黑体辐射源作为初级标准, 其辐射特性的测量精度决定了整个标准传递链路的不确定度。为了提高黑体的辐亮度测量精度, 研制了一台可直接观测黑体辐亮度的双通道热红外标准辐亮度计。根据仪器的工作原理, 采用自行研制的高精度水浴黑体获取标准辐亮度计的定标系数。实验结果表明, 该辐亮度计的1 h信号非稳定性优于0.3%, 定标系数拟合不确定度优于1.23%, 5 μm通道整体不确定度为0.39%, 10 μm通道整体不确定度为1.3%。可实现黑体辐亮度与实验室辐射标准之间的传递。

Blackbody radiation source as a primary standard, its measurement accuracy determines the uncertainty level of the whole traceability link. To improve the measurement accuracy of blackbodies′ radiance, a double-channel thermal-infrared standard radiometer was developed. According to the principle of the instrument, calibration coefficients of the standard radiometer were obtained by using a high accuracy water-bath blackbody. Experimental results suggest that the radiometer′s instability is less than 0.3% within one hour, uncertainty of fitting coefficient is less than 1.23%, and combined uncertainty is less than 0.39%, 1.3% in 5 μm and 10 μm channel respectively. This radiometer provides new means for tracing blackbody radiance directly to radiant standard in lab.