Mass production of integrated optical subsystems may be realized by aligning first and second plurality of dies. The aligned dies are then treated to secure them together. The secured dies are then separated to form a secured pair of dies containing at least one optical element, thus forming an integrated optical subsystem. A bonding material may be provided over at least part of the optical path of each first die, over an entire surface of the wafer or around the perimeter of each first die. Either one of the first or second dies may be provided on a wafer. Either die may contain active elements, e.g., a laser or a detector. The optical elements may be formed in the die or may be of a different material than that of the die.