采用所研制的紫外辐射照度计余弦响应特性测试平台, 对21种市面上常用的商业紫外辐射照度计进行了余弦响应特性测试。测试结果表明, 不同型号、不同探测器结构、不同漫射器材料的紫外辐射照度计的余弦响应特性差异较大, 客观地反映了当前紫外辐射照度计的水平。当入射角为±10°时, 余弦误差变化范围为0.03%~15.83%;当入射角为±30°时, 余弦误差变化范围为1.85%~73.66%；当入射角为±60°时, 余弦误差变化范围为1.82%~65.04%。在实际测量中, 经常会用到大面积的紫外辐射光源或是形状不规则如长条形的紫外辐射光源, 在测试时不能保证光线垂直入射到探测器, 同时也不能满足点光近似条件, 测试结果误差较大。通过测试可以准确地了解当前紫外辐射照度计的余弦响应特性, 用于指导实际的实验测试, 合理地调整测试条件以满足测试需求, 必要时可进行相应的余弦误差修正。

Through a new designed measurement system for cosine response property of UV radiometers, some measuring experiments are done to 21 kinds of UV meters. The results can well reflect the cosine response property of UV radiometer for different style, different composition of sensors and different kinds of diffuser material. It demonstrates that the cosine response errors exist in all kinds of UV radiometers, and the difference is large, such as when the angel of incident beam is ±10°, the relative cosine error is from 1.85% to 73.66%, when the angel of incident beam is ±30°,the relative cosine error is from 1.85% to 65.04%, and when the angel of incident beam is ±60°, the relative cosine error is from 1.82% to 65.04%. In application, some UV light sources have big surface or are irregular forms, so the incident beam is not perpendicular to the meter surface, and the light sources can not be seen as spot lamps. So it is meaningful to understand the cosine response property of UV radiometers exactly, it can directly adjust measuring condition or do some cosine compensation.