@inproceedings{KriegCarreDoehringetal.2022, author = {Krieg, Janina and Carre, Antoine and D{\"o}hring, Thorsten and Hartmann, Peter and Hull, Tony and Jedamzik, Ralf and Westerhoff, Thomas}, title = {The past decade of ZERODUR® glass-ceramics in space applications}, series = {Proceedings of SPIE}, volume = {2022}, booktitle = {Proceedings of SPIE}, number = {12180}, publisher = {SPIE}, organization = {SCHOTT AG}, doi = {https://doi.org/10.1117/12.2628956}, pages = {121805N-1 -- 121805N-15}, year = {2022}, abstract = {For the past four decades, ZERODUR® glass ceramics has flown on many satellites including the prominent space missions METEOSAT, Hubble Space Telescope, CHANDRA, and LISA pathfinder. Firstly, this unique material is chosen as mirror substrate for high precision optics due to its extreme thermal stability. Its near-zero thermal expansion over a wide temperature range of several tens of Kelvin is homogenous within the entire volume. This enables control of the ZERODUR®'s surface profile at the 10-picometer level. SCHOTT has conducted comprehensive material characteristics studies on the mechanical properties and the radiation environment effects experienced in realistic orbits to define the suitability of ZERODUR® to survive both high loads during launch and to support long-term missions, respectively. Besides these advantageous material properties, this glass-ceramics can be extremely light-weighted by precision grinding enabled by the new SCHOTT competence center for machining and metrology. In this paper, we will continue to trace the recent developments of ZERODUR® glass ceramics as space material in the context of selected missions flown since 2009 and those anticipated. Major milestones such as the LISA pathfinder mission are discussed. Furthermore, we outline the viable use of ZERODUR® for great observatory architectures for IR/O/UV spaceborne telescopes. The objective of this paper is to supplement an earlier review of the use of ZERODUR® for space applications in the past decade and to summarize the latest progress and results of material studies toward very efficient production capabilities for high-performance light-weighted mirror substrates.}, subject = {Spiegelteleskop}, language = {en} } @inproceedings{DoehringZeisingStieglitzetal.2022, author = {D{\"o}hring, Thorsten and Zeising, Sebastian and Stieglitz, Veronika and Burwitz, Vadim and Rukdee, Surangkhana and Friedrich, Peter and Jelinek, Martin and Hudec, Rene}, title = {R{\"o}ntgenteleskop-Funktionstests durch Beobachtung astronomischer Objekte am sichtbaren Nachthimmel}, series = {DGaO Proceedings}, volume = {2022}, booktitle = {DGaO Proceedings}, publisher = {DGaO}, organization = {TH Aschaffenburg}, issn = {1614-8436}, pages = {1 -- 2}, year = {2022}, abstract = {Lobster-Eye-R{\"o}ntgenteleskope nutzen reflektierende Planspiegel unter streifendem Einfall und zeichnen sich durch ein großes Beobachtungsfeld aus. Die Spiegel reflektieren auch sichtbare Strahlung hervorragend. Nach R{\"o}ntgen-messungen im Labor wurden nun weitere Tests durchgef{\"u}hrt, um die Abbildungs-eigenschaften mit realen Objekten des sichtbaren Himmels zu untersuchen.}, subject = {R{\"o}ntgenteleskop}, language = {de} } @inproceedings{DoehringStollenwerkSchmittetal.2022, author = {D{\"o}hring, Thorsten and Stollenwerk, Manfred and Schmitt, Paul and Szeghalmi, Andrea}, title = {Umweltbest{\"a}ndige Spiegelbeschichtungen aus Iridium f{\"u}r den infraroten Spektralbereich}, series = {DGaO Proceedings}, volume = {2022}, booktitle = {DGaO Proceedings}, number = {123}, publisher = {DGaO}, organization = {TH Aschaffenburg}, issn = {1614-8436}, pages = {1 -- 2}, year = {2022}, abstract = {Das Edelmetall Iridium ist hart; extrem dicht; thermisch, mechanisch und chemisch stabil; weist eine hohe Reflektivit{\"a}t im mittleren und fernen Infrarot auf und hat eine hohe Best{\"a}ndigkeit gegen{\"u}ber Umwelteinfl{\"u}ssen - auch ohne weitere Schutzschichten. Es wurden die komplexen Brechungsindizes f{\"u}r Iridium-Spiegelbeschichtungen bestimmt, welche vorhandene Literaturwerte erg{\"a}nzen.}, subject = {Iridium}, language = {de} } @inproceedings{HudecGilleGuimbelotetal.2022, author = {Hudec, Rene and Gille, Florian and Guimbelot, Elzear and Tichy, Vladimir and D{\"o}hring, Thorsten}, title = {Effective areas of astronomical X-ray optics for cubesats and rocket experiments}, series = {DGaO Proceedings}, volume = {2022}, booktitle = {DGaO Proceedings}, number = {123}, publisher = {DGaO}, organization = {Technische Universit{\"a}t Prag}, issn = {1614-8436}, pages = {1 -- 2}, year = {2022}, abstract = {The effective area is one of the main telescope parameters when justifying real space application. We discuss the estimation of the effective collecting area of an X-ray telescope by two different methods, an analytical method and a simulation algorithm, and then compare the results. The Lobster Eye type telescopes considered here are designed for rocket experiments and CubeSat flights.}, subject = {R{\"o}ntgenteleskop}, language = {en} } @article{SchmittFeldeDoehringetal.2022, author = {Schmitt, Paul and Felde, Nadja and D{\"o}hring, Thorsten and Stollenwerk, Manfred and Uschmann, Ingo and Hanemann, Kevin and Siegler, Marie and Klemm, Georg and Gratzke, Nancy and T{\"u}nnermann, Andreas and Schwinde, Stefan and Schr{\"o}der, Sven and Szeghalmi, Adriana}, title = {Optical, structural, and functional properties of highly reflective and stable iridium mirror coatings for infrared applications}, series = {Optical Materials Express}, volume = {2022}, journal = {Optical Materials Express}, number = {12 / 2}, doi = {10.1364/OME.447306}, pages = {545 -- 559}, year = {2022}, abstract = {Metallic coatings are essential for numerous optical systems due to their high and broadband refl ectivity in the infrared spectral range. In contrast to well-established (protected)silver and gold mirror coatings, iridium is environmentally durable, referring to ISO 9211-3 and thermally stable up to 600 °C even without protective layers, as demonstrated. Additionally,the optical and related structural properties of atomic layer deposited (ALD) and magnetron sputtered (MS) Ir coatings were investigated using spectrophotometry, FTIR, ellipsometry, WLI,AFM, XRR, XRD, SEM, and electrical resistivity measurements. The properties of Ir ALD and Ir MS coatings diff er due to their topography and microstructure.}, subject = {Iridium}, language = {en} } @article{SchmittFeldeDoehringetal.2022, author = {Schmitt, Paul and Felde, Nadja and D{\"o}hring, Thorsten and Stollenwerk, Manfred and Uschmann, Ingo and Hanemann, Kevin and Siegler, Marie and Klemm, Georg and Gratzke, Nancy and T{\"u}nnermann, Andreas and Schwinde, Stefan and Schr{\"o}der, Sven and Szeghalmi, Adriana}, title = {Optical, structural, and functional properties of highly reflective and stable iridium mirrorcoatings for infrared applications: supplement}, series = {Optical Materials Express}, volume = {2022}, journal = {Optical Materials Express}, number = {12/2}, doi = {10.6084/m9.figshare.17121509}, pages = {545 -- 559}, year = {2022}, abstract = {Metallic coatings are essential for numerous optical systems due to their high and broadband refl ectivity in the infrared spectral range. In contrast to well-established (protected)silver and gold mirror coatings, iridium is environmentally durable, referring to ISO 9211-3 and thermally stable up to 600 °C even without protective layers, as demonstrated. Additionally,the optical and related structural properties of atomic layer deposited (ALD) and magnetron sputtered (MS) Ir coatings were investigated using spectrophotometry, FTIR, ellipsometry, WLI, AFM, XRR, XRD, SEM, and electrical resistivity measurements. The properties of Ir ALD and Ir MS coatings diff er due to their topography and microstructure.}, subject = {Iridium}, language = {en} } @misc{DoehringStollenwerkSchmittetal.2022, author = {D{\"o}hring, Thorsten and Stollenwerk, Manfred and Schmitt, Paul and Szeghalmi, Adriana}, title = {Umweltbest{\"a}ndige Spiegelbeschichtungen aus Iridium f{\"u}r den infraroten Spektralbereich}, publisher = {DGaO}, organization = {TH Aschaffenburg}, pages = {1 -- 1}, year = {2022}, abstract = {Hochreflektierende Metallbeschichtungen sind essenziell f{\"u}r zahlreiche optische Elemente. Bew{\"a}hrte Spiegelbeschichtungen aus Silber und Gold bieten eine hohe und breitbandige Eigenreflexion im infraroten Spektralbereich, sind ohne geeignete Schutzschichten jedoch anf{\"a}llig gegen{\"u}ber Umwelteinfl{\"u}ssen und mechanischer Beanspruchung. Insbesondere im langwelligen Spektralbereich verringern die Absorptionsbanden dieser Schutzschichten teilweise die hohe Spiegelreflektivit{\"a}t wieder. Das Edelmetall Iridium (Ir) ist hart; extrem dicht; thermisch, mechanisch und chemisch stabil; weist eine {\"a}hnlich hohe Reflektivit{\"a}t im mittleren und fernen Infrarot, wie Silber und Gold, auf und hat zus{\"a}tzlich eine hohe Best{\"a}ndigkeit gegen{\"u}ber Umwelteinfl{\"u}ssen - auch ohne Schutzschichten. In diesem Beitrag werden die optischen und strukturellen Eigenschaften von Iridium-Spiegelbeschichtungen, welche mittels Atomlagenabscheidung (ALD) und DC-Magnetron-Sputtern hergestellt wurden, vorgestellt und miteinander verglichen. Die komplexen Brechungsindizes f{\"u}r ALD-erzeugte und gesputterte Iridium-Spiegelbeschichtungen wurden f{\"u}r Wellenl{\"a}ngen von 200 nm bis 20 μm bestimmt, welche nun bereits vorhandene Literaturwerte erg{\"a}nzen.}, subject = {Iridium}, language = {de} } @misc{HudecGilleGuimbelotetal.2022, author = {Hudec, Rene and Gille, Florian and Guimbelot, Elzear and Tichy, Vladimir and D{\"o}hring, Thorsten}, title = {Effective areas of astronomical X-ray optics for cubesats and rocket experiments}, publisher = {DGaO}, organization = {TH Aschaffenburg}, pages = {1 -- 1}, year = {2022}, abstract = {We address the problem of estimation the sensitivity of astronomical X-ray telescopes of Lobster Eye type , with emphasis on calculation of effective areas for telescopes designed for rocket and CubeSat flights. This parameter is one of the principal parameters when justifying the real space application. Indeed, the larger the effective area is, the more efficient the optical system is, able to provide images of fainter and more distant celestial targets. We discuss the estimation of the effective collecting area of a X-ray telescope by two different methods and then compare the results: the analytical method and then the simulation algorithm.}, subject = {R{\"o}ntgenteleskop}, language = {en} } @inproceedings{DoehringStollenwerkSchmittetal.2022, author = {D{\"o}hring, Thorsten and Stollenwerk, Manfred and Schmitt, Paul and Szeghalmi, Adriana}, title = {Environmentally stable iridium mirror coatings for the infrared spectral range}, series = {Proceedings of SPIE}, volume = {2022}, booktitle = {Proceedings of SPIE}, number = {12298}, publisher = {SPIE}, organization = {TH Aschaffenburg}, doi = {https://doi.org/10.1117/12.2632057}, pages = {122980A-1 -- 122980A-08}, year = {2022}, abstract = {Highly reflective metal coatings are essential for numerous optical elements. Established mirror coatings made of silver (Ag) and gold (Au) offer high and broadband self-reflection in the infrared (IR) spectral range but are susceptible to environmental influences and mechanical stress without suitable protective layers. In the long-wavelength spectral range, in particular, the absorption bands of these protective layers partially reduce the high mirror reflectivity again. However, the noble metal iridium (Ir) is hard, extremely dense, and thermally, mechanically, and chemically stable. Iridium provides a similarly high reflectivity in the mid (MIR) and far-infrared (FIR) spectral range, as silver and gold, and high resistance to environmental influences - even without protective layers. In this paper, the different deposition processes, as well as the optical and structural properties of iridium mirror coatings fabricated by atomic layer deposition (ALD) and by magnetron sputtering (MS), are presented and compared with each other. The complex refractive indices for ALD and MS deposited iridium mirror coatings were determined for wavelengths from 200 nm to 20 μm, complementing the existing literature values. We demonstrate that iridium mirror coatings offer a high and broadband reflectivity from the mid to far-infrared spectral range. In contrast to established - protected - silver and gold mirror coatings, the iridium coatings are environmentally durable and thermally stable up to 600 °C, even without protective layers. Therefore, as an interesting mirror coating material, iridium has the potential for special applications in infrared astronomy and probably also for industrial instruments.}, subject = {Iridium}, language = {en} } @inproceedings{DoehringStieglitzHudecetal.2022, author = {D{\"o}hring, Thorsten and Stieglitz, Veronika and Hudec, Rene and Sapsai, Iryna and Friedrich, Peter and Burwitz, Vadim}, title = {Characterization of a lobster-eye type X-ray telescope}, series = {EOSAM-Conference}, volume = {2022}, booktitle = {EOSAM-Conference}, organization = {TH Aschaffenburg}, pages = {1 -- 1}, year = {2022}, abstract = {Lobster-eye type X-ray telescopes use reflecting plano mirrors under grazing incidence and can observe a large field of view. As part of a Bavarian-Czech cooperation, two telescopes were build, equipped with mirrors coated with gold and iridium. Their X-ray characterization was carried out at the PANTER test facility, which simulates parallel starlight incident on the telescopes. The telescopes have an angular resolution of about 4 arc minutes in X-rays and a focal length of about 2 meters. The used X-ray mirrors reflect and focus visible light as well; their functionality in the optical regime was checked in laboratory tests. Now another test campaign will be carried out to examine the telescope resolution for real objects of the visible night sky and the imaging properties for star constellations.}, subject = {R{\"o}ntgenteleskop}, language = {en} }