NOVELTY - The device (1) is provided with multiple pixels that are made up of photoelectric conversion region, and an optical waveguide (15). The optical waveguide is formed corresponding to the photoelectric conversion region of the pixel. The refractive index of annular core layer (16) of optical waveguide is higher than a portion surrounding the annular core layer, when viewed in a cross-section along a horizontal plane. The refractive index of clad layer (17) surrounded by the annular core layer is lower than refractive index of annular core layer.    USE - Solid-state image sensing device e.g. front and backside illumination type complementary metal oxide semiconductor (CMOS) solid-state image sensing device of electronic apparatus (claimed) such as digital still camera, digital video camera, and cellular phone. Can also be used in charge-coupled device (CCD) solid-state image sensing device.    ADVANTAGE - Since the refractive index of annular core layer of optical waveguide is higher than portion surrounding annular core layer when viewed in cross-section along horizontal plane, the occurrence of crack due to thermal expansion inside the optical waveguide can be prevented, and the efficiency of light collection to photodiode can be increased, due to which quality of the electronic apparatus can be improved. Since the optical waveguide is provided with reflection interfaces between passivation film and the clad layer and between clad layer and the core layer, the number of reflection interfaces can be increased, due to which light loss can be reduced and the efficiency of light collection to the photodiode can be increased. Since optical waveguide enables the incident light to reach the photodiode with higher efficiency, color mixing can be reduced even when the area occupied by the pixel transistors is reduced in device. Since the area occupied by the pixel transistors is reduced and the area of the photodiode is increased, the sensitivity characteristic of the device can be improved.    DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for the following:    (1) method of manufacturing solid-state image sensing device; and    (2) electronic apparatus.    DESCRIPTION OF DRAWING(S) - The drawing shows a cross-sectional view of the solid-state image sensing device.    Solid-state image sensing device (1)    Semiconductor substrate (2)    Optical waveguide (15)    Annular core layer (16)    Clad layer (17)