Abstract:
In general, the present disclosure is directed to a transmitter optical subassembly (TOSA) module for use in an optical transceiver or transmitter that includes a magnetically-shielded optical isolator to minimize or otherwise reduce magnetization of TOSA components. An embodiment of the present disclosure includes a TOSA housing with magnetic shielding at least partially surrounding an optical isolator, with the magnetic shielding reflecting associated magnetic energy away from components, such as a metal TOSA housing or components disposed therein, that could become magnetized and adversely impact the magnetic flux density of the magnetic field associated with the optical isolator.
Abstract:
A mirror device for use in an optical subassembly is disclosed that includes at least one surface with a visible indicator to allow a technician to differentiate a highly-reflective surface from relatively less reflective (e.g., un-coated) surfaces. The mirror device may be formed using known approaches, such as through the deposition of a metallic material on to a surface of the mirror device followed by one or more optional coating layers. Before, or after, forming the highly-reflective surface, a visual indicator may be introduced on to a surface of the mirror device that is opposite the highly-reflective surface. The visual indicator may comprise, for example, random scratches/scoring etched from a wire brush or tool, paint, epoxy, ink, or any other indicator that allows a technician to visually differentiate the portion of the mirror device having the visual indicator from the highly-reflective portion.
Abstract:
A multi-channel optical transmitter or transceiver includes transmitter optical subassembly (TOSA) modules optically coupled to and directly aligned with mux input ports of an optical multiplexer without using optical fibers. The optical multiplexer may include an arrayed waveguide grating (AWG) or a reversed planar lightwave circuit (PLC) splitter and may be located in a multiplexer housing having at least one side wall with input apertures aligned with the mux input ports. The TOSA modules may include a base supporting at least a laser, laser driving circuitry, and a lens for focusing the light output from the laser. Z-rings may be used to facilitate alignment and to mount the TOSA bases to the side wall of the multiplexer housing, for example, by laser welding.
Abstract:
The present disclosure is generally directed to a lens clip that defines at least one mounting surface for coupling to and supporting an array of optical components, e.g., a laser diode and associated components, and an optical lens slot to receive and securely hold an array of optical lenses at a predetermined position relative to the optical components to ensure nominal optical coupling. The optical lens slot includes dimensions that permit insertion of each optical lens into the same and restrict travel along one or more axis. Accordingly, disposing an optical lens within the lens slot ensures correct alignment along at least two axis, e.g., Z and X, with the third axis (e.g., Y) extending parallel along the slot to permit lateral adjustment of each lens.
Abstract:
Techniques for flexible coupling between an optical coupling receptacle/port of an optical transceiver housing and optical components within the same are disposed. In an embodiment, an optical transceiver housing includes an intermediate fiber with a first end optically coupled to an optical coupling port and a second end optically coupled to a multiplexer/de-multiplexer device, e.g., an arrayed waveguide grating (AWG) device, PLC splitter, and so on. The intermediate fiber may be routed in the transceiver housing in a manner that and the radius of the bends may be optimized to reduce fiber bending losses. The techniques herein are equally applicable to both ROSA and TOSA modules and may be utilized to achieve flexible coupling for multi-channel transceiver devices.
Abstract:
An arrayed waveguide grating (AWG) device for use in an optical transceiver is disclosed, and can de-multiplex an optical signal into N number of channel wavelengths. The AWG device can include an AWG chip, with the AWG chip providing a planar lightwave (PLC) circuit configured to de-multiplex channel wavelengths and launch the same into output waveguides. A region of the AWG chip may be tapered such that light traveling via the output waveguides encounters an angled surface of the tapered region and reflects towards an output interface region of the AWG chip. Thus detector devices may optically couple to the output interface region of the AWG chip directly, and can avoid losses introduced by other approaches which couple an output of an AWG to detectors by way of a fiber array or other intermediate device.
Abstract:
In accordance with an embodiment, a welding assembly is disclosed that allows for a laser assembly to be coupled into a socket of the same and held at a fixed position, e.g., by a mechanical grabber of a welding system. The mechanical grabber may then travel along one or more axis to bring the TOSA module into mechanical alignment with an opening of an associated optical subassembly housing. The welding assembly may further include an alignment member that provides one or more alignment contact surfaces configured to be brought directly into contact with a surface of the associated subassembly housing. When the one or more alignment contact surfaces are “flush” with the surface of the subassembly housing the emission face of the TOSA module is substantially parallel, and by extension, optically aligned with the opening of the associated subassembly housing.
Abstract:
A multi-channel transmitter optical subassembly (TOSA) with an off-center fiber in an optical coupling is disclosed, and can provide passive compensation for beam displacement introduced by optical isolators. The optical coupling receptacle can include an optical isolator configured to receive a focused light beam from a focus lens within the TOSA. The optical coupling receptacle may be offset such that a center line of the focused light beam entering the optical isolator is offset from a center line of a fiber within optical coupling receptacle. Thus the optical isolator receives the focused light beam from the focus lens and introduces beam displacement such that an optical signal is launched generally along a center line of the fiber. Thus the expected beam displacement introduced by the optical isolator is eliminated or otherwise mitigated by the offset between a center line of the fiber and a center position of the focus lens.
Abstract:
Techniques are disclosed for providing relatively short distances between multi-channel transmitter optical subassemblies (TOSAs) and associated transmit connecting circuit in order to reduce losses due to signal propagation delays, also sometimes referred to as signal flight time delays. In an embodiment, a TOSA includes a plurality of laser assemblies disposed along a same sidewall of the TOSA along a longitudinal axis. The TOSA may be disposed within an optical transceiver housing in a transverse orientation, whereby a longitudinal center line of the multi-channel TOSA is substantially perpendicular to the longitudinal axis of the optical transceiver housing. The TOSA may be positioned adjacent an end of the optical transceiver housing having a transmit connecting circuit. Thus each of the plurality of laser assemblies may be positioned at a relatively short distance, e.g., 120 microns or less, away from the transmit connecting circuit.
Abstract:
A multi-channel transmitter optical subassembly (TOSA) with an off-center fiber in an optical coupling is disclosed, and can provide passive compensation for beam displacement introduced by optical isolators. The optical coupling receptacle can include an optical isolator configured to receive a focused light beam from a focus lens within the TOSA. The optical coupling receptacle may be offset such that a center line of the focused light beam entering the optical isolator is offset from a center line of a fiber within optical coupling receptacle. Thus the optical isolator receives the focused light beam from the focus lens and introduces beam displacement such that an optical signal is launched generally along a center line of the fiber. Thus the expected beam displacement introduced by the optical isolator is eliminated or otherwise mitigated by the offset between a center line of the fiber and a center position of the focus lens.