Research Of Data Readout Module Based On Fluorescence Micro-Spectrometer

Along with the rapid development of science and technology,the spectrum analysis technology develops at a high rate.In recent years,the spectrometer has been developing towards miniaturization and intellectualization combining with modern microelectromechanical technology and optical fiber technology.It can be designed into a miniaturized equipment with high integration,small volume,simple operation,fast analysis,high precision and wide application.These advantages make the spectrum analysis technology applicable in more fields,such as petrochemical industry,industrial production line,geological exploration,medicine,pharmaceutical,food,etc.Therefore,microspectrometer should have broad market value and development prospect.After profoundly understanding the development status of micro-intelligent spectrometer,this thesis studied the structure and working principle of the spectrometer.Based on the fluorescence spectra and CCD(Charge Coupled Devices)imaging principle,the readout circuit of micro spectrometer was studied and designed.According to the function of readout circuit,the design is divided into four modules: signal acquisition circuit,signal processing circuit,FPGA(Field-Programmable Gate Array)chip circuit and serial port communication interface.The signal acquisition circuit aims to actuate CCD detector.Signal processing circuit realizes signal amplification filtering and AD(Analog to Digital)conversion function.The FPGA circuit module,which is the control core of the readout circuit,provides the driving signal for the CCD detector and the AD chip,and controls the data transmission of the serial communication signal.The serial communication module realizes the function of controlling signal and transmitting spectral data.This thesis selects FPGA as the control chip,and use Altera design software to program logic system design with VerilogHDL language.The program is divided into CCD driver module,AD conversion control module,data cache module and serial port communication module.The CCD driver module realizes the timing control of the time adjustable.AD conversion module is responsible for the control of AD chip and efficient reading of effective signal.The data cache module caches the digital signal of the AD chip and then sends it to the serial communication module.It will further send the upper computer for the processing and analysis of spectral signals.After completing the design work,the PCB sample of the readout circuit hardware was made,and the whole debugging was conducted with the FPGA program part.This design effectively realizes the readout function of CCD signal,and the whole circuit is miniaturized in the size of 70mm×90mm,which conforms to the research and development of microspectrometer.