Research On The Key Technology Of The Miniature Spectrometer And Its Application System

In this paper, we analyzed and researched the national standard JJG178-2007"ultraviolet, visible, and near-infrared spectrophotometer verification regulation". The design standard of the ultraviolet, visible, near-infrared miniature spectrometer is developed. The high-performance and high stability industries level miniature spectrometer design requirements are indicated. Then we used three aspects in circuits, optical mechanic, and software to design and implement the short focal cross asymmetrical Czerny-Turner miniature spectrometer and the long focal cross symmetrical Czerny-Turner miniature spectrometer. Finally, we completed processing, installation, commissioning and performance testing of the two spectrometer systems.We study the micro-spectrometer spectra preprocessing technology in in details. Also, we researched miniature spectrometer to eliminate higher order diffraction spectrum technology, established a theoretical model of the diffraction spectrum order distribution, proposed multi-coating step-type filter design methods, and used innovative optical etching with multiple coating to achieve good experimental results.Based on the diffraction spectral order distribution model, we implemented a method to digitally eliminate high order diffraction spectrum. We use short-wave pass filter with a wide spectrum light source experiments measured the diffraction secondary efficiency ratio of the spectrometer, and we are able to digitally eliminate high order diffraction spectrum. This method has more advantages in spectral efficiency than the method using the above filter method.We proposed a definition of scatter light in the spectrometer, used the simulation software to analyze micro-spectrometer scatter light distribution. The special aperture stop is designed to eliminate scatter light. A quantitative test of the spectrometer scatter light is achieved. We also researched on nonlinear correction method for the miniature spectrometer. The nonlinear gain correction method and light intensity nonlinear correction method is proposed. An innovative method is used to measure the nonlinearity coefficient of the spectrometer with a dual-core optical fiber. We researched on the calibration technology of the miniature spectrometer. The accuracy and drawbacks of wavelength calibration method based on polynomial fitting is analyzed. The pioneering model of the wavelength calibration using the spectrometer system parameters is established. The optimization algorithm is used to calculate the actual spectrometer system parameters, and the wavelength calibration is achieved. The wavelength deviation of the parameter method is enhanced in magnitude. The automatic peak searching method is also developed based on the needs of the wavelength calibration.We researched the absolute radiometric calibration technology of the miniature spectrometer. The influence of spectral resolution and integration time is added into the traditional absolute radiometric calibration model. The Ideal grey-body light source is used to achieve absolute radiation measurement in the miniature spectrometer.The influence of beam structure in spectrometer system to the measurement accuracy is researched and analyzed. Then we designed and implemented a single-beam spectrum detection system based on fiber collimator and miniature spectrometer. The standard solution of potassium dichromate transmittance is measured using this system.Based on the advantages and disadvantages of the single-beam and double-beam spectrometer, a novel double-beam miniature spectrometer is designed and implemented. We creatively used twin-core fiber and the area array CCD detector simultaneously received and displayed the detected reference light and the sample light. The optical design software is used to analyze and design astigmatism eliminating components (cylindrical lens) and dual-beam separation system. The lighting analysis software is used to analyzing the feasibility and accuracy of the dual-beam spectrometer system. Finally, the actual dual-beam miniature spectrometer system is successfully assembled and adjusted. The display and measurement of the double beam is achieved.