Authentication and Testing of Banknotes Using Laser Multiphoton Electron Extraction Spectroscopy (MEES)

In laser multiphoton electron extraction spectroscopy (MEES), the photo-charges extracted from a surface by a pulsed laser beam are recorded as a function of laser wavelength. We report the first application of this spectroscopy to banknotes. Various banknotes from different countries, authentic and counterfeit, have been tested. The results indicate that MEES spectra are both informative (many peaks) and reproducible. The spectra allow for clear distinction between authentic and counterfeit banknotes. Actually, MEES provides a unique fingerprint of the banknotes, so that distinction between various forgery methods (printer used) is also possible.

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Tempering rapidly solidified ductile cast iron by pulsed laser beam reprocessing

Scripta Metallurgica et Materialia ◽

10.1016/0956-716x(94)90014-0 ◽

1994 ◽

Vol 31 (4) ◽

pp. 433-438 ◽

Cited By ~ 4

Author(s):

H.M. Wang ◽

H.W. Bergmann

Keyword(s):

Cast Iron ◽

Laser Beam ◽

Pulsed Laser ◽

Ductile Cast Iron ◽

Rapidly Solidified ◽

Pulsed Laser Beam

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Quasi-one-dimensional thermal deformation and displacement of the surface of a solid in a pulsed laser beam

Physics of the Solid State ◽

10.1134/1.1130214 ◽

1997 ◽

Vol 39 (12) ◽

pp. 1985-1988

Author(s):

S. V. Vintsents ◽

S. G. Dmitriev ◽

K. I. Spiridonov

Keyword(s):

Laser Beam ◽

Thermal Deformation ◽

Pulsed Laser ◽

One Dimensional ◽

Pulsed Laser Beam

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LASERTRON, a new type of RF source using photoemission triggered by a pulsed laser beam

Nuclear Instruments and Methods in Physics Research Section A Accelerators Spectrometers Detectors and Associated Equipment ◽

10.1016/0168-9002(85)90457-7 ◽

1985 ◽

Vol 238 (2-3) ◽

pp. 215-219 ◽

Cited By ~ 2

Author(s):

Y. Fukushima ◽

T. Kamei ◽

H. Matsumoto ◽

H. Mizuno ◽

I. Sato ◽

...

Keyword(s):

Laser Beam ◽

Pulsed Laser ◽

New Type ◽

Pulsed Laser Beam

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Study on the microstructure and mechanical properties of Nd:YAG pulsed laser beam weld of UNS-C17200 copper beryllium alloy

Journal of Materials Processing Technology ◽

10.1016/j.jmatprotec.2010.04.005 ◽

2010 ◽

Vol 210 (11) ◽

pp. 1472-1481 ◽

Cited By ~ 14

Author(s):

S.A.A. Akbari Mousavi ◽

S.T. Niknejad

Keyword(s):

Mechanical Properties ◽

Laser Beam ◽

Pulsed Laser ◽

Microstructure And Mechanical Properties ◽

Copper Beryllium ◽

Pulsed Laser Beam

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High precision balanced mode polarimetry with a pulsed laser beam

Optics Communications ◽

10.1016/0030-4018(95)00288-j ◽

1995 ◽

Vol 119 (3-4) ◽

pp. 403-414 ◽

Cited By ~ 13

Author(s):

M. Bouchiat ◽

D. Chauvat ◽

J. Guéna ◽

Ph. Jacquier ◽

M. Lintz ◽

...

Keyword(s):

Laser Beam ◽

High Precision ◽

Pulsed Laser ◽

Pulsed Laser Beam

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Comparative Study on Pulsed Laser Welding Strategies for Contacting Lithium-Ion Batteries

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1140.312 ◽

2016 ◽

Vol 1140 ◽

pp. 312-319 ◽

Cited By ~ 3

Author(s):

Patrick Schmitz

Keyword(s):

Laser Beam ◽

Comparative Study ◽

Weld Seam ◽

Laser Beam Welding ◽

Pulsed Laser ◽

Pulsed Laser Beam Welding ◽

Joining Process ◽

Suitable Process ◽

Pulsed Laser Beam ◽

Battery Cells

The transition towards renewable energy implicates more decentralized and time-dependent ways of energy generation. In order to deal with the resulting fluctuation in energy supply, local storage systems are necessary. Larger systems may consist of thousands of battery cells. Therefore, the reliable interconnection between the individual battery cells is the basic prerequisite for the production of these systems. It has been demonstrated that laser beam welding is a suitable process for the contacting of batteries. However, due to the high requirements regarding the heat input and the reproducibility of the joining process, further investigations are necessary. Within this work, experiments on pulsed laser beam welding of nickel-plated DC04 steel were conducted. Four different pulsed welding strategies were analyzed in a preliminary study in order to develop a method for obtaining suitable process parameters while reducing the amount of free parameters. Subsequently, a comparative study between the rectangular pulse, the shaped pulse, the spike pulse and the sloping pulse was carried out. The weld seam properties as well as the electrical and the mechanical properties of the connection joints were evaluated. The results presented in this paper indicate a high eligibility of pulsed laser beam welding as a joining process for the connection of battery cells. For all analyzed pulsed welding strategies a homogeneous weld seam without full penetration was observed. Similar electrical resistances for all strategies were measured despite the comparatively small total joint area for the discretely pulsed weld seams.

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