Research On Key Technologies Of Visible-Near Infrared Micro-spectrometer

As the basic equipment for analyzing and measuring the composition and structure of substances,spectrometer is widely used in many fields such as food quality testing,science education and aerospace remote sensing.Highly developed micro-nano optical technology and micro-electromechanical systems(MEMS)has miniaturized the traditional bulk spectrometer and makes the compact spectrometers possible,which are widely used due to their merits such as portability,low cost and feasibility of on-chip integration.This article takes the key technologies of visible light near-infrared micro-spectrometer as research topics,and researches its market prospects and development status at home and abroad.Spectrometer system that meets design requirements is designed and built.The main research content of this paper is divided into the following parts:Chose suitable structure after comparing various micro spectrometer structures and analyzing its advantages and disadvantages.Optimizing the simulation design of each device parameter of the spectrometer system according to the design indicators,and select the device model according to the design parameters.The hardware circuit module of micro spectrometer has been developed.The hardware circuit uses Cyclone FPGA as the main control chip to realize the driving timing control,including communication interfaces,linear array detector,data buffer and the A/D transfer module.The designed hardware circuit module should be integrated as much as possible,so as to miniaturize the volume of the entire spectrometer system.The spectral data filtering,and graphic display were realized;the wavelength of the micro-spectrometer was calibrated,and the advantages and disadvantages of method of polynomial fitting and system parameter calibration was compared.Conversion between position and light wavelength was realized.An algorithm to improve the resolution of the micro spectrometer using inverse convolution is proposed.The low resolution data measured under two different entrance slit widths are used to obtain high resolution limited by the width of one pixel of the detector through inverse convolution.The experimental results show that the final spectral resolution achieved by this method can reach 0.35nm,far exceeding the design index requirements.Three key parameters of the spectrometer experimental system were tested:spectral resolution,spectral range,and system volume.The experimental results show that the experimental volume meets the design requirements and the spectral range is 504-780nm When the resolution is 5nm,the corresponding entrance slit width is 140?m.