The present disclosure relates to optical systems and methods of their manufacture. An example optical system includes a lens assembly having at least one lens. The lens assembly defines an optical axis, a focal distance, and a corresponding focal plane. The optical system includes a substrate having a first surface and an image sensor attached to the first surface of the substrate. The optical system also includes a sensor holder attached to the first surface of the substrate. The sensor holder positions the image sensor along the optical axis and substantially at the focal plane. The optical system includes a registration body having a first registration surface and a second registration surface. The lens assembly is coupled to the first registration surface and the sensor holder is coupled to the second registration surface.