Wavelength calibration needs to be done before the spectral measurement of a monochromator. The relationship between the output wavelength and the number of stepping motor pulses of Czerny-Turner double grating monochromator was derived. Experiments of wavelength calibration were carried out. A low pressure mercury lamp was used to provide characteristic calibration lines at ultraviolet and visible wavelength range, spectrum scanning was done by the monochromator to get the data of signal intensity versus indicated wavelength. Finite wavelength correction was computed from the data. Then correction at arbitrary output wavelength ranging from 250nm to 450 nm could be obtained using curve fitting. The wavelength calibration insured the accuracy of the monochromator wavelength.%单色仪在实际光谱测量前需要进行波长校准.文中分析了波长驱动原理,并推导了Czerny-Turner双光栅单色仪出射波长与步进电机脉冲数的关系式.在此基础上进行了波长校准实验.使用低压汞灯作为校准光源,在紫外波段和可见波段蓝端,扫描多条低压汞灯特征谱线,得到单色仪的指示波长与信号强度的关系数据.计算出单色仪出射这些谱线时使用的波长修正量.最后使用曲线拟合方法得到250 nm～450 nm光谱范围内单色仪出射任意波长时对应修正量的计算式.波长校准保证了单色仪的波长准确性.
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