The Optical Characteristic Studies Of Space EUV Solar Telescope

The space observation in soft x-ray and extreme ultraviolet (EUV) region is an important portion of the space astronomy and an effective solar observation method developed increasingly. In this thesis we designed a EUV multi spectrum space solar telescope (EUT) based on the requirement of high angular resolution and wide field of view for solar observations; investigated the transmission performance of EUT; invented a method of EUT pointing calibration on the space orbit and solved the high precision pointing calibration problems; constructed a prototype of 17.1nm telescope, tested the possibility of EUT design, and developed some cutting-edge techniques.EUT is included in 13.0nm, 17.1nm, 30.4nm and 19.5nm four telescopes whose former three telescopes have narrow fields of view of 8.5'x8.5' and high resolutions of 0.5", and the other one has a wide field of view of 85'x85' and a moderate resolution of 5.0" for full solar disk image.EUT is comprised of four pre-filters, four pieces of multilayer optics, four stray light rejection filters, four detectors and a vacuum chamber. Since the special characteristics of EUV components, the imaging quality and the transmission are severely restricted by the components of EUT. Some filters have been designed for EUT after the studies of the materials absorbing performance in EUV range. We optimized a 13.0nm filter with 70% transmission composed of a sandwich structure of Si-Zr-Si layers. The other three filters are aluminum film with the transmission between 45% and 65%. The mirrors with different multilayers, their characteristics and influence with incidence, have been studied to improve the transmission in the system in which transmission efficiency of the system was calculated.For realizing high precision pointing calibration on the space orbit, we studied some treatment methods of the solar pictures, built up a math model, made a calculation program and dealt with some simulation solar images. The direction deviations between different telescopes are calibrated. In order to approach above target, we applied a VUV filter on the pre-filter wheel with high transmission in solar Ha line. The solar VUV radiation reaches detectors through the filter. Then the solar Ha images are obtained by each telescope. The deviation angle between different telescopes is found out by comparing the images from the different telescopes and the calibration of the solar point deviation is realized.For testing the cutting edge techniques, we developed a prototype of telescope which has a narrow field of view of 8.5'x8.5' and high angular resolution of 0.5". The prototype is made by a concave sphere primary and a plane secondary deposited the Mo/Si multilayer on the fused quartz substrates. The reflectivity peak and the reflectivity uniformity of the multilayer mirrors are respectively 25% and around +2.5% at 17.1nm.