A tunable filter device includes a wavelength dependent splitter; a tuning element that tunes a characteristic wavelength of the wavelength dependent splitter to a wavelength of an optical signal; and a first optical coupler that splits the optical signal into an input optical signal input to the wavelength dependent splitter and a reference optical signal, where a first output outputs a band stop filtered portion and a second output outputs a band pass filtered portion of the input optical signal. The device further includes a second optical coupler that combines the reference optical signal with the band stopped filtered portion to provide a coupled optical signal; a photodiode that provides at a photocurrent indicating a difference between the wavelength of the optical signal and the characteristic wavelength; and a control loop that provides a control signal for automatically tuning the characteristic wavelength based at least in part on the photocurrent.

Provided here are: a mounting section having a light-emitting element for emitting an optical signal; a mounting section arranged alongside the mounting section and having a light-emitting element for emitting an optical signal that is different in wavelength from the optical signal; and an optical multiplexer having a filter for transmitting therethrough only the wavelength of the optical signal, a mirror for reflecting the optical signal transmitted through the filter, and a filter arranged alongside the filter, for transmitting therethrough only the wavelength of the optical signal, and for reflecting the optical signal reflected by the mirror and multiplexing it with the transmitted optical signal; wherein the light-emitting element is mounted in the mounting section to be displaced toward the light-emitting element from a center in a width direction across an emission direction of the optical signal.

A photonic neural component including optical transmitters, optical receivers, inter-node waveguides formed on a board, multiplexers configured to multiplex input optical signals onto the inter-node waveguides, transmitting waveguides configured to receive optical signals emitted from the optical transmitters and transmit the received optical signals to the inter-node waveguides via the multiplexers, mirrors to partially reflect optical signals propagating on the inter-node waveguides, receiving waveguides configured to receive reflected optical signals produced by the mirrors and transmit the reflected optical signals to the optical receivers, and filters configured to apply weights to the reflected optical signals. The transmitting waveguides and receiving waveguides are formed on the board such that one of the transmitting waveguides and one of the receiving waveguides crosses one of the inter-node waveguides with a core of one of the crossing waveguides passing through a core or clad of the other.

A photonic neural component including optical transmitters, optical receivers, inter-node waveguides formed on a board, multiplexers configured to multiplex input optical signals onto the inter-node waveguides, transmitting waveguides configured to receive optical signals emitted from the optical transmitters and transmit the received optical signals to the inter-node waveguides via the multiplexers, mirrors to partially reflect optical signals propagating on the inter-node waveguides, receiving waveguides configured to receive reflected optical signals produced by the mirrors and transmit the reflected optical signals to the optical receivers, and filters configured to apply weights to the reflected optical signals. The transmitting waveguides and receiving waveguides are formed on the board such that one of the transmitting waveguides and one of the receiving waveguides crosses one of the inter-node waveguides with a core of one of the crossing waveguides passing through a core or clad of the other.

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.

A wavelength division multiplexing filter and methods of forming the same include an optical dielectric filter having multiple dielectric layers. The optical dielectric filter has a high reflectivity at a first wavelength and a high transmissivity at one or more additional wavelengths. The dielectric layers include a structure of layers following the pattern L-[M/2-H-M/2]N-L, where L layers include a first dielectric material, H layers include a second dielectric material, M/2 layers have a mixture of the first and second dielectric material and have a thickness half that needed to provide reflectivity at the first wavelength, and N is a number of repetitions for the structure in brackets.

A method of assembling a wavelength division multiplexing (WDM) cassette for a fiber optic network is disclosed and includes attaching a first plurality of wavelength filters to a first cassette workpiece, attaching a second plurality of wavelength filters to a second cassette workpiece, organizing the optical fibers extending from the wavelength filters, adjusting a length of the optical fibers extending from wavelength filters, and forming an optical connection between the optical fibers from the wavelength filters via a mass fusion splice. The first cassette workpiece and the second cassette workpiece are separate from each during at least one of the attaching, organizing, adjusting, and forming steps. The optical fibers may have predetermined lengths for being arranged in a helix configuration and folded to produce an organized fiber stack that fits within the confines of the cassette. A WDM cassette having an organized arrangement of optical fibers is also disclosed.

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.

A photonic neural component including optical transmitters, optical receivers, inter-node waveguides formed on a board, multiplexers configured to multiplex input optical signals onto the inter-node waveguides, transmitting waveguides configured to receive optical signals emitted from the optical transmitters and transmit the received optical signals to the inter-node waveguides via the multiplexers, mirrors to partially reflect optical signals propagating on the inter-node waveguides, receiving waveguides configured to receive reflected optical signals produced by the mirrors and transmit the reflected optical signals to the optical receivers, and filters configured to apply weights to the reflected optical signals. The transmitting waveguides and receiving waveguides are formed on the board such that one of the transmitting waveguides and one of the receiving waveguides crosses one of the inter-node waveguides with a core of one of the crossing waveguides passing through a core or clad of the other.

A photonic neural component including optical transmitters, optical receivers, inter-node waveguides formed on a board, multiplexers configured to multiplex input optical signals onto the inter-node waveguides, transmitting waveguides configured to receive optical signals emitted from the optical transmitters and transmit the received optical signals to the inter-node waveguides via the multiplexers, mirrors to partially reflect optical signals propagating on the inter-node waveguides, receiving waveguides configured to receive reflected optical signals produced by the mirrors and transmit the reflected optical signals to the optical receivers, and filters configured to apply weights to the reflected optical signals. The transmitting waveguides and receiving waveguides are formed on the board such that one of the transmitting waveguides and one of the receiving waveguides crosses one of the inter-node waveguides with a core of one of the crossing waveguides passing through a core or clad of the other.