An image restoration based on a color synthesis method is applied to the color imaging system by the lens with chromatic aberration. Using the continuous-discrete model in which spatial and spectral distribution of the object is considered continuously, the color imaging system with chromatic aberration is mathematically modeled and the technique of reconstructing an arbitrary color band image from the observed color images is present. Moreover, the focus adjustment can be done after the capture of the image by using the proposed imaging system.