other with a 0.0007 ??m separation by using a series of 6190/cm parallel grooves replicated in its surface and overcoated with a reflecting material such as aluminum; a first collimating optics, identified as 28 in FIG. 3a, used to collimate the output beam of the laser diode; a first focusing optics, identified as 29 in FIG. 3a, used to inject the collimated output beam into the external integra