scholarly journals Three-Dimensional Super-Resolution Morphology by Near-Field Assisted White-Light Interferometry

2016 ◽  
Vol 6 (1) ◽  
Author(s):  
Feifei Wang ◽  
Lianqing Liu ◽  
Peng Yu ◽  
Zhu Liu ◽  
Haibo Yu ◽  
...  
Keyword(s):  
White Light ◽  
Near Field ◽  
Three Dimensional ◽  
Super Resolution ◽  
White Light Interferometry

Using White Light Interferometry for Mesoscale Part Inspection

2003 ◽  
Author(s):  
K. Meghan Shilling ◽  
Thomas R. Kurfess
Keyword(s):  
White Light ◽  
Three Dimensional ◽  
File Systems ◽  
Bottom Surface ◽  
White Light Interferometry ◽  
Planar Surfaces ◽  
Coordinate Metrology ◽  
Data Points ◽  
Part Inspection ◽  
Processing Techniques

Measurement of LIGA parts is critical for characterization and understanding of process variables. Traditionally, measurement using coordinate metrology consists of collecting data points from all of the surfaces of a part (e.g., three dimensional data) and comparing these points with target geometry as defined in a CAD file. Systems such as coordinate measurement machines and laser scanners are often used to collect the data. Unfortunately, three dimensional data collection has proven to be quite difficult for mesoscale parts, such as those created using the LIGA process. The inspection techniques used for larger parts cannot be used for parts of this scale because of physical limitations or poor resolution. This paper targets the use of white light interferometry for the analysis of micro-components produced using the LIGA and stereolithography processes. Both of these processes often create parts that are designed to have a constant cross section with planar top and bottom surfaces. Assuming this geometric relationship holds true, the analysis of just the top or bottom surface of the part can provide useful information pertaining to process capability and part geometry. White light interferometry is well-suited to the measurement of these planar surfaces. This paper will discuss techniques used to analyze two dimensional part parameters using white light interferometry in combination with image processing techniques. Several case studies are included to show the abilities of the measurement and processing methods.

scholarly journals A Subspace-Based Compensation Method for the Mutual Coupling in Concentric Circular Ring Arrays for Near-Field Source Localisation

2012 ◽  
Vol 2012 ◽  
pp. 1-13 ◽  
Author(s):  
Mohammed Jainul Abedin ◽  
Ananda Sanagavarapu Mohan
Keyword(s):  
Parameter Estimation ◽  
Mutual Coupling ◽  
Near Field ◽  
Three Dimensional ◽  
Super Resolution ◽  
Circular Ring ◽  
Dipole Antennas ◽  
Field Source ◽  
Full Wave ◽  
Compensation Approach

We propose a technique for compensating the effect of mutual coupling on parameter estimation that is suitable with any subspace-based super-resolution algorithms. A Concentric circular ring array (CCRA) formed using thin dipole antennas in the receiving mode is employed to estimate the parameters of electromagnetic sources located in the radiating near field of the array. A CCRA geometry that obtains a lowest Cramer-Rao lower bound (CRLB) in the presence of array mutual coupling is chosen for investigation. The mutual coupling among antenna elements of the array would affect the orthogonality of subspaces when MUSIC or ESPRIT algorithms are used for parameter estimation. The proposed method obtains a compensation matrix that restores the orthogonality between the subspaces there by improving the accuracy of estimation. To avoid three-dimensional searches, the range parameter is estimated using a cross-correlation-based method. Numerical simulation using a full-wave electromagnetic (EM) solver is employed to demonstrate the effectiveness of the proposed compensation approach.

scholarly journals Infrared nanoscopy and tomography of intracellular structures

2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Katerina Kanevche ◽  
David J. Burr ◽  
Dennis J. Nürnberg ◽  
Pascal K. Hass ◽  
Andreas Elsaesser ◽  
...  
Keyword(s):  
Cross Sections ◽  
Infrared Radiation ◽  
Near Field ◽  
Three Dimensional ◽  
Infrared Image ◽  
Super Resolution ◽  
Chemical Imaging ◽  
Covalent Bonds ◽  
Resolution Imaging ◽  
20 Nm

AbstractAlthough techniques such as fluorescence-based super-resolution imaging or confocal microscopy simultaneously gather both morphological and chemical data, these techniques often rely on the use of localized and chemically specific markers. To eliminate this flaw, we have developed a method of examining cellular cross sections using the imaging power of scattering-type scanning near-field optical microscopy and Fourier-transform infrared spectroscopy at a spatial resolution far beyond the diffraction limit. Herewith, nanoscale surface and volumetric chemical imaging is performed using the intrinsic contrast generated by the characteristic absorption of mid-infrared radiation by the covalent bonds. We employ infrared nanoscopy to study the subcellular structures of eukaryotic (Chlamydomonas reinhardtii) and prokaryotic (Escherichia coli) species, revealing chemically distinct regions within each cell such as the microtubular structure of the flagellum. Serial 100 nm-thick cellular cross-sections were compiled into a tomogram yielding a three-dimensional infrared image of subcellular structure distribution at 20 nm resolution. The presented methodology is able to image biological samples complementing current fluorescence nanoscopy but at less interference due to the low energy of infrared radiation and the absence of labeling.

Three-dimensional microscopy through white light interferometry

2002 ◽  
Author(s):  
Blandine Laude ◽  
Antonello De Martino ◽  
Bernard Drevillon ◽  
L Benattar ◽  
Laurent Schwartz
Keyword(s):  
White Light ◽  
Three Dimensional ◽  
White Light Interferometry
Sign in / Sign up

Export Citation Format

Share Document