Study On Quantum Dot Filter Array

The ever-increasing development of optics has brought more and more convenience and efficiency to people’s lives.With the development of these optical industries,the demand to filters has also been advanced and diversified.Currently,filters have important applications in military,optical communications,biomedical,spectral analysis,and satellite remote sensing.The current filter ismostly an interference filter,which is composed of a complex film system.In contrast,the absorption filter has the advantages of simple manufacturing process,low cost,and insensitivity to incident angle.However,the absorptive filter also has a low cutoff rate,and when the material of the absorptive filter is determined,the cutoff wavelength of the absorptive filter is also determined,that is,the drawback that the cutoff interval is not tunable.Based on this,we propose that we can apply the size-dependent property of quantum dots,using a material or a limited number of materials to produce longwavelength cut-off filters with different cut-off wavelengths,which has great research value.At present,there are few reports on colloidal quantum dot absorption filters,and the reports of micro quantum dot filter arrays are almost blank.This paper utilizes the efficient light absorption properties of colloidal quantum dots and the tunable first exciton absorption peak wavelength.A tunable micro-absorption cut-off filter array was fabricated,tested and analyzed.The main contents are as follows:(1)Preparation and characterization of CdS quantum dots,CdSe quantum dots and CdTe quantum dotsIn this paper,the required CdS quantum dots,CdSe quantum dot,CdTe quantum dot nanocrystals were prepared by thermal injection method,and their absorption spectra,luminescence spectra,XRD patterns and TEM micrographs were measured and analyzed,the effect of p-phenylenediamine on quantum dot absorption and luminescence was verified..According to the absorption spectrum correlation data of the quantum dots,the particle size and extinction coefficient of the quantum dots were calculated according to the fitting formula.Important characteristics of quantum dot size dependence have been discovered,and the value of the molar extinction coefficient reflects the maximum value of light absorption.Based on these characteristics,we provide ideas for making absorption quantum dot filters.(2)Research on the fabrication and performance of quantum dot filtersIn this paper,after a series of processing on CdS quantum dots,CdSe quantum dots and CdTe quantum dots,it is used as a material for the tunable absorption quantum dot filter with cut-off wavelength.After adjusting the absorbance of quantum dots,an ideal long-pass cut-off filter was fabricated,and the transmittance curve was analyzed in depth.The correspondence between the cutoff wavelength and the first exciton absorption peak of the quantum dot was found.It provides new ideas for the future of absorbing filter fabrication.(3)Fabrication of miniature quantum dot filter arraysUsing the sonopolt system,after fine adjustment of the concentration and tremor voltage,a quantum dot array with uniform gap and good film formation quality was fabricated.