Plasmon Nanostructure Tunable Color Filter

The color filter is an optical element that can selectively pass or block light at a specific wavelength,thereby changing the color of the light.It is widely used in many fields,such as display technology,optical communication and medical imaging.Therefore,the study of color filters has always been a topic worthy of further exploration.These color filters have the advantages of high resolution,good stability and strong anti-interference ability.With the development of modern equipment towards miniaturization,integration becomes more and more difficult.However,the emergence of nanostructured color filters has largely solved this problem.In this paper,two types of color filters,plasma and all-dielectric,are designed by finite-difference time-domain method.The main research work and innovations are as follows :1.In order to solve a series of color filtering problems such as low resolution,color vividness and low transmission efficiency in color display,this paper proposes a high transmission efficiency color filter with polarization insensitive super selectivity.It uses a double-layer plasma subsurface structure.The thickness of this structure is very small,which is beneficial to the coupling between layers and layers.The characteristics of various aspects are systematically studied.The results show that the transmission efficiency of the coupled double-layer subsurface structure is 9.5 % higher than that of the early single-layer design.The color filter in this paper has the characteristics of polarization insensitivity,low bandwidth of 25 nm and high transmittance of 0.903 in the visible light range.2.In order to solve the problems of color stability,device size and color reproducibility of traditional colorants,this paper proposes a plasma blue filter with symmetrical arc hole structure.Due to the circular hole structure of metal Al and its coupling with its oxide medium under the irradiation of light,the momentum between photons and plasma is better matched,so that when the light passes through the metal film,the metal and surface produce surface plasmon resonance.While obtaining different transmission spectra,high saturation and high resolution blue are obtained,so as to realize the blue filter desired in this paper.3.In order to solve the problem that the existing colorants and filters only output one color,and the saturation and resolution of the color are not very good,this paper proposes a wide color gamut super-selective reflective color filter.Due to the high loss of metal in the visible light band,the efficiency of the plasma color filter may be limited.In order to solve this limitation,an all-dielectric color filter based on Mie principle is adopted in this paper.While obtaining high-quality color,it also has low loss at visible light band frequency.By changing the structure size and period size,the characteristics of wide color gamut and high reflectivity,as well as 12 nm low full width at half maximum and 50.75 high quality factor are obtained.