Systems and methods for optical imaging are disclosed. An optical sensor includes: an image sensor array comprising a plurality of pixels; and a collimator filter disposed above the image sensor array, the collimator filter comprising a plurality of light collimating apertures and light blocking material, wherein multiple light collimating apertures of the plurality of light collimating apertures are disposed within a photosensitive area of one of the pixels in the plurality of pixels, and wherein the multiple light collimating apertures are disposed over different portions of the photosensitive area of the one of the pixels.