An integrated image sensor may include adjacent pixels, with each pixel including an active semiconductor region including a photodiode, an antireflection layer above the photodiode, a dielectric region above the antireflection layer and an optical filter to pass incident luminous radiation having a given wavelength. The antireflection layer may include an array of pads mutually separated by a dielectric material of the dielectric region. The array may be configured to allow simultaneous transmission of the incident luminous radiation and a diffraction of the incident luminous radiation producing diffracted radiations which have wavelengths below that of the incident radiation, and are attenuated with respect to the incident radiation.