在宽动态范围、高分辨力、宽频谱红外辐射测量中，傅里叶变换红外光谱仪（FTIR）是常用的探测单元，其光谱响应度的非线性是宽动态范围红外光谱测量的不确定度主要贡献项之一。基于光通量倍增原理，建立傅里叶红外光谱探测系统的非线性测量实验系统。实验研究了在非线性测量典型时间段内的黑体辐射源和FTIR红外光谱探测系统的漂移特性，设计了测量序列变换模型来消除测量过程中的一阶线性漂移影响。在200~1 000℃范围内，实验测量了FTIR红外光谱探测系统的非线性特征，给出了在典型波长3.9 μm和10.6 μm处的非线性测量结果及相应的不确定度。

In infrared radiation temperature measurements of wide-dynamic, high-resolution and wide-spectrum, Fourier Transform infrared (FTIR) spectrometer is a commonly used measurement unit. The nonlinearity of the spectral responsivity is one of the main uncertainty contributions to wide dynamic infrared spectrum measurements of radiation sources. Based on the flux superposition principle, nonlinearity measurement system of FTIR spectrometer measurement system was established. The experimental research on the drift characteristics of the blackbody radiation source and FTIR spectrometer measurement system during the representative nonlinearity measurement time were carried out. The quasi-linear drift effects on the nonlinearity measurement were eliminated by permuting the aperture measurement order. The nonlinear characteristics of FTIR spectrometer measurement system were experimentally measured at 200~1 000℃. The nonlinearity measurement results and associated uncertainties at 3.9 μm and 10.6 μm are reported respectively.