Wide angle reflective color filter based on metal-dielectric thin films

In order to improve the characteristics of angular tolerance and light utilization efficiency of color filter,a color filter based on metal-dielectric thin films was designed. Three reflective color filters based on subtractive principle were obtained by membrane system optimization method. The central wavelengths of Cyan,Magenta and Yellow color filters locate at 655 nm,555 nm and 455 nm respectively,and their spectrum bandwidths are 70 nm,60 nm and 60 nm respectively. The proposed color filter owns the feature of high light utilization efficiency because two-thirds of the visual spectrum can be utilized by reflection while only one third is absorbed by the color filter. The measured results demonstrate that the reflective spectrum of this color filter maintains almost constant with the incident angle varied up to ± 40° which satisfies the requirements of characteristic of wide angle. Compared to other color filters,this color filter also owns the characteristic of easy fabrication benefitting from its fabrication technology of films.