紫外光谱辐射定标中的漫反射板反射特性研究

建立了紫外波段漫反射板双向反射分布函数的测量装置，研究了在特定接收条件下铝漫反射板双向反射分布函数(BRDF)随入射角的变化，并对测量误差作了相应的分析，漫反射板定标的相对精度小于2.5％。测量了铝漫反射板从250～650 nm的半球反射比。随着波长的增加，铝漫反射板的半球反射比略呈上升趋势，在紫外探测仪的探测波段300～360 nm之间变化约6%。监测了铝漫反射板的半球反射比随时间的长期变化。铝漫反射板在制备一年后，其半球反射比基本保持稳定，在紫外探测仪的探测波段300～360 nm范围内，其半球反射比平均下降约0.9％。

The Study of Aluminium Diffuser Calibration in the UV

A bi-directional reflectance distribution function(BRDF)measurement setup in the ultraviolet spectral range was established.The BRDF of the aluminium diffusers at a given orientation was measured.The relative accuracy of the BRDF measurement is better than 2.5%.The hemispheric reflectance of the aluminium diffusers was measured in the wavelength range from 250 to 650 nm.It increases with the wavelength,and changes about 6% from 300 to 360 nm.It decreases with the time.Since the diffuser was made(about one year ago),from 250 to 300 nm,the peak decrease in the hemispheric reflectance can reach 2.6%,and the average decrease is 1.5%.From 300 to 360 nm,it has an average decrease of 0.9% decrease,and 0.8% when wavelength is longer than 360 nm.