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All Outputs (196)

Material standards design for minimum zone fitting of freeform optics (2019)
Presentation / Conference
Arezki, Y., Lepretre, F., Psota, P., Su, R., Heikkinen, V., Zhang, X., …Nouira, H. (2019, June). Material standards design for minimum zone fitting of freeform optics. Paper presented at euspen’s 19th International Conference & Exhibition, Bilbao, Spain

Optical measurement of surface topographies with transparent coatings (2019)
Journal Article
Feng, X., Senin, N., Su, R., Ramasamy, S., & Leach, R. (2019). Optical measurement of surface topographies with transparent coatings. Optics and Lasers in Engineering, 121, 261-270. https://doi.org/10.1016/j.optlaseng.2019.04.018

Manufacturers nowadays have access to state-of-the-art areal surface topography measurement instruments that allow investigation of surface topography at unprecedented levels of detail and over a wide range of scales. However, high value-added produc... Read More about Optical measurement of surface topographies with transparent coatings.

Methodology for the development of in-line optical surface measuring instruments with a case study for additive surface finishing (2019)
Journal Article
Syam, W. P., Rybalcenko, K., Gaio, A., Crabtree, J., & Leach, R. K. (2019). Methodology for the development of in-line optical surface measuring instruments with a case study for additive surface finishing. Optics and Lasers in Engineering, 121, 271-288. https://doi.org/10.1016/j.optlaseng.2019.04.015

The productivity rate of a manufacturing process is limited by the speed of any measurement processes at the quality control stage. Fast and effective in-line measurements are required to overcome this limitation. Optical instruments are the most pro... Read More about Methodology for the development of in-line optical surface measuring instruments with a case study for additive surface finishing.

Lateral error compensation for stitching-free measurement with focus variation microscopy (2019)
Journal Article
Pérez, P., Syam, W. P., Antonio Albajez, J., Santolaria, J., & Leach, R. (2019). Lateral error compensation for stitching-free measurement with focus variation microscopy. Measurement Science and Technology, 30(6), Article 065002. https://doi.org/10.1088/1361-6501/ab046e

This paper proposes a practical methodology to quantify and compensate lateral errors for focus variation microscopy measurements without stitching. The main advantages of this new methodology are its fast and simple implementation using any uncalibr... Read More about Lateral error compensation for stitching-free measurement with focus variation microscopy.

Towards superresolution surface metrology: quantum estimation of angular and axial separations (2019)
Journal Article
Napoli, C., Piano, S., Leach, R., Adesso, G., & Tufarelli, T. (2019). Towards superresolution surface metrology: quantum estimation of angular and axial separations. Physical Review Letters, 122(14), Article 140505. https://doi.org/10.1103/physrevlett.122.140505

We investigate the localization of two incoherent point sources with arbitrary angular and axial separations in the paraxial approximation. By using quantum metrology techniques, we show that a simultaneous estimation of the two separations is achiev... Read More about Towards superresolution surface metrology: quantum estimation of angular and axial separations.

Residual flatness and scale calibration for a point autofocus surface topography measuring instrument (2019)
Journal Article
Maculotti, G., Feng, X., Su, R., Galetto, M., & Leach, R. K. (2019). Residual flatness and scale calibration for a point autofocus surface topography measuring instrument. Measurement Science and Technology, 30(7), https://doi.org/10.1088/1361-6501/ab188f

Point autofocus instruments are often used for measuring the surface topography of objects with complex geometry. Determining the metrological characteristics of the instrument is key to ensuring a traceable areal surface topography measurement. In t... Read More about Residual flatness and scale calibration for a point autofocus surface topography measuring instrument.

Assessment of surface topography modifications through feature-based registration of areal topography data (2019)
Journal Article
Moretti, M., Gambucci, G., Leach, R., & Senin, N. (2019). Assessment of surface topography modifications through feature-based registration of areal topography data. Surface Topography: Metrology and Properties, 7(2), https://doi.org/10.1088/2051-672X/ab152a

Surface topography modifications due to wear or other factors are usually investigated by visual and microscopic inspection, and – when quantitative assessment is required – through the computation of surface texture parameters. However, the current... Read More about Assessment of surface topography modifications through feature-based registration of areal topography data.

All-optical difference engine for in-process defect inspection for roll-to-roll printed electronics (2019)
Journal Article
Feng, X., Su, R., Happonen, T., Liu, J., & Leach, R. (2019). All-optical difference engine for in-process defect inspection for roll-to-roll printed electronics. Proceedings of SPIE, 11053, https://doi.org/10.1117/12.2511140

© 2019 SPIE. The increasing capabilities of roll-to-roll (R2R) printing processes present challenges for quality control, requiring inprocess inspection of large substrates with high resolution at high speed. In this paper, an all-optical difference... Read More about All-optical difference engine for in-process defect inspection for roll-to-roll printed electronics.

Mathematical approach to the validation of functional surface texture parameter software (2019)
Journal Article
Todhunter, L., Leach, R., Lawes, S., Harris, P., & Blateyron, F. (2019). Mathematical approach to the validation of functional surface texture parameter software. Surface Topography: Metrology and Properties, 7(1), Article 015020. https://doi.org/10.1088/2051-672X/ab07ca

A new method for performance validation of surface texture parameter calculation software is introduced, focussing on functional surface texture parameters. Material ratio curves are defined algebraically and used to calculate functional surface text... Read More about Mathematical approach to the validation of functional surface texture parameter software.

Resolution enhancement for topography measurement of high-dynamic-range surfaces via image fusion (2018)
Journal Article
Wang, J., Su, R., Leach, R., Lu, W., Zhou, L., & Jiang, X. (2018). Resolution enhancement for topography measurement of high-dynamic-range surfaces via image fusion. Optics Express, 26(26), 34805-34819. https://doi.org/10.1364/OE.26.034805

In this paper, we introduce a method and algorithm for resolution enhancement of low-resolution surface topography data by fusing it with corresponding high-resolution intensity images. This fusion is carried out by linking the three-dimensional topo... Read More about Resolution enhancement for topography measurement of high-dynamic-range surfaces via image fusion.

Imaging beyond the fundamental slope limit in surface metrology using fluorophore-aided scattering microscopy (2018)
Presentation / Conference
Liu, J., Liu, C., Li, L., Su, R., & Leach, R. (2018, November). Imaging beyond the fundamental slope limit in surface metrology using fluorophore-aided scattering microscopy. Paper presented at Special Interest Group Meeting: Structured & Freeform Surfaces

Topography measurement for smooth surfaces with high slopes, e.g. freeform optics, is a challenging task for optical measuring instruments as the light reflected by the tilted surface cannot be sufficiently collected by the objective, resulting in lo... Read More about Imaging beyond the fundamental slope limit in surface metrology using fluorophore-aided scattering microscopy.

Areal topography measurement of metal additive surfaces using focus variation microscopy (2018)
Journal Article
Newton, L., Senin, N., Gomez, C., Danzl, R., Helmli, F., Blunt, L., & Leach, R. (2019). Areal topography measurement of metal additive surfaces using focus variation microscopy. Additive Manufacturing, 25, 365-389. https://doi.org/10.1016/j.addma.2018.11.013

In this work, the performance of a focus variation instrument for measurement of areal topography of metal additive surfaces was investigated. Samples were produced using both laser and electron beam powder bed fusion processes with some of the most... Read More about Areal topography measurement of metal additive surfaces using focus variation microscopy.

Mechanical vibration bandgaps in surface-based lattices (2018)
Journal Article
Elmadih, W., Syam, W. P., Maskery, I., Chronopoulos, D., & Leach, R. (2019). Mechanical vibration bandgaps in surface-based lattices. Additive Manufacturing, 25, 421-429. https://doi.org/10.1016/j.addma.2018.11.011

In this paper, the phonon dispersion curves of several surface-based lattices are examined, and their energy transmission spectra, along with the corresponding bandgaps are identified. We demonstrate that these bandgaps may be controlled, or tuned, t... Read More about Mechanical vibration bandgaps in surface-based lattices.

Rapid tracking of extrinsic projector parameters in fringe projection using machine learning (2018)
Journal Article
Stavroulakis, P., Chen, S., Delorme, C., Bointon, P., Tzimiropoulos, G., & Leach, R. (2019). Rapid tracking of extrinsic projector parameters in fringe projection using machine learning. Optics and Lasers in Engineering, 114, 7-14. https://doi.org/10.1016/j.optlaseng.2018.08.018

In this work, we propose to enable the angular re-orientation of a projector within a fringe projection system in real-time without the need for re-calibrating the system. The estimation of the extrinsic orientation parameters of the projector is per... Read More about Rapid tracking of extrinsic projector parameters in fringe projection using machine learning.

Verification of a rigorous 2D model of rough surface scattering (2018)
Conference Proceeding
Thomas, M., Leach, R., Nikolaev, N., Widjanarko, T., Senin, N., Aryan, H., & Coupland, J. (2018). Verification of a rigorous 2D model of rough surface scattering.

A rigorous two-dimensional (2D) model of electromagnetic surface scatter has been developed, based on a boundary element method (BEM) established by Simonsen [1]. Simulated far-field scatter is compared to that measured from a laser scatterometer for... Read More about Verification of a rigorous 2D model of rough surface scattering.