An optical apparatus for compensating a measurement inaccuracy of polarization dependent loss (PDL) is described. The apparatus comprises a first polarization rotator splitter (PRS) for splitting an input beam into orthogonally polarized X and Y component beams and rotating one of the X and Y component beams to be in the same polarization as the other component beam; first and second circuits for processing the X and Y component beams respectively; a first polarization rotator combiner (PRC) for combining the X and Y component beams processed respectively by the first and second circuits into an output beam, one of the X and Y component beams being rotated to be orthogonally polarized with respect to the other component beam. The apparatus further comprises a first set of photodetectors for monitoring a first relative power between the X and Y component beams before the first and second circuits; a second set of photodetectors for monitoring a second relative power between the X and Y component beams processed respectively by the first and second circuits; and complementary PRSs and PRCs coupled between the first and second circuits and the second set of photo-detectors for compensating a measurement inaccuracy of PDL caused by the first PRS and PRC.

Techniques for forming a photonic integrated circuit having a facet coupler and a surface coupler are described. The photonic integrated circuit may be on a wafer, which may be diced to form an integrated device. The facet coupler may be positioned proximate to an edge of the integrated device, and the surface coupler may be positioned on a surface of the integrated device. The surface coupler may allow for evaluation and assessment of the circuit's performance, which may facilitate wafer-level testing of the circuit and diagnosis of the circuit before and after packaging.

An optical fiber component includes a plurality of optical fibers bundled together at one end at least. The plurality of optical fibers includes a first optical fiber centered at the one end and a plurality of second optical fibers disposed around the first optical fiber at the one end. Each of the plurality of second optical fibers has, at the one end, an end face shape including a straight portion and a corner portion.

A multi-wavelength laser system includes a first fiber laser having a first cavity mirror and a first output coupler, a first optical coupler configured to receive light from the first output coupler, a second fiber laser having a second cavity mirror and a second output coupler, and a second optical coupler configured to receive light from the second output coupler. The multi-wavelength laser system also includes a spectral beam combiner configured to receive first output light from the first optical coupler, receive second output light from the second optical coupler, combine the first output light and the second output light, and form a multi-wavelength output beam.

An environmentally protected PIC, including an InP-based substrate having a first surface that is at least partially provided with an InP-based optical waveguide, and a dielectric protective layer arranged to cover at least the first surface of the InP-based substrate and the InP-based optical waveguide. The dielectric protective layer is configured to protect said PIC from environmental contaminants, to enable confinement of optical radiation in the dielectric protective layer in at least one direction that is transverse to a direction of propagation of the optical radiation, and to allow exchange of the optical radiation between the InP-based optical waveguide and the dielectric protective layer. An opto-electronic system including PIC.

An optical fiber includes a core configured to transmit laser light and a cladding that surrounds the core. In some implementations, an outer surface region of the cladding is tapered or comprises a plurality of notches. The outer surface region of the cladding is configured to cause an aiming beam that falls incident upon the outer surface region of the cladding at a first incidence angle to fall incident upon an outer surface region of the core at a second incidence angle to allow the aiming beam to couple into the core.

An optical coupler includes N members. A Kth (K is an integer of 1 to N) member includes a MCF including P (P is an integer of N or greater) cores, and a marker disposed at a position closest to a first core, and at least one SCF. A core of the SCF of the Kth member is coupled to a coupled core other than the first core. Cores of the MCF of an Mth (M is an integer of 1 to N−1) member are connected to cores of the MCF of an (M+1)th member. A total number of SCF included in the N members is P. Each of P cores of the MCFs configured through the connection of the N members is connected to a core of one of the SCFs.

An object of the present invention is to provide, in a local-light coupling technique for improving efficiency of work, an optical fiber local-light coupling apparatus configured to hardly affect communication between an OLT and an ONU while causing light to leak from a coated optical fiber in such an amount that makes it possible to confirm a communication state.

The optical fiber local-light coupling apparatus according to the present invention includes a first jig including a concave portion curved in a longitudinal direction with respect to a coated optical fiber, and a probe configured to receive leakage light leaking from the coated optical fiber being bent; a second jig including a convex portion curved in the longitudinal direction with respect to the coated optical fiber, the convex portion being configured to sandwich the coated optical fiber between the convex portion and the concave portion of the first jig; a pressing unit configured to apply pressing force in a direction in which the concave portion of the first jig and the convex portion of the second jig approach each other to form a bend in the coated optical fiber; and a reflective film configured to cover a surface of the concave portion of the first jig except for a leakage light passage portion through which, among the leakage light, reception leakage light to be received by the probe passes, and reflect and return the leakage light other than the reception leakage light to the coated optical fiber.

There are provided an optical fiber display system and an optical fiber changeover method each enabling an efficient optical fiber changeover work. The optical fiber display system according to the present invention includes a plurality of core wire identification terminals 101. Each of the core wire identification terminals 101 includes: bent part formation units 11 configured to form a bent part at an optional position of an optical fiber 50 and to leak optical signals propagating through the optical fiber 50 from the bent part; analysis units 12 configured to acquire identification numbers of communication apparatuses (51 and 52) included in the leaked optical signals, the communication apparatuses (51 and 52) being connected to respective ends of the optical fiber 50; a communication unit 13 configured to inquire of a database 201 storing relationship between the optical fiber and the communication apparatuses about the acquired identification numbers of the communication apparatuses, and to receive an identification number of the optical fiber 50 corresponding to the acquired identification numbers of the communication apparatuses, from the database 201; and a display unit 14 configured to display the acquired identification numbers of the communication

Structures for a directional coupler and methods of fabricating a structure for a directional coupler. A first waveguide core has a first section, a second waveguide core has a second section laterally adjacent to the first section, a third waveguide core has a first taper, a second taper, and a third section longitudinally positioned between the first taper and the second taper, and a fourth waveguide core has a first taper, a second taper, and a fourth section longitudinally positioned between the first taper and the second taper. The fourth section is laterally adjacent to the third section, and the third section and the fourth section are positioned either over or under the first section and the second section.