【摘要】 为了提高便携式光栅扫描近红外光谱仪扫描波长的准确性,利用平面衍射光栅的色散公式,结合扫描机构中光栅、摆杆与丝杠之间的位置与传动关系,建立了光谱仪波长修正数学模型,提出了基于粒子群优化算法确定波长修正模型参数、基于波长修正模型的杆长比全谱对比寻优确定杆长和修正参数调节量、对光谱仪施以硬件结构调节软件补偿的波长修正方法,并利用标准光源的特征波长,对自制便携式近红外光谱仪进行了波长修正实验。实验结果表明,经波长修正后光谱仪的波长准确性优于±1 nm,满足光谱仪波长准确性的要求,验证了光谱仪波长误差分析的正确性与修正方法的有效性。更多还原

【Abstract】 In order to improve the accuracy of the scanning wavelength of the portable grating scanning near infrared spectrometer,on the basis of the dispersion formula of plane diffraction grating and the position & mechanical transmission relationship among the grating,swing rod and screw in the scanning mechanism,a mathematical model of spectrometer wavelength correction is built,and a wavelength correction method is proposed. The method includes three processes. First,the parameters of the wavelength correction model are determined based on particle swarm optimization algorithm. Second,the swing rod length and the correction value of the wavelength are determined based on the swing rod length ratio of the wavelength correction model and full spectrum comparison optimization. Third,the hardware structure adjustment and soft parameter compensation are conducted on the spectrometer. The characteristic wavelength of a standard light source was used to perform wavelength correction experiment on the self-developed portable near-infrared spectrometer.The experiment results indicate that after wavelength correction the wavelength accuracy of the spectrometer is better than ± 1 nm,which satisfies the spectrometer wavelength accuracy requirement,and the results verify the correctness of the spectrometer wavelength error analysis and the effectiveness of the wavelength correction method.更多还原