Multilayer Dielectric Color Filters for Optically Written Display Using Up-Conversion of Near Infrared Light

An optically written display based on up-conversion of near-infrared light is a newly emerging display technology. For filtering out unwanted colors from this light generator, multilayer dielectric color filters are designed for red, green, and blue screens, respectively. Layer-symmetric films are used in the designed filters and the conjugate gradient method is used to optimize the design. It is observed that the characteristics of the filters are good in the whole visible wavelength range when the incident angle is less than 40deg. The encompassed color triangle of the display with the color filters is larger than that without the color filters, and images with more saturated colors are obtained.