A microelectronic imager having an imaging unit and an optics unit attached to the imaging unit, and methods for packaging microelectronic imagers. In one embodiment, the imaging unit can include a microelectronic die with an image sensor and a plurality of external contacts electrically coupled to the image sensor and a first referencing element fixed to the imaging unit. The optics unit can include an optic member and a second referencing element fixed to the optics unit. The second referencing element is seated with the first referencing element at a fixed, preset position in which the optic member is situated at a desired location relative to the image sensor.