A bench-joining optical component and a first optical component are aligned on a first optical bench, and then rigidly coupled to the first bench, in order to form a first portion of an optical subassembly. Following completion of the first portion, all components in the first portion are pre-aligned and fixed with respect to each other, moving as a unit. A third optical component is aligned and permanently coupled to a second optical bench, in order to form a second portion of the optical sub-assembly. The first and second portions of optical sub-assembly are combined by positioning an exposed side of the bench joining optical component on the second bench, aligning the bench-joining optical component with the third optical component on the second bench, and permanently securing the bench-joining optical component to the second bench.