Patent ID: 7808023

Claim:
An imager comprising: an array of pixel sensor cells formed at an upper surface of a substrate; and a light transmissive layer having at least one diffraction grating formed therein, the diffraction grating being formed over at least one of the pixel sensor cells, wherein the diffraction grating comprises a plurality of periodically spaced grating stripes formed of a material having a different refractive index than a refractive index of a material of the light transmissive layer, and wherein the diffraction grating has a grating period that is between a long-wavelength component and short-wavelength component of incident light causing the diffraction grating to: diffract the long-wavelength light component, having a wavelength greater than the grating period of the diffraction grating, into the 0 th diffraction order such that the diffracted long-wavelength light component is collected by a photosensor corresponding to one of the array of pixel sensor cells that is directly underneath the diffraction grating, and diffract the short-wavelength light component, having a wavelength less than the grating period of the diffraction grating, into higher diffraction orders such that the diffracted short-wavelength light component is collected by photosensors corresponding to those of the array of pixel sensor cells that are immediately adjacent the photosensor that is directly underneath the diffraction grating.