Research On Polarization And Fluorescence Characteristics Of Plants And Design Of Imaging System

At present,plant stress analysis is of great significance to agriculture and environmental ecology research.Polarization imaging and plant chlorophyll fluorescence imaging detection also have the advantages of non-invasion and non-destructive.The application of chlorophyll fluorescence imaging to evaluate the health status of plants is relatively mature,and the polarization information generated by plant leaves can also effectively reflect their own characteristics.Based on this,the potential of plant fluorescence polarization imaging in physiological stress was explored by combining plant polarization imaging with chlorophyll fluorescence imaging in this thesis.Based on Stokes polarization imaging,Mueller matrix polarization imaging and plant chlorophyll fluorescence imaging theory,in this thesis a set of plant polarization and fluorescence imaging detection system is built,the optical system processing and debugging is completed,and the acquisition of fluorescence,polarization and fluorescence polarization combination images can be captured.A set of data processing software is designed based on Qt+OpenCV+Armadillo,and the experimental image processing and polarization parameter curve change analysis are realized.The reliability of the system is verified by experiments.In the aspect of performance analysis,the differences of different plant polarization imaging and fluorescence polarization imaging are compared and analyzed.It was found that some polarization parameters can be used to detect and analyze plant disease spots.The experiments of plant water stress show that the relative parameters of Mueller matrix and the polarization degree of Stokes fluorescence line can be used to represent leaf water content,which pointed out the direction for the quantitative research of plant leaf water content change.At the same time,a plant telemetry imaging system was designed based on the Zemax optical simulation element,which preliminarily realized the acquisition of chlorophyll fluorescence signals in the system,and completed the design and processing of the main mechanical structure of the system.The chlorophyll fluorescence imaging experiment of plants shows that the system has the ability to detect weak fluorescence signal and can be used to monitor plants from the perspective of telemetry.The experimental results show that the design structure of plant fluorescence polarization imaging system and plant telemetry imaging system is reasonable and feasible.The results of polarization and fluorescence imaging measurements are stable and reliable,and it can be used to represent the phenomena such as plant water content.The experimental results of plant fluorescence polarization imaging laid a foundation for the future use of plant telemetry imaging system combined with polarization module to explore plants in natural environment from the perspective of fluorescence polarization.