LOW-COST FABRICATION OF OPTICAL SUBASSEMBLIES

The optical subassembly is a major contributor to the cost of a fibero ptic computer data link, A technology fbr low-cost fabrication of opti cal subassemblies is described, with emphasis on a transmitter subasse mbly designed for fiber-channel standard operation (266 Mb/s for 2 km; 1063 Mb/s for 500 m). A factor of three cost reduction is achieved by limiting the parts count to only three: a laser or receiver chip pack aged in a TO-can, a plastic housing, and a plastic aspheric lens; and by employment of a fast, automated active-alignment and subsequent fix ing technique, Key enabling features include the use of precision inje ction molding of specially chosen plastics, an aspheric lens design wh ich permits wide positional variations in the axial direction, and cur ing of a fast setting epoxy through the use of PF power, A tool was co nstructed which produced subassemblies at high yield having satisfacto ry performance.