An optical dichroic element adapted to combine first and second light beams into a mixed light beam is provided. The optical dichroic element includes a transparent element, a first reflector and a second reflector. The transparent element is adapted to let the first light beam and the second light beam pass through. The first reflector is disposed on the transparent element. The second reflector is disposed on the transparent element. The first reflector is adapted to reflect the first light beam to the second reflector. The second reflector is adapted to reflect the first light beam and let the second light beam pass through. The first reflector and the second reflector are opposite and not parallel to each other on the transparent element, and an included angle is provided between the first reflector and the second reflector. Moreover, an optical dichroic module including the optical dichroic element is also provided.

An optical receiver module includes: a lens array including a plurality of condenser lenses arranged in one direction to define a plane with optical axes in parallel to each other; and a light receiving element array including a plurality of light receiving elements each configured to receive light emitted from each of the condenser lenses. The light receiving element array includes: a semiconductor substrate to which the light from each of the condenser lenses is input and through which the light is transmitted; and light receiving portions each configured to receive the light transmitted through the semiconductor substrate and convert the light into an electrical signal. A shift of the optical axis of each of the condenser lenses from a center of each corresponding one of the light receiving portions is larger in a direction perpendicular to the one direction within the plane than in the one direction.

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.

A wavelength-division multiplexing (WDM) optical assembly with multiple collimator sets is disclosed herein. The WDM optical assembly includes a WDM optical core subassembly including at least one optical signal router, at least one WDM filter, and a first and second WDM collimator sets. The first WDM collimator set includes a first common optical collimator and at least two channel collimators and the second WDM collimator set includes a second common optical collimator and at least two channel collimators. At least a portion of the first WDM collimator set is optically positioned on a first surface of at least one substrate, and at least a portion of the second WDM collimator set is optically positioned on a second surface of the at least one substrate opposite the first surface. The WDM optical core subassembly increases lane density while decreasing size and minimizing complexity by using a plurality of WDM common ports.

A wavelength division multiplexing and demultiplexing (WDM) assembly is provided that is also capable of performing bidirectional communications. The WDM assembly comprises a WDM module and an adapter for use with the WDM module. The adapter has first and second receptacles in front and back ends thereof, respectively, that are configured to mate with a multi-fiber (MF) connector and with the WDM module, respectively. The MF connector holds ends of M optical fibers and the WDM module has M lenses. The WDM module holds ends of N optical fibers, where N is equal to or greater than 2M. When the MF connector and the WDM module are mated with the first and second receptacles, respectively, the ends of the M optical fibers held in the MF connector are in optical alignment with M lenses, respectively, disposed in the WDM module.

A multiplexer/demultiplexer is provided comprising a capillary filter block, a capillary adhesive, a signal-routing block, and an index-matching adhesive. The capillary adhesive resides in the capillary interstices of the capillary filter block and the index-matching adhesive forms an optical and mechanical interface between the signal-routing block and the capillary filter block. The layer thickness of the index-matching adhesive accommodates for extra-planar surface irregularities in the bonding face of the signal routing block and extra-planar variations along the proximal ends of the component filter blocks of the capillary filter block. The capillary filter block can be formed from a plurality of component filter blocks by dicing multiple component filter blocks from a filter block substrate, placing the component filter blocks adjacent to one another, and using capillary force to draw adhesive between adjacent sidewalls of component filter blocks.

An example device includes a first semiconductor component comprising at least two lasers to emit light at a first wavelength; a second semiconductor component comprising at least two lasers to emit light at a second wavelength, the first wavelength being different from the second wavelength; and an optical multiplexer to receive light from two lasers at the first wavelength and light from two lasers at the second wavelength. The optical multiplexer component includes a first output interface to couple light from one laser at the first wavelength and light from one laser at the second wavelength to a first optical fiber, and a second output interface to couple light from one laser at the first wavelength and light from one laser at the second wavelength beams to a second optical fiber.

In an example embodiment, a WDM array includes an optical filter, N common ports, N reflection ports, and N pass ports. The N common ports may be positioned to a first side of the optical filter. N may be greater than or equal to two. The N reflection ports may be positioned to the first side of the optical filter. The N pass ports may be positioned to a second side of the optical filter opposite the first side.

An optical transmitter including first, second, third and fourth signal generators configured to transmit first, second, third and fourth optical signals, a first filter configured to combine the first optical signal with the second optical signal to form a first multi-channel signal, a second filter configured to combine the third optical signal with the first multi-channel signal to form a second multi-channel signal, and a third filter configured to combine the fourth optical signal with the second multi-channel signal to form a third multi-channel signal. The first optical signal and the third optical signal have parallel optical axes, as do the second optical signal and the fourth optical signal. The second and fourth optical signals are at an angle of from 5? to 40? with respect to the first and third optical signals and are generally propagated in an opposite direction from the first and third optical signals.

Examples include generating a signal using a modulatable source. The signal may be propagated using a multi-mode fiber to receive the signal from the modulatable source. The fiber has a diameter d and a far-field divergence angle associated with the propagated signal that corresponds to a product of the diameter (d) and the far-field divergence angle. The product may be substantially between 1 micron radian and 4 micron radian. In some examples, the propagated signal may be received at a receiver from the multi-mode fiber.