NDE/NDT -Optical Coherence Tomography News

Articles in category: NDE/NDT

1-24 of 138 1 2 3 4 5 6 »
1. Optical coherence tomography for non-destructive analysis of coatings in pharmaceutical tablets
  
  Explore Conference Proceedings May 28 2013 NDE/NDT
  
  Tablet coating is a common pharmaceutical technique to apply a thin continuous layer of solid on the top of a tablet or a granule containing active pharmaceutical ingredients (APIs). Coating thickness and homogeneity are critical parameters regarding the drug release rate, and consequently a direct or indirect monitoring strategy of these critical process parameters is essential. With the aid of Optical Coherence Tomography (OCT) it is not only possible to measure the absolute coating thickness, but also to detect inhomogeneities in the coating or substrate material. In this work the possible application of OCT as in-line method for monitoring pharmaceutical ...
  Read Full Article
  
  Comment
  
  Mentions: Michael Leitner RECENDT
2. Full field optical coherence microscopy for material testing: contrast enhancement and dynamic process monitoring
  
  Explore Conference Proceedings May 28 2013 NDE/NDT
  
  We illustrate the abilities of an advanced full-field optical coherence microscope (FF-OCM) setup for characterization of technical materials with internal micro-structures and present this technique also for dynamic process monitoring, as strain-stress tests. Additionally we briefly illustrate the potential of image processing in context of the chosen applications. Furthermore, contrast modification techniques based on Fourier plane filtering are discussed.
  Read Full Article
  
  Comment
  
  Mentions: David Stifter Bettina Heise Stefan E. Schausberger
3. Accurate prediction of collapse temperature using optical coherence tomography-based freeze-drying microscopy
  
  Explore Wiley Online Library May 19 2013 NDE/NDT , Other Non-Medical
  
  The objective of this study was to assess the feasibility of developing and applying a laboratory tool that can provide three-dimensional product structural information during freeze-drying and which can accurately characterize the collapse temperature ( T c ) of pharmaceutical formulations designed for freeze-drying. A single-vial freeze dryer coupled with optical coherence tomography freeze-drying microscopy (OCT–FDM) was developed to investigate the structure and T c of formulations in pharmaceutically relevant products containers (i.e., freeze-drying in vials). OCT–FDM was used to measure the T c and eutectic melt of three formulations in freeze-drying vials. The T c as measured by ...
  Read Full Article
  
  Comment
  
  Mentions: Daniel X. Hammer Physical Sciences Incorporated University of Connecticut
4. Film thickness measurement and defect inspection using optical coherence tomography
  
  Explore ScienceDirect May 13 2013 NDE/NDT
  
  An optical sensing technology based on optical coherence tomography is presented for film thickness measurement and defect inspection. In order to improve the imaging quality, a simple interference spectrum processing procedure is proposed to eliminate the DC and the autocorrelation noise. With the proposed method, we obtain high quality one-dimensional depth and two-dimensional cross-sectional images of the films. Then, the thickness and the defect information of the film can be obtained from the acquired images. The experiment result demonstrates that this nondestructive imaging technique is applicable for measuring film thickness and inspecting defects.
  Read Full Article
  
  Comment
  
  Mentions: Shanghai Jiao Tong University
5. Measurement of surface acoustic wave in soft material using swept-source optical coherence tomography
  
  Explore Linking to Scitation Content May 10 2013 NDE/NDT
  
  In endoscopic elastography, it is needed to observe small area with high spatial resolution. Optical coherence tomography (OCT) is one of the candidate imaging methods, which has the depth resolution of several 10 μm. In this study, we try to find the propagation velocity of surface acoustic wave (SAW) using a swept-source OCT (SS-OCT). The depth scanning rate in the SS-OCT is rather fast, which is determined by the wavelength sweep of the light source as fast as 20–100 kHz. However, on the other hand, the lateral scanning is limited up to 100 times per second, since it is ...
  Read Full Article
  
  Comment
6. Optical coherence tomography for vulnerability assessment of sandstone
  
  Explore opticsinfobase.org May 7 2013 NDE/NDT , Other Non-Medical
  
  Sandstone is an important cultural heritage material, in both architectural and natural settings, such as neolithic rock art panels. The majority of deterioration effects in porous materials such as sandstone are influenced by the presence and movement of water through the material. The presence of water within the porous network of a material results in changes in the optical coherence tomography signal intensity that can be used to monitor the wetting front of water penetration of dry porous materials at various depths. The technique is able to detect wetting front velocities from 1 cm s − 1 to 10 − 6 cm ...
  Read Full Article
  
  Comment
  
  Mentions: Nottingham Trent University Haida Liang
7. Feature Of The Week 4/28/13: King Abdullah University of Science and Technology Investigates Online Monitoring of Printed Electronics by SD-OCT
  
  Explore Optical Coherence Tomography News Apr 28 2013 NDE/NDT
  
  Printing technology is now being utilized to fabricate electronics and other active and passive devices and structures. Rotary printing techniques such as rotogravure, rotary screen, and flexography have been advantageous due to their ability to integrate with other rotary techniques to form what we refer to as Roll-to-Roll (R2R) process. In a R2R process, a roll of the base material (referred to as substrate) is unwined, functional materials printed on top of the substrate to form the needed structures or device, dried and rewined back to roll, or cut into individual devices. Most of current characterization of printed devices is ...
  Read Full Article
  
  Comment
  
  Mentions: Erkki Alarousu Ahmed AlSaggaf Ghassan E. Jabbour
8. Optical Coherence Tomography Enabling Non Destructive Metrology of Layered Polymeric GRIN Material
  
  Explore Nature Publishing Group Apr 24 2013 NDE/NDT , Other Non-Medical
  
  Gradient Refractive INdex (GRIN) optical components have historically fallen short of theoretical expectations. A recent breakthrough is the manufacturing of nanolayered spherical GRIN (S-GRIN) polymer optical elements, where the construction method yields refractive index gradients that exceed 0.08. Here we report on the application of optical coherence tomography (OCT), including micron-class axial and lateral resolution advances, as effective, innovative methods for performing nondestructive diagnostic metrology on S-GRIN. We show that OCT can be used to visualize and quantify characteristics of the material throughout the manufacturing process. Specifically, internal film structure may be revealed and data are processed to extract ...
  Read Full Article
  
  Comment
  
  Mentions: University of Rochester Kye-Sung Lee Panomsak Meemon
9. Measurement Technique Offers a Way of Improving Optical Lens Making
  
  Explore University of Rochester Apr 23 2013 NDE/NDT , Other Non-Medical
  
  Researchers at the University of Rochester have applied a sophisticated imaging technique to obtain the first 3D, high-resolution pictures of a recently developed type of optical lenses. They say that using Optical Coherence Tomography (OCT) during the manufacturing process allows them to significantly improve the quality of these new and promising lenses.
  Read Full Article
  
  Comment
  
  Mentions: University of Rochester Kye-Sung Lee Panomsak Meemon
10. 3D animation of optical coherence tomography of GRIN sheet
  
  Explore YouTube Apr 23 2013 NDE/NDT
  
  The University of Rochester team scanned a Gradient in Refractive Index (GRIN) sheet using Optical Coherence Tomography in order to show the structure of layers that make up the material. The technique allows the internal structure of the optical material to be understood without disturbing the material.
  Read Full Article
  
  Comment
  
  Mentions: University of Rochester Jannick P. Rolland
11. A 3D edge detection technique for surface extraction in computed tomography for dimensional metrology applications
  
  Explore ScienceDirect Apr 20 2013 NDE/NDT , Other Non-Medical
  
  Many factors influence the measurement uncertainty when using computed tomography for dimensional metrology applications. One of the most critical steps is the surface extraction phase. An incorrect determination of the surface may significantly increase the measurement uncertainty. This paper presents an edge detection method for the surface extraction based on a 3D Canny algorithm with sub-voxel resolution. The advantages of this method are shown in comparison with the most commonly used technique nowadays, i.e. the local threshold definition. Both methods are applied to reference standards and industrial parts and the comparison of the uncertainties obtained by both methods is ...
  Read Full Article
  
  Comment
  
  Mentions: Technical University of Denmark (DTU) Shahab Chitchian Santiago Jiménez-Valero
12. Dr. Michael Leitner will Give Webcast on Non-Medical Applications of OCT April 11th, 2013
  
  Explore BioOptics World Apr 2 2013 NDE/NDT
  
  In this webcast, Dr. Michael Leitner, head of the optical coherence tomography group at RECENDT - Research Center for Non Destructive Testing GmbH (Linz, Austria) discusses the application of OCT as a tool for microstructure analysis, device characterization, and quality control in materials science and industry.
  Read Full Article
  
  Comment
  
  Mentions: Michael Leitner RECENDT
13. Online monitoring of printed electronics by Spectral-Domain Optical Coherence Tomography
  
  Explore Nature Publishing Group Apr 1 2013 NDE/NDT
  
  Spectral-Domain Optical Coherence Tomography (SD-OCT) is an optical method capable of 3D imaging of object's internal structure with micron-scale resolution. Modern SD-OCT tools offer the speed capable of online monitoring of printed devices. This paper demonstrates the use of SD-OCT in a simulated roll-to-roll (R2R) process through monitoring some structural properties of moving screen printed interdigitated electrodes. It is shown that structural properties can be resolved for speeds up to ca. 1 m/min, which is the first step towards application of this method in real manufacturing processes, including roll-to-roll (R2R) printing.
  Read Full Article
  
  Comment
  
  Mentions: Erkki Alarousu Ahmed AlSaggaf Ghassan E. Jabbour
14. Signal processing in optical coherence tomography for aerospace material characterization
  
  Explore SPIE | Journal Mar 10 2013 NDE/NDT
  
  Based on a customized time-domain optical coherence tomography (OCT) system, a series of signal processing approaches have been designed and reviewed. To improve demodulation accuracy and image quality, demodulation approaches such as median filter, Hilbert transform, and envelope detector were investigated with simulated as well as experimental data. Without noise, the Hilbert transform has the best performance, but after considering the narrow-band noise in the modulated signal, the envelope detector was selected as the ideal demodulation technique. To reduce noise and enhance image contrast, digital signal processing techniques such as a bandpass filtering and two-dimensional median filtering were applied before ...
  Read Full Article
  
  Comment
  
  Mentions: Delft University of Technology Roger M. Groves
15. Feature Of The Week 3/10/13: Optical Coherence Tomography for Apple Surface Structure Evaluation
  
  Explore Optical Coherence Tomography News Mar 10 2013 NDE/NDT , Other Non-Medical
  
  Worldwide a lot of effort is invested in delivering fruit of the highest quality to the consumer. This means that the fruit should look good, taste good and preserve these properties for a sufficiently long period of time after harvest in order for the fruit to be of commercial value. Of course many aspects need to be considered, but here we will focus on the function of the peel. The first thing that meets the eye of the consumer is the peel of the fruit, and in many cases this is the only quality criterion that the consumer uses to ...
  Read Full Article
  
  Comment
  
  Mentions: K. U. Leuven Michael Leitner RECENDT
16. High-precision, high-accuracy ultralong-range swept-source optical coherence tomography using vertical cavity surface emitting laser light source
  
  Explore opticsinfobase.org Feb 21 2013 NDE/NDT
  
  We demonstrate ultralong-range swept-source optical coherence tomography (OCT) imaging using vertical cavity surface emitting laser technology. The ability to adjust laser parameters and high-speed acquisition enables imaging ranges from a few centimeters up to meters using the same instrument. We discuss the challenges of long-range OCT imaging. In vivohuman-eye imaging and optical component characterization are presented. The precision and accuracy of OCT-based measurements are assessed and are important for ocular biometry and reproducible intraocular distance measurement before cataract surgery. Additionally, meter-range measurement of fiber length and multicentimeter-range imaging are reported. 3D visualization supports a class of industrial imaging applications ...
  Read Full Article
  
  Comment
  
  Mentions: Massachusetts Institute of Technology James G. Fujimoto Thorlabs
17. First Symposium on OCT for Non-Destructive Testing (OCT4NT) held in Linz Austria a Success
  
  Explore Optical Coherence Tomography News Feb 21 2013 NDE/NDT
  
  On the 13 th and 14 th of February 2013 the RECENDT hosted the First International Symposium on Optical Coherence Tomography for Non-Destructive Testing – OCT4NDT ( www.oct4ndt.com ) in Linz, Austria. The event was attended by around 65 researchers and company delegates from all over the world (covering 18 different countries on five different continents). During 27 talks and a poster session the different research groups had the possibility to present their work in front of an interested audience. The OCT4NDT provided a platform for the discussion of new ideas and applications and for establishing new future collaborations. Therefore the ...
  Read Full Article
  
  Comment
  
  Mentions: Michael Leitner RECENDT
18. Feature Of The Week 2/10/13: Cranfield University Researchers Investigate Using OCT For Adhesive Cure Monitoring
  
  Explore Optical Coherence Tomography News Feb 9 2013 NDE/NDT
  
  Monitoring the progress of cure in an adhesive enables changes in behaviour to be studied under differing conditions of temperature, humidity or illumination, and allows the importance of other factors, such as variability between production batches, volume of adhesive or altered composition due to aging, to be assessed. Detailed knowledge of the cure process minimises the time that must be allowed before further processing. For exothermic reactions, it is possible to track progress via measurement of the temperature at one or more positions within the cure region. More generally, acoustic sensors, which detect the material modulus, and dielectric measurement methods ...
  Read Full Article
  
  Comment
  
  Mentions: Cranfield University Ralph P. Tatam Helen D. Ford
19. Announcing The First International Symposium on Optical Coherence Tomography for Non-Destructive Testing (OCT4NDT) February 13-14, 2013 Linz Austria
  
  Explore Optical Coherence Tomography News Jan 23 2013 NDE/NDT
  
  Optical coherence tomography (OCT) applications in the field of non-destructive testing (NDT) have grown immensely over the past few years. In order to pave the ground for a new OCT for NDT community we are pleased to announce the First International Symposium on OCT4NDT! The symposium is intended as a get-together for people working in this field and aims at initiating new ideas and projects. . For more information please click Here .
  Read Full Article
  
  Comment
  
  Mentions: Michael Leitner RECENDT
20. Spatially-resolved volume monitoring of adhesive cure using correlated-image optical coherence tomography
  
  Explore ScienceDirect Dec 10 2012 NDE/NDT
  
  Cross-correlation of optical coherence tomography (OCT 1 ) images has been applied to internal imaging of PVA and two-part epoxy adhesives during cure, providing information on relative viscosity at different positions within the sample volume. Spatial resolution of a few micrometres is obtained in the original OCT images, and a few tens of micrometres in the correlation images, enabling the progress of cure to be mapped in fine detail within a small cure volume. Evidence of phase separation is seen in the OCT and correlation images of a partially-cured PVA emulsion. Mixing structure and regions of poor cure can be observed ...
  Read Full Article
  
  Comment
  
  Mentions: Cranfield University Ralph P. Tatam Helen D. Ford
21. Imaging Internal Flows in a Drying Sessile Polymer Dispersion Drop using Spectral Radar Optical Coherence Tomography (SR-OCT)
  
  Explore ScienceDirect Dec 10 2012 NDE/NDT
  
  In this work, we present the visualization of the internal flows in a drying sessile polymer dispersion drop on hydrophilic and hydrophobic surfaces with Spectral Radar Optical Coherence Tomography (SR-OCT). We have found that surface features such as the initial contact angle and pinning of the contact line, play a crucial role on the flow direction and final shape of the dried drop. Moreover, imaging through selection of vertical slices using optical coherence tomography offers a feasible alternative compared to imaging through selection of narrow horizontal slices using confocal microscopy for turbid, barely transparent fluids.
  Read Full Article
  
  Comment
  
  Mentions: Nottingham Trent University Haida Liang
22. Spectral-Domain Optical Coherence Tomography for Material Detection
  
  Explore Scientific.Net Dec 6 2012 NDE/NDT
  
  Optical coherence tomography is a non-invasive cross-sectional imaging technology for inhomogeneous samples. Spectral-domain optical coherence tomography is introduced to measure film and Silicon dovetail groove in this paper. A novel method is used to deal with the interference spectrum to improve the quality of the two-dimensional cross-sectional image. The experimental result shows the microstructure of the two samples can be clearly seen as expected. From the visualized two-dimensional cross-sectional imaging, the film thickness and the dimension of the Silicon dovetail groove are obtained with this technique. It is experimentally demonstrated that this system is useful for imaging the microstructure of ...
  Read Full Article
  
  Comment
  
  Mentions: Shanghai Jiao Tong University
23. Full-field optical coherence microscopy with Riesz transform-based demodulation for dynamic imaging
  
  Explore opticsinfobase.org Nov 29 2012 Microscopy , NDE/NDT
  
  We present dynamic full-field optical coherence microscope imaging using a scientific complementary metal oxide semiconductor camera in conjunction with a demodulation scheme based on the Riesz transform and monogenic signals. The potential of our approach is verified by a comparison with conventional phase-stepping as well as with an analytic reconstruction method and finally exemplified for dynamic mechanical testing of a polymer/fiber composite structure.
  Read Full Article
  
  Comment
  
  Mentions: David Stifter Bettina Heise Stefan E. Schausberger
24. OCT for industrial applications
  
  Explore Conference Proceedings Nov 24 2012 NDE/NDT , Other Non-Medical
  
  Optical coherence tomography (OCT), as an interferometric method, has been studied as a distance ranger. As a technology capable of producing high-resolution, depth-resolved images of biological tissue, OCT had been widely used for the application of ophthalmology and has been commercialized in the market today. Enlightened by the emerging research interest in biomedical domain, the applications of OCT in industrial inspection were rejuvenated by a few groups to explore its potential for characterizing new materials, imaging or inspecting industrial parts as a service solution[3]. Benefiting from novel photonics components and devices, the industrial application of the older concepts in ...
  Read Full Article
  
  Comment
  
  Mentions: Michelson Diagnostics Thorlabs
1-24 of 138 1 2 3 4 5 6 »