Micro-structure color wavelenght division device

摘要

A color image display element having a color wavelength division device. The color wavelength division device contains a light transmitting three-dimensional microstructure formed on a two-dimensional surface, said two-dimensional surface being a surface of a transparent substrate. The three-dimensional microstructure is made to have a localized light-diffractive profile such that white light of an incident backlight source will be divided into wavelengths of red, green, and blue, and these red, green, blue wavelengths will be respective focused at a target projected plane. In a preferred embodiment, the localized light-diffractive profile of the three-dimensional microstructure is calculated using an iterative approach in conjunction with the following equation: $U_2\left(x,y\right)=\frac{e^{i\mathrm{kz}}}{i\mathrm{lambda}z}{e}^{i\frac{\mathrm{pi}}{\mathrm{lambda}z}\left(x^2+y^2\right)}\int {\int }_{-\infty }^{+\infty }{U}_1\left(\mathrm{xi},\mathrm{eta}\right)e^{-i\frac{2\mathrm{pi}}{\mathrm{lambda}z}\left(z\mathrm{xi}+y\mathrm{eta}\right)}d\mathrm{xi}d\mathrm{eta}.$