An image sensor includes an array of image sensor cells, on a substrate, and a peripheral circuit region extending adjacent the array of image sensor cells. The array of image sensor cells includes a plurality of lens elements and a plurality of color filters extending adjacent the plurality of lens elements. A plurality of photodiodes is provided in the substrate. The plurality of photodiodes are aligned to corresponding ones of the plurality of lens elements. An interconnection structure is also provided, which extends between the plurality of photodiodes and the plurality of color filters. The interconnection structure has an array of cavities therein that are aligned to corresponding ones of the plurality of photodiodes and are filled with a light guide material. The peripheral circuit region includes a metal interconnect pattern and an electrically conductive pad on the metal interconnect pattern. An electrically insulating layer extends on the electrically conductive pad. The electrically insulating layer is formed of the light guide material.