Figure 1 and 2

Product News June 2010

For further information please contact Klaus Reinecke (k.reinecke@limo.de).

Please visit us at the 25th European Photovoltaic Solar Energy: level 2, hall 2, booth A48.  

LIMO beam transformation optics are used for collimation and beam shaping of laser diode bars. The optics shape the extremely asymmetrical light beams of the emitters of the bars into symmetrical beam profiles enabling highly efficient fiber coupling.

Data sheet: Compact BTS

For further information, please contact Klaus Reinecke, k.reinecke@limo.de.

The 120 W fiber-coupled industrial laser system LIMO120-F400-SL808-103 is combined with the processing head IOS00019x-series. This device generates a homogeneously illuminated field under 35° angle of incident that fits to solar cell sizes up to 210 x 210 mm. The center wavelength of 790…808 nm is essential for the separation of excitation source and signal light. In addition, small bandwidth versions (< 1 nm) are available as an option.

Solar cell inspection tools based on the LIMO laser source operate with a single light source compared to other inspection tools using two light sources. That makes the tools more compact and reduces materials as well as assembly costs.
A special advantage of an in-line inspection tool: The quality inspection of the solar cells occurs at the full production speed without interrupting the production. Those advantages guarantee high productivity and low cost per tested unit.

Homogeneously illuminated fields create value in metrology applications in a variety of industries, including medicine or chemical analysis.

Graphic: asymmetric homogeneous diode laser illumination

For further information please contact Klaus Reinecke (k.reinecke@limo.de).

Please visit us at the 25th European Photovoltaic Solar Energy: level 2, hall 2, booth A48.  

At the Photonics West 2010 LIMO presented a new concept for beam shaping and fiber coupling of laser diode bars (mini-bar structure 90 µm / 500 µm) with a single micro optical element.

Typically, high power diode lasers modules are made of laser diode bars and several optical elements. This assembly is often challenging in terms of numbers of components, numbers of alignment and mounting steps and therefore finally critical in terms of manufacturing costs. The new concept requires only one single multifunctional micro optical element to couple the emitted light into a fiber.

LIMO tested the monolithic fiber coupling optic with a 50 W laser mini-bar into a 600 µm fiber core (NA 0.22). A high coupling efficiency of 90% was reached.
Further advantages of this approach are:
- reduced material costs due to use of just one optical element
- easy and fast alignment
- shorter production time due to just one mounting step
- less reflection due to just two optical surfaces with antireflection coating
- compact laser module design

The monolithic fiber coupling optics is suitable for the mass production of high power diode laser systems for cost sensitive applications with limited requirements on brightness.

Datasheet monolithic fiber coupler

For further information contact Klaus Reinecke, k.reinecke@limo.de.

A homogeneous beam profile, which is adapted to the customized seam geometry (e.g. a line), is used instead of a point-shaped laser beam. Most important advantage: Instead of time-consuming positioning of the laser beam at the welding points and subsequent scanning of the complete seam, the whole process is performed in one step with a single short-time laser radiation. The results are increased processing speed and throughput. Furthermore, the welding process is more error-free, because of a bigger process window and a stable process control.

Also the quality of the welding is improved: The welding seam is non-porous and bubble-free with constant width. Destructive tests of the work pieces show a continuously high stability of the welding seam along the whole contour.
Reduced investment costs compared to scanner-based systems for quasi-simultaneous welding provide additional benefits.

For further information contact Peter Bruns, p.bruns@limo.de.
Please visit us at the IVAM joint pavilion at the trade show Hannover Messe: hall 6, booth H 16 / I1.

 ”With LIMO technology we were able to get in our photovoltaic applications 50% higher current with the multi-crystalline silicon thin film solar cells. (...) For the first time we demonstrated an error free production of this new cell type. With this result we have opened the doors for an industrial use of this highly efficient solar cell.“ said Dr. Fritz Falk from IPHT in Jena. Besides the higher efficiency of the solar cells the coating quality was also enhanced.

After the L³ LIMO Line Laser^® technology was tested under laboratory conditions,   the next step is its validation for industrial mass production.
The L³ LIMO Line Laser^® technology offers the following advantages:
- Laser crystallization without heating the substrate
- Shorter cycle time per panel (< 30 s) 

For further information contact Dirk Hauschild, d.hauschild@limo.de.
Please visit us at the IVAM joint pavilion at the trade show Hannover Messe: hall 6, booth H 16 / I1.

In addition to process development, these laser sources are also designed for improvement of new thin films (e.g. solar cells, semiconductor devices) and other applications with strongest demand for high energy efficiency. The line lasers are optimized for annealing, crystallization and tempering of thin films with high speed linear scanning processes. Furthermore, the lasers can also be used for rapid thermal inspection and quality assurance.

The L³ LIMO Line Lasers^® based process development tools are equipped with, e.g., 450 W to 950 W laser sources that run in a cw or pulsed mode with a power density of up to several 100 kW/cm² and a typical line length of 10 mm to 30 mm. In combination with 3 linear stages the beam moves across the target with up to 1 m/s velocity. To transfer the process into production systems the laser sources can be scaled up to several meters line length for optimized productivity and profit.

For further information, please contact Dirk Hauschild, d.hauschild@limo.de.

This contactless laser welding process can be done without any chemical additives and is particularly suitable for components with a high surface quality. The integrated process- and mode control provides a basis for a consistent process management, even concerning components with unsteady material properties or thickness as well as with tight temperature tolerances. 

Interested users are invited to come to LIMO’s Applications Center to get to know the possibilities. With LIMO’s support, users can also work on test components and small batch series or integrate customized laser systems into their production lines.

For further information, please contact Peter Bruns, p.bruns@limo.de

As a company that offers solutions, we are able to provide exactly what your needs require: All our modules can be adjusted to your specifications. Please contact us!