An optical device for coupling light propagating between a waveguide and an optical transmission component is provided. The optical device includes a taper portion and a grating portion. The taper portion is disposed between the grating portion and the waveguide. The grating portion includes rows of grating patterns. A first size of a first grating pattern in a first row of grating patterns is larger than a second size of a second grating pattern in a second row of grating patterns. A first distance between the first row of grating patterns and the waveguide is less than a second distance between the second row of grating patterns and the waveguide.

Multi-directional optical devices are disclosed. The optical device may employ a multiple input/multiple output optical coupling structure to determine propagation direction of received light (in receiver configuration), and/or control the propagation direction of transmitted light (in transmitter configuration). Propagation direction can be determined without the need for moving parts. In accordance with some embodiments, designs of solid-state photonic integrated circuits (PICs) are disclosed herein that utilize N×M star couplers to perform Fourier transformations to light traversing between the N ports and M ports such that light arriving at one or more of the N ports is distributed with a linear phase profile across the M ports. The slope of the linear phase profile is dependent on which of the N ports that light was received from. The light exits from waveguides coupled to the M ports at one or more propagation directions dependent on the linear phase profile.

An optical device for coupling light propagating between a waveguide and an optical transmission component is provided. The optical device includes a taper portion and a grating portion. The taper portion is disposed between the grating portion and the waveguide. The grating portion includes rows of grating patterns. A first size of a first grating pattern in a first row of grating patterns is larger than a second size of a second grating pattern in a second row of grating patterns. A first distance between the first row of grating patterns and the waveguide is less than a second distance between the second row of grating patterns and the waveguide.

An optical grating coupler defining an axis and configured to couple light between a planar waveguide and an optical fiber, including first and second entry surfaces and a plurality of scattering regions symmetric to the axis and arranged such scattering strength presented to incoming light by the plurality of scattering regions changes from weak to strong along a beam path of the incoming light to match a Gaussian mode profile of the optical fiber.

A device may be provided comprising at least one optoelectronic component and at least one optical waveguide, which are configured to transfer light between the optoelectronic component and the optical waveguide, wherein the optical waveguide contains at least one first longitudinal portion in which at least one Bragg grating is introduced, which has a grating constant which is variable along the longitudinal extent of said Bragg grating, and the optoelectronic component is arranged at a lateral distance from the optical waveguide. Alternatively or in addition, a method may be provided for transferring light between at least one optoelectronic component and at least one optical waveguide.

An optical device for coupling light propagating between a waveguide and an optical transmission component is provided. The optical device includes a taper portion and a grating portion. The taper portion is disposed between the grating portion and the waveguide. The grating portion includes rows of grating patterns. A first size of a first grating pattern in a first row of grating patterns is larger than a second size of a second grating pattern in a second row of grating patterns. A first distance between the first row of grating patterns and the waveguide is less than a second distance between the second row of grating patterns and the waveguide.

An optical device for coupling light propagating between a waveguide and an optical transmission component is provided. The optical device includes a taper portion and a grating portion. The taper portion is disposed between the grating portion and the waveguide. The grating portion includes rows of grating patterns. A first size of a first grating pattern in a first row of grating patterns is larger than a second size of a second grating pattern in a second row of grating patterns. A first distance between the first row of grating patterns and the waveguide is less than a second distance between the second row of grating patterns and the waveguide.

Apparatus include a first optical fiber including a core situated to propagate a signal beam at a signal wavelength and an unwanted stimulated Raman scattering (SRS) beam at an SRS wavelength associated with the signal wavelength, and a fiber Bragg grating (FBG) situated in a core of a second optical fiber optically coupled to the core of the first optical fiber, the FBG having a selected grating reflectivity associated with the SRS wavelength and being situated to reflect the SRS beam back along the core of the second optical fiber and to reduce a damage associated with propagation of the SRS beam to power sensitive laser system components optically coupled to the second optical fiber. Methods are also disclosed.

An optical probe includes: an optical fiber; a reflecting portion; and a traveling direction changing portion changing a traveling direction of a laser beam of a first wavelength that has transmitted through the reflecting portion to a direction different from a traveling direction before transmitting through the reflecting portion. Further, the traveling direction changing portion is configured by a bending structure having a structure in which a portion on a distal end side of the optical fiber is bent, and the reflecting portion is provided closer to a proximal end side of the optical fiber than the bending structure.

An embodiment of the indention includes a passive, fiber optic, thermal insulator. The thermal insulator includes an inner sleeve defining a central access port. The thermal insulator includes an outer sleeve concentric to the inner sleeve. The inner sleeve and the outer sleeve are joined sufficient to define an annular void. The thermal insulator includes a first insulator located in the annular void. Optionally, the apparatus includes at least one optical fiber secured in the central access port.