| In recent years,the technology of mid infrared spectroscopy has developed rapidly.The traditional mid infrared spectrometer has the defects of complex structure,large volume and poor portability.Therefore,it cannot measure the mid infrared spectrum at anytime and anywhere.According to these problems above,a portable mid infrared spectrometer to meet the needs of technology development.This spectrometer is based on linear gradient filter technology.And it has the characteristics of fast measurement,nondestructive measurement and portability.It contains independent sampling port,light source and detector and can provide a more compact,fast and extensible alternation for the traditional Fourier spectrometer.This mid infrared spectroscopy can be applied to chemical identification,food and flavor analysis,environmental testing and scientific research.First,the development of mid infrared spectroscopy is introduced in the first chapter.This spectroscopy plays an important role in many fields in the future.Then the characteristics of several commonly used infrared spectrometers are analyzed.Based on the background of mid infrared spectroscopy,the main content of this paper is presented.In the second chapter,the global optical design of the mid infrared spectrometer is introduced.The basic structure is provided,including MEMS transmitter,linear gradient filter,attenuated total reflection crystal and 128 pixel thermoelectric array.The structure design with Solidworks software and the real picture of the spectrometer are discussed.The third chapter mainly involves the circuit modules of the spectrometer,including MEMS driver module,AD conversion circuit design,data communication module.The design details of the each circuit scheme is given.In the fourth chapter,according to the requirements of the spectrometer,the driver software of the spectrometer and the Android client are compiled.It can satisfy the functions of background light measurement,spectrum acquisition and data saving.In the fifth chapter,in order to investigate the practical effect of the spectrometer,the stability of the instrument is tested.The preliminary test experiments on potassium nitrate and milk are carried out respectively,which verify the practicability of this spectrometer. |
