Study On The Key Technology Of Spectral Correction For Micro Spectrometer

Spectrometer,also known as the spectroscopy instrument,is a device that measures the spectral intensity at different wavelengths in the spectrum using a photodetector such as a CCD.It consists of an entrance slit,a dispersion system,an imaging system,and an exit slit.Dispersive elements such as gratings and prisms separate the electromagnetic radiation of the light source from the desired wavelength or wavelength region and measure the intensity of the selected wavelength.Although traditional spectrometers are relatively accurate,they are too bulky and expensive,limiting their scope of application.For the wider application of spectrometers,miniaturization is an inevitable trend of development.With the development of micro-opto-electromechanical technology,advanced processing technology and computer technology,spectrometers have entered a new stage of automation,intelligence,digitization,and miniaturization,and miniature spectrometers have emerged.At present,the micro-spectrometer industry is in a state of rapid development.Although significant progress has been made before,the performance of micro-spectrometers produced by current manufacturing and integration technologies is still not satisfactory,and the measurement spectrum exists by the instrument.Large errors due to error factors such as bandwidth,noise,and stray light.Under the existing micro spectrometer hardware conditions,how to restore the true spectral information to the collected spectral data has always been one of the important issues in the development of spectrometric instruments and has received extensive attention from domestic and foreign experts.The influence of noise,instrument bandwidth and stray light on instrument measurement is analyzed from the physical level.According to the causes of different error factors and the effect on the measurement spectrum,the error factors are classified,and the mathematical models of each error factor are established.The key technology of spectral correction for wavelength location accuracy,CCD linearity,instrument noise,instrument bandwidth and stray light is explored based on the mathematical model established.A LED color measurement system based on micro spectrometer is built.The standard light source is traced to the source NIST,and the samples to be measured are four different white light LED beads and red,green and blue monochrome LED beads provided by Instrument Systems company.The sample measurement parameters provided by the company are taken as reference standard values.On the basis of fully understanding several key technologies of correction,a spectral preprocessing and correction pipeline for LED color measurement system has been built innovating.The LED spectrum data were corrected by pretreatment before and after correction,and the color parameters were calculated separately and compared with the standard parameters.Before the LED spectrum is pretreated,the difference between the color coordinates and the real value is about 0.003.The difference between the color coordinates and the real value is about 0.001 and the accuracy has been greatly improved after the pretreatment of the pipeline.Experimental results verify the effectiveness of spectral preprocessing for correcting pipelines.