中文摘要：

针对探月二期工程中的有效载荷之一极紫外相机中的多层膜光学元件反射率测量的需要，搭建了一台使用液体靶激光等离子体光源的小型软X射线一极紫外波段反射率计。该反射率计主要由激光等离子体光源、Mcpherson247动狭缝掠入射单色仪及相关的数据采集系统组成。单色仪工作波段为1～125nm，光谱分辨率〈0．08nm。无碎屑的液体靶激光等离子体光源的使用避免了光学元件的损坏，而动狭缝掠入射单色仪的使用则提高了光谱分辨率和波段范围。使用该反射率计实测了工作波长为13．5nm和30．4nm的Mo／Si多层膜的反射率，测量结果表明测量重复性优于±0．5％，实现了对多层膜反射率的高精度测量。

英文摘要：

A compact soft X-ray and Extreme Ultraviolet （EUV） reflectometer system using a Laser Produced Plasma （LPP） light source with liquid-jet target was developed to use in high-precision reflectance measurement of multilayer mirrors in an EUV imager for a payload of CHANGE project. This reflectometer is mainly composed of a LPP light source, a Mcpherson 247 type grazing-incidence monochromator with moving exit slit and a correlative data collection system. The wavelength range of monochromator is 1-125 nm and the spectral resolution is less than 0.08 nm. Compared with metal target LPP source, this reflectometer can avoid destroying optical elements near the light source by using debris-free liquid-jet target, and can improve both wavelength range and spectral resolution by using grazing-incidence monochromator with moving exit slit. At the same time, the reflectances of Mo/Si multilayer coating at central wavelength of 13.5 nm and 30.4 nm were measured,the results show the repeatability of the reflectance measurement is better than ± 0.5 %, which proves that the reflectometer can take high-precision reflectance measurements for multilayer coating mirrors.