Several optical systems, based on a combination of lenslet arrays and computer-generated holograms (CGH), are described. They provide full or neighborhood connectivity between arrays of electronic processors, each processor containing one transmitter and N detectors. Some of the system are symmetrical, and therefore bi-directional. Specific designs include a system utilizing reflection-mode modulators that provides reciprocal connections between two planes of processors, and a system requiring sources or transmissive modulators that provides the connections required by a back-propagation neural network with an arbitrary number of layers. We derive expressions governing the lengths of the lenslet-based system and of a previous design based on bulk optics and CGH. The proposed systems require fewer components, less volume, and less alignment than the bulk optics system.