LED Light Source For Visible And Near Infrared Spectroscopy Detection Of Orange Sugar Content

Visible-near infrared spectroscopy is an important method of rapid and nondestructive detection of orange,it can detect multi composition of orange as the basis of classification.Light source is one of the most important part of visible-near infrared detection system,this paper comes up with an improved spectrum detection system basing on research of the disadvantage of traditional visible-near infrared spectrum detection system and LED source,and in order to testing the performance of this system,this paper uses "Gongchuan" oranges as object to do spectrum detection experiment.Main objectives and results were as follows:This paper designs a new system basing on LED integrating sphere light source,this light source can transmit spectrum between 420 to 900nm and the waveform can be controlled,this system can be used for detecting of different samples(small,seedless,pellicular).Experiment of orange sugar contant detection by visible-near infrared spectroscopy is taken and the model is built.The results of PLS model show that perpendicular incidence is the best detection way.R and RMSEP of LED experimental group are 0.83 and 0.63 °Brix,r and RMSEP of halogen tungsten lamp experimental group are 0.88 and 0.54 °Brix,these results show that this system can detect orange suger content successfully.Then CARS,GA,SMLR method is taken and SMLR gets the best result.The optimum wavelengths are 460nm?500 nm?515nm?570 nm?680nm?690nm?740nm?850nm?870nm?880nm?900nm?This paper proposes an improved on line detection system includes LED light source(this source can transmit spectrum between 420 to 1050 nm and can be used in visible and near infrared spectroscopy on-line detection of orange sugar content),spectral acquisition unit,position sensing unit,dark and reference spectrum automatic collection unit.This system can collect dark and reference spectrum automatically and improve the stability of collection.Experiment of "gongchuan" orange suger cantant on line detection by visible-near infrared spectroscopy is taken for testing the system,results show:r and RMSEP of PLS model are 0.84 and 0.51 °Brix,these results show that this system can detect orange suger content successfully.