s):  
M. H. M. Passos ◽  
M. R. Lemos ◽  
S. R. Almeida ◽  
W. F. Balthazar ◽  
L. da Silva ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Optical Vortex ◽  
Speckle Patterns ◽  
Roughness Measurements

Comparison of Surface Roughness Measurement in Dichromatic Speckle Patterns with Autocorrelation Method

2011 ◽  
Vol 189-193 ◽  
pp. 680-683 ◽  
Author(s):  
Zong Heng Yuan ◽  
Yan Hua Zhang ◽  
Jian Wei Zhang ◽  
Ye Fan Ge
Keyword(s):  
Surface Roughness ◽  
Autocorrelation Function ◽  
Correlation Length ◽  
High Reliability ◽  
Laser Speckle ◽  
Roughness Measurement ◽  
Elongation Ratio ◽  
Surface Roughness Measurement ◽  
Speckle Patterns ◽  
Autocorrelation Method

Applying autocorrelation method to process laser speckle patterns, the relation between surface roughness and speckle elongation and correlation length of autocorrelation function can be obtained, and the measured surface roughness can be achieved based on this relation. One-dimension autocorrelation and two-dimension autocorrelation function are used, Moreover, surface roughness is evaluated by speckle elongation and correlation length of autocorrelation function. Aspect ratio of speckle granular represents speckle elongation ratio, which eliminates effects of speckle granular average size on measurement results compared to other methods using before. It has high reliability and efficiency in surface roughness measurement evaluation.

Analysis on Combination of Different Wavelengths in Surface Roughness Measurement by Polychromatic Laser Speckle Patterns

2011 ◽  
Vol 189-193 ◽  
pp. 1978-1981
Author(s):  
Jing Huang ◽  
Jian Wei Zhang ◽  
Yan Hua Zhang ◽  
Zong Heng Yuan
Keyword(s):  
Surface Roughness ◽  
Measurement Precision ◽  
Laser Speckle ◽  
Roughness Measurement ◽  
Elongation Ratio ◽  
Measuring Process ◽  
Speckle Field ◽  
Measuring Surface ◽  
Speckle Patterns ◽  
The Difference

Based on the method of polychromatic speckle autocorrelation measuring surface roughness, this paper discussed the influence of the combination of different wavelengths on speckle patterns and speckle elongation ratio when rough surface and polychromatic speckle patterns were simulated. The results show that the smaller the difference of wavelengths combination is, the further peak of the speckle elongation ratio is from the speckle field centre, for the same surface roughness. And the wider area of speckle elongation effects extends. Therefore, influence of combination of wavelengths on measurement precision should be taken into consideration during measuring process.

Surface Roughness Measurements of a Narrow Borehole — Development of Stylus with Cylindrical Mirror and Lensed Fiber

2014 ◽  
Vol 939 ◽  
pp. 491-498 ◽  
Author(s):  
Eiki Okuyama ◽  
Wataru Yoshinari ◽  
Yuichi Suzuki ◽  
Riku Yoshida ◽  
Ichiro Yoshida ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Optical Signal ◽  
Measurement Range ◽  
Roughness Measurement ◽  
Confined Spaces ◽  
Major Disadvantage ◽  
Measure Surface Roughness ◽  
Cylindrical Mirror ◽  
Surface Profiles ◽  
Roughness Measurements

In various industrial fields, it is frequently necessary to measure surface roughness in confined spaces such as boreholes and grooves. However, using a small stylus, the surface roughness of a narrow borehole can be directly measured only a few millimeters from its end; alternatively, destructive measurements must be performed. This major disadvantage of conventional stylus-based surface profilometers is mainly due to an inductive pick-up that is connected to the stylus used to detect the surface roughness. In this paper, we propose a novel surface roughness measurement sensor. To make the surface roughness sensor small, we used a stylus with a cylindrical mirror and a lensed fiber instead of a conventional inductive pick-up. The proposed sensor converts the signal obtained by measuring the surface roughness of a borehole into an optical signal, which is transferred outside the borehole by an optical fiber. Experimental results demonstrate that this system has a measurement range of 8 μm and a sensitivity of 19 nm. Surface profiles were measured by the proposed sensor and by a conventional surface profiler and the results were found to be very similar.

scholarly journals How levelling and scan line corrections ruin roughness measurement and how to prevent it

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
David Nečas ◽  
Miroslav Valtr ◽  
Petr Klapetek
Keyword(s):  
Thin Films ◽  
Surface Roughness ◽  
Material Science ◽  
Mean Square ◽  
Roughness Measurement ◽  
Force Microscopy ◽  
Atomic Force ◽  
Scan Line ◽  
Scale Roughness ◽  
Roughness Measurements

Abstract Surface roughness plays an important role in various fields of nanoscience and nanotechnology. However, the present practices in roughness measurements, typically based on some Atomic Force Microscopy measurements for nanometric roughness or optical or mechanical profilometry for larger scale roughness significantly bias the results. Such biased values are present in nearly all the papers dealing with surface parameters, in the areas of nanotechnology, thin films or material science. Surface roughness, most typically root mean square value of irregularities Sq is often used parameter that is used to control the technologies or to link the surface properties with other material functionality. The error in estimated values depends on the ratio between scan size and roughness correlation length and on the way how the data are processed and can easily be larger than 10% without us noting anything suspicious. Here we present a survey of how large is the problem, detailed analysis of its nature and suggest methods to predict the error in roughness measurements and possibly to correct them. We also present a guidance for choosing suitable scan area during the measurement.

Surface roughness measurements of vanadium-contaminated fluidized cracking catalysts by atomic force microscopy

1996 ◽  
Vol 54 ◽  
pp. 866-867
Author(s):  
H. Kinney ◽  
M.L. Occelli ◽  
S.A.C. Gould
Keyword(s):  
Surface Roughness ◽  
Zeolite Y ◽  
Atomic Level ◽  
Microporous Structure ◽  
Contact Mode ◽  
Force Microscopy ◽  
Atomic Force ◽  
Before And After ◽  
Roughness Measurements ◽  
Cracking Catalysts

For this study we have used a contact mode atomic force microscope (AFM) to study to topography of fluidized cracking catalysts (FCC), before and after contamination with 5% vanadium. We selected the AFM because of its ability to well characterize the surface roughness of materials down to the atomic level. It is believed that the cracking in the FCCs occurs mainly on the catalysts top 10-15 μm suggesting that the surface corrugation could play a key role in the FCCs microactivity properties. To test this hypothesis, we chose vanadium as a contaminate because this metal is capable of irreversibly destroying the FCC crystallinity as well as it microporous structure. In addition, we wanted to examine the extent to which steaming affects the vanadium contaminated FCC. Using the AFM, we measured the surface roughness of FCCs, before and after contamination and after steaming.We obtained our FCC (GRZ-1) from Davison. The FCC is generated so that it contains and estimated 35% rare earth exchaged zeolite Y, 50% kaolin and 15% binder.

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