Spectral-domain optical coherence tomography for conformal coating thickness measurement on printed circuit board

2018 ◽  
Author(s):  
Xiao Shao ◽  
Xiaojun Yu ◽  
Xinjian Chen ◽  
Jianhua Mo ◽  
Linbo Liu ◽  
...  
Keyword(s):  
Optical Coherence Tomography ◽  
Coating Thickness ◽  
Printed Circuit Board ◽  
Thickness Measurement ◽  
Circuit Board ◽  
Spectral Domain ◽  
Optical Coherence ◽  
Conformal Coating ◽  
Printed Circuit ◽  
Coating Thickness Measurement

Evaluation of Central Corneal Thickness Measurement With RTVue Spectral Domain Optical Coherence Tomography in Normal Subjects

Cornea ◽  
2011 ◽  
Vol 30 (2) ◽  
pp. 121-126 ◽  
Author(s):  
Harsha Laxmana Rao ◽  
Addepalli Uday Kumar ◽  
Anjul Kumar ◽  
Swathi Chary ◽  
Sirisha Senthil ◽  
...  
Keyword(s):  
Optical Coherence Tomography ◽  
Central Corneal Thickness ◽  
Corneal Thickness ◽  
Normal Subjects ◽  
Thickness Measurement ◽  
Spectral Domain ◽  
Optical Coherence

scholarly journals In vivo tear film thickness measurement and tear film dynamics visualization using spectral domain optical coherence tomography

2015 ◽  
Vol 23 (16) ◽  
pp. 21043 ◽  
Author(s):  
Valentin Aranha dos Santos ◽  
Leopold Schmetterer ◽  
Martin Gröschl ◽  
Gerhard Garhofer ◽  
Doreen Schmidl ◽  
...  
Keyword(s):  
Optical Coherence Tomography ◽  
Film Thickness ◽  
Tear Film ◽  
Thickness Measurement ◽  
Spectral Domain ◽  
Optical Coherence ◽  
Film Thickness Measurement

scholarly journals Retinal Thickness Measurement Obtained with Spectral Domain Optical Coherence Tomography Assisted Optical Biopsy Accurately Correlates with Ex Vivo Histology

PLoS ONE ◽  
2014 ◽  
Vol 9 (10) ◽  
pp. e111203 ◽  
Author(s):  
Lee R. Ferguson ◽  
Sandeep Grover ◽  
James M. Dominguez II ◽  
Sankarathi Balaiya ◽  
Kakarla V. Chalam
Keyword(s):  
Optical Coherence Tomography ◽  
Retinal Thickness ◽  
Ex Vivo ◽  
Thickness Measurement ◽  
Spectral Domain ◽  
Optical Biopsy ◽  
Optical Coherence

Contamination profile on typical printed circuit board assemblies vs soldering process

2014 ◽  
Vol 26 (4) ◽  
pp. 194-202 ◽  
Author(s):  
Helene Conseil ◽  
Morten Stendahl Jellesen ◽  
Rajan Ambat
Keyword(s):  
Printed Circuit Board ◽  
Circuit Board ◽  
Content Type ◽  
Contamination Control ◽  
Conformal Coating ◽  
Printed Circuit ◽  
Soldering Process ◽  
Wave Soldering ◽  
Solder Flux ◽  
Set Up

Purpose – The purpose of this paper was to analyse typical printed circuit board assemblies (PCBAs) processed by reflow, wave or selective wave soldering for typical levels of process-related residues, resulting from a specific or combination of soldering processes. Typical solder flux residue distribution pattern, composition and concentration are profiled and reported. The effect of such contaminants on conformal coating was tested. Design/methodology/approach – Presence of localized flux residues was visualized using a commercial residue reliability assessment testing gel test and chemical structure was identified by Fourier transform infrared spectroscopy, while the concentration was measured using ion chromatography, and the electrical properties of the extracts were determined by measuring the leak current using a twin platinum electrode set-up. Localized extraction of residue was carried out using a commercial critical contamination control extraction system. Findings – Results clearly show that the amount and distribution of flux residues are a function of the soldering process, and the level can be reduced by an appropriate cleaning. Selective soldering process generates significantly higher levels of residues compared to the wave and reflow process. For conformal coated PCBAs, the contamination levels generated from the tested wave and selective soldering process are found to be enough to generate blisters under exposure to high humidity levels. Originality/value – Although it is generally known that different soldering processes can introduce contamination on the PCBA surface, compromising its cleanliness, no systematic work is reported investigating the relative levels of residue introduced by various soldering processes and its effect on corrosion reliability.

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