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Hussam Muhamedsalih

Bio: Hussam Muhamedsalih is an academic researcher from University of Huddersfield. The author has contributed to research in topics: Interferometry & Roll-to-roll processing. The author has an hindex of 9, co-authored 31 publications receiving 347 citations. Previous affiliations of Hussam Muhamedsalih include Engineering and Physical Sciences Research Council.

Papers
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Journal ArticleDOI
TL;DR: In this article, an optical interferometry system for fast areal surface measurement of microscale and nanoscale surfaces that are immune to environmental noise is presented. But the system can be used for online or in-process measurement on a shop floor.
Abstract: We introduce a new optical interferometry system for fast areal surface measurement of microscale and nanoscale surfaces that are immune to environmental noise. Wavelength scanning interferometry together with an acousto-optic tunable filtering technique is used to measure surfaces with large step heights. An active servo control system serves as a phase-compensating mechanism to eliminate the effects of environmental noise. The system can be used for online or in-process measurement on a shop floor. Measurement results from two step height standard samples and a structured surface of a semiconductor daughterboard are presented. In comparison with standard step height specimens, the system achieved nanometer measurement accuracy. The measurement results of the semiconductor daughterboard, under mechanical disturbance, showed that the system can withstand environmental noise.

117 citations

Journal ArticleDOI
TL;DR: The theoretical analysis and simulation study of wavelength scanning interferometry for transparent film measurement is discussed and experiments on thin film layers of Parylene N coated on a glass slide surface are studied and analyzed.
Abstract: A wavelength scanning interferometer for measuring the surface and thickness of a transparent film has been studied. A halogen light source combined with an acousto-optic tuneable filter is used to generate a sequence of filtered light in a Linnik interferometer, which leads to a sequence of interferograms captured by a CCD camera. When a transparent thin film is measured, the reflection signals from both the top and bottom surfaces of the film will interfere with the reference signal. At the same time, the multiple reflection signals between the two film surfaces will also interfere with each other. Effective separation of the interference signals from each other is the key to achieving a successful measurement. By performing a frequency-domain analysis, these interference signals can be separated. An optimized Fourier transform method is used in the analysis. Measurements of the top and bottom surface finishes of the film, as well as the film thickness map, have been achieved. The film needs to be more than 3 µm in optical path length, and must transparent with no absorption of light. The film’s refractive index needs to be known as a function of wavelength. In this paper, the theoretical analysis and simulation study of wavelength scanning interferometry for transparent film measurement is discussed. Experiments on thin film layers of Parylene N coated on a glass slide surface are studied and analyzed. Comparison study results with other contact and non-contact methods are also presented.

62 citations

Patent
14 Jun 2007
TL;DR: In this article, the authors describe a system in which a wavelength selector (5) selects a wavelength of a broadband light source (4), and a light director (BS1, BS2) directs light from the wavelength selector along a measurement path toward a region of a sample surface and along a reference path towards a reference surface.
Abstract: A wavelength selector (5) selects a wavelength of a broadband light source (4). A light director (BS1, BS2) directs light from the wavelength selector along a measurement path towards a region of a sample surface and along a reference path towards a reference surface,such that light reflected by the region of the sample surface and light reflected by the reference surface interfere to produce an interferogram. A controller (20) controls the wavelength selector to change the wavelength selected by the wavelength selector. A recorder (63) records successive images,each image representing the interferogram produced by a respective one of the wavelengths selected by the wavelength selector. A data processor (18, 180) processes the recorded images to produce at least one of a surface profile and a surface height map of at least a part of the sample surface. The reference path may be controlled to compensate for environmental effects such as vibration, thermal effects and air turbulence. The data processor may use a graphics processing unit to enable pixel data to be processed in parallel.

38 citations

Journal ArticleDOI
TL;DR: Comparison of four different algorithms to analyze the interference fringe pattern acquired from WSI is provided and it is demonstrated that the accuracy of measuring surface height varies from micrometer to nanometer value depending on the algorithm used to analyzed the captured interferograms.
Abstract: Wavelength scanning interferometry (WSI) can be used for surface measurement with discontinuous surface profiles by producing phase shifts without any mechanical scanning process. The choice of algorithms for the WSI to analyze the fringe pattern depends on the desired accuracy and computing speed. This paper provides comparison of four different algorithms to analyze the interference fringe pattern acquired from WSI. The mathematical description of these algorithms, their computing resolution, and speed are presented. Two step-height samples are measured using the WSI. Experimental results demonstrate that the accuracy of measuring surface height varies from micrometer to nanometer value depending on the algorithm used to analyze the captured interferograms.

27 citations

Journal ArticleDOI
TL;DR: In this article, the authors proposed a wavelength scanning interferometer (WSI) for micro and nano-scale areal surface measurement, which can measure large discontinuous surface profiles without phase ambiguity problems.

22 citations


Cited by
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Journal Article
TL;DR: In this article, a fast Fourier transform method of topography and interferometry is proposed to discriminate between elevation and depression of the object or wave-front form, which has not been possible by the fringe-contour generation techniques.
Abstract: A fast-Fourier-transform method of topography and interferometry is proposed. By computer processing of a noncontour type of fringe pattern, automatic discrimination is achieved between elevation and depression of the object or wave-front form, which has not been possible by the fringe-contour-generation techniques. The method has advantages over moire topography and conventional fringe-contour interferometry in both accuracy and sensitivity. Unlike fringe-scanning techniques, the method is easy to apply because it uses no moving components.

3,742 citations

Journal ArticleDOI
TL;DR: Error separation algorithms for removing machine tool errors, which is specially required in on-machine and in-process surface metrology, are overviewed, followed by a discussion on calibration and traceability.

232 citations

B.P. Jones1
05 Apr 1993
TL;DR: The British Standards Institution (BSI) is the body responsible for preparing British Standards as discussed by the authors, which provides the gateway for UK representation in European and International Standards Organizations (ESO).
Abstract: The British Standards Institution (BSI) is the body responsible for preparing British Standards. It provides the gateway for UK representation in European and International Standards Organizations. It is a nonprofit organization formed by subscribing members and committee members and incorporated by Royal Charter since 1929. Here, the author covers the work of BSI Committees which are concerned with electricity metering standards with particular emphasis on European standards.< >

151 citations

Journal ArticleDOI
TL;DR: This paper reviews recent developments of non-contact three-dimensional (3D) surface metrology using an active structured optical probe and discusses principles of each technology, and its advantageous characteristics as well as limitations.
Abstract: This paper reviews recent developments of non-contact three-dimensional (3D) surface metrology using an active structured optical probe. We focus primarily on those active non-contact 3D surface measurement techniques that could be applicable to the manufacturing industry. We discuss principles of each technology, and its advantageous characteristics as well as limitations. Towards the end, we discuss our perspectives on the current technological challenges in designing and implementing these methods in practical applications.

109 citations

Journal ArticleDOI
TL;DR: The stimulation results show that comparing with other experimental methods, the decision fusion method based on weighted D-S evidence theory has higher utilization efficiency and recognition rate.
Abstract: A weighted fusion method of D-S evidence theory in decision making is proposed to aim at the problem of lacking in the distribution of trust, data processing and precision in D-S evidential theory. The method of gesture recognition based on Kinect and sEMG signal are established. Weighted D-S evidence theory is used to fuse Kinect and sEMG signals and the simulation experiment is made respectively. The stimulation results show that comparing with other experimental methods, the decision fusion method based on weighted D-S evidence theory has higher utilization efficiency and recognition rate.

89 citations