An image sensor with embedded wells for accommodating light emitters includes a semiconductor substrate including an array of doped sensing regions respectively corresponding to an array of photosensitive pixels of the image sensor. The semiconductor substrate forms an array of wells. Each well is aligned with a respective doped sensing region to facilitate detection, by the photosensitive pixel that includes said respective doped sensing region, of light emitted to the photosensitive pixel by a light emitter disposed in the well. The image sensor further includes, between adjacent doped sensing regions, a light-blocking barrier to reduce propagation of light to the doped sensing-region of each photosensitive pixel from wells not aligned therewith.