Transmission type color filter and preparation method thereof

The present invention provides a transmission type color filter and a preparation method thereof. The transmission type color filter comprises a base material layer (1); a first metal layer (2), a dielectric layer (3) and a second metal layer (4) are sequentially arranged on the base material layer (1); the thickness of the dielectric layer (3) is T; the refractive index of the dielectric layer (3) is N; and N and T satisfy a relational expression that N*T>=4*lambda/4, wherein lambda is the wavelength of visible light and ranges from 400 to 700nm. The peak transmittance of the transmission type color filter ranges from 60% to 100% at three peaks of RGB, and the transmittance of the transmission type color filter is smaller than 30% at wavelengths of 490nm and 590nm. The three-peak filtering function of the RGB can be realized through a simple three-layer film stack; and the R2R large-scale production of the transmission type color filter can be made possible based on sputtering and coating processes, and the transmission type color filter and the preparation method thereof have broad application prospects.