Design And Optimization Of Optical System For Wide Band Micro Spectrometer

In recent years,the application of spectrometer has become widely used.In addition to spectral analysis in scientific laboratories,spectrometer are becoming widely used in more and more commercial and civil applications,such as industrial monitoring,environmental monitoring and so on.Under this background,the requirements for spectrometer are not limited to higher precision and more functions,and the trend towards miniaturization is also developed quickly according to the demand.Since the 90s of last century,the field of optical devices and microelectronics has entered a rapid development stage,which provides a favorable technical condition for the miniaturization of spectral instruments.At present,a variety of specific micro spectrometer has been introduced in the market,but there are still some problems to be solved in the wide band spectrometer that covers ultraviolet light area,visible light area and near infrared light area.Therefore,it is of great practical significance to study the design method and optimization measures of optical system of wide band micro spectrometer.Firstly,the optical structure of the common micro spectrometer,the symmetrical Czerny-Turner structure and the crossed Czerny-Turner structure are analyzed and compared in detail,and the symmetrical Czerny-Turner structure is chosen as the optical structure of the wideband miniature spectrometer designed in this paper.Then,according to the analysis of the optical parameters,the optical constraint relation is summed up.On this basis,a set of system design method based on optical constraint relation is proposed,and the design and Simulation of optical system are carried out by using ZEMAX simulation software.The influence of the different types of image and difference tolerance on the imaging quality in the optical system is analyzed,and the corresponding mechanical structure is designed to ensure the reliability of the trial optical system.In addition,in view of the two problems caused by broadening the spectrum range:the low ultraviolet response and the introduction of the two level spectral line interference,the reasons for its appearance are analyzed,and the methods of UV enhancement coating and filter are put forward,and the two problems are solved economically and effectively.Finally,the electronic system and software system matching the optical system are designed and the optical system is measured.The measurement results show that the miniature spectrometer designed in this paper can get the resolution of about lnm in the range of 200-1100nm,and realizes the development of a wide band miniature spectrometer.The reliability and reasonableness of the optimization measures taken in broad spectrum.