An optical system for generating an image having extended depth of field comprising: a chromatic wavefront coding lens, a phase mask, a processor, and an image sensor, wherein light transmitted through the optical system is focused into an image plane, one surface of the image sensor proximate thereto; wherein the chromatic wavefront coding lens provides axial color separation by providing specified chromatic aberration in an intermediate image incident on the image plane; wherein the phase mask alters the optical transfer function of the optical system to remain substantially constant over a specified range away from the image plane, the specified range exceeding a normal depth of field of an image formed by the optical system having the transfer function unaltered by the phase mask and the chromatic wavefront coding lens; wherein the processor (i) is adapted to convert the intermediate image to a color space including a luminance channel and two chrominance channels, (ii) is adapted to generate a processed luminance channel by filtering the luminance channel with a deconvolution filter corresponding to an inverse of the altered optical transfer function, and (iii) is adapted to combine the two chrominance channels with the processed luminance channel to yield a processed image having an extended depth of field compared to the intermediate image; wherein the optical transfer function of the optical system exhibits an extended depth of field and contains no zeroes within a spatial frequency range limited by pixel-to-pixel spacing of the image sensor, within at least one spectral passband defined by a range of wavelengths passed by a color filter of the image sensor; wherein the at least one spectral passband is one of three said spectral passbands corresponding to a respective color channel of the optical system; and wherein a cross point between two through-focus modulation transfer functions of adjacent color channels is higher than a required minimum modulation transfer function. a chromatic wavefront coding lens, a phase mask, a processor, and an image sensor, wherein light transmitted through the optical system is focused into an image plane, one surface of the image sensor proximate thereto; wherein the chromatic wavefront coding lens provides axial color separation by providing specified chromatic aberration in an intermediate image incident on the image plane; wherein the phase mask alters the optical transfer function of the optical system to remain substantially constant over a specified range away from the image plane, the specified range exceeding a normal depth of field of an image formed by the optical system having the transfer function unaltered by the phase mask and the chromatic wavefront coding lens; wherein the processor (i) is adapted to convert the intermediate image to a color space including a luminance channel and two chrominance channels, (ii) is adapted to generate a processed luminance channel by filtering the luminance channel with a deconvolution filter corresponding to an inverse of the altered optical transfer function, and (iii) is adapted to combine the two chrominance channels with the processed luminance channel to yield a processed image having an extended depth of field compared to the intermediate image; wherein the optical transfer function of the optical system exhibits an extended depth of field and contains no zeroes within a spatial frequency range limited by pixel-to-pixel spacing of the image sensor, within at least one spectral passband defined by a range of wavelengths passed by a color filter of the image sensor; wherein the at least one spectral passband is one of three said spectral passbands corresponding to a respective color channel of the optical system; and wherein a cross point between two through-focus modulation transfer functions of adjacent color channels is higher than a required minimum modulation transfer function.