A light sensor cell includes a photosensitive element, a floating diffusion region, and a gate oxide disposed between the photosensitive element and the floating diffusion region. The gate oxide has a non-uniform thickness, with a greater thickness near the photosensitive element and a lesser thickness near the floating diffusion region. A transfer gate is disposed on the gate oxide. The transfer gate has a non-uniform threshold voltage, with a greater threshold voltage near the photosensitive element and a lesser threshold voltage near the floating diffusion region.