Development of X-ray telescope with ultra thin mirror substrate machined by diamond turning

我们研究了利用金刚石车削的超薄铝镜衬底研制高通量X射线望远镜。在本研究中，有以下几点需要研究和发展；在镜面基板的制作上，我们采用了金刚石车削加工的方法制作了0.3 mm厚的镜面基板，发现其形状可以达到1.7弧度的HPD性能，同时还发现，通过丙烯酸涂层可以将表面粗糙度降低到1 mm以下。在研制高精度薄箔镜面轮廓仪的基础上，将激光位移传感器与精密Z平台相结合，设计制作了高精度薄箔镜面轮廓仪。该系统已与国内先进的超精密三维柱面镜面轮廓仪系统相连接。为了降低金刚石车削铝箔基板的表面粗糙度，我们还尝试了用非球面抛光技术制作镀镍铝表面的类似镜面。对于这么小的样品镜，我们发现它有足够的光滑表面来制作X射线镜。对于用同样方法制成的Wolter I型镜，其高成像能力得到了证实，因为它具有小于5角秒的小HPD。

We have studied the development of high throughput X-ray telescope using diamond-turned very thin aluminum mirror substrates. In this study, there are following points to research and develop ; production of mirror substrate, production of smooth mirror surface, deposition of metals for X-ray reflecting mirror surface, design and fabrication of mirror support and their alignment mechanics, development of X-ray facility and X-ray measurement for telescope performance.On the fabrication of mirror substrate, we have made 0.3 mm thick mirror substrate made by diamond-turned machining and found that it had the shape to give us 1.7 arcmin HPD performance for 2 stage system and also found the surface roughness can be reduced down to 1 mm by acrylic coating, but X-ray performance is not enough high for low scattering X-ray mirror.On the development of the thin foil mirror profiler with high precision, we have designed and fabricated it assembling laser displacement sensor and precision Z-stage. This system has been connected to the advanced system, namely ultra-precision 3-D cylindrical mirror profiler. To reduce the surface roughness of diamond-turned aluminum foil substrate, we have also tried to make similar mirror with non-spherical polishing technique for nickel coated aluminum surface. For such small sample mirror, we have found that hey have enough smooth surface for X-ray mirror. For Wolter type I mirror made by the same way, its high imaging capability was confirmed as it has small HPD of less than 5 arcsec.