对等离子体温度的测量能间接诊断瞬态物理场的瞬时温度变化。使用望远光学系统对准等离子体并收集其光谱。光栅分光系统高精度地（Δλ<0.1 nm）分离提取出测量所需的等离子体四通道特征光谱信号。光纤将光谱信号导入高灵敏度、快速响应的光电倍增管（PMTs,采集时间小于1 μs）, 达到瞬态测试的要求。用四通道数据拟合Boltzmann直线提高了计算激发温度的精度（优于2%）, 同时从黑体辐射理论推导出等离子体辐射温度的计算模型。只需用一次测量得到的光强就可以同时得到等离子体的激发温度和辐射温度。利用标准温度灯对系统的光谱响应系数进行了标定, 通过实验表明系统测温的精度优于3％。

Variation of the transient temperature of transient physical field can be diagnosticated indirectly by measuring the temperature of the plasma. Spectrum of the plasma is gathered by the telescope which is the prepositive optical device of the system. Four characteristic spectral signals from the atom excitation are separated accurately (Δλ<0.1 nm) from the light of the plasma by the diffraction grating. Photomultiplier tubes (PMTs) with high sensitivity and short response time (＜1 μs) detect the four signals through the optical fiber, for satisfying the request of the transient measurement. Calculation precision （better than 2%） of the excitation temperature is increased by fitting Boltzmann line with four data. Computational model of the radiation temperature is deduced based on Planck’s blackbody radiation theorem. Transient excitation and radiation temperatures of the plasma are calculated isochronously by measuring light intensity once. Modulus of the spectral response of the system is calibrated by standard lamp. The results of the experiment show that the precision of the system is better than 3%.