To improve a color shift phenomenon accompanying an increase in viewing angle and to minimize a decrease in transmittance of light incident from the front.

An optical filter for reducing color shift in a display device includes a background layer formed by laminating a light-transmitting material and a light-diffusing pattern formed over the background layer to diffuse light. The light-diffusing pattern is a thin film coated with light-diffusing particles along the cross section of the background layer in the depth direction thereof, the light-diffusing particles being light-diffusing particles having a green wavelength-absorbing color, which absorbs light having a wavelength ranging from 510 to 560 nm, light-diffusing particles having a cyan wavelength-absorbing color, which absorbs light having a wavelength ranging from 480 to 510 nm, and light-diffusing particles having an orange wavelength-absorbing color, which absorbs light having a wavelength ranging from 570 to 600 nm.