An optical assembly includes a solid spacing layer between a plenoptic microlens array (MLA) and a pixel-level MLA, avoiding the need for an air gap. Such an assembly, and systems and methods for manufacturing same, can yield improved reliability and efficiency of production, and can avoid many of the problems associated with prior art approaches. In at least one embodiment, the plenoptic MLA, the spacing layer, and the pixel-level MLA are created from optically transmissive polymer(s) deposited on the photosensor array and shaped using photolithographic techniques. Such an approach improves precision in placement and dimensions, and avoids other problems associated with conventional polymer-on-glass architectures. Further variations and techniques are described.