PICALO 2006 Paper #903 (Camera Based System for Laser Beam Online Monitoring)

Camera Based System for Laser Beam Online Monitoring
Authors:
Jan Hannweber, Fraunhofer IWS; Dresden Germany
Berndt Brenner, Fraunhofer IWS; Dresden Germany
Eckhard Beyer, Fraunhofer IWS; Dresden Germany
Steffen Bonss, Fraunhofer IWS; Dresden Germany
Presented at PICALO 2006

Surface hardening with high power diode lasers has been developed to an industrial accepted process in the last years. The multiple adoption of this complex process in the industrial environment make great demands on process control, safety und simplification. To meet these demands a special camera based monitoring system has been developed. This system is able to monitor many laser beam characteristics during the hardening process online, which creates new options regarding the process quality control. Furthermore typical commercial high power laser deliver two different wavelength superposed to one beam. For a proper verification of the beam characteristics the system can measure each wavelength separately in real time. It is possible to acquire and control laser beam shaping for example by a scanning system. As sensor a low cost camera is used. All parameters like accuracy, resolution and the measured spectrum are adaptable to the specific requirements. The system can be integrated very easily in existing hardening systems controlled by software. The state of the development of this system is demonstrated on typical applications.

PICALO 2006 Paper #M101 (Fabrication of Microchannels in PMMA by Femtosecond Laser Pulses (Invited Paper))

Fabrication of Microchannels in PMMA by Femtosecond Laser Pulses (Invited Paper)
Authors:
Daniel Day, Centre for Micro-Photonics; Victoria Australia
Min Gu, Centre for Micro-Photonics; Hawthorn VIC Australia
Presented at PICALO 2006

Microchannels are fabricated in a poly(methyl methacrylate) substrate by high repetition rate, nanojoule femtosecond laser pulses. Microchannels with diameters of 8 - 15 m can be fabricated at a wavelength of 750 nm and a fabrication speed of 800 m/s using 80 fs pulses at a repetition rate of 80 MHz with energy of 0.9 nJ/pulse. The size and shape of the microchannels can be controlled by changing the fabrication parameters of speed, the number o...

PICALO 2006 Paper #M102 (Micro Laser Sintering (microLS) for Rapid Prototyping of Metal-ceramics)

Micro Laser Sintering (microLS) for Rapid Prototyping of Metal-ceramics
Authors:
Peter Stippler, Laser Zentrum Hannover e.V.; Hannover Germany
Stefan Czerner, Laser Zentrum Hannover e.V.; Hannover Germany
Andreas Ostendorf, Laser Zentrum Hannover e.V.; Hannover Germany
Paolo Matteazzi, CSGI and MBN; Florence Italy
Gerrit Hohenhoff, Laser Zentrum Hannover e.Z.; Hannover Germany
Presented at PICALO 2006

The world market for micro system technology is constantly raising the technical demands for the production of metallic tools or functional parts. Currently, the methods of the rapid prototyping area are in relation to the product development on...

PICALO 2006 Paper #M103 (Micro Joining of Dissimilar Metals with a Pulsed Nd:Yag Laser)

Micro Joining of Dissimilar Metals with a Pulsed Nd:Yag Laser
Authors:
Mohammed Naeem, GSI Group, Inc.; Rugby Great Britain
Presented at PICALO 2006

Majority of applications in electronics, medical devices industry requires micro joining of dissimilar materials. In principle, a laser can weld any material, which can be joined by conventional processes. In the welding of dissimilar metals, good solid solubility is essential for sound weld properties. The trends of joining dissimilar metals and miniaturisation of components are offering high challenges for welding methods. The weldability of dissimilar metals depends on many different factors. The physical properties have a high influence on the...

PICALO 2006 Paper #M104 (Laser Replication Process using Photo-etchable Glass-ceramics and Polymers)

Laser Replication Process using Photo-etchable Glass-ceramics and Polymers
Authors:
Joohan Kim, Seoul National University of Technology; Seoul Korea
Xianfan Xu, Purdue University; Lafayette IN USA
Presented at PICALO 2006

Micro fluidic devices are widely used as typical micro devices and they have many applications in clinical diagnostics, drug delivery and micro electronics cooling. A micro replication process can be used for fabricating micro fluidic devices and a laser replication process using glass-ceramics and polymers is investigated in this work. This process is based on the micro stamping replication process, also referred to as hot embossing lithography. A glass-ceramic m...

PICALO 2006 Paper #M105 (A Process Study of Laser Micro-Drilling Vias for Wafer Level Chip Scale Packaging)

A Process Study of Laser Micro-Drilling Vias for Wafer Level Chip Scale Packaging
Authors:
Hong Yu Zheng, Singapore Institute of Manufacturing Technology; Singapore
Presented at PICALO 2006

Along with the trends of the product minimization, wafer level chip scale package (WLCSP) has become a new solution to advanced packaging. Formation of micro-vias with desired patterns is a critical process step. Currently micro-vias are achieved through photolithographic technology, which is lengthy, time-consuming and costly. In order to improve the productivity and reduce the cost of the via formation process, it is critical to develop a simpler and more cost-effective drilling technology. The successfu...

PICALO 2006 Paper #M107 (Laser Beam Micro-Welding with Single Mode Fibre Lasers)

Laser Beam Micro-Welding with Single Mode Fibre Lasers
Authors:
Florian Wagner, BIAS Bremer Institut Fuer Angewandte Strahltechnik; Bremen Germany
Harald Kohn, BIAS; Germany
Presented at PICALO 2006

Single mode fibre lasers enable the welding of thin sheet materials. Although laser power is comparably low, the excellent beam quality of M2 < 1,1 provides intensities sufficient for keyhole welding. Especially for micro-fabrication, it is now possible to weld at considerable processing speed of 100 m/min and more, whilst heat input and thus distortion is minimized. Moreover, the weld pool and thus weld geometry is very narrow, consequently reducing the risk of weld imperfections due...

PICALO 2006 Paper #M108 (Writing Waveguide in Photosensitive Glass Using Ultrafast Laser)

Writing Waveguide in Photosensitive Glass Using Ultrafast Laser
Authors:
D.K.Y. Low, Singapore Institute of Manufacturing Technology; Singapore
K.J. Moh, Nanyang Technological Univ.; Singapore
Zhongli Li, SIMTech; Singapore
G.C. Lim, Singapore Institute of Manufacturing Technology; Singapore
Presented at PICALO 2006

We report two methods of fabricating waveguides in photosensitive Ag+ doped Foturan glass by femtosecond (fs) laser writing and subsequent annealing. The first method, which involved writing at laser energy higher than the optical breakdown threshold, resulted in microstructural changes and a refractive index increase. In contrast, the ...

PICALO 2006 Paper #M202 (Topographical Electrodes for Poling Lithium Niobate)

Topographical Electrodes for Poling Lithium Niobate
Authors:
Benjamin Johnston, Macquarie University; Macquarie Australia
Michael Withford, Macquarie University; Macquarie Australia
Presented at PICALO 2006

Periodically poled materials continue to be of great interest due to their applications in both bulk nonlinear optics and all-optical processing systems. Many groups continue to explore alternative techniques to lithographic surface electrodes for defining the domain pattern. The key objectives of these studies are to reduce the minimum domain size, produce uniformity in the domain structures and improve the cost effectiveness and speed of fabrication. We report progress on an...

PICALO 2006 Paper #M203 (Void Generation and Three-dimensional Photonic Crystal Fabrication in a Lithium Niobate Crystal by Use of Micro-explosion)

Void Generation and Three-dimensional Photonic Crystal Fabrication in a Lithium Niobate Crystal by Use of Micro-explosion
Authors:
Guangyong Zhou, Swinburne University of Technology; Hawthorn, VIC Australia
Min Gu, Swinburne University of Technology; Hawthorn Australia
Presented at PICALO 2006

Smooth void dots and void channels have been generated efficiently in some low refractive index materials such as polymers and glasses by use of a femtosecond laser induced microexplosion method and have been used to fabricate 3D photonic crystals. In order to get complete bandgap, a high refractive index material need to be used. Lithium niobate (LiNbO3) crystal is a good candidate because o...