A device includes a semiconductor substrate, a plurality of micro-lenses disposed on the substrate, each micro-lens being configured to direct light radiation to a layer beneath the plurality of micro-lenses. The device further includes a transparent layer positioned between the plurality of micro-lenses and the substrate, the transparent layer comprising a structure that is configured to block light radiation that is traveling towards a region between adjacent micro-lenses, wherein the structure and the transparent material are coplanar at respective top surfaces and bottom surfaces thereof.