Research On Color Generation Mechanism And Spectral Properties Based On Grating Structural Color

Color is one of the most important human feelings, many factors affecting the color, the main thing is the color with the light changed, so the color and light of the inquiry is a very long-standing issue. Color in large areas can be divided into two categories:pigment color and structure. Formation of pigment color is depend on pigment formation of selective absorption of light. The formation of pigment color paint choice is to rely on light waves absorbent formation. Compared to the structure of the color pigments and other materials just do not need a special composition structure itself the role of light. Such ordinary color pigment formed not have the advantages:high brightness, high saturation, never fade, iridescent phenomenon, polarization effects, etc., become the focus of the color of the scientific community。In this paper, the principles of electromagnetic FDTD (Finite Difference Time Domain method) based on the theory of color based on the mechanism oi periodic grating structure Secheng microstrueture using FDTD solutions designed with the color characteristics of the "asymmetric grating structure model" further research and analysis of different grating parameters, including the spine long, spine width, height staircase column, staircase column width, number of columns ladder, staircase column spacing, period, and the refractive index of the medium refractive index of the background light incident angle, the color spectrum influence and variation characteristic curve peaks. Then in principle MatlabR2009a FDTD calculated, changes in various parameters affect change, reflectance FDTD calculations to obtain the corresponding spectral curve comparison chart, analyze and optimize the Structure model of grating variation, according to the changes of these parameters to design the "most excellent structure, "and explores the impact of optimal structure "blush nonstructural parameters influencing factors:the cycle, background refractive index medium refractive index, light angle of incidence. Structural Model Design maximum peak, the optical characteristics of reflectance studies, the intensity of the electromagnetic model like.The results show that the special grating microstructures can produce specific structural color. Influence of different design parameters "asymmetric structure model" peak spectral characteristics are not the same. With the gradual increase of the cycle, not the peak value is also proportional to the increase in the peak period of more than 900nm wave began to decrease after the color is mixed color light appears. However, with the increase of the peak value of the cycle of the position within a wavelength range as large offsets. Color hue changed. Background of the refractive index, the lower the spectral reflectance, the spectral peaks shifted to a longer wavelength, when the refractive index of the background exceeds a certain range, the structural color phenomenon will reduce the reflection spectrum with the peak gradually decreases. Structural changes in the refractive index of the medium reflection spectrum resulting fi-om changes in the peak position and the peak reflectance both are more significant. As the material refractive index of medium becomes large, the reflection peak shifted, while reflection peak half-width becomes larger. When the incident oblique incidence, the reflection peak relative to the normal incidence peak redshift, but the half-wave peak width decreases. As the angle of incidence of the reflection spectrum changes (0°-30°) different from the peak position change significantly, that is, when we change the color observed along the axial angle grating structure is not the same. At the same time the study of optical properties of the "optimal structure" show:change the corresponding parameters can be controlled to achieve the color, the so-called color. Above "optimal structure" three-layer sheet structure for presenting colors to make a greater contribution.3 layer sheet has most of the incident light is reflected back, only a few can be a part of the light transmitted through the layer 3 sheets below. "Optimal structure" are in the grating region and the transmission region of large blue area, and in the entrance area of the small area of red, indicating a smaller value if the width of the upper sheet, lower sheet width even reach the upper bound will there is more light energy transmitted through the structure, but the reflectance is low. While for time to study the structure of the simulation model shows that the structure of the former lOfs basically no light is reflected in the 10-20fs time, the structure of most of the light reflection to render colors. Then a straight line is rendered gradually weakened, no longer reflected...