Archiv des Autors: Stefan Bergfeld

New laser in our labs in Aachen

For the activities of processing of thin semiconductor film we acquired a new laser system.

Specification:

wave length: λ = 515 nm

pulse length: τ = 900 pico seconds

The new laser will be equipped with a galvo scanning system and is available in our new facility in Aachen (Roermonder Strasse) in January 2018. The whole system will be compact and allows on-side laser tests at your place.

New optical assembly for quasi-tophat beam shaping

InnoVision has developed a new optical assembly for generating a quasi-tophat laser beam profile from gaussian beams.

laser beam befor shaping

laser beam after shaping

In most applications for selective ablation using of gaussian beam profiles are impossible.Especially with fs laser where nonlinear absorption becomes predominant. Therefore beam shaping is crucial. Nowadays tophat converters are used that generate from gaussian profiles tophat beam profiles. Exactly in working distance the beam profile is very good. But slightly off working distance the beam profile becomes dramatically worse.

To overcome this issue InnoVision developed a solution for tophat profile where the tophat changes only slightly with different working distances. Therefore the tophat is not ideal. The Quasi tophat is at the beam waste. Before and behind the ideal working distance the peak intensity is lower. That prevents damages. (Beam shaper using diffractive optical elements (DOE) usually have strong hotspots behind the ideal working distance. see https://youtu.be/79GlQdgFxbI

Our solution converts beams with M2 < 1,5 to beams with  M2 between 1,5 and 2,5.  This solution allows better integration in industrial production systems and the use of galvo scanner. Also focus controls are no longer important. The processing of 3D parts is much more easy.

The beam shaping unit has been testes at the laser labs at TH Köln campus Gummersbach.

The main application of the beam shaping unit is:

  • ps and fs laser where multimode fibers can not be used,
  • single-mode fiber laser.

The system can be easier integrated in laser material processing systems than „gauss-to-tophat-converter“.

We sell the optical assembly or we develop a customized solution for your systems with laser, scanner and bean path.

Now, we are working on combining quasi-tophat with Bessel focus to achieve very long working distances. This unit can be easily used in in the next generation of ps and fs laser that will have much  higher pulse energy. For this laser we also developed a multi-spot solution for galvo scanners. In contrast to usual multi-spot solution using DOEs our solution allows to adjust beam distances and the energy of each beam.

Imaging pocket spectroscopes now available

We developed an imaging pocket spectroscope. It can be used for visualize the spectrum of light sources,  the rendering of colors or printed documents, or the absorption lines of minerals.

Additional to usual spectroscopes this imaging spectroscope can show the spectrum of particular areas. In can focus to infinity or any other closer distance.

The imaging optics can be disassembled for using as hand microscope. And the spectroscope can be used in the usual way. 

Diameter: 1,5 cm

Length:  7,8 cm

Weight: 18 g

The images show different spectra of florescence tubes. The images are taken trough a smart phone in a distance of approximately 4 m.

The spectral resolution is suitable to see the Fraunhofer lines in daylight spectrum.

The spectroscope is available with your individual laser engraving.

We sell small volumes via Ebay. Please contact us for higher volumes or for customized spectroscopes.

 

New laser safety regulation for laser machines (laser class 1)

Since End of 2016 there are new regulations regarding laser safety („Laserklasse 1“ in Germany).

New: direct laser light need to be considered as well as secondary light! 

During laser processing mostly a plasma is generated. This plasma emitted also UV light. Most laser windows do not have a sufficient UV protection.

In our laser safety reviews we also measure the intensity of this UV light, the UV transmission of laser windows and shielding of the laser light and the secondary light.  For any question sent email to „bergfeld (at) Inno-vision.de“

 

OLEDs – High Quality of Light

InnoVision finished a  project about „quality of light“. Therefore we measured different light sources. This results we are publishing now.

Fluorescence lambs have poor light because they emit light only in small spectral ranges (peaks in the spectrum) therefore the color appearance unter fluorescents lambs is changed. Experts say, the Color Rendering Index (CRI) is low. Light bulbs and halogen lambs have a brought spectrum, but they emit high intensity in infra red (IR) and have low intensity in the blue region. Therefor they are very inefficient and not good for work spaces where cold white (with more blue intensity) is preferable. LEDs and OLEDs emit light in a brought spectrum. Therefore the CRI is very good. Especially the OLED has no strong minimum in the spectrum. But the best light is a combination of OLED and LED

Spectra of different light sources.

The Laser Labs at TH Köln Start to Operate

The Laser Labs at TH Köln Start to Operate

At the „Technische Hochschule Köln“ at Campus Gummersbach new labs for laser productions processes are builded up. The labs is focussing on laser processes in combination with coating processes of functional surfaces. One main topic is Thin-Film, Organic and Printed Electronic

Following systems are already running:

  • ns laser 1064 nm
  • ns laser 532 nm
  • CW CO2-Laser 10.6 µm
  • AFM
  • Spectrometer

InnoVision is cooperating with the labs for laser productions processes