Abstract: An optical transceiver assembly for use in a bidirectional system includes an optical fiber to which an outgoing optical signal is coupled. To reduce reflections from the end face of the fiber, the end face is beveled at an acute angle .phi.' to the normal to the fiber axis, and the fiber axis is tilted at an acute angle .theta. to the transmission axis. Preferably, .phi.'.apprxeq.2.theta.. In this manner, crosstalk is reduced without significantly sacrificing coupling efficiency.

Abstract: A system for providing efficient coupling between an elliptical mode laser source and a single mode transmission fiber is disclosed. In one embodiment, the system comprises a cruciform cylindrical lens formed as a pair of perpendicular cylindrical lenses to provide for separate magnification of the "fast" diverging component (i.e., this component passes through a "fast" cylindrical lens) and the "slow" diverging component of the beam (i.e., this component passes through a "slow" cylindrical lens). By decoupling the magnification requirements of the components of the elliptical beam, the beam may be transformed into an essentially circular beam, appropriate for coupling into a single mode fiber. In one arrangement of the present invention, a coupling efficiency of approximately 90% is possible (as compared with prior art coupling efficiency of about 44%).

Abstract: A bidirectional optoelectronic transceiver assembly comprises a pair of interconnectable modules. One module houses a laser diode and a lens; the other a photodiode, a beam splitter and a fiber pigtail.

Abstract: An optical transceiver assembly for use in a bidirectional system includes a beam splitter to direct an incoming signal to a photodiode. An outgoing signal from a laser diode is partially transmitted and partially reflected by the splitter. The reflected signal, which may reach the photodiode, constitutes crosstalk which is reduced by orienting the polarization direction of the splitter essentially parallel to that of the outgoing signal from the laser diode. In another embodiment, which enhances coupling efficiency, a single element asphere lens is positioned between the laser diode and the splitter.

Abstract: An optical transceiver assembly for use in a bidirectional system includes a beam splitter to direct an incoming signal to a photodiode. An outgoing signal from a laser diode is partially transmitted and partially reflected by the splitter. The reflected signal, which may reach the photodiode, constitutes crosstalk which is reduced by means of a cavity positioned to receive the reflected signal and an oblique surface within the cavity adapted to prevent much of the reflected signal from reaching the photodiode.