微型紫外光谱仪的非线性校正方法

Non-Linearity Correction Method of Micro-Ultraviolet Spectrometer

微型紫外光谱仪具有定性、定量检测物质的组分与含量的独特优势,被广泛应用于环境监测、医药与食品卫生安全、工农业生产、科学试验等领域。但由于微型紫外光谱仪广泛采用电荷耦合器件(CCD),对光源产生非线性响应。特别是对测量值进行归一化处理时,这种非线性响应行为将极大影响仪器的测量精度。为了减小非线性响应的影响,提出了一种基于最小二乘法的七阶拟合高精度校正方法,并给出各阶校正系数。试验结果表明,经该方法校正后,CCD线性响应度优于99.5%,有效减小了非线性响应的影响,提高了微型紫外光谱仪的测量精度。

Micro-UV spectrometer has the unique advantage of qualitatively and quantitatively detecting the composition and content of substances.It is widely used in environmental monitoring,medicine and food hygiene,industrial and agricultural production,scientific experiments,etc.However,the charge- coupled device (CCD) is widely used in micro- ultraviolet spectrometer and the nonlinear response to the light source is inevitable,especially when the measured values are normalized,the measurement accuracy of the instrument is affected greatly by the nonlinear response.In order to reduce this influence,a high precision correction method with seven- order fitting based on the least square method is proposed and the correction coefficients of each order are given.The experimental results show that the linear response of CCD is better than 99.5%,which can effectively reduce the influence of nonlinear response and improve the measurement accuracy of micro ultraviolet spectrometer.