微型光谱仪辐射定标技术研究

Research on the radiation calibration of micro spectrometer

光谱仪器是进行分析和测量的基本设备,应用非常广泛。由于传统光谱仪的诸多缺点,微型光谱仪成为光谱仪器发展的一个重要的研究方向。作为微型光谱仪主要探测元件的线阵CCD具有实时传输和自扫描速度快、频率响应高、能够实现动态测量且能在低照度下工作等特点,其输出信号为像素点和灰度(DN)值,此输出信号与光谱波长和辐射通量之间的对应关系为定标的主要内容。本文主要研究在假定光谱定标已经完成的情况下,输出DN值与辐射通量之间的定量关系。本文基于拉格朗日插值算法,在Visualstudio平台上利用C#语言编写了辐射定标算法小程序,利用在中国计量院定标过后的钨灯完成了微型光谱仪的辐射定标,消除了因传感器本身产生的误差,并利用未标定的钨灯验证了该定标方法的可行性,且成功应用于微型光谱仪的应用中。

Spectroscopic instruments are the basic equipment for analysis and measurement,and are widely used.Due to the many shortcomings of traditional spectrometers,micro spectrometers have become an important research direction in the development of spectroscopic instruments.The linear array CCD,which is the main detection component of the miniature spectrometer,has the characteristics of real-time transmission and fast self-scanning speed,high frequency response,dynamic measurement and low illumination.The output signals are pixel points and grayscale (DN) values.The correspondence between the output signal and the spectral wavelength and radiant flux is the main content of the calibration.This paper focuses on the quantitative relationship between the output DN value and the radiant flux,assuming that the spectral calibration has been completed.Based on the Lagrangian interpolation algorithm,this paper uses the C# language to write a small program of radiometric calibration algorithm on the Visual Studio platform.The radiation calibration of the micro spectrometer was completed by using the tungsten lamp of the Chinese metrology institute,which eliminated the error caused by the sensor itself,and the feasibility of the calibration method was verified by using the uncalibrated tungsten lamp,and the method was successfully applied in the application of the miniature spectrometer.