Optical device and color display unit to correct an angle of visibility, emphasize front brightness or diffusion degree, improve brightness and the performance of angle of visibility, and moreover improve the performance of chromaticity. An optical device is a film-like optical device for angle-correcting light toward a predetermined direction and of two materials whose refractive index difference is at least 0.1 or over, formed so that one material constitutes a plurality of light guide paths having total reflection at the boundary with the adjacent other material, in which the light guide paths are formed so that they are not arranged at equal intervals or they have different cross sections from each other and the ratio of the width or diameter of the light input portion of each of the light guide paths to the film thickness of an optical device is at least 1:10 or more.