Abstract: Techniques for high speed optoelectronic coupling by redirection of optical path are disclosed. In one particular embodiment, the techniques may be realized as an optoelectronic receiver comprising an optical signal demultiplexer that may be configured to transmit an optical signal along a first axis, and a photodiode that may be configured to convert the optical signal into an electrical signal, wherein the optical signal demultiplexer may include an inclined end surface that may be configured to reflect the optical signal towards a photoactive area of the photodiode at an obtuse angle of reflection with respect to the first axis.

Abstract: An optically isolated TO-can including a header with electrical connections, a laser diode mounted on the header, and a lens cap positioned over the laser diode so as to enclose and hermetically seal the laser diode. The optically isolated TO-can includes an optical isolator positioned in the TO-can adjacent the laser diode and in the light path of light generated by the laser diode.

Abstract: Locally heated low temperature solder glass is used to permanently fix an optical fiber with sub-micron precision to a glass ceramic submount inside a high power pump laser module. The fiber is manipulated into a predetermined alignment while the solder glass is still molten and the solder glass is then cooled to its solidified state. The predetermined alignment may include an offset to compensate for subsequent thermally related dimensional changes as the solder glass cools and solidifies. If necessary, the solder glass can be remelted and the fiber realigned with a different offset if the first alignment attempt is less than optimal. This alignment process has been demonstrated to provide reliable and efficient coupling of an optical fiber to a high power pump laser within very tight tolerances. A similar process can also be applied to other micro-optics assemblies where high precision, high reliability fiber fixing is required.

Abstract: Locally heated low temperature solder glass is used to permanently fix an optical fiber with sub-micron precision to a glass ceramic submount inside a high power pump laser module. The fiber is manipulated into a predetermined alignment while the solder glass is still molten and the solder glass is then cooled to its solidified state. The predetermined alignment may include an offset to compensate for subsequent thermally related dimensional changes as the solder glass cools and solidifies. If necessary, the solder glass can be remelted and the fiber realigned with a different offset if the first alignment attempt is less than optimal. This alignment process has been demonstrated to provide reliable and efficient coupling of an optical fiber to a high power pump laser within very tight tolerances. A similar process can also be applied to other micro-optics assemblies where high precision, high reliability fiber fixing is required.

Abstract: An optical signal filter for providing a periodic transfer function in transmitting signals within a selected bandwidth, by which passbands are interleavered into groups of separate outputs. The filter employs the transmissivity characteristic of birefringent crystals in conjunction with splitting the input beam into orthogonal and separate components, while compensating for temperature variations by pairing crystals of different types. The transmissivity functions are independent of the polarization of the input beam, and are shaped to flatten transmissivity peaks by the use of cascaded stages of birefringent crystal pairs.

Abstract: A fast acting, low insertion loss switch for use in an optical fiber communication system includes a small diameter waist region incorporating a Bragg grating which is precisely tuned by tensioning to be reflective at a selective wavelength band. By a small physical shift of the waist, as by lateral displacement of an attached small magnetic element with a magnetic field, the periodicity of the grating is varied so that the selected wavelength is passed through the waist with virtually no loss. The incremental motion required can be introduced by a variety of devices, selected in accordance with cost, size and response time requirements. Modules having a number of such switches in close juxtaposition offer distinct advantages for wavelength division multiplexed systems.

Abstract: An optical signal filter for providing a periodic transfer function in transmitting signals within a selected bandwidth, by which passbands are interleavered into groups of separate outputs. The filter employs the transmissivity characteristic of birefringent crystals in conjunction with splitting the input beam into orthogonal and separate components, while compensating for temperature variations by pairing crystals of different types. The transmissivity functions are independent of the polarization of the input beam, and are shaped to flatten transmissivity peaks by the use of cascaded stages of birefringent crystal pairs.

Abstract: Interleavers for optical systems, including multiplexers and demultiplexers, are based on the use of non-birefringent elements in combination with polarization beam splitter to provide differential retardation effects for generation of precise transmittance functions. The retardation elements, in one particular example, are non-birefringent glasses arranged in individually athermal stages but the optical beams propagated through them are maintained in selected polarization states in each stage. Between or within the stages the polarization vectors are varied to match phase to a selected standard, such as an ITU grid. Within the stages, selected beam angle adjustments are made to shape the output transmittance characteristic.

Abstract: Precisely tensioned optical fiber devices are held in a temperature compensated package, with a small diameter span of a fiber containing a Bragg grating of a needed periodicity being supported under tension at opposite ends between spaced apart end members whose thermal expansion characteristics differ from that of an underlying base. The direct points of attachment of the ends of the tensioned span are rotationally as well as axially movable, enabling fine tuning of periodicity and twisting to minimize polarization and dispersion effects. This configuration is also useful for unique methods of assembly of the components, and for use during writing the Bragg grating in the small diameter span.

Abstract: A novel optical subassembly arrangement is proposed. The subassembly comprises a silicon-based submount including a plurality of openings for placement of the various optical components utilized to form the optical subassembly. In particular, a silicon wafer is processed (e.g., etched) using conventional techniques to simultaneously form a large number of individual submounts, each submount processed to include a number of openings. The silicon processing may be sufficiently controlled such that active alignment of the components is minimized. An important feature of the design, when associated with an isolated embodiment, is that the silicon submount is formed to include openings for both the laser and isolator optics such that the openings are disposed along a thermal transport path through the silicon substrate from an attached thermoelectric cooler (TEC). Therefore, the laser and isolator optics are maintained at the same operating temperature.

Abstract: A novel optical subassembly arrangement is proposed. The subassembly comprises a silicon-based submount including a plurality of openings for placement of the various optical components utilized to form the optical subassembly. In particular, a silicon wafer is processed (e.g., etched) using conventional techniques to simultaneously form a large number of individual submounts, each submount processed to include a number of openings. The silicon processing may be sufficiently controlled such that active alignment of the components is minimized. An important feature of the design, when associated with an isolated embodiment, is that the silicon submount is formed to include openings for both the laser and isolator optics such that the openings are disposed along a thermal transport path through the silicon substrate from an attached thermoelectric cooler (TEC). Therefore, the laser and isolator optics are maintained at the same operating temperature.