Spectral Information Acquisition System Based On FPGA

Spectrometer is an important instrument for the physical and chemical composition analysis of matter.However,subject to volume,cost and scanning factors such as the use of traditional spectrometer has been greatly limited,difficult to apply in the project.In the field of industrial measurement and control,automatic measurement and chemical industry,the demand for low-cost and high-performance spectral measurement is increasing.Therefore,it is very important to study the miniaturization,low cost and high-speed development of spectrometer.In this dissertation,after the research and analysis of the existing spectrometer,FPGA is used as the control core,and the linear array CCD is used as a sensor to design a prototype of the spectral information acquisition system.The system is divided into CCD module,signal processing and A /D conversion module,FPGA driver control module,USB communication interface module and PC and other parts of the system in the hardware and software design using a modular design ideas.CCD module using linear array CCD as a sensor for photoelectric conversion;signal acquisition module using AD9226 chip as an analog-to-digital conversion chip to achieve high-speed analog signal conversion;data transmission processing module using USB2.0 interface to ensure high-speed transmission of spectral data;Drive control module using FPGA as the core control components to generate other modules of the control timing signal;PC program using LabView programming,easy to use.After the system is completed,the various components of the system are debugged separately,and the problems of each module in the debugging experiment are analyzed and solved.In addition,in order to fully verify the system performance in this paper,the whole system based on flat-field concave grating of the optical path design and simulation and structures.Finally,the system has carried on the comprehensive experiment,respectively,carries on the calibration experiment to the system wavelength detection and the concentration detection.Experiments show that the system can accurately acquire the spectral data,the accuracy meets the design requirements,and the data reproducibility is good.