| 28 | | || '''19.09.2014''' || '''Ralf-Rainer Rohloff''' || '''Exact metal optics over a large temperature range '''[[BR]] [[BR]]Since long, metal optics are an important part of astronomical instruments. Often [[BR]]diamond turned mirrors of aluminum (Al6061) are used. But it is difficult to polish [[BR]]aluminum. Therefore, the mirror is coated with Nickle Phosphor layer, which can [[BR]]be polished more easily. This is very important at shorter wavelength. But the [[BR]]mirrors deform with temperature changes because of the different coeffient of [[BR]]thermal expansion between aluminum and NiP. [[BR]][[BR]]Ralf-Rainer will tell us about a collaboration between MPIA Heidelberg and IOF [[BR]]Jean, which developed and tested a new material to minimize the temperature [[BR]]related deformation of such mirrors. The material consists of an aluminum [[BR]]silicate, which has a coefficient of thermal expansion close to NiP. Thus, the [[BR]]deformation could be reduced drastically. But now the work just started. Is it [[BR]]possible to built a mirror of this material? Does the material change with time? [[BR]]The best answer would be the study could show that such mirror can be built [[BR]]and are stable over time! [[BR]][[BR]]Talk: German [[BR]]Slides: English [[BR]]Questions: German, English || |
| | 28 | || '''19.09.2014''' || '''Ralf-Rainer Rohloff''' || '''Precision metal optics over a large temperature range '''[[BR]] [[BR]]Since long, metal optics are an important part of astronomical instruments. Often [[BR]]diamond turned mirrors of aluminum (Al6061) are used. But it is difficult to polish [[BR]]aluminum. Therefore, the mirror is coated with Nickle Phosphor layer, which can [[BR]]be polished more easily. This is very important at shorter wavelength. But the [[BR]]mirrors deform with temperature changes because of the different coeffient of [[BR]]thermal expansion between aluminum and NiP. [[BR]][[BR]]Ralf-Rainer will tell us about a collaboration between MPIA Heidelberg and IOF [[BR]]Jean, which developed and tested a new material to minimize the temperature [[BR]]related deformation of such mirrors. The material consists of an aluminum [[BR]]silicate, which has a coefficient of thermal expansion close to NiP. Thus, the [[BR]]deformation could be reduced drastically. But now the work just started. Is it [[BR]]possible to built a mirror of this material? Does the material change with time? [[BR]]The best answer would be the study could show that such mirror can be built [[BR]]and are stable over time! [[BR]][[BR]]Talk: German [[BR]]Slides: English [[BR]]Questions: German, English || |
