Events

X-ray Technology and Phase Contrast Imaging Workshop & Roundtable Discussion

Date: 02 Nov 2011 - 02 Nov 2011

Venue: SIMTech Auditorium, Level 3, Tower Block

Introduction
X-ray phase contrast imaging (PCI) has an inherent potential for a significant dose reduction combined with an image quality enhancement in X-ray radiography as well as in computed tomography (CT) measurements. Not only the absorption of X-rays in the measurement object is probed, as in classical X-ray measurements, but also the difference in velocity X-rays undergo while travelling through an inhomogeneous object. The resulting (small) wavefront deviations can be measured by interferometry, in a Talbot interferometer set-up. X-rays do not need to be absorbed in the object at all in PCI, which opens the possibility to optimize X-ray measurements with respect to image quality and radiation dose at the same time, which is not possible for classical X-ray imaging.

Though the potential of PCI has been been demonstrated experimentally, the realisation for specific applications is not at all straight forward. Firstly, how to reveal and interpret features obtained by the new modality is unclear and not well established. Secondly, industrial applications set very stringent requirements related to the size of the field-of-view, the mechanical stability and/or the flexibility, measurement time and sample throughput. The most crucial issue relates to the X-ray energy. In order to achieve sufficient sample transmission, many applications require relatively high energies which impose significant challenges on the instrumentation and its fabrication.

This workshop is focused on the latest developments in X-ray technologies for phase contrast X-ray imaging in two and three dimensions. Commercial solutions based on these technologies have widespread applications in the aerospace, precision engineering, electronics and biomedical industries. These technologies play an important role in inspecting, measuring and modeling internal structures for product development, quality assurance, and failure analysis.

The workshop will also cover the latest research and technology developments at SIMTech and elsewhere in Singapore in the related areas of computed tomography, X-ray characterisation and image processing.

Following on from the technical presentations, a round table discussion session will provide an opportunity for attendees to share their needs for X-ray based industrial inspection and measurement, to identify common areas of interest, to propose topics for future research and development and to gain a better understanding of the applicability of X-ray technology.
 
Programme
8.45am    Registration

9.00am    Introduction to SIMTech and Workshop by Dr Zhang Ying, Director, Manufacturing Automation Division, SIMTech

9.15am    Introduction to CSEM and its activities by Dr Rolf Kaufmann, Leading Scientist, CSEM

9.30am     X-ray and Photonic Technologies of CSEM by Dr Rolf Kaufmann
                 CSEM has long track-record in photonic technologies. With different teams it is currently active in the development of CMOS image sensors, 
                 customised optics and electro-optical systems, monolithic near-infrared and X-ray sensors, miniaturised X-ray sources, phase-contrast x-ray 
                 imaging and in HR-XRD. Recent achievements in all these topics will be presented. Possible collaboration- and application ideas are highly 
                 welcome and can be discussed during the talk. 

10.30am  Coffee Break

11.00am   Phase-contrast X-ray Imaging by Dr Rolf Kaufmann
                 Phase contrast X-ray imaging is an established technology at many synchrotrons in the world. With the grating based Talbot-Lau interferometer it
                 is now possible to use this technology also with incoherent commercial X-ray tubes, which opens numerous possibilities for applications in 
                 health, NDT and security. The principle of the Talbot-Lau interferometer will be explained and potential applications discussed.

12.30pm  Lunch

1.30pm     Phase-contrast Imaging and Tomography by Dr Krzysztof Banas, Research Scientist, Singapore Synchrotron Light Source (SSLS)
                 Phase Contrast Imaging and Tomography (PCIT) beamline features a white beam of X-rays with a cross-section of 20×8 mm2 and the energy 
                 range of about 4 to 12 keV. After passing through the sample X-rays are converted to visible light by a CdWO4 scintillator and deflected by a mirror 
                 into high-sensitivity CCD camera. Imaging suite X-TRACT is typically used for pre-processing and evaluation of phase contrast enhanced 
                 projections. In this talk selected research topics done at PCIT beamline will be presented.

1.45pm     Applying Pseudolocal Tomography on Phase Enhancement Imaging by Dr Vo Trong Nghia, Researcher, SSLS
                 Pseudolocal tomography is one of the local tomography methods that enable to reconstruct 3D structure of objects even bigger than the beam
                 size. This locality reconstruction is very appropriate for tomography at synchrotron light source because of its limited beam size problem. However, 
                 what we reconstruct is not the spatial density of the object, but the magnitude of sharp density variations. This feature is very useful in applications 
                 where one is more interested in enhancing the visualization of discontinuity structures of samples. The initial results of applying pseudolocal 
                 tomography show that it can reconstruct 3D imaging of object with the superior quality of high contrast and reducing noise. In addition to, it can 
                 gain the advantage of phase enhancement of coherent light source. In this talk, we present the background theory of pseudolocal tomography and 
                 some of its practical applications.

2.00pm     NanoX Technology Laminography & CT Systems by Mr Michael Soeding, Managing Director, Nanox Technology Pte Ltd
                 The nX2000 platform represents a cost efficient and flexible X-ray inspection solution to accommodate various 3D methodologies. The smart 
                 implementation supports 3D Laminography and 3D Computed Tomography without using highly sophisticated and cost intensive mechanical 
                 solutions. The open platform is already prepared for future expansion into oblique and helix CT methodologies.

2.30pm     SIMTech High Energy System Development by Dr Andy Malcolm, Scientist III, SIMTech
                 This presentation will provide details of SIMTech’s on-going development of a dual-source (225/450 kV) reconfigurable universal X-ray CT system
                 for samples up to 1m3 in size. The potential scientific and industrial impact will be discussed. Target applications from the precision  
                 engineering,  oil and gas, and aerospace industry sectors will be presented.

2.45pm    X-ray CT Reconstruction Techniques, Dr Liu Tong, Senior Research Engineer III, SIMTech

3.00pm     XRD & XRF Characterisation by Dr Sim Lay May, Senior Research Engineer II SIMTech 
                 A general introduction to X-ray Diffractometry (XRD) and X-ray Fluorescence is provided. It explains simply the principles and its applications of 
                 both these methods. This presentation is intended to provide a global overview of the XRD and XRF while describing how they can be used for 
                 various material characterization applications.

3.15pm    3D Imaging for X-ray by Dr Xu Jian, Principal Research Engineer II, SIMTech
                In this presentation we report our recent progresses in automatic processing of volumetric CT data for semiconductor applications. These include:
                • Segmentation of layer of interest for multi-layer sandwich structures such as PCB, LTCC and multi-stacked dies
                • 3D wire loop tracing for a sealed wirebond device for sagging wire detection
                • Leadframe warpage inspection
                For layer segmentation, we propose a RDHT method (Reduced Dimension Hough Transformation) for automatic planar structure detection. 
                Instead of segmenting internal surfaces at voxel level, directional features are extracted in 3D space whereby the likehood of any planar
                structure is associated with the number of features on a specific plane.  We accumulate 3D features in three one dimensional accumulators plus 
                one verification accumulator to reduce Hough space searching from 3D to 1D to achieve high speed. We use a low cost X-ray CT system to scan a 
                sealed wirebond device and processed slices at present of large amount of artifacts for 3D wire loop inspection.  First 3D primitives are detected in
                randomized planes with a subpixel transition detection algorithm. Then potential wire centroids are calculated using enhanced generalized
                cylinder model to minimize interferences from beam-hardening. Tracing of wires are performed in a projection image. Wire start and end points are
                detected and paired using directional histogram analysis. Wire loop heights can be derived from the traced wires. Leadframe warpage may cause 
                seriously quality issue for devices like BGA, TSV whereby coplanarity of all contact points are required. We demonstrate that leadframe can be 
                detected with the help of a Chevyshev polynomial with selectable 3x3 or 4x4 nodes. In this way any point’s 3D coordinate on the leadframe can be 
                calculated. Max warpage is derived by evaluating the deviation of all leadframe points from a best fit plane.

3.30pm   Coffee Break

3.45pm   Roundtable Discussion Session

5.00pm   Review and Wrap-up

5.30pm   End

About the Speakers
Dr Rolf Kaufmann is the Deputy Section Head and Project-Manager in the Photonics Division of the Centre Suisse d'Electronique et de Microtechnique SA (CSEM) in Zurich. After his PhD at the Paul Scherrer Institute and at CERN, he joined CSEM where he worked in analogue chip design and in CMOS process optimisations. He was significantly involved in building up the X-ray imaging activities at CSEM, which he technically coordinates today.

Dr Krzysztof Banas completed his Ph.D. in 2002 at Jagiellonian University (Krakow, Poland) on nuclear magnetic resonance (NMR) relaxometry research on paper ageing processes. He held postdoctoral research position at University of Leipzig (Leipzig, Germany).  He contributed to the development of novel diffusion-based performance optimisation of micro-porous membranes and particle. Since 2007, he has been a research scientist in Singapore Synchrotron Light Source at National University of Singapore. His research activities involve the search for synergetic approach of imaging and spectroscopy of various systems by using synchrotron source and statistical evaluation of the results. 

Mr Michael Soeding founded nanoX Technology in 2010 and is currently the CEO and Managing Director of the company. Before, he had been the Managing Director within the Schmidt Electronics Group of MacroScience Technology, specialized in 3D inline and offline X-ray systems, and GigaWaveTech, specialized in wireless communication modules. Prior to joining Schmidt Electronics, he was the Vice –President and Director of Infineon Technologies Asia Pacific Pte Ltd. Mr. Soeding has graduated with a Master Degree (Dipl.-Ingenieur) of Electronic Engineering from the University RWTH Aachen in Germany in 1984. He has extensive international exposure covering Germany, Japan and Hong Kong before being stationed in Singapore since 1997.

Dr Andrew Malcolm is a research scientist with the Precision Measurements Group within SIMTech. He received his PhD from Liverpool John Moores University in the area of image analysis for precision measurement applied to engineering components. He has over 20 years of experience in the areas of machine vision, image processing and industrial inspection. His current research activities are focused on X-ray computed tomography for dimensional measurement and non-destructive testing.

Dr Sim Lay May is a Senior Research Engineer at SIMTech. She graduated with a PhD from Loughborough University in the research area of designing, manufacturing and testing of smart composite beams with EFPI strain sensor for damage detection. She has worked in the areas of materials science, material characterization and failure analysis for more than 7 years, and has been extensively involved in industrial related projects for failure analysis and inspection both destructive and non-destructive. Her research interest areas mainly involve X-ray materials characterization and other non-destructive testing methods.

Dr Xu Jian received his Doctor of Engineering degree from Erlangen-Nuremberg University, Germany in 1992. Heis currently a principle research engineer at SIMTech. His research interests include 3D machine vision using photogrammetry and stereo vision, camera calibration, sensor fusion, subpixeling image processing, statistical image processing, and volumetric  CT image segmentation, registration, inspection and measurement.

Registration
To reserve a seat for this non-chargeable event, please click here.

Who Should Attend
• Professionals involved in manufacturing precision engineering components and electronic devices
• Process engineers of device manufacturers
• Industry professionals, R&D managers, researchers and academic staff from the automotive, telecommunications, electrical, electronics & mechanical engineering, medical & healthcare, household & consumer goods and aerospace industries

Contact Us
For technical enquiries: Dr Andy Malcolm, Email: andy@SIMTech.a-star.edu.sg