This research project aims at making very compact compound optical systems with total system thickness and focal lengths in the order of millimetres, using microlens arrays. Microlens arrays are thin, usually planar lenses composed of much smaller lenslets with diameters in the order of hundreds of microns or smaller. Using microlens arrays, optical systems can be composed of a couple of “sheets” of microlens arrays, which would greatly reduce the thickness of the optical systems compared to optical systems made using singlet lenses with same optical power.