Analyze On Measuring Error Of Fourier Transform Infrared Spectrometer

Along with the development of computer science, Fourier Transform Infrared Spectrometer (FTIR) is applied in the atmosphere and the oceans, which is getting more and more widespread. And the accuracy of measurement has been becoming increasingly demanding. Therefore, the analysis of the measurement error to optimize the system design is of great significance.The development and the application of infrared spectrometer in our country and abroad are introduced briefly in this paper. Contacting with the working principle of FTIR, it has analyzed each kind of measuring error and the related computation model. The Fourier Transform Infrared Spectrometer's measuring error contains two parts, namely the laser measuring system error and infrared jamming gathering system error. Laser monochromatic and stable frequency characteristic, with each kind of noise determines the optical path difference error and electric signal processing error, thereby influences spectrum measuring accuracy. Through the Fourier inverse transform and the analysis of noise sources, this paper has established the theoretical model between measuring error and laser monochromatic and stable frequency characteristic, also established SNR computer models for each noise. It has carried on the simulation computation, and confirmed that these models can be the theory basis for FTIR design.The paper has further analyzed every kind of error, and obtained system's main error and secondary error. It could provide an effective theoretical basis to select some reasonable measures, which can reduce and eliminate errors.