From Event: SPIE Optical Engineering + Applications, 2018
High angular-resolution imagery (~1” or better) together with good off-axis scattering performance (<1/1000 of the PSF peak at 10” off-axis position) are essential ingredients for revealing energetic plasma processes ongoing in the solar corona during flares. However, imagery of the corona has never been performed with such performance due to severe technical difficulty in fabricating precision Wolter mirrors with a wide field of view exceeding several 100”.
We are attempting to realize Wolter mirrors with the above-mentioned performance for future X-ray observations of the Sun. The attempt includes fabrication of engineering mirrors of segmented type to which state-of-the-art precision polish and measurements are applied, followed by X-ray evaluation of focusing performance using BL29XUL parallel X-ray beam line at SPring-8 synchrotron facility. Results of the evaluation are then fed-back to polish/measurements for the subsequent mirrors.
Thus far we have successfully fabricated an engineering mirror whose Wolter surfaces 32.5mm x 10mm each for the parabola and hyperbola segments. The mirror focused 8 keV X-rays with the PSF core size ~0.2” HPD (~0.1” FWHM) and with ~3 x 10^(-4) scattering level at 10” off-axis position. Effort has currently been made to increase the area size of the Wolter surfaces towards application to space-borne optics for solar X-ray observations.
Status of the current development on the precision Wolter mirrors will be reported together with some future prospects.
Conference Presentations are recordings of oral presentations given at SPIE conferences and published as part of the proceedings. They include the speaker's narration with video of the slides and animations. Most include full-text papers. Interactive, searchable transcripts and closed captioning are now available for most presentations.
Search our growing collection of more than 18,000 conference presentations, including many plenaries and keynotes.