Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Clear view for the Extremely Large Telescope – LZH develops IR narrowband filter

14.05.2014

When telescopes look into space, they usually have only a limited view, even on star-bright nights – molecules in the atmosphere „block“ their view. Scientists at the Laser Zentrum Hannover e.V. (LZH) have developed and produced narrowband filters for the European Extremely Large Telescope (E-ELT), which block interfering signals.

In contrast to telescopes stationed in outer space, earth based telescopes inevitably measure interference signals in the atmosphere. In order to filter out this static, scientists at the LZH are developing special coatings for the optical components of the E-ELT. The work group Coatings has already developed first filters with a thickness of 60 to 100 µm on a substrate with a diameter of 100 mm. The narrowband filters block out interference and transmit signals into space in narrow bands in the infrared range (IR). The coating, made using ion beam sputtering, must have a homogeneity of 0.1% or less.


Image of the planned E-ELT, in which the IR narrowband filter of the LZH can be found.

Swinburne Astronomy Productions/ESO

Filters make more exact measuring possible

Production of complex filters is a challenge, since a compromise between the coating thickness and the quality must always be found. Because of this, Dr. Stefan Günster, head of the Coatings Group, works closely with the astronomers of the Max Planck Institute for Extraterrestrial Physics and the University Observatory of the Ludwig-Maximilian-Universität München. The filter coating should improve the signal-to-noise ratio. This means the measurement time can be shortened, and thus more exact measurements are possible.

The scientists working with Dr. Günster use a special wideband filter monitor developed by the LZH, which covers a very wide wavelength range of 380 to 1700 nm. “With this instrument we can monitor the coating during production, and optimize it if necessary”, explains Stefan Günster. “Since coating the filter is very sophisticated, due to its thickness, we can save considerable development time doing so.”

Examining form accuracy

The relatively high physical thickness of the coatings places mechanical stress on the optics: the filters are deformed and influence the measurements. “We are presently working on processes, which can be used to monitor and control the form accuracy of the optics,” adds Dr. Günster.

As soon as the coating process has become established, the narrowband filters can also be used in other areas: for example for biological and medical applications that need high quality measurements in the IR range.

The Coating Group will be at the Optatec from May 20th to 22nd, 2014, in Hall 3, Stand H39.

Lena Bennefeld | Laser Zentrum Hannover e.V.
Further information:
http://www.lzh.de

Further reports about: Coatings E-ELT LZH Laser Observatory Optatec Physics Telescope atmosphere telescopes wavelength

More articles from Physics and Astronomy:

nachricht SF State astronomer searches for signs of life on Wolf 1061 exoplanet
20.01.2017 | San Francisco State University

nachricht Molecule flash mob
19.01.2017 | Technische Universität Wien

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Traffic jam in empty space

New success for Konstanz physicists in studying the quantum vacuum

An important step towards a completely new experimental access to quantum physics has been made at University of Konstanz. The team of scientists headed by...

Im Focus: How gut bacteria can make us ill

HZI researchers decipher infection mechanisms of Yersinia and immune responses of the host

Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...

Im Focus: Interfacial Superconductivity: Magnetic and superconducting order revealed simultaneously

Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.

While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...

Im Focus: Studying fundamental particles in materials

Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales

Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...

Im Focus: Designing Architecture with Solar Building Envelopes

Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.

As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Sustainable Water use in Agriculture in Eastern Europe and Central Asia

19.01.2017 | Event News

12V, 48V, high-voltage – trends in E/E automotive architecture

10.01.2017 | Event News

2nd Conference on Non-Textual Information on 10 and 11 May 2017 in Hannover

09.01.2017 | Event News

 
Latest News

Bodyguards in the gut have a chemical weapon

20.01.2017 | Life Sciences

SF State astronomer searches for signs of life on Wolf 1061 exoplanet

20.01.2017 | Physics and Astronomy

Treated carbon pulls radioactive elements from water

20.01.2017 | Materials Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>